Page 372 - Practical Well Planning and Drilling Manual

Section 3 revised 11/00/bc 1/17/01 12:00 PM Page 348

[ ] Practical Wellsite Operations
3.3.1

Tight hole is potential stuck pipe. Do not try to save time by ignor-
ing the signs; this approach will usually result in getting stuck.
Where hole conditions exist that make stuck pipe likely, the
drilling supervisor must be on the drillfloor while tripping through the
problem sections. In any case, the supervisor should be present for the
initial flowcheck and the trip out as far as the previous trip depth.
BP put together a task force some years ago to examine the stuck
pipe problem and came up with recommendations to drastically reduce
the incidence of stuck pipe. One of the more interesting findings we
made was that a disproportionate number of cases occurred within the
two hours after a shift change. This led to the advice “brief your relief.”
Clearly the handover between drillers was somehow deficient, which
led to the new driller on shift being unaware of vital information need-
ed to recognize incipient stuck pipe in time.
Most cases of stuck pipe are avoidable with proper supervision,
and once stuck pipe is recognized, fast action is necessary. The best
chance of getting free is just after getting stuck. Take the time to fully
brief the drillers on the procedures you expect to be followed, includ-
ing when you should be called if there are problems.
A good handover between drillers is essential since a dispropor-
tionate number of stuck pipe incidents occur within two hours of a
shift change. The toolpusher or night pusher should be on the floor at
handover time to allow the drillers time for a good handover, and it is
a good idea for the drilling supervisor to be around at this time as well.
The drillers, toolpusher, and drilling supervisor should always
know the allowable pull on the pipe (with and without the kelly on).
There will not be time to work it out when you get stuck.
Undergauge hole. Ream any tight spots on trips. Ream back to bot-
tom after changing the bit and/or BHA, the last 10 to 30 m depending on
hole conditions. If deviation or other considerations permit, ream once
each single before making a connection, which will also clean around
the BHA before shutting the pumps off (which is good practice anyway).
If the hole should become undergauge above the BHA due to wall
cake formation or mobile formations, it will probably be necessary to
circulate and backream out. If the slips are used to backream with a
kelly, take all proper safety precautions; tie the slip handles together
when set, and never pick up out of the slips with torque left on the table.
Keep personnel off the drillfloor as much as possible. Avoid picking up
so much that the string torques up and stalls out while reaming.

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