Page 420 - Practical Well Planning and Drilling Manual

Section 3 revised 11/00/bc 1/17/01 12:00 PM Page 396

[ ] Practical Wellsite Operations
3.4.4

Stuck pipe procedures. If the casing should become stuck while
running, the two likeliest causes are geometry related (high DLS or a
ledge) or differential. If mechanically stuck the only real choice is to
pull on the casing. For differential sticking, a Pipelax or similar pill can
be displaced. Refer to the stuck pipe topics in Section 3.3.1 for geom-
etry and differential sticking problems.
In high-angle or horizontal wells, the casing may push cavings or
cuttings ahead and build up a wall of debris that can then get you
packed off. Use a Tam packer or similar model, which will allow you
to commence circulating with the minimum of delay. Consider wash-
ing every joint down from about 65˚ inclination, taking care not to ini-
tiate lost circulation with high AVs/ECDs.
If you do get packed off while running casing, ensure you do have
closing pressure on the spider elevators, then work the casing to max-
imum pull and slack off to 25,000 lbs plus block weight (to maintain
some weight on the elevators). If possible leave some pressure on the
casing—this will give you a “pump out” force that will put more force
on the stuck point. If the debris starts to move, you will see the pres-
sure drop and eventually return. If you are lucky you may reinitiate full
circulation and clean up the annulus.
If you still remain stuck even though circulation was reestablished,
the chances of a good cement job in place are very low. You will still
have cuttings on the low side around the pipe (you may also be differ-
entially stuck) and the cement will channel along the high side.
Refer to the notes on stuck pipe relating to cuttings beds in Section
3.2.1, “Solids Control.”

396