1. Preparation
The Drilling Supervisor shall approve and provide written instructions to the Contractor Toolpusher prior to any trip out of the hole. These instructions shall include the:
- sequence of operations i.e. flow check, circulate bottoms up, drop survey, etc.
- maximum allowed overpull
- procedures if tight hole is encountered
- maximum running/pulling speeds
- preparation of equipment for the following operation when out of the hole
- Trip sheet
Pipe Tally
The drilling contractor shall ensure that a master drill pipe tally book is maintained at all times. This shall include stand number, single number, single identification, drill pipe grade, single length, stand length and total length.
Trip Tank
Prior to pulling out of the hole, the trip tank shall be filled. The fill-up pump to the trip tank should never be left running while tripping out.
Circulation
- For any trip out of the hole, a minimum of one bottoms up circulation, or appropriate circulation for deviated wells, shall be performed.
- When circulating to condition mud, a circulating rate of 50 - 75% of the normal circulating rate shall be used.
- A trip sheet shall be filled out by the Driller and Mud logging contractor for each trip out of the hole.
2 - General Guidelines
Responsibilities
The Drilling Supervisor shall be on the rig floor for the first 10 stands during tripping out to observe for correct hole fill, overpull, etc. He shall also be on the rig floor for the last five stands when tripping in, tight hole problems, testing mud motors & MWD, RIH across liner hanger and when casing 3 stands off bottom.
Pipe Movements
- Care shall be exercised to minimise surge/swab pressures by controlling the speed of pipe movements.
- Pull the pipe carefully and check for swabbing. In the event of the hole swabbing, the pipe shall be run back to bottom and the hole circulated bottoms up. Mudloggers shall run the swab programme prior to each round trip to determine the maximum trip speed.
Notes: A hole is swabbing whenever the volume of fluid required to fill the hole is less than the volume of steel pulled out of the hole. THE HOLE CAN BE SWABBING WITHOUT FLOW AT THE FLOWLINE.
Circulation, Hole Fill, and Pipe Fill
- During tripping operations, the hole shall be kept full at all times.
- The pipe shall be filled every 10 stands while running in the hole and the displacement checked.
- When pulling the pipe, the hole shall be kept full from the trip tank. The hole shall be checked regularly to ensure that it is taking the correct amount of fluid.
- The volume required to fill the hole every 3-5 stands shall be recorded in the Trip Sheet until the bit is out of the hole.
Tight Hole / Bridging Conditions
- If tight hole or bridging conditions occur during trips, the pipe shall be pulled back to the nearest stand and reaming/washing commenced in accordance with stuck pipe procedure.
- If tight spots occur while tripping out, the top drive or kelly shall be engaged to commence reaming and circulating out.
- Reaming trips might be required prior to running LWD/density tools and/or 7in liner.
Directional Wells
While tripping out of the hole from below the surface casing in directional wells:
- reciprocate at all times and rotate the pipe at intervals while circulating and conditioning the mud prior to POOH
- record the pick-up, slack-off and rotating weight indicator readings with the mud pump off. Note: These values shall be used to monitor changes in drag during pulling out.
- the top drive, if available, shall be used to pump out and/or ream out the first 5 to 10 stands off bottom.
Flow Checks
While tripping flow checks shall be taken:
- just off bottom
- at the cement casing shoe
- prior to pulling drill collars through BOP stack
- after BHA out of horizontal section
- while RIH after drilling out shoe
- while RIH before BHA enters horizontal section.
3 - Requirements When Out Of Hole
Time Out of the Hole
The time spent with the pipe out of the hole shall be minimised wherever possible. Operations such as routine repairs and slipping and cutting of the drill-line shall be performed with pipe at the casing shoe whenever possible.
Requirements When Out of Hole
The trip tank volume indicator shall be set at 1/2 barrel gain or loss whenever the trip tank is being circulated on the hole.
Whenever the blind rams are closed, the Driller and the Assistant Driller shall open the rams and check the fluid level at least every half hour, fill the hole as required and report any losses to the Drilling Supervisor. (Before opening blind ram open choke)
During logging operations, the trip tank shall be circulated continuously to keep the hole full. The volumes shall be recorded every 15 minutes and any losses reported to the Drilling Supervisor.
Whenever the mud pumps are turned off with the pipe still in hole, the trip tank shall be circulated continuously. The volume shall be recorded every 15 minutes and any losses reported to the Drilling Supervisor.
4 - Wiper Trips and Check Trips
Wiper Trips
Wiper trips shall be run at the discretion of the Drilling Supervisor and Drilling Contractor Toolpusher:
- during logging when hole conditions deteriorate and become sticky
- after logging and before running casing when hole conditions deteriorate and become sticky
- before RFT tools are run
- to push junk down the hole (e.g. lost SWS bullets, etc.).
- after 500-1000 ft of hole has been drilled
Note: In general, wiper trips shall be made to the shoe. However, when there are no indications of hole problem but there is a major change in parameters, a short trip of 10-15 stands shall be made.
Check Trips
Check trips shall be run at the discretion of the Drilling Supervisor and Drilling Contractor Toolpusher but shall be run:
- whenever significant torque/drag increase is noted
- before running casing if hole conditions during logging indicate that this is necessary
- during logging when mud overbalance is limited/low or there is gas cutting of mud
- when the bit has been on bottom for 24 hours.
For casing check trips, the BHA shall include full gauge stabilisers and be at least equal in stiffness to the casing string. MWD’s, NMDC’s and other expensive BHA components shall not be run.
The following table contains the basic guideline procedure to be followed when making a check trip:
1. Circulate bottoms up
2. Flow check for 15 minutes
3. Slowly pull 10-15 stands while using the trip tank to ensure that the hole is taking the correct quantity of mud
4. Flow check
5. Run back to bottom, check for fill and for flow again
6. Circulate bottoms up and condition the mud
7. Check mud returns for gas and salinity and report to the Drilling Supervisor
Note : If a well demonstrates a tendency to swab, pumping out of the hole maybe necessary.
5 - Making Connections
The following guideline procedure shall be followed for all drilling operations in order to minimise the time during which the drill string is motionless:
1. Drill the stand/joint down to the desired point but DO NOT drill-off the WOB or stop the pumps
2. Reduce the rotary speed to 20-30 RPM
3. Begin upward movement of the pipe while maintaining 20-30 RPM rotation
4. Pull one stand/joint of pipe above the rotary to wipe all newly drilled hole
5. Lower the pipe and REAM the stand/joint down, if necessary
Note : The Directional Driller shall be notified before any reaming is carried out
6. Repeat Steps 4-5 until drag and torque are acceptable
7. Lower the drill string without rotation and observe drag
8. Set the slips and break the tool joint to make connection
9. Pick-up the new stand/joint of pipe and make the connection
10. Start the pumps, lift the pipe and remove the slips
11. When the mud pumps are near required speed, begin rotation, lower the pipe and resume drilling
12. When the pipe is in the open hole, always set the slips on a down stroke long enough to ensure that the pipe is actually moving down the hole when the slips are set; never set the slips with drill pipe tension on the BHA.