8 weeks 4 hours
Preparing for U1332
Submitted by Adam Klaus on Tue, 03/24/2009 - 23:46
Here's an explanation with new vocabulary to help you prepare for Site U1332. See Ron's updates for more about locations and plans.
TRIPPING PIPE: It will take us about nine hours to “trip” the drill string back out of the hole and back onto the ship. “Tripping” simply means raising or lowering the drill string. Once the drill pipe is all back on board, broken up into the 30 m long stands, and layed down in the pipe racker, we’ll start to partially take apart the BHA (bottom hole assembly). The BHA will not be taken completely apart, but separated into ~30 m long stands, stood up vertically on the rig floor, and secured for transit. This way we will not have to reassemble the BHA from the individual pieces and save time at our next site. Then we’ll re-attach the bit and then do it all in reverse!
SLIP AND CUT and TON-MILES: Around dinner time (mine), we had to pause tripping the drill sting to “cut and slip” the drill line. The drill line is the VERY thick cable that raises and lowers the entire drill string (>600,000 lbs -- see my last blog). During drilling operations the same section of it goes back and forth over the crown sheave at the top of the derrick. About every 4400 ton-miles, we need to “slip and cut” the drill line. This simply means that we have to cut off ~35m of the drill line, so the same part of the drill line doesn’t wear out over the crown sheave. Slipping and cutting only takes a couple of hours. Ton-miles is my favorite unit! I figure my knees only have so many ton-miles; I’m planning to go many miles, so I have to minimize my weight so they don’t wear out!
Challenge: What is a ton-mile? Send your answers through the Comment function below.
SITE U1332 (PEAT-2C) The overall the plan at our next site is very similar to the one we just completed at Site U1331.
More core to come,