Negative Operational LL with Faroe

Brasse (31/7-3 A) – Reservoir section

What happened:

It took 5 hours to drill the wiper plugs in the Weatherford liner. This is twice as long as normal. Used 3 times the force to drill the plugs, than was recommended in the Section Recommendation, and in the Smith PDC bit procedure for drilling plugs.

What was planned:

Drill out wiper plugs

What was learned:

3 possible reasons; 1. The Smith Axeblade PDC bit has dull PDC cutters, not sharp at all. 2. The wiper plugs were of another type than what was normally drilled out (Weatherford instead of Halliburton, liner instead of casing float equipment). 3. There was not cement behind the top wiper plug, like there normally is with casing jobs, where the wiper plugs are set on seabed. First 2-3 m3 of displacement is done with the cmt pump, leaving the liner volume of cement behind the plug.

What actions are required:

Always leave some cement behindwiper plug, consider using different float equipment, or use a rock bit to drill out shoe track if short distance from shoe to core point.