Drilling Engineer to organise pre-section meeting at the rig site, with rig and office personnel to discuss section objectives and hazards.
Gauge of all stabilizers will be checked prior to making up the BHA. Prior to RIH, the Drilling contractor will provide an accurate BHA report including serial numbers and dimensions of all the components.
If a steerable motor is used, the bent and the tool face offset must be verified by the DD, MWD Engineers and the Drilling Supervisor. The tool face offset must correctly be entered into the MWD computer and a hard copy passed to the drilling supervisor.
If GeoPilot RST is to be used ensure stabiliser is run on top of tool below flex collar to mitigate vibration.
Liners size must be optimized for flow rates and pressures.
Confirm chemicals (e.g. torque trim for WBM or acid for releasing stuck pipe) are readily available.
The instructions describing the well shut-in procedures will be posted in the dog house, drilling supervisor and toolpusher’s offices.
The following information is available in the doghouse, drilling supervisor and toolpusher’s offices: FIT, LOT, MAASP, casing burst pressures, Well Control datasheet.
Confirm primary and contingency bits (including milled tooth and insert tri-cone) are available on location.
Confirm hydraulics and bit nozzle requirements with Operations Engineer and dress bit accordingly.
Ensure the following information is available in the doghouse: Jar settings, weights (in air and mud) of the BHA and maximum pull. Note that the pull to activate the jars will be higher once the BHA is in the kick-off and tangent section.
Washpipe seals should be changed.
Mud Loggers to ensure that all ditch magnets are cleaned and re-installed in the header box. Metal recovered should be reported daily, as ‘metal recovered (grams) per total revs and reported in the DDR.
Mud Loggers to check and calibrate all sensors (gas, pit volume, pump stroke, torque, WOB, rpm etc).
There is no requirement to function test the PBL sub on surface.
6" Section Drilling - Sequence of Operations
Surface test all drilling tools. Repeat test at 1500m to confirm all sensors operational. There is no requirement to further test the tools until drilling commences.
Independent cross check DP tally when picking up 3 ½” DP
Prepare and RIH BHA. Fill pipe every 500m, break circulation every 1000m.
Before drilling out the shoe track a pit drill, strip drill and choke manipulation drill will be performed.
Ensure that mud all round is conditioned to parameters as specified in the programme.
Drill section to TD. Take surveys with MWD tool after every stand.
Closely monitor real time downhole vibration levels:
Perform swab test after any mud weight change.
Use at least 1.5% torque trim with water base mud to minimise vibration of downhole tools.
If cuttings thin sections are required for biostratigraphy perform the following:
Alternatively: Pump high vis pill, keep drilling with 60 rpm for 2100 strokes. P/U off bottom, reduce flow rate and pump cuttings into vertical and resume drilling.
If activating circulating sub pump ball down at normal flow rate until reaching 80% of string capacity. Pump the last 20% very slowly 5-10spm. This should stop the ball from being forced through the seat.
At TD of the section:
Continue to POOH with 5” and 3 ½” DP.
POOH with BHA and clear rig floor.
Accurate trip sheet volumes (in litres) will be maintained at all times.
These will be cross checked by Rig Tool Pusher, DSV and Mud Logger.
Mud logging unit will track volumes during trip and inform driller immediately of any discrepancy.
If there are any discrepancies, the well must be shut in and if safe to do so, the BHA run or stripped back to bottom.
Lay out the drilling tools. If possible download LWD data offline.
Rig up and prepare and run pipe conveyed logs as per the logging programme (if required).
Ensure driller is aware of vibration types and effects and action to take
Modify drilling parameters accordingly
Drill to the agreed sampling depth.
Slow TDS RPM to 80, drop WOB down to 3 - 5 Klbs and drill 2m.
Pump 3m3 of barolift while drilling with above parameters.
Once the barolift pill reaches the bit, pick up off bottom and reduce the TDS RPM to 20 until the bottom sample is in the vertical part of the well.
Once the bottom sample reaches the vertical part of the well, continue drilling with normal parameters until the next sampling depth.
Circulate hole clean.
Increase mud density to equivalent value of ECD.
Flow check.
Perform swab test.
Pump out of hole to KOP (8-1/2” hole) or TOL (5-7/8” hole) at same flow rate used for drilling
Flow check well for 30 minutes.
Rig up Schlumberger Wireline (if required), and Run cement bond evaluation logs in 7” Liner and Scab liner.