Method Of Statment Of Re-tubing Process.pdf

NEGEMCO FOR ENGINEERING & CONTRACTING METHOD STATEMENT NEG-016-MS-BR

TITLE Method Statement for Boiler Retubing

Revision 00

Method Statement For Boiler Retubing

Name Prepared By

Signature

Eng. Mohamed Abdel Nasser

Reviewed & Dr. Eng Arabi Soudi Approved By

1

Date

Rev.

26.06.2016

00

26.06.2016

00

NEGEMCO FOR ENGINEERING & CONTRACTING METHOD STATEMENT NEG-016-MS-BR

TITLE Method Statement for Boiler Retubing

Revision 00

CONTENTS 1.0 General 2.0 Scope of project 3.0 Documentation provided by APC 4.0 Scope of Work 5.0 Description of the activities to be cared out on site 5.1 Supply & erection of external scaffoldings 5.2 Preparation of equipment for handling 5.3 Preparation of boiler to start re-tubing 5.4 Pulling & Expanding of water tubes 5.5 Reinstallation of insulation 5.6 Reinstallation of refractory 5.7 Replace the boiler inlet duct expansion joint 5.8 NDE Execution 5.9 Prepare & execution of the hydraulic test 5.10 Prepare assisting & restoration for chemical cleaning 5.11 Mechanical cleaning inside the boiler & flue gas side 5.12 Painting 6.0 Documentations and activities 6.1 Preliminary documentations 6.2 Documents during work execution 6.3 Final Documents 7.0 Activities, Erection tools / machineries & Equipment 8.0 List of Annexes 8.1 Drawings of boiler No. 1 8.2 Welding Procedures Specifications (WPS) 8.3 Extension of Non-Destructive testing (NDT)

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NEGEMCO FOR ENGINEERING & CONTRACTING METHOD STATEMENT NEG-016-MS-BR

TITLE Method Statement for Boiler Retubing

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1.0 GENERAL This specification describes the activities to be performed and the material estimated quantities which have to be considered to execute the project of: “Full re-tubing for boiler no. 1 at the hot leach plant” The quantities and activities shown in this specification are for 1 Boiler, The following definitions shall apply to the specification: 

Manufacturer: Aalborg Engineering



Boiler Model: Water tube type O



Total No. of tubes is 1082 plus 66 super-heater coils



Boiler Steam Capacity: 110 T/hr



Design Pressure: 73.5 barg



Test Pressure: 95.6 barg



Steam outlet design temperature: 487 C

All documents and drawings both furnished by the Contractor / Boiler Designer shall be treated as proprietary information and shall not be used for other than their original purpose without writ- ten permission by the Contractor. 2.0 SCOPE OF THE PROJECT The scope of work of this project is the full re-tubing for boiler no. 1 at the hot leach plant the project consists of these main general activities:  Remove Cladding & insulation  Remove old refractory 3

NEGEMCO FOR ENGINEERING & CONTRACTING METHOD STATEMENT NEG-016-MS-BR

       

TITLE Method Statement for Boiler Retubing

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Remove old tubes and install new tubes gradually Remove old super-heaters coils and install new coils Perform all related fabrication works related to the re-tubing process NDT Examination Hydraulic Test Site Preparation for performance test Chemical Cleaning assistant Removal and erection of insulation and refractory

3.0 DOCUMENTATION PROVIDED BY APC APC will provide all the components and equipment drawings necessary for erection where are indicated the site welds and bolted connection. A list of the components with overall dimensions and weights will be also supplied. The Vendor shall inspect the existing components (i.e. insulation, ladders, gratings, cable trays etc.) which have to be temporary dismantled to allow the erection of the new equipment and which have to be re- installed after the installation of the new components.

4.0 SCOPE OF WORK The following activities are to be intended as part of Contractor scope of work:  Mobilization next to the working area  Transport all new materials (tubes, insulation & refractory from APC stock to the working site.

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TITLE Method Statement for Boiler Retubing

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 Preparation of work site as per safety instruction of Damietta Power plant

and

APC standards, including tool

rooms, temporary store,

temporary offices, provisional shop, bathrooms, portable dining rooms, and all facilities needed by the people during the execution of the works.  All necessary dismantling activities to allow the erection of new parts;  Management o f

all

wastes (including the one produced during

dismantling / erection activities) in accordance with local environmental regulations. In case there will be a dedicated waste management area inside the plant, the Supplier shall agree with Damietta Power plant on the possibility to it;  Temporary removal of all parts, which may interfere with other plant modification activities, all dismantled parts shall be kept under custody of Supplier. In case the parts shall be modified to allow their installation back in the original location, this will be part of Vendor’s scope of supply; their conservation, according to the different characteristics of their materials, and after their reinstallation.  Prefabrication and installation of:  Temporary structure to support the Steam Drum  Temporary structure for lifting the new part and the dismantle parts both from internal and external side of the boiler.  Temporary lower guide with a little care to movement the tubes and Coils inside of boiler.

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NEGEMCO FOR ENGINEERING & CONTRACTING METHOD STATEMENT NEG-016-MS-BR

TITLE Method Statement for Boiler Retubing

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 Any necessary modification to secondary steel structures (i.e. gratings, platforms, hand- rails, etc.), if necessary  All civil works;  Erection of new equipment supplied by Alstom and anything which is described in this technical specification  Testing and NDE in the power plant, (including the Hydraulic Test)  Perform the chemical cleaning.  Support to commissioning and boiler start up. 5.0 DESCRIPTION OF THE ACTIVITIES TO BE CARRIED OUT ON SITE 5.1 Supply and Erection of Externals Scaffoldings Supply and erection of the external scaffolding to be used in the execution of the activities of dismantling and installation 5.2 Preparation of equipment for handling  Prepare a temporary structure for handling and lifting of the components.  Identify storage areas.  Identification and enclosure the storage areas for new materials and existing materials to be recovered in the vicinity of the erection areas. Quantities and dimensions of scaffolding shall be estimated by the Vendor taking as reference the available drawings and after having performed a detailed plant visit.

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NEGEMCO FOR ENGINEERING & CONTRACTING METHOD STATEMENT NEG-016-MS-BR

TITLE Method Statement for Boiler Retubing

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5.3 Preparation of boiler to start re-tubing process  Perform a site visit to verify the extent of the parts to be temporary removed and re-installed;  Dismantling the internal floor and remove of refractory  Execution of one opening in the casing on the lateral wall of the boiler  Internal Scaffolding Erection  Dismantling of external interferences (stair, tubes, etc.)  Dismantling the internal roof  Dismantling of Drum expansions join.  Installation of the external structure to support the drum and lifting devices.  Installation of internal beam and lifting devices to internal lifting.  Erection of Internal Scaffolding.  Dismantling inner liner for the entire height of the duct, on the area of the tubes out of the inside the boiler to connect with the Headers. 5.4 Pulling & expanding of water tube in boiler  Boiler tubes to be removed by grinder or by proper technique to avoid any Damages or defects in the drums and heads tubes dimension OD 51mmx4mm wall thickness, material st.35.8.III Number of finned tubes is 272, material Rst37-2  Super-heater coils to be removed by means of cutting to keep them in good condition to be kept as spare parts  Old tubes to be replaced gradually, preferably from center to outside, to keep the steam drum, water drum and headers fixed in place to avoid any deformation or misalignment.  Before installing tubes, tubes ends and holes must be cleaned from scratches Burr, foreign materials …etc. by smooth emery paper before 7

NEGEMCO FOR ENGINEERING & CONTRACTING METHOD STATEMENT NEG-016-MS-BR

TITLE Method Statement for Boiler Retubing

Revision 00

starting the Expanding, the surface roughness must not exceed 125 microns for the tube and 200 micron for the hole.  Measurements for tube holes ID shall be taken prior to tubes installation.  Tube fins shall be grinded beveled, cleaned, and prepared for welding.  Remove 5 tubes from each wall: membrane, convection, and furnace, and prepare this area for sample installation to ensure that the new tubes are compatible for the existing situation.  During removing old tubes, steam and water drums surface to be cleaned by stainless steel cup brush.  Tube arrangement shall be in line, tubes shall be in proper alignment with tube holes for proper expanding flaring.  The amount of expansion can be found by using following formula:

 Tubes are to be positioned and aligned inside steam and water drums for proper expanding.  All tubes shall be installed by rolling and flaring as per ASME standard.  Super heater coils are to be installed and welded according to the given drawings  ALL welding joints must be according to ASME B&PVC code section IX. And following types of electrodes, See Annex 2 For Welding Procedures Specifications (WPS) Metal Tub St358.8 III Super-Heater 10CrMo910 Fins R St 37-2

Filler AWS Standard E7018-A-1 or ER70S-6 ER90-S-G E7018-A-1 or ER70S-6

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Origin West European North American West European North American West European North American

NEGEMCO FOR ENGINEERING & CONTRACTING METHOD STATEMENT NEG-016-MS-BR

TITLE Method Statement for Boiler Retubing

Revision 00

5.5 Reinstallation of Insulation 

Insulation removal of all parts previously described;



The insulation materials will be provided by APC, the material is: “Fired high alumina bricks”

5.6 Reinstallation of Refractory  Refractory removal of all parts previously described  The refractory materials will be provided by APC.  Install the refractory according the client design the material is: “Fired high alumina bricks” 5.7 Replace of the Boiler Inlet Duct Expansion Joint  Construct temporary structure to support the duct.  Dismounting of the existing expansion joint  Make an inspection to the existing expansion joint flange, where was installed the expansion joint and replace it if required and approved by APC.  Install the new Expansion joint including its internal insulation, 5.8 NDE Execution Perform all necessary NDE as per approved Inspection Test Plan (ITP) – see Annex 3 detailing the extent of examinations and tests on site. 5.9 Prepare and Execution the Hydraulic Test and Restoration Including the manpower, temporary material and equipment by the contractor, but the treated water will be supplied by APC

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NEGEMCO FOR ENGINEERING & CONTRACTING METHOD STATEMENT NEG-016-MS-BR

TITLE Method Statement for Boiler Retubing

Revision 00

5.10 Prepare Assisting and Restoration for chemical cleaning Including the manpower and normal construction equipment as welding machine, crane, lifting devices, manuals tools, etc

5.11 Mechanical Cleaning inside the boiler, flue gas side To remove deposits at finned tubes outside and to remove all dirtiness on the bottom of the channel from damaged concrete and dropped rust from tubes with mechanical methods and air compressor.

5.12 Painting Scope of Contractor will include touch-up of existing structures that were temporary dismantled and reinstalled, and all surface damaged during the project. The Vendor will supply all the required paints according to the indication provided by the Boiler Designer at the contract stage.

6.0 DOCUMENTATION AND ACTIVITIES 6.1 Preliminary Documentation Before starting the site activities, the Supplier shall submit the following documentation:   

Detailed schedule of the works (including manpower and erection tool details); List of personnel with relevant documents which have to be submitted to Plant Owner to obtain the necessary work permits;

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NEGEMCO FOR ENGINEERING & CONTRACTING METHOD STATEMENT NEG-016-MS-BR

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TITLE Method Statement for Boiler Retubing

Revision 00

List of machineries and tools that will be used during erection with their technical documents; Quality document for welding and test (i.e NDE, WPS, PQR, etc…); Preparation of erection “Method of Statement”

6.2 Document during work execution 

Request for inspection (RFI)

6.3 Final Documentation Final quality dossier comprising all test results, welding documents, material certificates etc…

7.0 ACTIVITIES, ERECTION TOOLS / MACHINERIES, EQUIPMENT Below is reported a summary of the main activities/tools/materials under Supplier scope. This list is indicative and cannot be considered binding for the Vendor or limited to these sole items:            

Supervision of the works; Machineries and consumable materials; Lifting and transport equipment; Handling of all materials Shipment to workshop of any material to be maintained after dismantling; Site mobilization and connection to electricity and water tie-ins which will be provided by Plant Owner free of charge; Cleaning of working area before and after work completion; Supply of all safety requirement and personal protection equipment for workers; Execution of all NDEs, Heat Treatments (if applicable); Dismantling and installation of insulation and refractory; Supply of local electrical panels; Supply of compressed air; 11

NEGEMCO FOR ENGINEERING & CONTRACTING METHOD STATEMENT NEG-016-MS-BR

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TITLE Method Statement for Boiler Retubing

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Waste management; Erection of electrical and I&C materials Painting and touch-ups; Preparation of work permits; Preparation, as per plant safety requirements, of all systems which will be subject to modification as detailed in this technical specification

8.0 LIST OF ANNEXES

8.1 Annex 1: Drawings of Boiler No. 1 8.2 Annex 2: Welding Procedures Specifications (WPS) 8.3 Annex 3: Extension of Non-Destructive Examination and Tests on Site

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NEGEMCO FOR ENGINEERING & CONTRACTING METHOD STATEMENT NEG-016-MS-BR

TITLE Method Statement for Boiler Retubing

8.1 Annex 1: Drawings of Boiler No. 1

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TITLE Method Statement for Boiler Retubing

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8.2 ANNEX 2: Extension of Non-Destructive Examination and Tests on Site

WPS (1) General Welding Procedure Specification No.: 4/WPS/ Negem Revision No.: 01

Date: 08/ June / 2006

Supporting PQR No. (s): 4 / PQR / Negem

Date: 07/ June / 2006

Welding Process (es): SMAW

Type: Manual

Prepared & Approved By:

Date:

Joints: (QW - 402) Sketch(es) :

TYPICAL BUTT JOINT

"Refer To Production Drawing For

PREPARATION

Joint Design : Backing (Yes or No) : Retainers (Yes or No) : Non-metallic (Yes or No) :

The Specific Joint Details to Be Used"

All Groove Welds, Double-Welded Joints, and Fillets as per drawing Yes Backing Material (Type) : Weld Metal or P-No.1 material No Retainer Material: None No Other:

Base Metal: (QW-403) P-No.: 1 Group No.: Any

TO

P-No.: 1

Group No.: Any

OR Specification Type and Grade: Thickness Range: Groove: Pipe Dia. Range : Groove: Other:

--------------------5.0-50.0 mm Unlimited

TO

Specification Type and Grade: Fillet: All Fillet: All

Filler Metal: (QW-404) Deposited Weld Metal Thickness Range: 1. Deposited Weld Metal for SMAW Maximum (t): For one pass Welding Process .4 F-N° / Other .5 A-N° / Other .5 AWS N° (Class) .6 Ø of Filler Metal

Groove:

Max. 50 mm

Fillet:

< than 12mm SMAW 4 1 E7018, E7018-1 2.5, 3.2, 4.0, 5.0 mm

25

All

-----------------------

NEGEMCO FOR ENGINEERING & CONTRACTING METHOD STATEMENT NEG-016-MS-BR

.7 .9 .10 .12 .14 .22 .23 .24 .27 .29 .34 .35 .36

TITLE Method Statement for Boiler Retubing

6mm / Ø of filler Metal < 1/4” Electrode Flux (Class) Alloying Flux Specification (SFA) With or Without Filler Metal Consumable Insert Solid or Tubular Electrode Sup. Filler Metal Alloying Elements Flux Trade Name Flux (Type) Flux Wire Class Re-crushed Slag

Revision 00

No N/A N/A A5.1 N/A N/A N/A N/A N/A N/A N/A N/A N/A

Other POSITION (QW-405) Position (s) of Groove:

SMAW

PWHT (QW-407) N/A Temperature Range: N/A Time Range : N/A Method For PWHT: N/A

All

Position (s) of Fillet :

Heating Rate: N/A Cooling Rate: N/A

SMAW

All

Note: Refer to applicable standard/Code (ASME VIII or ASME B31.1) for confirmation.

Welding Progression:

UPHILL

Gas (QW-408) Shielding Gas Yes:

No:

Type N/A Gas Backing Type N/A

Composition, % N/A Yes: Composition, % N/A

Flow Rate N/A No: X Flow Rate N/A

Trailing Gas Type N/A Other:

Yes: Composition, % N/A

No: X Flow Rate N/A

PREHEAT(QW-406) Min Preheat Temp.: 10 °C ; 50 °C if B. Metal Thickness.>25 mm Interpass Temperature, Maximum: 250 C° Preheat Maintenance: min. 50 °C all time during welding Other: Electrical Data (QW-409) Spray Short-Circuit Other Mode of Metal Transfer N/A N/A See Table below For: Current, Polarity, amp Tungsten Electrode Type: N/A Dia.: N/A Technique (QW-410) .1 String or Weave .3 Ø mm Gas Cup Size .5 Method of Initial and Interpass Cleaning .6 Method of Back Gouging .7 Oscillation .8 Contact Tube to Work Distance .9 Multiple or Single Pass (per side)

SMAW String or Weave N/A Grinding or Brushing if Necessary Grinding or Air Arc Gouging to Sound Metal None N/A As Required

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X

NEGEMCO FOR ENGINEERING & CONTRACTING METHOD STATEMENT NEG-016-MS-BR

TITLE Method Statement for Boiler Retubing

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.10 Multiple or Single Electrodes Single .11 Vacume Chamber Welding N/A .26 Peening None Surfaces are to be cleaned on both sides of weld preparation to remove all foreign materials that may cause weld defects. Tack welds: Should be performed by qualified welders and equally spaced; if not removed, ground and inspected before applying above welds Tack Weld with: WPS N°: 4/WPS/Negem or 6/WPS/Negem with extra preheat temperature when required Filler Metals Weld Layer

1st Side 1 2 : 2nd Side 1 2 :

Current

Travel Speed Cm/min

Process

SMAW SMAW : SMAW SMAW :

AWS Class

Dia. mm

Type

Polarity

Amps

Volts

E7018,E7018-1 E7018,E7018-1 :

2.5,3.2,4.,5. 2.5,3.2,4.,5. :

DC DC :

EP EP :

100-280 100-280 :

20-25 20-25 :

12 –16 12 –16 :

2.5,3.2,4.,5. 2.5,3.2,4.,5. :

DC DC :

EP EP :

100-280 100-280 :

20-25 20-25 :

12 –16 12 –16 :

E7018,E7018-1 E7018,E7018-1 :

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TITLE Method Statement for Boiler Retubing

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WPS (2) General Welding Procedure Specification No.: 12/WPS/ NEG Revision No.: 01

Date: 20 /April / 2007

Supporting PQR No. (s): 12/PQR/NEG, 4/PQR/NEG

Date: 15 /April/ 2007, 7/June/2006

Welding Process (es): GTAW+SMAW

Type: Manual

Prepared & Approved by : AMMAR AZAR

Date: 21 / April / 2007

Joints: (QW - 402)

"Refer To Production Drawing For The Specific Joint Details to Be Used"

Joint Design : Backing (Yes or No) : Retainers (Yes or No) : Non-metallic (Yes or No) : Base Metal: (QW-403) P-No.: 1

PREPARATION for

TYPICAL BUTT JOINT

Sketch(es) :

All Groove Welds Single-Welded Joints, and Fillets As per Drawing Yes for SMAW Backing Material (Type) : GTAW weld metal No Retainer Material: None No Other: Group No.: Any

TO

P-No.: 1

Group No.: Any

OR Specification Type and Grade: --------------------TO Specification Type and Grade: ----------------------Thickness Range: Groove: 1.5 - 20 mm Fillet: All Pipe Dia. Range : Groove: Unlimited Fillet: All Other: Filler Metal: (QW-404) Deposited Weld Metal Thickness Range: 1. Deposited Weld GTAW Groove: Max. 14 mm Fillet: All Metal 2. Deposited Weld SMAW Groove: Max. 50 mm Fillet: All Metal Maximum (t): For one pass < than 12mm Welding Process 1. GTAW 2. SMAW .3 Size of Filler Metal 2.0, 2.4 mm N/A .4 F-N° / Other 6 4 .5 A-N° / Other 1 1 .6 Diameter of Filler Metal Electrode N/A 2.5, 3.2, 4.0, 5.0 mm .7 6mm / Ø of filler Metal < 1/4” N/A No .9 Electrode Flux (Class) N/A N/A .10 Alloying Flux N/A N/A .12 AWS N° (Class) ER70S-6 E7018, E7018-1

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NEGEMCO FOR ENGINEERING & CONTRACTING METHOD STATEMENT NEG-016-MS-BR

.12 Specification (SFA) .14 With or Without Filler Metal .22 Consumable Insert .23 Solid or Tubular Electrode .24 Sup. Filler Metal .27 Alloying Elements .30 Deposited Weld Metal Thickness .33 Classification .35 Flux Wire Class .36 Re-crushed Slag .50 Flux Added to face of weld joint Other POSITION (QW-405) Position (s) of Groove:

TITLE Method Statement for Boiler Retubing

A5.18 With filler metal None Bare (solid) or metal cored N/A N/A Max. 14 mm ER70S-6 N/A N/A None

GTAW

All

SMAW

All

All

SMAW

All

00

A5.1 N/A N/A N/A N/A N/A Max. 50 mm E7018, E7018-1 N/A N/A N/A PWHT (QW-407) N/A Temperature Range: N/A Time Range: N/A Method for PWHT: N/A

Position (s) of Fillet : GTAW

Revision

Heating Rate: N/A Cooling Rate: N/A Note: Refer to applicable standard/Code (ASME VIII or ASME B31.1) for confirmation. Gas (QW-408)

Welding Progression: GTAW: UPHILL SMAW: UPHILL PREHEAT(QW-406) Shielding Gas Yes: X No: Min Temp.: 10°C; ( GTAW:50 °C , SMAW: 50 °C if T>25 mm) Type Composition, % Flow Rate Inter-pass Temperature, Maximum: 250C° Ar 10-16 l/m Preheat Maintenance: None Gas Backing Yes: X No: Other: Type Composition, % Flow Rate Electrical Data (QW-409) Ar Welding Grade 4-10 l/m Spray Short-Circuit Other Trailing Gas Yes: No: X Mode of Metal Transfer N/A N/A Type Composition, % Flow Rate See Table below For: Current, Polarity, amp N/A N/A N/A Tungsten Electrode Type: EWTh-2 (Red) Dia.: 2.4 / 3.2mm (Electrode Angle:90o, Tip Dia:1.1-1.5mm) Technique (QW-410) GTAW SMAW .1 String or Weave String or Weave .3 Ø mm Gas Cup Size #4 to #12 N/A .5 Method of Initial and Interpass Cleaning Grinding or Brushing if Necessary .6 Method of Back Gouging N/A .7 Oscillation None .8 Contact Tube to Work Distance 6mm from Electrode Tip N/A .9 Multiple or Single Pass (per side) As Required .10 Multiple or Single Electrodes Single .11 Vacume Chamber Welding N/A .26 Peening None

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Notes: -Surfaces are to be cleaned on both sides of weld preparation a minimum of 15mm to remove all foreign materials that may cause weld defects. -Completed or partially welded joints shall be cleaned (brushing or polishing wheel) on the exterior, and when accessible, the interior. Final weld shall be checked by the welder. -Arc strike out side weld joint shall be avoided. -Arc starting (GTAW) shall be by superimposed high frequency or by high voltage pulse, the touch method is not recommended. Tack Weld with: WPS N°: 4/WPS/Negem or 12/WPS/Negem Process

Filler Metals AWS Class Dia. mm

1 Side Root Hot Pass Balance or

GTAW GTAW GTAW

ER70S-6 ER70S-6 ER70S-6

1.6,2.0, 2.4 1.62.0, 2.4 2.0, 2.4

DC DC DC

EN EN EN

Balance

SMAW

E7018,E7018-1

2.5,3.2, 4.,5.

DC

EP

Weld Layer

Type

Current Polarity Amps

Volts

Travel Speed cm/min

75-150 90-280 120-280

8-12 8-12 8-12

5-10 5-20 5-20

100-280

20-25

12 –16

st

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TITLE Method Statement for Boiler Retubing

8.3 ANNEX 3: Extension of Non-Destructive Examination and Tests on Site Extent of Non Destructive Examinations (NDEs) on Site 1. Pressure Parts Visual Test of tubes bevel:

VT 100 %

Visual test of welds:

VT 100 %

Radiographic test of butt welds:

RT 100 %

Magnetic or dye penetrant test of butt welds:

MT 100 %

Magnetic or dye penetrant test of welds to pressure parts:

M T 100%

2. Ducts and Secondary Structures Visual test of welds:

VT 100 %

Magnetic or dye penetrant test of plates, beams butt welds:

MT 100 %

Magnetic or dye penetrant test of plates, beams fillet welds:

MT 20%

3. Applicable Codes and Standards NDE procedures and acceptance criteria will be according to: Pressure Parts: Ducts and Secondary Structures:

ASME Code / EN Code Structural Welding Code AWS D1.1

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