Gas Turbine Operating Manule

Service and Maintenance Instructions for Gas Turbine

Hompu 1/2 - H.2100002.21 THM 1304-12

MAN TURBO AG Version: 02.2008

Table of contents 1

General service and maintenance information .................................... 1 1.1

Safety information......................................................................1

1.2

Abbreviations.............................................................................2

1.3

Performance of service and maintenance measures.................3

1.4

Cleanliness ................................................................................3

1.5

Impact of adhesive tape.............................................................3

1.6

Consumables.............................................................................3

1.7

Examination of component parts ...............................................4

1.8

Identification of component parts...............................................4

1.9

Storage of spare parts ...............................................................4

1.10

Performance of welding work ....................................................4

1.11

Installation of O-rings.................................................................5

1.12

Use of graphite pastes...............................................................5

1.13

General notes on the exchange of component parts .................5 1.13.1 1.13.2 1.13.3 1.13.4 1.13.5 1.13.6 1.13.7

1.14

Use of SWAGELOK adapters....................................................7

1.15

Use of thread sealing tape and thread sealant ..........................8 1.15.1 1.15.2

Thread sealing tape ....................................................8 Thread sealants ..........................................................8

1.16

Storage and installation of hoses...............................................9

1.17

Installation of locking plates.....................................................10

1.18

Snap rings ...............................................................................11

1.19

Use of lockwire ........................................................................11

1.20

Tightening torques...................................................................15 1.20.1 1.20.2 1.20.3

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Safety information .......................................................5 Exchange of pressure switches .................................. 5 Exchange of electric motors........................................5 Exchange of limit switches..........................................6 Exchange of thermometers and pressure gauges ......6 Exchange of swing check valves and shut-off valves..........................................................................6 Exchange of transmitters (resistance thermometers, pressure sensors, etc.) .......................6

Tightening torques for pipe flanged connections ......15 Tightening torques for base engine connections ......15 Tightening torques for other connections..................16

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Service and Maintenance Instructions for Gas Turbine

1.21

Service and maintenance – Definition of terms and objectives ................................................................................ 18 1.21.1 1.21.2 1.21.3

2

Base engine........................................................................................1 2.1

System-related information ....................................................... 1 2.1.1 2.1.2 2.1.3 2.1.4 2.1.5 2.1.6 2.1.7 2.1.8

2.2

2.3

Design and function of base engine ........................... 1 Functional principle .................................................... 1 Calculation of equivalent operating hours .................. 2 Safety information ...................................................... 3 Inspection measures V1, V2, V3, and V4................... 3 Maintenance............................................................... 4 General repair information.......................................... 4 Spare parts catalogue ................................................ 4

Gas generator ........................................................................... 5 2.2.1 2.2.2 2.2.3 2.2.4

Design and function of gas generator......................... 5 Modular design of gas generator................................ 5 Modules of gas generator........................................... 6 Inspection measures V1, V2, V3, and V4................. 15

Power turbine.......................................................................... 16 2.3.1 2.3.2 2.3.3 2.3.4 2.3.5 2.3.6

3

Inspection................................................................. 19 Maintenance............................................................. 19 Repair....................................................................... 19

Design and function of power turbine ....................... 16 Modular design......................................................... 17 LP1 stator blade carrier casing................................. 17 LP turbine rotor / LP2 stator blade carrier ................ 18 Support of LP turbine rotor ....................................... 19 Inspection measures V1, V2, V3, and V4................. 21

Instrumentation base engine...............................................................1 3.1

System-related information ....................................................... 1 3.1.1 3.1.2 3.1.3

3.2

Speed measurement (nGG, nPT) ............................................. 3 3.2.1

3.3

Design and function.................................................... 4 Exchange of T4 thermocouple ................................... 6

Vibration measurement ............................................................. 6 3.4.1

3.5

Design and function.................................................... 3

Inlet temperature measurement on power turbine (T4) ............. 4 3.3.1 3.3.2

3.4

Design and function.................................................... 1 Safety information ...................................................... 3 Inspection................................................................... 3

Design and function.................................................... 6

Phase angle measurement ....................................................... 7

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3.5.1 3.6

Bearing temperature measurement ...........................................7 3.6.1

3.7

System-related information........................................................1 4.1.1 4.1.2 4.1.3 4.1.4 4.1.5 4.1.6

4.2 4.3

Design and function ..................................................11

Vent valve................................................................................11 4.6.1

4.7

Subcontractor documentation ................................... 11 Drawings...................................................................11

Trip valve .................................................................................11 4.5.1

4.6

Design and function ....................................................8

Fuel gas filter ...........................................................................11 4.4.1 4.4.2

4.5

Drawings.....................................................................8

Fuel gas metering valve.............................................................8 4.3.1

4.4

Design and function ....................................................1 Fuel gas specification .................................................1 Safety information .......................................................5 Service and maintenance ...........................................5 Inspection ...................................................................8 Repair .........................................................................8

Job-specific and system-related documents..............................8 4.2.1

Design and function ..................................................11

Pressure transducer ................................................................11 4.7.1

Subcontractor documentation ................................... 11

Ignition system ................................................................................... 1 5.1

System-related information........................................................1 5.1.1 5.1.2 5.1.3 5.1.4 5.1.5

5.2

5.3

Design and function ....................................................1 Safety information .......................................................1 Inspection ...................................................................1 Ignition test .................................................................1 Repair .........................................................................2

Ignition transformer....................................................................3 5.2.1 5.2.2

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Design and function ....................................................7

Fuel gas system ................................................................................. 1 4.1

5

Design and function ....................................................7

Wear measurement on thrust bearing .......................................7 3.7.1

4

Design and function ....................................................7

Design and function ....................................................3 Replacement...............................................................3

Igniters.......................................................................................4

General service and maintenance information © MAN TURBO AG

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Service and Maintenance Instructions for Gas Turbine

5.3.1 6

Guide vane actuator............................................................................1 6.1

System information ................................................................... 1 6.1.1 6.1.2 6.1.3 6.1.4 6.1.5

6.2 6.3

Design and function.................................................... 4

Blow-off and instrument air system .....................................................1 7.1

System-related information ....................................................... 1 7.1.1 7.1.2 7.1.3 7.1.4

7.2

7.3

Design and function.................................................... 3 Replacement .............................................................. 4

Solenoid valves (for activation of blow-off valves)..................... 5 7.3.1

7.4

Design and function.................................................... 1 Safety information ...................................................... 3 Inspection................................................................... 3 Repair......................................................................... 3

Blow-off valves .......................................................................... 3 7.2.1 7.2.2

Design and function.................................................... 5

Pressure sensors compressor discharge pressure / PT inlet pressure ............................................................................ 6 7.4.1

Design and function.................................................... 6

Drainage system.................................................................................1 8.1

System-related information ....................................................... 1 8.1.1 8.1.2 8.1.3 8.1.4

9

Design and function.................................................... 3

Switch - Calibration of guide vane positioning system .............. 4 6.3.1

8

Design and function.................................................... 1 Diagram guide vane angle vs. GG speed................... 2 Safety information ...................................................... 3 Maintenance............................................................... 3 Inspection................................................................... 3

Position sensor ......................................................................... 3 6.2.1

7

Design and function.................................................... 4

Design and function.................................................... 1 Safety information ...................................................... 1 Inspection................................................................... 1 Repair......................................................................... 2

Cleaning system .................................................................................1 9.1

System-related information ....................................................... 1 9.1.1 9.1.2 9.1.3

Design and function.................................................... 1 Time of cleaning ......................................................... 1 Use of cleaning additives ........................................... 2

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9.1.4 9.1.5 9.1.6 9.1.7 9.1.8 9.1.9 9.1.10 9.1.11 9.1.12 9.2

Cleaning nozzles .......................................................................7 9.2.1

9.3

Use of antifreeze.........................................................2 Cleaning sequence .....................................................3 Wash water specification / approved cleaning additives......................................................................3 Safety information .......................................................5 Measures to be taken before initiating the cleaning sequence ......................................................5 Performance of cleaning .............................................6 Measures after cleaning..............................................6 Examination of cleaning result ....................................7 Repair .........................................................................7 Design and function ....................................................7

Mobile cleaning unit ...................................................................8 9.3.1

Design and function ....................................................8

10 Annex ................................................................................................. 1

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10.1

Spare Parts Catalog ..................................................................1

10.2

Curves .......................................................................................1

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1

General service and maintenance information

1.1

Safety information

U DANGER Danger to life and limb as well as risk of severe damage to property! Prior to performance of a service and maintenance measure the Operating Instructions of Machine unit and the safety information included in the system and component part descriptions shall be observed. ATTENTION Damage to components of the gas turbine unit! The general service and maintenance notes listed below have to be observed to avoid damage to the gas turbine unit.

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Service and Maintenance Instructions for Gas Turbine

1.2

Abbreviations AC

Alternating Current

AD

Outer diameter (Aussendurchmesser)

ANPT

American National Pipe Thread

BG

Subassembly (Baugruppe)

DC

Direct Current

DFÜ

Remote data transmission (Datenfernübertragung)

DLN

Dry-Low-NOx, DLN combustion chamber – combustor which is capable of reducing the nitrogen oxides (NOx) generated during combustion, without the injection of water.

GG

Gas generator

GT

Gas Turbine

HP

High Pressure

ID

Inner Diameter

MAX / Max. Maximum MCC

Motor Control Centre (low-voltage switchgear unit)

MIN / Min.

Minimum

LP

Low Pressure

NPT

see ANPT

PT

Power Turbine (PT) = Low Pressure Turbine (LPT)

psia

pound per square inch absolute (absolute pressure)

psig

pound per square inch gauge (gauge pressure)

WAF

Width Across Flats

UNC

Unified National Course Thread

ZB

Assembly (Zusammenbau)

AC

Alternating Current

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1.3

Performance of service and maintenance measures Gas generator, power turbine and coupling may only be replaced or aligned under instruction by a representative of MAN TURBO AG, since special knowledge is required for the performance of these measures. This also applies to the performance of repair work on internal base engine parts. Service and maintenance work which is not described in the documentation supplied may only be carried out by persons with special qualification and skills to whom adequate information is available. Lacking information may be requested from the competent contact for the plant unit with the After Sales Service of MAN TURBO AG.

1.4

Cleanliness Care has to be taken to ensure that dust, dirt, locking elements or other foreign objects do not get into the gas turbine. Should this ever happen, the service and maintenance activity must be interrupted until the respective objects have been found, even if this requires a considerable input of cost and time. Suitable plugs, caps or other covers are to be used for the protection of all non-covered openings. Protective caps for open pipes shall not be placed inside but on top of the pipe ends in order to prevent their being installed unintentionally. Use of adhesive tape is not permitted (see Section 1.5 Impact of adhesive tape [J 1 | 3] ). Anti-corrosion agents, applied for the storage of component parts, as well as dirt and packaging material shall be carefully removed prior to installation of a part. Suitable solvents shall be used for the removal of anti-corrosion agents. After completion of service and maintenance work, especially the intake area is to be thoroughly checked for foreign objects which might, for example, get into the gas path of the base engine.

1.5

Impact of adhesive tape Investigations have shown that remainders of adhesive tape on component parts with increasing temperature attack the surface and reduce the expansion capability. Remainders of adhesive tape are to be removed carefully, before a component part is installed and exposed to high temperatures.

1.6

Consumables During each assembly operation all seals and rubber parts are to be replaced. Prior to installation, non-metallic new parts have to be checked for indications of damage resulting from extended periods of storage. Consumables, such as for example locking wire, locking washers, locking plates, split pins, etc., must not be reused.

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Service and Maintenance Instructions for Gas Turbine

1.7

Examination of component parts Prior to installation of a component part it has to be checked whether the part to be installed is correct and undamaged. Use of incorrect or damaged component parts or of other than original parts not procured from MAN TURBO AG may result in failure or major damage to the plant unit. During disassembly of component parts watch out for indications of wear, burns or other undesirable changes.

1.8

Identification of component parts During disassembly note the installation location of each individual part for ease of reinstallation. Mark the parts, if necessary, taking the following notes into account. Damaged component parts or subassemblies which cannot be reused are to be marked with a tag in order to avoid unintentional installation. The internal parts of gas generator and/or power turbine shall only be marked using special pens. We recommend using the glass chromium pen by Messrs Stade or a silver pen by Messrs Faber for the marking of component parts.

1.9

Storage of spare parts As a rule, spare parts procured from MAN TURBO AG are packaged and preserved for storage according to requirements. Spare parts shall be stored in a room at constant temperature between 15 and 25°C. The relative humidity must not exceed 70%. Temperature variations are to be limited to max. 1°C per hour. Anti-friction bearings are delivered in the manufacturer's original packaging. As a rule, the maximum storage period is 2 years. After this, exchange the parts if preservation proves too expensive. Component parts from rubber-like materials, e.g. shaft sealing rings, Orings, flexible nozzles, vibration dampers, V-belts, etc. have to be protected from light and seal-welded into black film. Check these parts annually for elasticity and brittleness. The maximum storage period is 5 years or less, depending on the instructions by the respective manufacturer. For this reason, these parts are to be marked with the date of storage to permit checking. Stored component parts with metallic surfaces are to be checked annually. The preservation of machined surfaces has to be touched up, if necessary. Bright, metallic surfaces are to be greased. Stored component parts shall be identified with the material number of MAN TURBO AG and recorded in an inventory list.

1.10

Performance of welding work If welding work is carried out in the area of the GT base frame, proper earthing must be ensured in order to avoid damage to the electrical

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components installed on the base frame. Additionally, appropriate fire prevention measures are to be taken. 1.11

Installation of O-rings For ease of installation, O-rings which come into contact with oil are to be coated with the oil of the system in which the O-ring is used. O-rings which come into contact with water may be coated with Vaseline for ease of installation.

1.12

Use of graphite pastes To facilitate future removal of screwed joints in hot areas, graphite paste Never-Seez (Material No. S0913821) shall be applied to the thread faces.

1.13

General notes on the exchange of component parts

1.13.1

Safety information U CAUTION Hazard of personal injury and damage to property! Prior to the dismounting of component parts the Operating instructions for Machine unit shall be observed.

1.13.2

Exchange of pressure switches Z Observe Section 1.13.1 Safety information [J 1 | 5] .

1. Shut down the plant unit and lock it to prevent restarting. 2. Isolate the measuring line, and depressurize. 3. De-energize the measuring circuit to exclude any risk of a short circuit which may result in damage to digital/analog cards. 4. Exchange the pressure switch. 5. Use a calibration device to check the measuring range and the switch point. Adjust the switch point, if necessary (for values see). 1.13.3

Exchange of electric motors In the case of motors which are new, which have been cleaned or repaired and in the case of motors which have been in store or shut down for 6 months, determine the minimum insulation resistance of the motor winding. After an extended period of operation also check the critical insulation resistance. During and immediately after the measurement the terminals sometimes have dangerous voltages and must not be touched. If the minimum insulation resistance or critical insulation resistance has decreased below the specified value, the motor must not be started up or has to be shut down at once.

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Service and Maintenance Instructions for Gas Turbine

Possible causes for this could be, for example, humidity, damaged windings or winding parts. Z Observe Section 1.13.1 Safety information [J 1 | 5] . 1. Shut down the plant unit and lock it to prevent restarting. 2. Safely isolate the motor. 3. Lock the motor to prevent restarting. 4. Verify safe isolation from supply. 5. Ground and short-circuit the motor. 6. Cover or barrier off adjacent, live parts. 7. Reverse the above measures only after the motor has been completely reinstalled and connected again. 1.13.4

Exchange of limit switches Z Observe Section 1.13.1 Safety information [J 1 | 5] .

1. Shut down the plant unit and lock it to prevent restarting. 2. De-energize the measuring circuit to exclude any risk of a short circuit which may result in damage to digital/analog cards. 3. Exchange the limit switch. Note: If the limit switch is designed as initiator, make sure that the polarity is correct. 1.13.5

Exchange of thermometers and pressure gauges Z Observe Section 1.13.1 Safety information [J 1 | 5] .

1. Shut down the plant unit and lock it to prevent restarting. 2. Isolate the piping, and depressurize. 3. Exchange the thermometer or pressure gauge. 1.13.6

Exchange of swing check valves and shut-off valves Z Observe Section 1.13.1 Safety information [J 1 | 5] .

1. Shut down the plant unit and lock it to prevent restarting. 2. Isolate the piping, and depressurize. 3. Exchange the swing check valve or shut-off valves. Use new gaskets and observe the direction of flow. 1.13.7

Exchange of transmitters (resistance thermometers, pressure sensors, etc.) Z Observe Section 1.13.1 Safety information [J 1 | 5] .

1. Shut down the plant unit and lock it to prevent restarting.

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2. De-energize the measuring circuit to exclude any risk of a short circuit which may result in damage to digital/analog cards. 3. Exchange the transmitter. Note: If the transmitter is designed as initiator, make sure that the polarity is correct. 4. For exchanging a resistance thermometer in case an immersion sleeve is not installed: Isolate the piping, and depressurize. 5. Use a calibration device to check the setting or programming and function, and pass through the entire measuring range for checking the linearity (values see). 1.14

Use of SWAGELOK adapters In the gas turbine area SWAGELOK® adapters are used with a maximum diameter of 25 mm since pre-assembly tools are not necessary up to this size. SWAGELOK® adapters can be loosened and re-tightened several times without any of the parts shown in the illustration below having to be exchanged.

SWAGELOK adapter

1

Cap nut

3

Front clamping ring

2

Rear clamping ring

4

Body

Z If an adapter has to be exchanged or installed all the same, take care to

ensure that the pipe end is rectangular and free from burs. Remnants from burs and other contaminations must not get into the piping. The following procedure has to be observed:

1. Insert the pipe into the assembled SWAGELOK® adapter. Make sure that the pipe has been introduced into the adapter up to the stop and the cap nut tightened "finger-tight". 2. Prior to tightening the cap nut mark it in 6 o'clock position. 3. While holding the body with a wrench tighten the cap nut by 1-1/4 turns. Note that the marking has to be turned further up to 9 o'clock position after one complete turn.

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Service and Maintenance Instructions for Gas Turbine

NOTE Use of sealants. Sealants must not be applied to SWAGELOK® adapters. On SWAGELOK® adapters the measurement of tightening torques is not a suitable means for checking the tightening. Merely the 1-1/4 turn of the cap nut is the correct measure for adequate tightening. If the reference gauge fits between the cap nut and the body hexagon, the adapter has not been tightened sufficiently. If it does not fit, the adapter has been tightened sufficiently. 1.15

Use of thread sealing tape and thread sealant

1.15.1

Thread sealing tape NOTE Use of thread sealing tape. Thread sealing tape may only be used for tapered male threads. Use for connections with flanges, cones or pipe unions is not allowed. Z For tapered male threads with a diameter of 1/8", 1/4" and 3/8" a thread

sealing tape with a width of 1/4" is to be used. For a larger thread a tape of ½" width is to be used. The following procedure has to be observed:

1. Clean the male and female threads in order to remove any anti-seize compound or sealing residues. 2. Starting on the first flight, wind the sealing tape with slight overlap around the thread in threading direction. For tapered threads from special steel, winding the tape twice around the thread is recommended. 3. Make sure that the tape does not protrude beyond the first turn of the thread, since otherwise it might break and get into the structural component. 4. Protruding sealing tape has to be cut off. The tape, especially the overlapping ends, shall be pressed against the thread. 1.15.2

Thread sealants NOTE Use of thread sealants. Thread sealants may only be used for tapered male threads. Use for cable glands is not permitted. Prior to the application of thread sealant the whole thread has to be cleaned from oil, grease and other impurities. The thread sealant is to be applied to the second and third flights.

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1.16

Storage and installation of hoses NOTE Open hose ends. Open ends of stored hoses have to be capped or plugged in order to prevent any accumulation of dirt in the hose interior. Z The service life of a hose largely depends on the correct installation.

The following has to be observed for the installation of hoses:

1. Hoses shall be reeled and unreeled as shown in the following illustration "Reeling and unreeling of hoses". 2. Check prior to installation that the hose interior is free from dirt. As a precautionary measure blow the hose through with compressed air prior to installation. 3. As a rule, the hoses are equipped with one loose and one fixed hose connection fitting. The fixed hose connection fitting always has to be tightened first to prevent torsional stress. 4. Always use a wrench as dolly to avoid co-rotation of the connection mating piece or damage to the piping to be connected. 5. External straining of the hose by chafing on edges, surfaces or on the ground has to be avoided, as the service life may be reduced considerably by bending or by reduction of the wall thickness. 6. During installation care must be taken that the minimum bending radius specified in the table below is maintained. 7. Attachment of a hose in the way such as illustrated in "Inadmissible attachment of hose" is not permissible.

Reeling and unreeling of hoses

Hose minimum bending radius

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Service and Maintenance Instructions for Gas Turbine

Inadmissible attachment of hose

Minimum bending radius for corrugated hoses of special steel

1.17

Nominal diameter (inch)

Bend minimum radius (mm)

3/8

200

1/2

220

5/8

300

3/4

330

1

390

1-1/4

410

1-1/2

490

2

570

2-1/2

680

3

770

4

960

Installation of locking plates NOTE Reuse of locking plates! Locking plates must be used only once. When using locking plates care has to be taken to ensure that the gap between the bent-over tabs and the contact face is max. 0.50 mm. At least 75% of the securing tab must be in contact with the face of the structural component.

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Installation of locking plates

1.18

Snap rings Suitable pliers are to be used for the installation of snap rings. Internal snap rings must not be pressed together beyond the point where the ends of the rings meet. External snap rings must only be expanded to such an extent that installation is possible without bending the rings. After installation it has to be ensured that the snap ring rests firmly in the groove and is neither loose nor deformed. Deformed snap rings have to be replaced. Chamfered snap rings additionally serve for absorbing the tolerance clearance of the structural component to be retained. Such snap rings have a chamfer of 15° on one side. Chamfered snap rings may only be inserted in correspondingly chamfered grooves. The non-chamfered side is to be directed towards the structural component to be retained.

1.19

Use of lockwire NOTE Use of lockwire. The use of lockwire which has been in use before, which is bent or damaged is not admissible. No other than the lockwire supplied by MAN TURBO AG shall be used. The bores for the lockwire are to be aligned as shown in the following illustrations. During alignment the specified tightening torques must not be exceeded. Subsequently, the lockwire is to be fitted as shown. The end of the lockwire has to be bent over to avoid any hazard of injuries. In THM gas turbine units lockwires with a diameter of 0.8 (material no. S0293782) and 1.25 mm (material no. S0293781) are used. In FT8 gas turbine units lockwire of material no. TAS3214-02 is mainly used.

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Service and Maintenance Instructions for Gas Turbine

Examples for the securing of component parts with lockwire

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© MAN TURBO AG

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Examples for the securing of component parts with lockwire

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Service and Maintenance Instructions for Gas Turbine

Examples for the securing of component parts with lockwire

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1.20

Tightening torques U CAUTION Hazard of personal injury and damage to machinery. If tightening torques are not observed, structural components may work loose and - especially where rotating structural components are concerned - may hit people in the vicinity of the plant unit. Above that, hot and pressurized liquids or gases may escape from pipes and casings and likewise hit people in the vicinity of the plant unit. NOTE Prerequisites for the tightening of threaded unions. Structural components shall only be tightened to the final torque after room temperature has been reached. Flanged connections are to be tightened crosswise alternately with approx. 75% of the tightening torque, before the final tightening torque is reached. Torque wrenches are to be calibrated regularly. For information about the tightening torques for the driven machine and other plant unit components please refer to the relevant documentation.

1.20.1

Tightening torques for pipe flanged connections In most cases, threaded bolts with UNC thread are used for the connection of pipe flanges. Flanged connections are to be tightened alternately and crosswise by applying the following tightening torques. The data apply for non-greased threaded bolts which are stamped with "B7" on the front face. Where the stamping is different, other tightening torques apply. Tightening torques for stud bolts with UNC thread

1.20.2

Dimension (inch)

Tightening torque (Nm)

1/2

95

5/8

199

3/4

347

7/8

554

Tightening torques for base engine connections The following table lists the standard tightening torques for the base engine. Do not apply these tightening torques unless in the description of service and maintenance measures express reference is made to the tightening torques in this table. In all other cases special tightening torques apply which must be observed by all means.

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Service and Maintenance Instructions for Gas Turbine Tightening torques for base engine connections Bolt / nut diameter

Minimum (Nm)

Maximum (Nm)

M5

2.6

3

M6

4.8

6

M8

11

15

M 10

23

28

M 12

39

45

M 14

63

80

M 16

96

130

M 18

130

180

M 20

187

250

M 22

250

320

M 24

320

450

M 27

469

580

M 30

588

750

If not indicated otherwise, thread faces are to be greased.

1.20.3

Tightening torques for other connections NOTE Tightening torques for other connections. The tightening torques listed in the table below are not valid for the base engine and for flanged pipe connections. The standard tightening torques for other connections are indicated in the following table. Do not apply these tightening torques unless in the description of service and maintenance measures express reference is made to the tightening torques in the table below. In all other cases special tightening torques apply which must be observed by all means. Tightening torques for other connections (part 1 of 2) Bolt / nut diameter

Bolt strength category/ Material

Tightening torque Ma (Nm) MoS2 - lubr.

Tightening torque Ma (Nm) lightly oiled

M8

5.6

10

11

8.8

21

19

10.9

30

34

A2-70

12

13

A4-80

17

19

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Bolt / nut diameter

M10

M12

M16

M20

Bolt strength category/ Material

Tightening torque Ma (Nm) MoS2 - lubr.

Tightening torque Ma (Nm) lightly oiled

1.7258

15

17

5.6

20

23

8.8

43

48

10.9

so

68

A2-70

23

26

A4-80

33

38

1.7258

29

33

5.6

33

40

8.8

71

85

10.9

100

120

A2-70

39

47

A4-80

56

67

1.7258

49

59

5.6

83

117

8.8

178

248

10.9

250

350

A2-70

97

136

A4-80

139

194

1.7258

122

171

5.6

150

200

8.8

320

426

10.9

450

600

A2-70

175

233

A4-80

250

333

1.7258

220

293

Tightening torques for other connections (part 2 of 2)

Version 02.2008

Bolt / nut diameter

Bolt strength category/ Material

Tightening torque Ma (Nm) MoS2 - lubr.

Tightening torque Ma (Nm) lightly oiled

M24

5.6

267

367

8.8

569

782

10.9

800

1.100

A2-70

311

428

A4-80

444

611

General service and maintenance information © MAN TURBO AG

1 | 17 - 19

Service and Maintenance Instructions for Gas Turbine Bolt / nut diameter

M27

M30

M36

1.21

Bolt strength category/ Material

Tightening torque Ma (Nm) MoS2 - lubr.

Tightening torque Ma (Nm) lightly oiled

1.7258

391

537

5.6

417

550

8.8

889

1.173

10.9

1250

1.650

A2-70

486

641

A4-80

694

917

1.7258

611

807

5.6

550

733

8.8

1.173

1.564

10.9

1.650

2.200

A2-70

642

856

A4-80

917

1.222

1.7258

807

1.076

5.6

933

1.267

8.8

1.991

2.702

10.9

2.800

3.800

A2-70

1.089

1.478

A4-80

1.556

2.111

1.7258

1.368

1.858

Service and maintenance – Definition of terms and objectives Service and maintenance is aimed at maintaining or restoring the desired condition of the plant unit. Service and maintenance which is carried out regularly and carefully has a positive effect on the reliability of the plant unit and contributes to reduction of the operating costs. The following measures are covered by the term service and maintenance: ■ Maintenance measures (cleaning, readjustment) for maintaining the desired condition; ■ Inspection measures (measurement, check, diagnosis) for assessment of the actual condition; ■ Repair measures (replacement, rework) for restoring the desired condition.

General service and maintenance information 1 | 18 - 19

© MAN TURBO AG

Version 02.2008

1.21.1

Inspection

1.21.1.1

Routine inspections / walk-around checks The overall process plant has to be inspected daily for external damage, leakages and safe attachment. If continuous operation of the plant unit does not allow inspection of the components installed inside the acoustic enclosure they are to be inspected after every run-down.

1.21.1.2

Oil analyses The oil analyses which are to be carried out regularly are aimed at permitting statements about the degree of fouling, ageing or the additive values, and at protecting the unit against inadequate cooling of the bearings due to excessive viscosity, detrimental deposits and corrosion in the areas of the lube-oil system of gas generator and power turbine. For information about the applicable requirements please refer to the lube oil specification.

1.21.1.3

Checking of major functional component parts and protective equipment Service and maintenance is aimed at maintaining or restoring the desired condition of the plant unit. Service and maintenance which is carried out regularly and carefully has a positive effect on the reliability of the plant unit and contributes to reduction of the operating costs. The following measures are covered by the term service and maintenance: ■ Maintenance measures (cleaning, readjustment) for maintaining the desired condition; ■ Inspection measures (measurement, check, diagnosis) for assessment of the actual condition; ■ Repair measures (replacement, rework) for restoring the desired condition.

1.21.2

Maintenance Major maintenance measures include regular filling of the lube oil tank, cleaning of the gas generator compressor and relubrication of motors. The information in the respective system or component part description has to be observed before maintenance work is started.

1.21.3

Repair Repair of component parts or subassemblies is mainly carried out depending on the respective actual condition, which means that fixed dates and/or regular intervals for repair measures are not specified. Relevant information provided by MAN TURBO AG shall only be regarded as reference values for planning purposes. Point in time and scope of necessary repairs depend on the operating conditions and on the state and/or operating behaviour of the plant unit.

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General service and maintenance information © MAN TURBO AG

1 | 19 - 19

2

Base engine

2.1

System-related information

2.1.1

Design and function of base engine Gas generator and LP turbine are the core components of the gas turbine unit. They are collectively referred to as base engine which is mounted on a base frame.

2.1.2

Functional principle The THM is a twin-shaft gas turbine operating according to the conventional simple principle of combustion at constant pressure. This principle (see the figure below) comprises the following steps: ■ Adiabatic compression of air (i.e. without exchange of heat) in an axialcentrifugal compressor. ■ Combustion of a mixture at constant pressure in two combustion chambers. The mixture consists of the air discharged from the compressor and the fuel (liquid fuel or fuel gas) which is routed to the combustion chambers via nozzles. ■ Initial expansion of the pressurized hot gases from the combustion chambers takes place in a two-stage backpressure turbine which is referred to as high-pressure turbine (HP turbine) and which is used for drive of the axial-centrifugal compressor. ■ Secondary expansion of the hot gases leaving the HP turbine takes place in a second backpressure turbine which is referred to as lowpressure turbine or power turbine (LP turbine or PT). This turbine supplies the energy required for driving a processing machine (e.g. pipeline compressor or electric generator) via a shaft that is not connected to the HP turbine of the gas generator.

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Base engine © MAN TURBO AG

2 | 1 - 22

Service and Maintenance Instructions for Gas Turbine

Functional principle of gas turbine

2.1.3

1

Gas generator compressor

5

Driven machine

2

Combustion chamber

6

Temperature curve

3

Gas generator turbine

7

Pressure curve

4

Power turbine

Calculation of equivalent operating hours Calculation of the equivalent operating hours (EOH) in the course of determination of service and maintenance intervals or service lives is necessary for the consideration of factors which have a major influence on the condition of the base engine parts. Calculation is based on the following formula: EOH = operating hours ∙ A 1 ∙ A 2 ∙ A 3 + 10 ∙ number of starts Factors for calculation of the equivalent operating hours Factor A1

Operating conditions Weighting factor for load stage Base load (operation at nGG or T4 limitation)

1.0

Operation predominantly below 80% base load

0.9

Base load operation with recurring, short-term overload above the T4 limitation for base load

2.0

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Base engine 2 | 2 - 22

Value

© MAN TURBO AG

Factor

Operating conditions

A2

Value

Weighting factor for fuel Low-sulphur fuel gas

1.0

High-sulphur fuel gas

1.3

Fuel oil EL, Diesel

1.3

Other fuels A3

2.1.4

on request

Weighting factor for suction air Low-pollutant suction air

1.0

Corrosive suction air, e.g. off-shore operation

1.3

Safety information WARNING Hazard of personal injury and damage to property. Work on base engine components may only be carried out during standstill and after a cool-down period of several hours. Prior to performance of service and maintenance measures the following Sections shall be observed.

2.1.5

Inspection measures V1, V2, V3, and V4 Inspection measures V1, V2, V3, and V4 are aimed at assessing the condition of the internal base engine components. The following tables provide an overview of the times for performance of these measures and of the scope of components to be inspected. At the time of inspection of the base engine, the component parts and protective equipment which are relevant for proper functioning may be checked. Inspection times for base engine Equival. OH*

10

20

30

40

50

60

70

80

90

...

Measure

V1

V2

V2

V3

V1

V2

V2

V4

V1

...

* OH = Operating Hours. The values are to be multiplied by 1,000. Scope of base engine parts to be inspected Inspection measure V1

V2

V3

V4

Flame tubes

Compressor

Gas collector

Combustion chambers

HP1/HP2 stator blades

Gas collector

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Base engine © MAN TURBO AG

2 | 3 - 22

Service and Maintenance Instructions for Gas Turbine Inspection measure V1

V2

V3

V4

HP1/HP2 rotor blades

HP turbine

LP1 stator blades

LP turbine

Flame tubes

Compressor

 Checking of major functional component parts and protective

equipment [J 1 | 19] 2.1.6

Maintenance Maintenance work (cleaning, readjustment) on the base engine is limited to keeping the outer area and/or the surroundings of the base engine clean and to condition-dependent cleaning of the compressor.

2.1.7

General repair information Repair of the components of the base engine depends on the respective condition, which means that fixed dates and/or regular intervals for repair measures are not specified. Relevant information provided by MAN TURBO AG shall only be regarded as reference values for planning purposes. Point in time and scope of necessary repairs depend on the operating conditions and on the state and/or operating behaviour of the plant unit. Assessment of the actual condition is made by the timedependent repair measures V1, V2, V3 and V4 as well as based on the evaluation of operating data.

2.1.8

Spare parts catalogue Data of spare parts for the base engine are listed in an electronic spare parts catalogue which will be found on the electronic documentation data carrier included in the supply. This catalogue which is structured according to subassemblies covers all component parts of the base engine which are indicated in parts lists and explosion drawings. A search function is available for finding parts e.g. by means of the part no. or part designation. Above that, a facility is provided for generating spare parts enquiries or purchase orders. If requested, the EPOS© Electronic Parts Ordering System can be set up; this system makes it possible - via the internet - to look e.g. for spare parts prices, delivery times, and parts available from stock. Furthermore, enquiries or purchase orders for spare parts can be submitted to MAN TURBO AG via the internet.

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Base engine 2 | 4 - 22

© MAN TURBO AG

2.2

Gas generator

2.2.1

Design and function of gas generator The compressor, the combustion chamber section, and the HP turbine are the main components of the gas generator and are shown along with other components in the following figure. The gas generator generates the energy required for drive of the power turbine. Having passed through the compressor, the air drawn in enters the Vshaped combustion chambers where it is mixed and burnt with the fuel. Via a gas collector the hot exhaust gases reach the two-stage HP turbine which drives the compressor of the gas generator. The surplus exhaust gas energy is transferred further to the power turbine (LP turbine). Part of the air from the compressor is also used for cooling the combustion chambers and turbines. Ignition is made by two igniters operating independently from each other. Subsequently, combustion is self-sustaining. Fuel supply to the gas generator is adjusted by means of a control valve with reference to the power requirement.

2.2.2

Modular design of gas generator The following figure illustrates the modular design of the gas generator of a THM 1304 gas turbine unit with standard combustion chambers. The modular design of a THM permits the exchange of all modules inside the acoustic enclosure with only few equipment needed.

Modular design of gas generator

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Base engine © MAN TURBO AG

2 | 5 - 22

Service and Maintenance Instructions for Gas Turbine 1

Gas generator

9

Upper half compressor stator blade carrier

2

Combustion chamber

10

Planetary gear unit*

3

Flame tube

11

Planetary gear unit connecting shaft*

4

HP1 stator blade carrier

12

GG front bearing

5

HP turbine rotor

13

Compressor inlet casing

6

HP2 turbine ring

14

Compressor rotor

7

Upper half GG main casing

15

Upper half GG rear bearing

8

Gas collector

16

Lower half GG main casing

*

These parts are only installed in units with a starter system equipped with an auxiliary gearbox.

 Compressor inlet casing [J 2 | 6]  Combustion chambers [J 2 | 11]  Gas collector [J 2 | 10]  HP turbine [J 2 | 11]  Support of the GG rotor [J 2 | 13]  Compressor [J 2 | 8]

2.2.3

Modules of gas generator

2.2.3.1

Compressor inlet casing The compressor inlet casing is a single-part casing with four hollow struts which interconnect the inner and outer casings. The inlet casing accommodates the GG front bearing for supporting the rotor. Further components of the inlet casing are 18 inlet guide vanes (IGV's) with an associated adjusting mechanism / actuator (see figure below). The first stator blade / guide vane row of the GG compressor on the THM 1304 is of adjustable design in order to allow control of the air flow rate (especially during start-up and rundown as well as during turndown). This control feature makes it possible to achieve an optimum GG compressor efficiency throughout the total speed range. Actuation of the adjusting mechanism by means of an electrically operated stepping motor is initiated by the GT control system as a function of the GG speed.

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Base engine 2 | 6 - 22

© MAN TURBO AG

The description of the guide vane positioning system includes a diagram which illustrates the speed-dependent guide vane position as well as the other components of the guide vane positioning system.

Compressor inlet casing

1

Strut

4

Variable inlet guide vane

2

Guide vane positioning mechanism

5

Front GG bearing

3

Bore for instrument cable

Version 02.2008

Base engine © MAN TURBO AG

2 | 7 - 22

Service and Maintenance Instructions for Gas Turbine

ATTENTION Risk of machine damage! The linkage of the guide vane positioning mechanism has been set and tested at works. This setting must only be changed by MAN TURBO AG.

Guide vane positioning

2.2.3.2

1

Actuating ring

3

Lifting rod

2

Inlet casing

4

Vane closing direction

Compressor The compressor of the THM 1304 which supplies the air required for combustion and/or cooling is a 10-stage axial compressor with one centrifugal stage and consists of the following major components: ■ Main casing (2 parts), ■ Stator blade carrier (2 parts), ■ Axial rotor. The air flows through the individual stages of the axial compressor and is compressed accordingly. This compression also results in an increases in the air temperature. The radial flow impeller of the compressor rotor subsequently deflects the air flow by 90° and directs it into the smoothing chamber via a diffuser which effects a reduction of the flow velocity (see figure below). The smoothing chamber consists of the compressor stator blade carrier casing and the GG main casing. Subsequently, the major

Version 02.2008

Base engine 2 | 8 - 22

© MAN TURBO AG

part of the air present there is routed through two elbows into the combustion chambers. The residual air is passed on via ducts and bores for cooling of the HP turbine which serves as driver for the compressor rotor.

Compressor design and numbering of stages

1

Annular duct stage 3

4

Stator blades

2

Annular duct stage 6

5

Smoothing chamber

3

Rotor blades

3

Axial compressor

GG rotor

1

Radial stage

2

HP turbine

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Base engine © MAN TURBO AG

2 | 9 - 22

Service and Maintenance Instructions for Gas Turbine

Blading Identification of the compressor stages had to be adapted in the course of further development of the THM 1304 as the compressor capacity was continuously increased by adding stages 000, 00 and 0. All compressor blades are provided with an anti-corrosion coating. Teflon segments are screwed to the tips of the stator blades of stages 000, 00, 0, 1 and 2. The labyrinth strips at the rotor discs of the compressor rotor work into the Teflon in the course of the first operating hours. This kind of sealing makes it possible to minimize clearances and thus to keep the performance and/or efficiency losses low. The discs (into which the blades are inserted in dovetail grooves), the radial flow impeller and the shaft ends of the rotorare held together by 13 tie bolts. Blow-off and cooling system Under certain operating conditions compressor air has to be removed via blow-off valves in order to prevent surging of the compressor. For this purpose, the compressor stator blade carrier is fitted with radially running grooves between the 2nd and 3rd as well as between the 5th and 6th stages, via which the compressor air is routed into two annular ducts. Depending on the type of machine, the drawn-off air is discharged via two or three blow-off valves installed on top of the GG main casing. The blowoff valves installed on the bottom GG main casing half (one or two, depending on the machine type) serve to remove the compressor air from the last stage. For further information about the arrangement and purpose of the blow-off valves please refer to the description of the blow-off and instrument air system. 2.2.3.3

Gas collector The gas collector guides the hot exhaust gases from the combustion chamber into the HP turbine. The gas collector is cooled from outside with the air that has been routed before via the smoothing chamber into the combustion chambers for cooling of the flame tubes. The lower section of the gas collector accommodates a drain connection.

Version 02.2008

Base engine 2 | 10 - 22

© MAN TURBO AG

Gas collector

1

Gas collector

2.2.3.4

Combustion chambers

2.2.3.5

HP turbine

2

Drain connection

The HP turbine of the gas generator (an axial-flow two-stage backpressure turbine) consists of the following components: ■ HP1 stator blade carrier, ■ HP turbine rotor, ■ HP2 stator blade carrier (2-part, vertical split joint).

Version 02.2008

Base engine © MAN TURBO AG

2 | 11 - 22

Service and Maintenance Instructions for Gas Turbine

HP turbine

1

HP turbine rotor

3

HP2 stator blade carrier casing

2

HP1 stator blade carrier

4

HP2 stator blade

The single-part HP1 stator blade carrier which is centred by eight pins on the GG main casing consists of one inner and one outer support ring as well as the HP1 stator blades. The inner ring is bolted to the gas collector and the outer ring to the GG main casing. The HP turbine rotor consists of two discs and the HP1 and HP2 rotor blades, inserted in fir-tree-shaped grooves. The pair of discs is connected to the rear shaft end of the compressor rotor by four centring pins and four

Version 02.2008

Base engine 2 | 12 - 22

© MAN TURBO AG

bolts.Sealing of the HP turbine rotor is by honeycomb seals. In the course of the first operating hours, the labyrinth strips mounted on the rotor blades and on the turbine disc work into the honeycomb seals. This kind of sealing keeps the clearances and as such the performance and efficiency losses very low. For inspection of the hot gas parts, one carrier half can be removed (after having shifted apart the gas generator and the power turbine). 2.2.3.6

Support of the GG rotor The GG rotor is supported by two hydrodynamic tilting pad sleeve bearings. With this bearing type, the lube oil pressure required for supporting the shaft is generated by the rotary movement of the GG rotor. With increasing speed, more and more oil is transferred from the contact surface of the shaft into the lubricating gap. As a result, the oil pressure in the lubricating gap increases until the shaft floats on the lube oil film. The GG front bearing comprises one axial thrust, axial backpressure and sleeve-type radial bearing each. During start-up the backpressure bearing absorbs the axial force acting opposite to the direction of flow. At higher speeds, the conditions of the axially acting forces change and the rotor is pressed against the thrust bearing in the direction of flow. Sealing towards the compressor space at the rear end of the GG front bearing is made via a floating ring sliding on the shaft end of the GG rotor and via a labyrinth seal. The required seal air is routed from the inner area of the compressor rotor to the labyrinth seal through bores. Thrust and backpressure bearings are formed by 12 ball-supported tilting pads each. The sleeve bearing which serves for absorption of the radially acting forces consists of five tilting pads. The GG rear bearing like the GG front bearing is of two-part design, but consists of one sleeve bearing only, the design of which is similar to that of the GG front bearing. Contrary to the GG front bearing, sealing at both ends of the bearing is made via floating rings and labyrinth seals. The seal air is routed through the inner area of the compressor rotor and through bores to the labyrinth seals. Supply of lube oil to the GG front bearing is made through a line connected to the GG inlet casing. Through internal ducts and lines, the oil is fed into the annulus of the bearing and injected there through five bores located between the tilting pads of the sleeve-type radial bearing. The oil then gravitates from the bearing over the lower strut of the GG inlet casing into the lube oil tank. The line for lube oil supply to the GG rear bearing is connected to the lower GG main casing half in the rear area. The oil is injected in the same way as on the GG front bearing through a hose and internal ducts inside the gas generator. By gravitational force the oil flows into a collecting chamber and from there through a hose that is also inside the gas generator back into the lube oil tank. Details about the instruments on the GG bearings and on the rear GG bearing housing will be found in the description of the base engine instrumentation.

Version 02.2008

Base engine © MAN TURBO AG

2 | 13 - 22

Service and Maintenance Instructions for Gas Turbine

Lube oil connections on the gas generator

1

Oil feed

2

Oil return

Front bearing gas generator

Version 02.2008

Base engine 2 | 14 - 22

© MAN TURBO AG

2.2.4

1

Oil feed

6

Oil return

2

Carrier for labyrinth / floating ring seal

7

GG shaft

3

Backpressure bearing

8

Thrust collar

4

Sleeve bearing

9

Thrust bearing

5

Bearing support

Inspection measures V1, V2, V3, and V4 The gas generator components to be inspected during the scheduled inspection measures V1, V2, V3, and V4 are listed in the following table. For determination of the times of implementation, the equivalent operating hours shall be calculated according to Section 2.1.3 Calculation of equivalent operating hours [J 2 | 2] . Inspection measures for gas generator (part 1 of 2) Components to be checked

Point in time V1

V2

V3

V4

x

x

x

x

x

x

x

x

x

x

- front gearbox or inner shaft

x

x

- front bearing

x

x

- oil sealing ring and labyrinth seal

x

x

- inlet guide vanes

x

x

x

x

- upper main casing half

x

x

- upper stator blade carrier half

x

x

- clearances between rotor/stator blade carrier

x

x

- compressor rotor

x

x

Disconnection of the gas generator from the power turbine Air inlet elbow External inspection

x

x

Disassembly, inspection, and assembly Air inlet casing of compressor External inspection

x

x

Internal inspection Disassembly, inspection, and assembly of

Compressor Borescopic examination of stages 000 and 00 Axial displacement measurement of stages 000 and 00

x

Disassembly, inspection, and assembly of

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Base engine © MAN TURBO AG

2 | 15 - 22

Service and Maintenance Instructions for Gas Turbine Point in time - rear bearing

x

x

Inspection measures for gas generator (part 2 of 2) Components to be checked

Point in time V1

V2

x

x

V3

V4

Combustion chambers External inspection Borescopic and visual inspection Disassembly, inspection, and assembly of - flame tubes

x

x

x

- slide rings

x

x

x

- fuel nozzles

x

x

x

- igniters

x

x

x

- slide rings

x

x

- air manifold

x

x

- main casing, top part

x

x

- gas collector

x

x

x

x

- HP1 stator blades

x

x

- HP rotor

x

x

- HP2 stator blades

x

x

- replacement of HP1/HP2 honeycomb seals

x

x

Gas collector Borescopic and visual inspection

x

x

Disassembly, inspection, and assembly of

HP turbine Borescopic examination of HP1 stator blades Borescopic examination of HP rotor Checking of clearances between rotor and stator blade carrier

x

x x

Disassembly, inspection, and assembly of

2.3

Power turbine

2.3.1

Design and function of power turbine The LP turbine consists of one each ■ LP1 stator blade carrier, ■ LP2 stator blade carrier,

Version 02.2008

Base engine 2 | 16 - 22

© MAN TURBO AG

■ LP turbine rotor, ■ Main casing, ■ Exhaust elbow. The LP turbine is an axial-flow two-stage backpressure turbine which converts the energy contained in the exhaust gas from the gas generator into rotary movement and transfers it to the processing machine via the output coupling. 2.3.2

Modular design The following figure illustrates the modular structure of the LP turbine of a THM 1304 gas turbine unit with standard combustion chambers. The modular design of a THM permits the exchange of all modules inside the acoustic enclosure with only few equipment needed.

Modular design of the power turbine

2.3.3

1

LP1 stator blade carrier

4

LP turbine shaft

2

LP2 stator blade carrier

5

LP main casing

3

LP turbine rotor

LP1 stator blade carrier casing The gas generator is connected to the power turbine via the inlet flange of the single-part LP1 stator blade carrier. Eight thermocouples (T4) for monitoring the PT inlet temperature and the LP1 stator blades are arranged in the LP1 carrier.

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Base engine © MAN TURBO AG

2 | 17 - 22

Service and Maintenance Instructions for Gas Turbine

LP1 stator blade carrier casing

2.3.4

1

T4 thermocouple

3

2

LP1 stator blade carrier

LP1 stator blade

LP turbine rotor / LP2 stator blade carrier The LP2 stator blades are inserted in the two-part LP2 stator blade carrier. For inspection of the hot gas parts, one carrier half can be removed (after having shifted apart the gas generator and the LP turbine). The LP turbine rotor consists of two discs with the LP1 and LP2 rotor blades, inserted in fir-tree-shaped grooves. The pair of discs is connected to the LP shaft via four body-bound studs and four bolts. The shaft is connected to the output coupling which transmits the torque to the driven machine. Sealing of the LP turbine rotor is made by honeycomb seals. In the course of the first operating hours, the labyrinth strips mounted on the rotor blades and on the turbine disc work into the honeycomb seals. This

Version 02.2008

Base engine 2 | 18 - 22

© MAN TURBO AG

kind of sealing keeps the clearances and as such the performance and efficiency losses very low.

LP turbine rotor / LP2 stator blade carrier

2.3.5

1

LP2 stator blade carrier

3

LP turbine rotor with shaft

2

LP2 stator blade

4

Borescope port

Support of LP turbine rotor The LP turbine rotor is supported by two hydrodynamic tilting pad sleeve bearings the design and function of which is similar to that of the GG bearings. Contrary to the GG rotor, the axial thrust, axial backpressure and sleeve-type radial bearings are arranged at the rear shaft end.

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Base engine © MAN TURBO AG

2 | 19 - 22

Service and Maintenance Instructions for Gas Turbine

Sealing towards the LP turbine at the front end of the LP front bearing is effected via a floating ring which slides on the shaft end of the LP rotor and via a labyrinth seal. There is no sealing at the rear end of the LP front bearing. The cooling air from the space between the two LP turbine discs is used as seal air for the labyrinth seal. On the LP rear bearing a floating ring and/or labyrinth seal is not installed. Supply of lube oil to the two LP bearings is made through a line connected to the LP rear bearing housing. Part of the oil flows directly into the LP rear bearing while the remaining oil flows to the LP front bearing through an internal line connecting the two bearings. Oil injection in the bearing is made in the same way as on the GG bearings. The oil from the LP front bearing then gravitates into the internal casing of the LP main casing. Approximately half of the oil from the LP rear bearing also flows into the internal casing while the remaining oil flows into the coupling guard. The oil then returns through the line connected to the internal casing and/or to the coupling guard into the lube oil tank. The description of the base engine instrumentation includes information on the instruments that are installed on the bearings and/or the rear bearing housing.

Lube oil connections on the LP turbine

1

Oil feed

2

Version 02.2008

Base engine 2 | 20 - 22

Oil return

© MAN TURBO AG

Rear bearing power turbine

2.3.6

1

Bearing support

5

Sleeve-type radial bearing

2

Oil feed

6

LP shaft

3

Thrust bearing

7

Oil supply connection

4

Backpressure bearing

8

Oil supply line to the LP front bearing

Inspection measures V1, V2, V3, and V4 The LP turbine components to be inspected during the scheduled inspection measures V1, V2, V3, and V4 are listed in the following table. For determination of the times of implementation, the equivalent operating

Version 02.2008

Base engine © MAN TURBO AG

2 | 21 - 22

Service and Maintenance Instructions for Gas Turbine

hours shall be calculated according to Section 2.1.3 Calculation of equivalent operating hours [J 2 | 2] . Inspection measures for power turbine Components to be checked

Point in time V1

V2

V3

V4

x

x

x

x

Measurement of axial displacement

x

x

Checking of clearances between rotor and stator blade carrier

x

x

Disassembly, inspection, and assembly

x

x

Disassembly, inspection, and assembly of

x

x

- oil sealing ring and labyrinth seal

x

x

- LP turbine shaft

x

x

- front and rear bearing

x

x

x

x

x

x

x

x

LP1 stator blades Disassembly, inspection, and assembly LP2 stator blades Disassembly, inspection, and assembly LP turbine rotor

LP turbine shaft and bearings

Plate lining of LP casing Visual inspection Exhaust elbow External inspection

x

Disassembly, inspection, and assembly

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Base engine 2 | 22 - 22

x

© MAN TURBO AG

3

Instrumentation base engine

3.1

System-related information

3.1.1

Design and function The instrumentation of the base engine mainly comprises the speed, pressure, vibration, bearing wear, and temperature measuring devices which are installed on gas generator and power turbine and which are required on the one hand for control purposes and on the other hand for monitoring of the gas turbine.

Location of base engine measuring devices*

1

Drive coupling with gear wheel for speed measurement of GG rotor (in the case of units with mechanically driven main lube oil pump the GG speed sensors are located on the auxiliary gearbox.)

2

Front GG bearing with vibration measurement, keyphasor, bearing monitoring (temperature, wear)

3

Rear GG bearing with bearing temperature monitoring

4

PT inlet temperature measurement

5

Front PT bearing with bearing temperature monitoring

6

Rear PT bearing with vibration measurement, keyphasor, bearing monitoring (temperature, wear), speed measurement

*

The Figure shows a gas generator with standard combustion chambers. In the case of gas generators with DLN combustion chambers the measuring locations are the same as shown in the illustration.

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Instrumentation front GG bearing

1

Bearing wear sensors

2

Keyphasor

Instrumentation rear PT bearing

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3.1.2

1

Cables of vibration sensors arranged directly behind the speed sensors.

2

Speed sensors

3

Keyphasor

4

Bearing wear sensors

Safety information WARNING Hazard of personal injury and damage to property. Work on base engine components may only be carried out during standstill and after a cool-down period of several hours. Prior to performance of service and maintenance measures the following Sections shall be observed.

3.1.3

Inspection Routine inspections and walk-around checks have to be carried out regularly. Additionally, an annual major inspection of the described system is recommended.  Routine inspections / walk-around checks [J 1 | 19]  Checking of major functional component parts and protective

equipment [J 1 | 19] 3.2

Speed measurement (nGG, nPT)

3.2.1

Design and function The main components for speed measurement are 4 inductive speed sensors, and 2 overspeed protection relays installed in the GT control cabinet. The two speed sensors envisaged for monitoring the GG rotor are installed on the auxiliary gearbox. The two speed sensors envisaged for monitoring the PT rotor are installed in the rear PT bearing location. The speed sensors generate a frequency proportional to the number of impulses. In the case of the gas generator the impulses are generated by means of a gear wheel (number of teeth = 50) which is fixed to the auxiliary gearbox. In the case of the power turbine the impulses are generated by means of a shaft toothing (number of teeth = 60). Two speed signals are picked up for each rotor (GG, PT); one of these signals is processed by the GT control system and the other one by the overspeed protection relay. The sensor cabling is routed through a rib of the GG inlet casing or the PT main casing via a terminal box installed on the GT base frame to the GT control panel.

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Arrangement of GG speed sensors

1

Auxiliary gearbox

4

Cardan shaft

2

Fitting plates for GG speed sensors

5

Gas generator connecting flange

3.3

Inlet temperature measurement on power turbine (T4)

3.3.1

Design and function The main component parts of PT inlet temperature measurement are 8 double thermocouples, 10 temperature measuring transducers and one evaluation unit (component part of the GT controller). Measurement serves amongst others for monitoring the ignition process, for protecting the gas turbine unit against overfiring and for measuring individual and averaged values which are necessary for control of the gas turbine unit. Two thermal e.m.f's are generated for each thermocouple, one serves for determining the individual values and the other for average value generation. Average value generation is made by means of the temperature measuring transducers. Arrangement of the thermocouples in the LP1 stator blade carrier casing of the power turbine is shown in the figure below. There is a total of 12 ports in the LP1 casing; 4 of these are closed by blind flanges and are not identified by a number in the figure below.

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Arrangement of the T4 thermocouples (shown in the direction of flow)

Assembly location of a T4 thermocouple

1

T4 cable

4

LP1 casing

2

Thermocouple element

5

HP2 casing

3

Protection sleeve

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3.3.2

Exchange of T4 thermocouple NOTE Note concerning installation. When installing the T4 thermocouple take special notice of the groove in the thermocouple cartridge and the tongue of the T4 thermocouple which is visible when looking into the cap nut. The tongue and groove ensure that the openings in the area of the thermocouple tip point in the direction of flow and the T4 temperature can thus be measured correctly. Z Observe Section 3.1.2 Safety information [J 2 | 3] .

1. Loosen the cable ends of the T4 thermocouples to be exchanged in the terminal box. 2. Loosen the cap nut of the T4 thermocouple on the LP1 stator blade carrier casing. Note: The screws of the T4 protection sleeve need not be loosened. 3. Install the T4 thermocouple. 4. Tighten the cap nut. Note: Observe the tightening torque in Chapter “General service and maintenance information“. 5. Connect the cable ends of the T4 thermocouple in the terminal box.  Tightening torques for base engine connections [J 1 | 15]

3.4

Vibration measurement

3.4.1

Design and function 4 inductive proximity sensors (vibration pick-ups), 4 signal transducers and electronic cards are installed to monitor the vibrations of the GG and PT rotors. The two sensors for monitoring the GG rotor vibration are installed in the front GG bearing section and the PT vibration sensors in the rear PT bearing section (see figures in Section 3.1.1 Design and function [J 3 | 1] ). The sensor cabling is routed through a rib of the GG inlet casing and the PT main casing to the signal transducers. Due to the radial movement of the rotor the oscillating circuit created by the sensor coil is dampened considerably, i.e. the cyclic stress is greatly reduced. The generated negative voltage signal is proportional to the distance between sensor and shaft. The measured signals are transmitted by the signal transducers to the vibration monitor in the GT control cabinet where they are evaluated and indicated. If a limit value is exceeded, either an alarm is issued or tripping initiated.

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3.5

Phase angle measurement

3.5.1

Design and function Phase angle measurement comprises 2 keyphasor sensors, 2 signal transducers and, depending on the design, either 1 or 2 electronic card(s). One keyphasor each is located in the front GG bearing section and one in the rear PT bearing section (see figures in Section 3.1.1 Design and function [J 3 | 1] ). The sensor cabling is routed through a rib of the GG inlet casing and the PT main casing to the signal transducers. The electronic cards for evaluation are a component part of the vibration monitor which is installed in the GT control cabinet. The keyphasor is a position transducer or a capacitive proximity sensor which once every revolution generates a voltage signal via a square bar or pin fastened on the GG or PT shaft; this signal is transmitted to the vibration monitor via a signal transducer. The keyphasor signal serves for illustrating the relation between speed and vibration frequency.

3.6

Bearing temperature measurement

3.6.1

Design and function Bearing temperature measurement comprises 12 thermocouples and 6 temperature transducers. Each bearing is provided with 2 thermocouples; one of these is connected to a temperature transducer and the other - which is routed to the measuring transducer - serves as standby and is connected only in the event of failure of a thermocouple. The thermocouple is passed through a bore in the tilting pad of the bearing. Cabling of the thermocouples is routed through a rib of the GG inlet casing or the PT main casing to the GT control panel via terminal boxes.

3.7

Wear measurement on thrust bearing

3.7.1

Design and function Wear measurement on the thrust bearing comprises 4 capacitive proximity sensors and 4 signal amplifiers (proximitors). Two sensors each for monitoring axial wear on the thrust bearing are arranged in the front GG bearing section and in the rear PT bearing section (see figures in Section 3.1.1 Design and function [J 3 | 1] ). The sensor cabling is routed through a rib of the GG inlet casing and the PT main casing to the signal transducers. The electronic cards for evaluation are a component part of the vibration monitor which is installed in the GT control cabinet. Due to the axial movement of the rotor the oscillating circuit created by the sensor coil is dampened considerably, i.e. the cyclic stress is greatly

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reduced. The generated negative voltage signal is proportional to the distance between sensor and shaft.

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4

Fuel gas system

4.1

System-related information

4.1.1

Design and function The fuel gas system mainly comprises: trip and vent valves; fuel gas filter; monitoring instruments (e.g. for pressure, temperature, etc.) as well as one fuel gas metering valve. The fuel gas system operating in conjunction with the GT control system supplies the gas turbine with fuel gas during start-up and subsequent operation. Further, it warrants immediate isolation of fuel gas feed especially in the case of a trip (e.g. due to overtemperature and overspeed conditions or component malfunctions). The fuel gas flows through a fuel gas filter and trip valve(s) to the fuel gas metering valve. The fuel gas flow rate is regulated in line with the operating condition and the gas turbine power setting and routed to the two combustion chambers. In the event of a gas turbine unit trip, the fuel gas trip valve is closed, the vent valve is opened and the fuel gas present in the pipes is discharged through vent pipes.

4.1.2

Fuel gas specification

4.1.2.1

General This fuel gas specification defines the requirements for gaseous fuels to be used in THM gas turbines. Natural gases with a methane content of more than 80% by volume are used by preference. Generally, the limit values for physical and chemical properties listed in the table below have to be adhered to. Gaseous fuels which do not correspond to the limit values given in the table may possibly be approved for THM gas turbines nonetheless. For this, however, the technical department of MAN TURBO AG has to make a detailed assessment of these values. By special protective measures carried out on gas turbine components it may become permissible to exceed individual limits. In the case of gas turbines which are equipped with Dry-Low-NOx (DLN) combustion chambers further limit values have to be observed to ensure trouble-free operation. When assessing the gas analysis especially those substances have to be considered which can lead to corrosion, e.g. alkaline metals (sodium, potassium, etc.) or sulphur compounds so that adequate steps can be taken for minimising corrosion in the gas turbine or the fuel system. In addition to assessment of the gas analysis and of impurities contained in the fuel gas envisaged for operation customer is urgently recommended to set up a suitable system for fuel supply and conditioning as well as for monitoring the fuel gas quality.

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The table specifies limit values for the concentration of various impurities. Further possible sources of impurities are the inlet air, and, if applicable, the water which is injected into the combustion chamber. The limit values in the table are valid on the assumption that additional impurities will not be added through air or water. If, however, this should be the case, the limit values for fuel gas have to be reduced for each component as shown in the following formula:

Cmax,corrected = Cmax, table - AFR x Cair - WFR x Cwater

4.1.2.2

Cmax,corrected

=

Corrected max. permissible concentration

Cmax, table

=

Maximum permissible concentration from the table

Cair

=

Expected concentration in the air

Cwater

=

Expected concentration in the injection water

AFR

=

Mass flow ratio air to fuel (typically approx. 60 : 1)

WFR

=

Mass flow ratio injection water to fuel (typically 0.5 - 1.0 : 1)

Minimum physical and chemical properties profile of gaseous fuels Fuel gas properties Property

Limit value

Lower heating value (LHV)

31 - 48 MJ/mN3 *)

Wobbe Index (Note 1)

40 - 53 MJ/mN3 *)

Admissible fluctuation of heating value and Wobbe Index with set control

Test method

± 10%

Methane content (CH4)

min. 80% by vol. (only DLN)

Content of hydrocarbons C3 or heavier

max. 4.0 vol.-% (only DLN)

Hydrogen content (H2)

max. 1.0 vol.-% (only DLN) max. 60 vol.-% (standard combustion chamber)

Ratio between upper and lower quenching limit (at 101.3 kPa, 25°C)

min. 2.2 (only DLN)

Water content (H2O)

(Note 2)

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Property Dust particle impurities:

Limit value

Test method

max. 20 ppm wt

ISO 3735

Particle diameter > 10mm Particle diameter 2 - 10mm

0 vol.-% 10 vol.-%

Impurities with corrosive effect : Total sulphur content

max. 100 ppm vol. (without special coating)

ISO 8754

max. 1.5 vol.-% (with special coating in the turbine section) (Note 3) Sodium + potassium

max. 0.5 ppm wt

DIN 51797

*) mN³ referred to standard conditions (0°C, 101.3 kPa)

Note 1 Wobbe Index (corrected to 15°C) =

T = Fuel gas temperature [°C] d = ratio of standard density of fuel gas to standard density of air Hu = lower heating value [MJ/Nm³] Note 2 The water content must not exceed a max. concentration during which gas hydrates might develop immediately upstream the fuel gas control valve, taking into consideration the fuel gas temperatures, pressures, and compositions which are possible during operation. Gas hydrates are not allowed. Heating up of the fuel is permissible. Note 3 Sulphur dioxide (SO2) develops through combustion of sulphur compounds in the fuel gas. The total sulphur content must therefore be limited to such an extent that compliance with the emission limit values specified by the local approval authorities is ensured. Among other elements, the total sulphur contains hydrogen sulphide (H2S), mercaptan, carbon disulphide (CS2), carbonyl sulphide (COS), thiopenes and sulphur oxides.

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Service and Maintenance Instructions for Gas Turbine

4.1.2.3

Fuel gas pressure The following table contains limit values which have to be maintained at the inlet of the fuel gas control valve, i.e., downstream of the gas pressure control unit. Fuel gas pressure at the inlet to the fuel gas control valve Property

Limit value

Test method

Minimum fuel gas inlet pressure (Note 4) : THM 1203

approx. 1.5 MPa (absolute)

THM 1304-10

approx. 1.8 MPa (absolute)

THM 1304-11

approx. 2.0 MPa (absolute)

Maximum admissible fuel gas inlet pressure

3.1 MPa (absolute)

Acceptable pressure variation

± 2,5%

DIN 3380

Acceptable hysteresis of fuel gas pressure

4%

DIN 3380

Admissible deviation of fuel gas pressure from set-point value at minimum flowrate

15%

Admissible transient pressure change

max. 0.2 bar/s

Note 4 The minimum fuel gas inlet pressure given in the table refers to ISO conditions (15°C air inlet temperature, sea level, no pressure losses). The fuel gas inlet pressure required in each respective case depends on the installation and operating conditions and also on the fuel gas composition. Calculation for a specific project can be made by MAN TURBO AG. 4.1.2.4

Fuel gas temperature (gas turbine inlet) Liquid constituents in the fuel gas are not allowed. The min. temperature must be 20 K above the dew point of heavy hydrocarbons and 20 K above the dew point of water. Limit values for the fuel gas temperature Property

Limit value

Minimum fuel gas temperature

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0°C

© MAN TURBO AG

Property

Limit value

Maximum dew point temperature

50°C

Maximum fuel gas temperature

70°C *)

Admissible transient temperature change

max. 4 K/min

*) With minor modifications to the fuel gas system 90°C are also acceptable.

4.1.3

Safety information WARNING Hazard of personal injury and damage to property! The service and maintenance work described for the fuel gas system can only be carried out with the gas turbine unit at standstill and cooled down. Where work can be carried out during ongoing operation (e.g. work on a change-over type filter) a note is added under the relevant component description. For safety reasons the components of the fuel gas system must not be dismantled and repaired at site but only in an authorized workshop. Prior to performance of service and maintenance measures the following Sections shall be observed.

4.1.4

Service and maintenance The service and maintenance intervals have to be determined by the Operator / User by reference to the operating conditions such as medium / temperature / degree of fouling / environmental effects / operating cycle, etc. MAN TURBO AG recommend a 2-year interval for the performance of inspection, maintenance, and possibly repair work. U CAUTION Warning of pressurized media! Before start of work make sure that the operating system is isolated and that the section to be inspected has been drained, or, in the case of gas systems, has been adequately inertized. The safety shut-off facilities with bellows seal on the spindle or automatic sealing set with subsequent additional O-ring or grooved ring seal are designed for maintenance-free operation. Owing to the encapsulated design there is no access from the spindle guide towards the outside, so that readjustment (such as in the case of stuffing box packings) is excluded and constant frictional forces are maintained for a safe operating mode. Checking of the spindle seal for external tightness (bellows or automatic sealing set) can be made at the test connection provided for this purpose

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Service and Maintenance Instructions for Gas Turbine

(see following figure) by brushing with Nekal; this should be done at specified time intervals during the walk-around checks. In case of even minor leakage the damage must be eliminated at the earliest possible opportunity by personnel at site or by the manufacturer. Operation can be maintained for a short period only by plugging the test connection (G1/8“). Any sealing of the guides of movable parts through stuffing boxes adjustable by hand is not permitted for safety shut-off facilities according to the applicable standards for component testing. Testing of internal tightness – valve seal on the seat of a single trip valve – can be made based on the pressure drop or pressure rise method. For this, appropriate shut-off valves and measuring connections must be available. Testing of internal tightness – valve seal on the seat, in the case of gas trip combinations on the burner – can be made as follows after venting the space between the two valves: a) By means of an optical leakage check facility downstream of the intermediate vent valve (float or bubble vessel with water fill). During this test with gas pressure applied, only the first valve in flow direction is checked for leak proofness. b) By an automatic leakage check facility (interrogated via pressure monitor). During this test with gas pressure applied, both valves are checked for leak proofness according to the pressure rise / pressure drop method. In case of a leakage, start-up of the burner is prevented by the electric interlock in the safety chain. In such a case the damage has to be corrected immediately by the maintenance personnel or by the manufacturer. On safety shut-off facilities service and maintenance has to be carried out by the manufacturer after an operating period of 2 – 3 years at the latest. In the course of this work damaged parts are replaced and signs of wear are assessed for determining whether continued use of the safety shut-off facilities is possible. All elastomers must be replaced after 5 years at the latest (limited by the manufacturer guarantee for elastomers). This is also necessary if the safety facility was not actually used in operation. The same conditions apply to mounted control parts – especially the solenoid control valves. During revision of the solenoid valves, disassembly shall be carried out on a spot-check basis so that wear parts and cleanliness of the control air system can be assessed. During maintenance of the valve actuators the cylinder tube and the spindle guides/seals shall be lightly greased prior to assembly. The recommended lubricant is silicone paste, e.g. Gleitmo 750.

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ATTENTION Risk of malfunctions! Following the performance of service and maintenance measures, proper functioning has to be rechecked as described above prior to re-starting; component parts designed for signalling (e.g. limit switches) may have to be readjusted.

Test connection on trip / vent valve

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Service and Maintenance Instructions for Gas Turbine

4.1.5

1

Venting

3

2

Instrument air connection

Test connection

Inspection Routine inspections and walk-around checks have to be carried out regularly. Additionally, an annual major inspection of the described system is recommended.  Routine inspections / walk-around checks [J 1 | 19]  Checking of major functional component parts and protective

equipment [J 1 | 19] 4.1.6

Repair General information relating to the replacement of components (e.g. pressure switches, pressure sensors, limit switches, thermometers, pressure gauges, valves, etc.) not included in the present system description will be found in Chapter "General service and maintenance information". Should any further information be required, please contact the MAN TURBO AG After Sales Service.  General notes on the exchange of component parts [J 1 | 5]

4.2

Job-specific and system-related documents

4.2.1

Drawings Drawings (as far as listed in the following) are filed in the printed documentation in folder “Drawings“.

4.3

Fuel gas metering valve

4.3.1

Design and function The fuel gas metering valve (see illustration below) installed inside the acoustic enclosure serves on the one hand for the supply of ignition gas to the igniters and on the other hand for control of the fuel gas mass flow during load operation of the gas turbine. With reference to the GT performance set by the operator a stepping motor is actuated amongst others by the GT control system and the fuel gas metering valve is adjusted accordingly. The fuel gas metering valve is a compact unit comprising the actual metering valve, a stepping motor, limit switches, solenoid valves and a pressure limiting and trip valve. During the ignition cycle, the fuel gas flows into the fuel gas metering valve, and then via the ignition gas pressure limiting valve and the ignition

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gas solenoid valve to the two igniters in the combustion chambers. In order to prevent the fuel gas from flowing to the fuel nozzles during initiation of the ignition cycle, the metering valve, the solenoid valve and the trip valve are closed. The spark plugs ignite the air/fuel gas mixture flowing out of the igniters. The solenoid valve is then energised to open. This causes the trip valve located downstream of the metering valve to also open. If the trip valve has not opened, the limit switch initiates tripping of the gas turbine. Actuation of the stepping motor opens the fuel gas metering valve, allowing fuel gas to flow to the two fuel nozzles of the combustion chambers where it is mixed with compressor air and ignited. Following successful completion of the ignition cycle, the ignition gas solenoid valve is closed. The actual position of the metering valve detected by the repeater is processed by the GT control system. Under certain operating conditions a limit switch initiates an alarm if the metering valve is not closed. During the purging process or following a trip, the fuel gas remaining in the fuel gas metering valve is discharged through a vent line into the atmosphere via the solenoid valves and a pipe connected to the trip valve. For calibration, switches are provided on the GT control panel for manual actuation of the fuel gas metering valve. During calibration, the position of the valve can be read from a scale directly fitted on the valve.

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Service and Maintenance Instructions for Gas Turbine

Fuel gas metering valve

1

Terminal box

6

Solenoid pilot valve for trip valve

2

Repeater

7

Stepping motor

3

Ignition gas release valve connection *

8

Terminal box

4

Vent port

9

Trip valve

5

Vent valve

10

Compensation connection

*

The Figure shows a dummy flange instead of the ignition gas release valve.

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4.4

Fuel gas filter

4.4.1

Subcontractor documentation The subcontractor documents are filed in the printed documentation in folder “Operating Instructions for Components“.

4.4.2

Drawings Drawings (as far as listed in the following) are filed in the printed documentation in folder “Drawings“.

4.5

Trip valve

4.5.1

Design and function The fuel gas system of the gas turbine is equipped with a pneumatically operated trip valve (for number of installed trip valves refer to the instrument list and to the P&I diagrams). In the event of a trip of the gas turbine unit, it immediately shuts off the fuel gas supply to the fuel gas metering valve and thus to the combustion chambers of the gas turbine. The valve position is monitored by limit switch. The trip valve is actuated by instrument air. For safety reasons failure of the instrument air supply results in immediate closing of the trip valve with simultaneous opening of the fuel gas vent valve as well as tripping of the gas turbine unit. A solenoid valve is provided for trip valve activation.

4.6

Vent valve

4.6.1

Design and function The fuel gas accumulating during depressurisation of the fuel gas system on shutdown of the gas turbine is conveyed to the atmosphere via a pneumatically operated vent valve (for the number of installed vent valves refer to the instrument list and to the P&I diagrams) and the associated piping. The valve position is monitored by limit switch. A solenoid valve is provided for actuation of each vent valve.

4.7

Pressure transducer

4.7.1

Subcontractor documentation The subcontractor documents are filed in the printed documentation in folder “Operating Instructions for Components“.

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5

Ignition system

5.1

System-related information

5.1.1

Design and function The main components of the ignition system comprise two igniters and two high-voltage ignition transformers. One igniter each is fitted laterally in the combustion chamber casing. The ignition transformers are installed in a casing which is located to the right of the gas generator (view in direction of flow). The ignition system is designed for igniting the fuel/air mixture in the two combustion chambers during the start-up process of the gas turbine.

5.1.2

Safety information WARNING Hazard of personal injury and damage to property! The service and maintenance measures described in the following must only be performed with the gas turbine unit at standstill and cooled down. Prior to the exchange of any components, the ignition system must be safely isolated from the supply voltage. If this is not observed, there is the risk of an electric shock owing to the extremely high voltage. Work on the ignition system may be carried out at the earliest 30 minutes after voltage supply has been discontinued to permit the stored charge to decay. Prior to performance of service and maintenance measures the following Sections shall be observed.

5.1.3

Inspection Routine inspections and walk-around checks have to be carried out regularly. Additionally, an annual major inspection of the described system is recommended.  Routine inspections / walk-around checks [J 1 | 19]  Checking of major functional component parts and protective

equipment [J 1 | 19] 5.1.4

Ignition test For checking proper functioning of the ignition system a program sequence is envisaged which can be selected via button "ignition test" on the GT control panel. The following sequence description is based on a

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fuel gas system with two vent and trip valves. The sequence is identical for plant units with just one vent and trip valve. For initiating the sequence the following steps have to be carried out: 1. Observe the general safety information given in the system description. 2. Actuate button "ignition test". 3. Actuate button "... start-up preparation". 4. Actuate button "… pressurization" (only for plant units with compressor). 5. Actuate button "… start". Note: When purging for the removal of gas residues from the gas turbine interior has been carried out, the following sequence steps are initiated for checking proper functioning of the ignition system. 6. The instrument air solenoid valves are changed over and the vent and trip valves opened. For approx. 10 to 30 seconds gas flows through the vent valves for purging impurities (especially condensate) from the fuel gas piping. 7. The instrument air solenoid valves for activation of the two vent valves are changed over and the vent valves are closed. 8. The ignition transformers for supply of the ignition electrodes are cut in. 9. The fuel gas control valve is opened. The fuel gas flows to the ignition electrodes. In the area of the ignition electrodes the fuel gas is mixed with compressor air and ignited. 10. Proper functioning of the ignition system can be assessed by reference to the slight rise in the T4 temperature (approx. 5 to 8°C / 41 to 46.4°F) or to the noise developed by the ignition transformers. 11. The ignition test is complete when the fuel gas trip valves close, the fuel gas vent valves open, and the ignition transformers are cut out. 12. Unless the gas turbine is then stopped and button "ignition test" actuated once more, the start-up procedure is continued with repetition of the purging operation. 13. If ignition problems should still occur, please contact the Service Department of MAN TURBO AG. 5.1.5

Repair General information relating to the replacement of components (e.g. pressure switches, pressure sensors, limit switches, thermometers, pressure gauges, valves, etc.) not included in the present system description will be found in Chapter "General service and maintenance information". Should any further information be required, please contact the MAN TURBO AG After Sales Service.  General notes on the exchange of component parts [J 1 | 5]

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5.2

Ignition transformer

5.2.1

Design and function The two ignition transformers are installed in a casing next to the gas generator. The ignition transformers are connected to the igniter spark plugs through the ignition cables and supply the spark plugs with a voltage of approx. 2,000 V.

Design of ignition transformers

5.2.2

Replacement Z Observe the general safety information given in the system description.

1. Open the ignition transformer casing. 2. Disconnect the wiring from the ignition transformer to be replaced and mark the cables, if necessary. 3. Exchange the ignition transformer. 4. Connect the cables. 5. Tighten the screw fitting on the ignition transformer casing. 6. Carry out an ignition test.

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Service and Maintenance Instructions for Gas Turbine

5.3

Igniters

5.3.1

Design and function The igniters which are fitted laterally into the combustion chamber casings consist of a double-wall casing with screwed-in fuel nozzle and spark plug. The casing is equipped with a connection for supply of the fuel nozzle with fuel gas. Compressor air and fuel gas enter the interior of the igniter casing through bores and slots. It is here that mixing and ignition take place.

Location and design of the igniter

1

Spark plug

4

Compressor air supply

2

Liquid fuel supply*

5

Fuel gas supply

3

Igniter

*

In units operated on fuel gas, the liquid fuel supply connection is closed by means of a plug screw.

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6

Guide vane actuator

6.1

System information

6.1.1

Design and function The main components of the guide vane positioning system include the GG compressor inlet casing with 18 movable inlet guide vanes, a positioning mechanism and an electrically driven servo motor as well as a positioner. The first stator blade / guide vane row of the GG compressor on the THM 1304 is of adjustable design in order to allow control of the air flow rate (especially during start-up and rundown as well as during turndown). This control feature makes it possible to achieve an optimum GG compressor efficiency throughout the total speed range. Above that, a favourable air/fuel ratio is ensured and compressor surging avoided. Positioning of the guide vanes is made as a function of the GG speed via the gas turbine control system. The actual position of the inlet guide vanes detected by a position sensor is processed in the GT control system.

Guide vane positioning mechanism

1

Limit switch

3

Protective sheathing

2

GG compressor inlet casing

4

Actuator

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6.1.2

Diagram guide vane angle vs. GG speed

Diagram guide vane angle vs. GG speed

A

Guide vane angle

B

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ISO corrected GG speed

© MAN TURBO AG

6.1.3

Safety information WARNING Hazard of personal injury and damage to property. The service and maintenance measures described in the following must only be performed with the gas turbine unit at standstill and cooled down. Prior to performance of service and maintenance measures the following Sections must be observed.

6.1.4

Maintenance Service and maintenance work on the guide vane positioning system must only be carried out by appropriately trained and authorized personnel. Following exchange of the servo motor, the guide vane positioning system has to be calibrated.

6.1.5

Inspection Routine inspections and walk-around checks have to be carried out regularly. Additionally, an annual major inspection of the described system is recommended.  Routine inspections / walk-around checks [J 1 | 19]  Checking of major functional component parts and protective

equipment [J 1 | 19] 6.2

Position sensor

6.2.1

Design and function The position sensor installed on the GG compressor inlet casing (in 1 o’clock position) serves for detection of the actual position of the inlet guide vanes. The stem of the electromechanical position sensor is directly connected to one of the inlet guide vanes. Movement of the inlet guide vane simultaneously initiates rotation of the stem. On the one hand, the position of the guide vane is locally indicated on a scale and on the other hand transmitted to the GT control system via the measuring sensor installed in the head of the position sensor. The position sensor is equipped with a heat shield to protect it from heat radiation. In addition, an instrument air line is directed to the position sensor for cooling.

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Location and design of position sensor

1

Measuring value sensor

4

Inlet guide vane

2

Heat radiation shield

5

mech. position indicator

3

GG compressor inlet casing

6.3

Switch - Calibration of guide vane positioning system

6.3.1

Design and function By means of a switch which is installed on the GT control panel, the guide vane positioner can be switched over from automatic to manual mode for calibration of the system and for cleaning the GG compressor. Two other switches are provided on the GT control panel for fully opening or fully closing the inlet guide vanes after change-over to manual mode.

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ATTENTION Risk of damage to the gas turbine unit! Change-over to the manual mode may only be performed with the plant unit at standstill and exclusively for test and calibration purposes. This work may only be carried out by appropriately trained and authorised personnel.

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7

Blow-off and instrument air system

7.1

System-related information

7.1.1

Design and function

7.1.1.1

Blow-off system The blow-off system prevents surging of the compressor such that particularly during start-up, shut-down and part-load operations compressor air is discharged via blow-off valves from the third, sixth and last (radial) compressor stages into the atmosphere via headers connected to the exhaust duct. In addition, two pressure sensors are dedicated to the blow-off system for monitoring the compressor discharge pressure and the PT inlet pressure. A total of five blow-off valves (1 x 3rd stage, 2 x 6th stage, 2 x radial stage) is fitted to the front of the GG main casing. During normal GT operation, compressor air is taken from the radial stage and routed through pipes into the control chamber of the blow-off valves in order to keep them closed. One solenoid valve each is provided for activating each blow-off valve. If the GG rotor reaches the (ISO-corrected) speeds indicated in the following Table, power supply to the solenoid valve is switched on or off as required, thus adjusting the air supply to the valve control chamber. The gas turbine is monitored for surges by means of a differential pressure sensor. The two measuring lines are installed at two different locations on the intake elbow. Further information relating to this measurement is provided in the description of the intake air filter system. ATTENTION Risk of damage to the gas turbine! If a surge is detected, the gas turbine is tripped for safety reasons. The gas turbine may only be started up again after the cause of the surge has been investigated and remedied. Position of blow-off valves Valve

Blocked position

Flow position

rpm (GG speed, ISO-corrected) 3. stage

10,100

10,100

6. stage

10,100 10,700

10,000 10,600

Radial stage

9,500 9,750

9,400 9,650

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Arrangement of the blow-off valves*

7.1.1.2

1

Blow-off valve, stage 3

3

Blow-off valves, radial stage

2

Blow-off valves, stage 6

*

The Figure shows a gas generator with standard combustion chambers. The arrangement of the blow-off valves is identical for gas generators with DLN combustion chambers.

Instrument air system The instrument air system supplies the necessary compressed air for closing the blow-off valves during GT compressor cleaning and in this way prevents draining of cleaning fluid via the blow-off valves. Before the GT compressor cleaning operation is carried out, the instrument air system must be connected to the piping of the blow-off system by using hoses. Further information relating to these measures and to the cleaning operation will be found in the description of the cleaning system.

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7.1.2

Safety information WARNING Hazard of personal injury and damage to property. The service and maintenance measures described in the following must only be performed with the gas turbine unit at standstill and cooled down. Prior to performance of service and maintenance measures the following Sections must be observed.

7.1.3

Inspection Routine inspections and walk-around checks have to be carried out regularly. Additionally, an annual major inspection of the described system is recommended.  Routine inspections / walk-around checks [J 1 | 19]  Checking of major functional component parts and protective

equipment [J 1 | 19] 7.1.4

Repair General information relating to the replacement of components (e.g. pressure switches, pressure sensors, limit switches, thermometers, pressure gauges, valves, etc.) not included in the present system description will be found in Chapter "General service and maintenance information". Should any further information be required, please contact the MAN TURBO AG After Sales Service.  General notes on the exchange of component parts [J 1 | 5]

7.2

Blow-off valves

7.2.1

Design and function The five blow-off valves are almost identical in design. Some of the valves are, however, additionally equipped with a spring ( 4 ) or with different valve plugs ( 5 ). The spring which is installed in the blow-off valves of stages 3 and 6 supports complete opening of the valve. A shoulder on the valve plug of the blow-off valves of stage 6 and of the radial stage reduces the cross-section of the valve and as such the outgoing air flow (stage 6 to 50% and radial stage to 60% for each valve). The compressor air taken from the radial stage is routed via a port ( 1 ) into the control chamber of the blow-off valves. The valve stem which is connected to a rubber diaphragm is forced down keeping the valve closed. If air supply to the control chamber is interrupted by closing of the associated solenoid valve, the valve is opened by the compressor air

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Service and Maintenance Instructions for Gas Turbine

acting on the valve plug. When the gas turbine is at a standstill, the valve is kept open by the diaphragm (with some support by the spring).

Design of blow-off valve

7.2.2

1

Compressor air (radial stage)

4

Spring

2

Diaphragm

5

Valve plug

3

to the atmosphere

6

from the compressor

Replacement ATTENTION Risk of damage to the gas turbine! As the blow-off valves are of identical appearance on the outside, special care must be taken to ensure that the correct valve is installed. Refer to the spare parts catalogue for unambiguous identification. Installation of a blow-off valve at the wrong location can lead to gas turbine damage. Z Observe the general safety information given in the system description.

1. In view of its weight, the blow-off valve to be removed must be suspended from the acoustic enclosure crane using a suitable hemp rope.

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2. Loosen the screw connections on the blow-off valve (piping, GG main casing). 3. Use the enclosure crane to handle the defective and the new valve. 4. Apply graphite paste Never-Seez to the blow-off valve fastening bolts. 5. Use new seals when screwing down the blow-off valve. 6. Note: Observe the "Tightening torques for base engine connections" in Chapter “General service and maintenance information“. 7.3

Solenoid valves (for activation of blow-off valves)

7.3.1

Design and function The electrically actuated and directly controlled 3/2-way solenoid valves are provided for activating the blow-off valves. Activation of the solenoid valves is made as a function of the GG speed. The solenoid valves are mounted on a rack inside the acoustic enclosure on the right-hand side (view in direction of flow) next to the GG inlet casing.

Ports on the solenoid valve

1

Port 1: Control chamber vent

2

Port 2: To control chamber of blow-off valve

3

Port 3: From compressor (radial stage)

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7.4

Pressure sensors compressor discharge pressure / PT inlet pressure

7.4.1

Design and function The pressure sensors for measuring and monitoring the compressor discharge pressure (P2) and the PT inlet pressure (P4) are dedicated to the blow-off and instrument air system. The pressure sensors are mounted on the instrument rack which is located in the right-hand front area of the acoustic enclosure (view in direction of flow). For further details refer to the instrument list.

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8

Drainage system

8.1

System-related information

8.1.1

Design and function The drainage system mainly consists of three pneumatically operated drain valves and a drainage vessel. The valves are connected to the intake elbow, to the GG main casing, and to the exhaust elbow. The drain valves are kept in closed position during GT operation by GG compressor air. The valves are open during start-up, post-lubrication, standstill and/or the cleaning process. The lube oil or waste water drained through the valves is routed to a drainage vessel. Disposal of the liquid accumulating there must be carried out properly in compliance with the laws applicable at the site location. U CAUTION Fire hazard! Should lube oil escape during start-up or post-lubrication from one of the drain valves connected to the inlet bend and to the GG main casing, the gas turbine unit must not be started until this malfunction has been eliminated. While the oil mist separator is not in operation during the start-up process or during the post-lubrication phase or if the separator is not functioning properly there is an increased risk of lube oil penetrating through the bearings into the gas turbine and being ignited there. Oil residues outside the bearing locations must therefore be carefully removed and proper functioning of the oil mist separator ensured at all times.

8.1.2

Safety information U CAUTION Hazard of injuries! Except for evacuation of the drainage vessel or of the foundation pit, work on the drainage system can only be carried out with the gas turbine at standstill. Work inside the acoustic enclosure may only be carried out after an adequate cooling-down period. Prior to performance of service and maintenance measures the following Sections must be observed.

8.1.3

Inspection Routine inspections and walk-around checks have to be carried out regularly. Additionally, an annual major inspection of the described system is recommended.

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Service and Maintenance Instructions for Gas Turbine  Routine inspections / walk-around checks [J 1 | 19]  Checking of major functional component parts and protective

equipment [J 1 | 19] 8.1.4

Repair General information relating to the replacement of components (e.g. pressure switches, pressure sensors, limit switches, thermometers, pressure gauges, valves, etc.) not included in the present system description will be found in Chapter "General service and maintenance information". Should any further information be required, please contact the MAN TURBO AG After Sales Service.  General notes on the exchange of component parts [J 1 | 5]

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9

Cleaning system

9.1

System-related information

9.1.1

Design and function The main components of the cleaning system include the offline cleaning nozzles (4 off) located in the GT intake elbow which are interconnected through a ring line, and a mobile cleaning unit. In addition to the cleaning nozzles, two nozzles for the injection of a preservation fluid are installed in the intake elbow. Since dry air preservation is preferable to wet preservation, the preservation nozzles are not used any longer. The cleaning system serves to clean the gas generator interior. Impurities deposited on the blades are removed by regular cleaning, counteracting deteriorations in the performance and efficiency of the gas turbine unit. Above that, frequent compressor cleaning reduces the risk of corrosion damage and also the fuel consumption. The performance level and the efficiency of a gas turbine unit in the asnew state can, however, not be regained by cleaning because of the normal wear resulting from operation (e.g. in the area of seals and blades). The original level can only be restored by extensive works repair measures. For information about the expected course of deterioration of efficiency and performance refer to the diagrams / curves in the Operating Instructions.

9.1.2

Time of cleaning The time of cleaning depends on the site conditions and the associated soiling as well as on the operational experience. Above that, the time of cleaning depends on the extent of performance deviation which, as a rule, is indicative of soiling of the gas generator compressor. We recommend to initially clean the gas generator at least once a month. For determination of the site-specific cleaning interval, the performance shall be recorded before and after cleaning at comparable suction temperature and comparable suction pressure. If the improvement in performance after cleaning should only be slight, the cleaning interval may be extended. If the improvement in performance is significant, the cleaning interval has to be shortened appropriately. With a high salt content in the intake air, daily cleaning is recommended. If continuous operation does not allow this, cleaning is required at least once per week. This also applies if the unit has not been in operation before. Cleaning of the gas generator compressor is also required prior to long standstill periods for removing corrosive deposits.

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Service and Maintenance Instructions for Gas Turbine

9.1.3

Use of cleaning additives Cleaning additives have to be used for improving the cleaning efficiency, especially in the case of oily deposits and deposits insoluble in water. No other than the cleaning additives approved by MAN TURBO AG may be used (see Section 9.1.6.3 Approved cleaning additives [J 9 | 4] ). U CAUTION Hazard to health from cleaning additives! In order to avoid hazards to the health of personnel, the safety instructions by the respective cleaning additive supplier must be observed. For preparation and processing of the cleaning solution, the information provided by the supplier of the cleaning additive shall be observed.

9.1.4

Use of antifreeze

9.1.4.1

Risk of frost during cleaning In order to avoid freezing of the pumps and lines during cleaning when there is a risk of frost, isopropyl alcohol (IPA) or ethylene glycol shall be added to the cleaning solution or to the wash water. The following table is based on a mixing ratio of 1 : 4 (cleaning additive / water). Mixing ratios

°C

°F

Cleaning additive % vol

above +5

above 41

20

80 / 0

80 / 0

+5 to -5

41 to 23

20

60 / 20

60 / 20

-5 to -20

23 to -4

20

30 / 50

40 / 40

-20 to -30

-4 to -22

20

10 / 70

30 / 50

-30 to -40

-22 to -40

20

---

20 / 60

Ambient temperature

Water/IPA % vol

Water/glycol % vol

ATTENTION Performance losses and damage to the blading! Icing on the blades from frozen cleaning solution or wash water may result in performance losses and damage to the blading! 9.1.4.2

Risk of frost after cleaning In order to avoid freezing of the cleaning system after cleaning, all water lines and components of the cleaning system have to be drained. For this, the hand shut-off valves which must be kept closed during the cleaning phase have to be opened. During standstill of the cleaning system the

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valves of this system must be kept open, to ensure that water which might possibly freeze does not remain in the system. 9.1.5

Cleaning sequence After the gas turbine has cooled down (PT inlet temperature T4 < 65°C) and the preparatory measures have been completed, the following cleaning sequence steps may be initiated via the control panel on the GT control cabinet. Step 1:

Injection of cleaning solution with subsequent soaking.

Step 2:

Injection of clear water for flushing out the cleaning solution.

Step 3:

Ventilation of gas turbine for drying the internals.

Step 4:

15-minute load operation for drying the internals.

The cleaning sequence (steps 1 to 3) is basically a start-up process, but without the ignition being cut in and with the inlet guide vanes fully open. Above that, the blow-off valves are kept closed by instrument air instead of GG compressor air. Depending on the degree of soiling, steps 1 and 2 have to be repeated several times. 9.1.6

Wash water specification / approved cleaning additives

9.1.6.1

Scope This specification stipulates the approved cleaning additives and the requirements concerning the minimum properties profile of the wash water used for cleaning the gas generator compressor in gas turbine units of MAN TURBO AG.

9.1.6.2

Minimum properties profile of wash water Fully demineralized water (deionate) of high-purity should be used for cleaning the gas generator compressor in order to avoid corrosion and erosion. Since full compliance with these stringent quality requirements is often difficult to achieve at the installation site, the following water parameters are regarded as being still tolerable. Physical and chemical minimum properties profile of the wash water Property

Limit value

Unit

pH value at 20°C

6.5 to 8.5

pH

Conductivity at 20°C

≤ 50

µS/cm

Chlorides

≤ 10

mg/l

Sulphates

≤ 10

mg/l

Total hardness

≤1

mg CaO/l

SiO2 content

≤1

mg/l

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9.1.6.3

Property

Limit value

Unit

Total dissolved solids

≤ 30

mg/l

Solid foreign matter

≤5

mg/l

Approved cleaning additives The following cleaning additives may be used for online as well as offline cleaning: ■ Turbo-K ■ ZOK 27 Information about procurement of these products is available from the competent After Sales Service department of MAN TURBO AG.

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9.1.7

Safety information WARNING Hazard of personal injury and damage to property. Cleaning of the gas generator compressor may be carried out only with the gas turbine unit cooled down. In order to avoid hazards to the health of personnel, the safety instructions by the respective cleaning additive supplier must be observed. At ambient temperatures below +5°C (41°F) an antifreeze must be used. The pump of the mobile cleaning unit must not on any account be run without water - not even for checking. The service and maintenance measures described in the following must only be performed with the gas turbine unit at standstill and cooled down. Prior to the performance of service and maintenance work observe the following Sections.

9.1.8

Measures to be taken before initiating the cleaning sequence U CAUTION Warning of hazard to health! Cleaning of the gas generator compressor may be carried out only with the gas turbine unit cooled down. Hazard of burns! In order to avoid hazards to the health of personnel, the relevant safety information by the respective cleaning additive supplier and the references included in Chapter "General safety information" shall be observed. ATTENTION Risk of damage to plant unit components! At ambient temperatures below +5°C (41°F) an antifreeze must be used. Before starting up the cleaning unit, the pump has to be vented (see Service and Maintenance Instructions for Gas Turbine – Cleaning System – Mobile Cleaning Unit). The pump of the mobile cleaning unit must not on any account be run without water - not even for checking. Z For carrying out the following tasks, P&I diagram "Auxiliary air /

Cleaning" and/or "Draining" (if available) may have to be consulted. Approx. 50 l (13 gallons) of cleaning solution are required for one cleaning operation.

1. Remove the plugs from the header of the instrument air system. 2. Flexible hoses for compressor cleaning were included in the scope of supply. They have to be connected to the instrument air header and to the solenoid valves provided for activation of the blow-off valves (see

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P&I diagram “Auxiliary air / Cleaning“). Note: Since during standstill of the gas turbine GT compressor air is not available, the blow-off valves have to be kept closed by instrument air from an outside supply source to prevent a major portion of the cleaning solution escaping via the blow-off valves. 3. Open the instrument air supply. 4. For draining the GT compressor open ball cock V141.1 (see P&I diagram “Draining“ or “Auxiliary air / Cleaning“). 5. Connect the hose of the mobile cleaning unit to port Q1 of the ring line on the GT compressor inlet casing. 6. Verify that the drain valve of the mobile cleaning unit is closed and that the mobile cleaning unit is in safe condition. Clean the tank, if necessary. 7. Check further that the vent screw in the pump head and the drain plug in the lower pump section are screwed in. 8. Fill the cleaning unit mixing vessel with the required amount of water. Note: At an ambient temperature below +5°C (41°F) the amount of water to be filled in is less, since antifreeze has to be added (see Service and Maintenance Instructions for Gas Turbine - Cleaning System - Use of Antifreeze). 9. Add the cleaning additive. Note: Observe the mixing ratio specified by the supplier. 9.1.9

Performance of cleaning The cleaning procedure is described in the Operating Instructions.

9.1.10

Measures after cleaning 1. Remove the cleaning unit connections from the gas turbine. 2. If there is the risk of frost, the cleaning unit must be drained thoroughly by opening the drain valve in order to avoid damage to components. 3. Shut off instrument air supply. 4. Close ball cock V141.1 (see P&I diagram “Draining“ or “Auxiliary air / Cleaning“). 5. Remove the hoses installed on the instrumentation and blow-off system for the cleaning process and close the openings at the instrument air end with the corresponding plugs. Note: The lines of the blow-off system shall not be closed in order to ensure ventilation of the control chamber of the blow-off valves and as such proper functioning of the blow-off system. 6. Empty the drainage vessel. Disposal of the accumulated liquid must be carried out properly in compliance with the laws applicable at the site location.

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9.1.11

Examination of cleaning result The cleaning result can be checked using the following methods: ■ Visual inspection of the blades with a boroscope. ■ Analysis of fouled cleaning water for non-water-soluble substances and/or analysis of conductivity. If the result is not satisfactory, clean the gas generator compressor once again.

9.1.12

Repair General information relating to the replacement of components (e.g. pressure switches, pressure sensors, limit switches, thermometers, pressure gauges, valves, etc.) not included in the present system description will be found in Chapter "General service and maintenance information". Should any further information be required, please contact the MAN TURBO AG After Sales Service.  General notes on the exchange of component parts [J 1 | 5]

9.2

Cleaning nozzles

9.2.1

Design and function The ring line with 6 nozzles (4 for cleaning and 2 for preservation) installed on the intake elbow serves for offline cleaning. Although the preservation nozzles originally envisaged for wet preservation of the base engine are installed, they must not be used, since dry preservation is preferable to wet preservation.

Design and location of cleaning nozzles

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Service and Maintenance Instructions for Gas Turbine 1

Intake elbow

9.3

Mobile cleaning unit

9.3.1

Design and function

2

Cleaning nozzle

The following illustration shows the components of the mobile cleaning unit and their arrangement. For carrying out a cleaning process, the hose of the cleaning unit must be connected to port Q1. A corresponding socket is installed on the acoustic enclosure for power supply. A pressure reducing valve and a pressure gauge are provided for pressure adjustment to 5 – 6 bar.

Design of the mobile cleaning unit

1

Electric motor

5

Pump

2

Supply hose

6

Filling nozzle

3

Pressure reducing valve / pressure gauge

7

Containers

4

Terminal box with switch

8

Drain/shut-off valve

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10

Annex

10.1

Spare Parts Catalog

10.2

Curves

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Annex © MAN TURBO AG

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