Swabbing Equipments Mod 2

Technical Report SWABBING EQUIPMENTS & OPERATION Well completion by swabbing In some oil wells, the bottom hole pressure may be insufficient to lift fluid continuously. Because a surface flow rate cannot be maintained and measured, routine flow and buildup tests cannot be used to evaluate reservoir properties and determine well productivity. In these instances, a swabbing tool can be run at regular intervals to keep fluid flowing from the formation more or less continuously. By carefully recording the volume of fluid recovered from each swabbing run as a function of time, one can determine the rate of fluid feed-in from the formation to the wellbore. These data can then be used to estimate well productivity or formation permeability using the methods outlined in the discussion of single-point tests. The information gained from a swabbing test can also be particularly useful in determining whether a pumping unit should be installed on a well and in determining the proper pump design. Swabbing is applied: 1. To remove drilling mud from a borehole. 2. To remove disintegration products evolved from the acidizing treatment. 3. After implementing hydro-fracturing of formation. 4. Before performing perforation & shooting jobs (to reduce the fluid level prior to perforation). 5. After perforation & shooting jobs to improve the inflow. 6. To locate a dynamic level of fluid in a well - to determine the pump setting depth. 7. When changing a borehole fluid. 8. To start up the lift by creating a pressure drop. 9. To identify the inflow of a fluid. 10. To discharge a gas well and withdraw a fluid, which can reduce or fully stop gas production. Surface Equipment: 

Stuffing box is designed for removing oil and water off a cable/wireline by squeezing and for preventing the hoist facilities and well site from oil/water sprinkling and contamination.

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Lubricator is a chamber for accommodating the downhole equipment. Its’ length and dimensions depend on the type of equipment applied in swabbing the borehole lift. Available are cups of diameter 3-1/2", 27/8", and 2-3/8" as well as cups of a smaller size (if needed).

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Discharge tee. It has a straight vertical hole of 3mm diameter and a horizontal outlet of 2mm diameter. The horizontal outlet of the tee has a 900 -revolving ball cock on one side and a high-pressure ball with a pressure gauge on its opposite side.

Downhole equipment: 

Cable head (wireline socket). It is designed for making up a cable / wireline to a logging tool.

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Swivel. A rotating swivel prevents a cable / wireline from twisting in downhole operation.

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Weighting rod. Weighting is necessary to put a swabbing assembly downhole.

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Swab mandrel. Swab cup mandrel.

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swab cup. It is a basic cup designed for operation with the medium and high fluid loads. Allows withdraw a large volume of fluid. Sandline Flags

Oil Saver

Sinker Bar

Oil Saver Parts

Oil Saver Rubbers

Swab Cups

Rope Socket

Swabbing Procedures Which job does the swabbing begin? 1. Usually after pump equipments will be removed from the well for inspection and servicing and replacement. 2. Then adding or reperforate a pay zone interval using Tubing Conveyed Perforation penetration and swab test commingle to identify the fluid content and the PI.

Preparation: 1.

The ID of swabbing string should be of same specification. 2.

The drift check with standard drift gauge for tubing should be conducted before RIH swabbing string.

The total length of stuffing box and lubricators should be at least 2 meters more than the length from rope socket to swab cup, which should

be safe and reliable to prevent blowout. What are the tools supplied by Client?

Swab Cups Western Silverline (Guiberson) NUF Style -Heavy Load Cup

Oil saver rubbers Western Silverline (Guiberson) Operation Procedures: 1.

Link braided line, rope socket and sinker bar, and connect lubricators. 2.

Connect swab mandrel without swabbing cup to sinker bar to check the ID of tubing and 6 marks shall be made on the swab line (3 marks when the in lubricator, 2 marks after 50m and one marks after 100m from first marks) using two pipe wrenches. Initialize depth meter then install it on sand level.

The upper one flag mean the sinker bar touch the master valve. Three flags mean the sinker bar in lubricator. Two flags mean the sinker bar will be in lubricator after 50m. The lower flag mean the sinker bar will be in

3.

Link swab cup after POOH sink bar, then put into swabbing head. Continue RIH swab after connecting lubricators with the speed no more than 150m per min. The submergence should be controlled within

200m. If there is no digital depth meter, the driller should manual or mechanical depth meter when swab tools (sinker bar) go down. The driller must control the speed of the sinker bar when the bar comes back to lubricator in the rig floor because if he did not control & observe the stars in swab line the sinker bar will strike master valve & in this case the rope socket will broke and the sinker bar will fall in the well and this large problem in the petroleum company. 4.

It should not be run too deep when unclear of liquid depth and be tried gradually to deepen.

5.

Check the lubricators once every 5 times swabbing and make sure the packing of lubricators in good

condition. The driller should check the saver rubbers lubricator once every 5 trips (Runs) swabbing & confirm that the saver rubbers and/or swab cup is good or needs replaced. Remark it at swab report 6.

If blowout is observed while swabbing then POOH until swab enters into lubricators and then close swab valve. The pressure difference should not be too large when swabbing for sand produced formation and the uplifting speed should be reduced. Bleed tubing and or casing pressure (by opening casing valve to flow line or manifold valve The speed of sinker bar when the driller goes down in the well before tagged should be 140 m/min, when sinker bar go down after level fluid should be 75m/min. If the natural flow is observed while swabbing however, POOH swab tools until swab enter the lubricator and after that open the master valve and flow T. Natural flow should be recorded and report to company man.

Tim e

Dischar ge level (cm)

Current tank level (cm)

Volume of fluid This Run =[Discharge-current level] x 0.05 (cubic m)

Tubin g press ure psi

Remarks

In the Return tank it should record the cumulative volume of the oil, Water cut each Run by manual centrifuge, swab depth, fluid level, No of the Run and casing pressure each Run. Calculation of the volume of the oil: Return Tank capacity = 8 m3. 1 cm = 0.05 m3. Volume liquid in the tank = level of fluid m3 * 0.05 m3. By time and increase of fluid volume it should drain apart of fluid volume to next tank record the new volume and remark it at swab report

What are the outcomes needed from this job? According to swab Report: If the water cut more than 98% this zone in this well is not productive zone. If the water cut 85 % the GNPOC have decision to M/U ESP or PCP in this well.

What the next job will be after termination of swab? If found pay zone intervals low influx, proceed with TCP and swab comingle with another pay zone .Pull and lay down the tubing, packer and perforating gun assembly out of the well.

Current well program 1-Install a full-opening TIW stabbing valve and swab equipment.

2-Swab the well to evaluate the fluid content and PI of the pay zone intervals. Swab a minimum ±40.0 m3 of fluid from the well or until the measured water cut has stabilized, whichever comes first. Record all relevant swab information (volume recovered per swab, swab depth, fluid level, fluid type, water cut). Make sure KCL kit is onsite (to differentiate cushion water from formation water). Collect samples and report if any sand is being recovered. Don’t POOH with packer in case of sinker bar getting lost inside the hole, Run-in with another sinker bar and continue swab. The swab test result is to be sent for evaluation. Rig out the swabbing equipment. Pull and lay down the tubing, packer and perforating gun assembly out of the well. Note in the daily report if all the charges have fired a) Based on swab test result pay zone interval(s), If found they have a good oil and influx, proceed with Pump (ESP or PCP) Installation Program: b) If found pay zone intervals low influx, proceed with TCP and swab comingle with pay zone interval .Pull and lay down the tubing, packer and perforating gun assembly out of the well. Note in the daily report if all the charges have fired In the Return tank it should record the cumulative volume of the oil, Water cut each Run by manual centrifuge, swab depth, fluid level, No of the Run and casing pressure each Run. Calculation of the volume of the oil: Return Tank capacity = 8 m3. 1 cm = 0.05 m3. Volume liquid in the tank = level of fluid m3 * 0.05 m3. By time and increase of fluid volume it should drain apart of fluid volume to next tank record the new volume and remark it at swab report