Casing and Liner Running Procedures

1. General Running Procedure

1. Visually check each joint of casing/liner to ensure all joints are clear of foreign matter, measured and drifted.

Note: To prevent foreign matter entering the string whilst running it is necessary to:

• use a casing/liner cover where appropriate
• ensure dope is only applied to the pin end joint prior to make up.

2. Reduce the annular preventer closing pressure to less than the collapse rating of the casing/liner, if necessary.

3. Make up a full opening safety valve (in the open position) on the casing circulating swage and position it in a readily accessible drill floor location.

4. Make up the shoe floats and shoe track as per the running list.

Note: When thread-locking, ensure that both pin and box are clean and dry. The thread lock compound shall only be placed on the pin of the connection with the joint pulled to one side so that nothing can fall into the casing/liner.

5. Check float equipment after the shoetrack is run in to ensure the float is holding and that circulation is possible.

6. Install centralisers as per the centraliser programme.

7. Partially fill each joint and completely fill every five joints.

8. Make up the connections in accordance with API Spec 5CT.

9. Run the casing/liner smoothly, avoiding high acceleration and deceleration which could cause unnecessary surge/swab pressures.

10. Limit the casing/liner lowering speed to 45 sec/joint or to the optimum speed from surge/swab calculations.

11. Monitor returns constantly by using the trip tank and inform the Driller of any potential loss circulation zones.

Note 1: Returns shall be made to the same tank as is used for filling.

Note 2: When using side door elevators, avoid impact loading which can open the elevator. When the hook load approaches the safe working load or when the shoe enters open hole, slip type  elevators shall be used.

12. Monitor drags.

Drags usually increase as more casing/liner is run in to the open hole (particularly in deviated hole sections), a normal upwards trend should be observable. If a departure from this trend is observed and drags begin to become excessive, the following actions are suggested:

• Chechk formation logs and survey records to determine if drags are associated with a particular geological or directional event.
• Check the calliper log (if available) for evidence of under/over gauge hole.
• Investigate possibility of a mechanical obstruction down hole (BOP’s, previous shoe, junk etc., based on the geometry of the string).
• Reciprocate the string to determine if the drags reduce.
• Attempt to rotate string if running a rotating liner hanger.
• Break circulation slowly, monitoring the pump pressure and returns for signs of packing off.
• Circulate bottoms up and monitor the shakers (if possible).
• Attempt to wash down monitoring the drags closely.

Note:   If drags remain excessive and continues to increase, consideration should be given to pulling the casing/liner for a wiper trip.  This will depend on the shoe depth and the desired TD.

13. Count the joints of casing/liner remaining on deck before landing the casing/liner at the settling depth and compare this number against the amount in the hole and amount received at the well site. This should confirm that the casing/liner is set at the proper depth.

14. Minimize the time between landing the casing/liner and breaking circulation to avoid plugging the float equipment.

Note: the last casing joint or landing string stand should be circulated down.

15. Land the casing such that it is at a safe height for installing the cementing head, i.e., 4 feet - 5 feet above the rig floor if possible.

16. Circulate a minimum volume of 150% of the annulus/casing/liner contents, once circulation has been established.

Note: condition the mud while circulating, to ensure that the mud weight is uniform through the circulating system and that gas levels are at a minimum. YP and gel strengths should be at the desired values.

For deviated wells, circulate 1 ½  times annulus/casing contents

Additional Notes

• API modified compound (if available) shall be used when making up casing. When API modified compound is not available, the proper friction index for the compound substituted shall be used.
• No welding shall be carried out on heat treated tubulars (ie., N-80 grade and above).
• Float collars and shoes should be made up similarly, thread-locking in the rotary table is to be avoided if possible, and whenever possible should be carried out beforehand.
• Short joints in the casing string shall be placed near the pay zone(s) to facilitate depth verification with a casing connection locator (CCL).
• When the casing is about to be landed, the Drilling Supervisor and Contractor Toolpusher shall count the joints of casing remaining on deck and compare this number against the amount in the hole and amount received at the rig site. This will confirm that the casing will be set at the proper depth. This also applies when a DV collar or any other special joint or piece of equipment is made up to ensure proper space out of the DV collar which is particularly important for simultaneous slurry displacement during two stage cement jobs.
• Avoid reciprocating casing while circulating just prior to landing off with hanger in the BOP area or through the bell nipple. Either run to depth and circulate, pull back and install hanger or keep the hanger out of the areas mentioned above.

2. Specific Requirements

20in Conductor

The following requirements and precautions shall be followed:

• Casing shall be run with Drilling Contractor’s equipment and personnel.
• Casing services shall only be used when required equipment is not available in the drilling unit contract.
• Shoe of 20in casing should be set as such a depth that it cannot interfere with a collar of the 13.3/8in casing when this is picked up out of the slips while running.
• Special lengths of landing joints shall be requested by the Drilling Supervisor. Each rig has a different rig floor elevation and for the different options of landing depths for the conductor different landing joints will be required.
• Casing service company shall be on standby on site, and shall only be utilised if significant down time will occur due to failure of contractors equipment.

Offshore

1. Coordinate with field dive vessel to cut four windows in the 30in conductor at the seabed with 90⁰ phasing. Size of windows to be 6in wide x 12in high.

2. Run 20in conductor as follows:

• Float shoe-stab in type
• 20in conductor to seabed

3. Run stab-in tool (with 2 centralisers) on 5in drill pipe and stab into shoe. Fill up annulus with seawater to check seal integrity.

4. Circulate casing annulus clean with 50 bbls viscous gel spacer followed by two annular volumes of seawater.

5. Cement with Class ‘G’ cement with 1.5 % CaCI₂ using 200 % excess (1500 sxs). Divers should observe cement returns at seabed.

6. Observe for back flow:

Onshore

1. Run 20in conductor as follows:

Float shoe stab-in type

20in conductor to surface

2. Run stab-in tool (with 2 centralisers) on 5in drill pipe and stab into shoe. Fill up annulus with water to check seal integrity.

3. Circulate casing annulus clean with 50 bbls viscous gel spacer followed by two annular volumes of water.

4. Cement with Class ‘G’ cement with 1.5 % CaCI₂ using 200 % excess (1500 sxs). Observe cement returns at sea bed.

5. Observe for back flow:

6. Displace drill pipe with sea water (1 bbl under balance)

13.3/8in Intermediate Casing

Run 13 3/8in intermediate casing as follows:

1. Float shoe made up with Baker Lock on one joint.

2. FLloat collar joint with first stage shut off baffle in box end (this will give a +/- 80 ft shoe track).

3. Casing up to +/- 50 ftinside the 20in casing.

4. External Casing Packer (ensure that ECP is above 20" float collar).

5. Stage Collar

6. Casing spaced out as required to wellhead

7. Running tool and landing string.

Notes :

• Slip and seal assembly type 13 3/8" casing hanger will be used to hang casing.
• Do not place any centralizers over casing couplings.
• The External Casing Packer (ECP) will be run and located in the string 40' to 60' above the 20" casing shoe. This packer will be utilised to ensure a successful second stage cement job due to loss circulation characteristics of this hole section and provide a barrier from corrosive water aquifers.
• Check that ECP shear pins are set as per manufacturer recommendations.
• Do not load flexible wiper plug into cement head until ready to cement.

9.5/8in Production Casing

Run 9 5/8in production casing as follows:

1. Float shoe made up with Baker Lock on one joint.

2. One joint with two centralizers per joint (80 ft shoe track).

3. Float collar joint with first stage shut off baffle in box end.

4. Casing up to +/- 50 ft inside the 13.3/8in casing.

5. Casing spaced out as required to wellhead.

6. Running tool and landing string.

Notes:

• MSIPC is to be located +/- 50 ft inside 13 3/8" casing shoe.
• Handle MSIPC with care to avoid damage. Check for physical damage.
• While making up MSIPC care must be taken so that no slips or tongs are applied to the rubber inflation element or valve collar.

7in Liner

Run 7in liner as follows:

1. Float shoe made up with Baker Lock on one joint.

2. One joint casing (to give +/- 80 ft shoe track).

3. Landing Collar made up on 20' pup joint.

4. Casing up to top of Arab ‘D’.

5. 4 ft ECP, 20 ft pup joint, ES Cementer and 5 ft handling pup joint (Already made up).

6. Casing up to 300 ft inside 9 5/8in casing.

7. 7in Hanger with 6 ft tie back receptacle made up on RP setting tool.

8. 5in drillpipe to surface.

Notes:

• Rotating system to be assembled and tested with RP setting tool pinned for 60,000 lbs shear release', with Howco 2 - plug system (SR plug set) attached to the system
• Space out to have Liner Hanger away from 9-5/8" casing collar.
• Baker-Lock shoe, Landing Collar, full joint and ECP.
• Reciprocation or rotation may be required to get liner and ECP to planned setting depth.
• The rotating liner hanger is capable of rotating with up to 60,000 lbs weight. Rotate with a maximum weight on liner of 20,000 lbs, and only if required.
• Check External Casing Packers for operating pressures.
• ES cementer opening pressure set to +/- 2 750 psi. Closing pressure +/- 1275 psi over final circulating pressure. ECP setting pressure + 2,000 psi and Hydraulic hanger setting pressure + 1,500 psi.

Backup equipment comprising the following is required on site in case of a leaking liner lap:

• a liner tie back mill and PBR mill
• a tieback packer with PBR extension.

4.1/2in Liner,

Run 4.1/2in liner as follows:

1. Float shoe made up with Baker lock on one  joint.

2. Ball catcher sub and one joint casing.

3. 4 ft ECP made up with Baker lock on 20 ft, pup joint.

4. DV tool.

5. Casing up to +/- 300 ft inside 7in casing.

6. Liner Hanger with S6 packer and 6 ft tie back receptacle made up on LN setting tool.

7. 3.1/2in and 5in drillpipe to surface (fill drillpipe every 15 joints).

Notes:

• Non-rotating system to be assembled and tested with LN setting tool and Halliburton ‘SR' Plug Set, attached to the stinger.
• Space out to have liner hanger away from 7" casing collar.
• Baker-Lok shoe, landing collar, full joint and ECP.
• Reciprocation without rotation may be required to get liner and ECP to planned setting depth.
• ECP inflation pressure set to +/- 1 800 psi. Closing pressure +/- 800 psi.
• ES cementer opening pressure set to +/- 2 750 psi. Closing pressure +/- 1 100 psi over final circulating pressure.
• Turbulators to be spaced evenly over liner length.
• Liner to be filled every five joint while running in.
• Liner running speed should not exceed 45 seconds per joint.
• Liner hanger setting pressure to be set to +/- 1 200 psi.