Negative Operational LL with Wellesley

Grosbeak West (35/11-21 S) – Reservoir section

What happened:

During RIH of the DST string the sample carrier was over-torque to 14000 ftp instead of 4000 ftp. This is the only DST tool which needs special treatment as it can not be made up in town. The carrier contains 8 single phase sample bottles and these need to be installed offshore. The carrier was picked up to the rig floor and made up to the string. The saver sub below is a 3 1/2″ PH6 connection and was correctly made up to 7200 ftp. The next was the end connection of the sample carrier which should be made up to 4000 ftp. The tong was moved up and the torque computer was reprogrammed. The programming was not completed as required. The tong operator then commenced making up the connection and didn’t see that the computer didn’t stop the tong at the required 4000 ftp, the current value is displayed on the screen. The mistake was not noted before 14000 ftp was applied. Due to the excess force applied it was decided to not run the sample carrier. Therefore, did not get any single phase bottom hole samples during the clean up phase.

What was planned:

RIH w/ DST string

What was learned:

May have been a human error, question was asked if it could have been avoided if the operator had a manual gauge, but it is questionable as the operator already had one display showing the torque value.

What actions are required:

Before future jobs one should evaluate if a backup carrier should be brought out. It has to be noted that there are several sample bottles in back-up. If the sample carrier has to be changed out the bottles would be transferred over to the backup carrier, approximately 2 hours work.