Page 14 - A Primer of Oilwell Service and Workover Completion

WELL SERVICING AND REPAIR 



Petroleum Extension-The University of Texas at Austin

WELL SERVICING AND REPAIR

ells require maintenance The most common service and Another maintenance check
Wand repairs from time to repair jobs include swabbing and is to assure that the cranks are
time due to normal wear, age, repairing or replacing sucker rod correctly counterbalanced.
and hazards of the environ- pumps, sucker rods, production Improper weight can cause dam-
ment to which the equipment tubing, and packers. (The next age to the gear teeth.
is exposed. Downhole pumps, chapter describes another type of
sucker rods, and gas-lift equip- servicing job, fishing.) Sucker Rods and Pumps
ment all have moving parts,
which wear out because of ero- REPAIRING BEAM Sucker rods, their couplings,
sion from the fast-moving res- PUMPING EQUIPMENT and sucker rod pumps can fail
ervoir fluid, which may contain because of corrosion and scale,
sand or particles of metal left Modern beam pumping units erosion and wear, careless han-
from perforating, for example. perform for a long time with dling, or stress from the pump’s
Production tubing also corrodes. proper care and when not movement. Often, more than
Both moving and stationary overloaded. Proper care means one of these factors is at work.
equipment can fail because of regular lubrication of the mov- To service, repair, or replace
corrosion, scale, and paraffin ing parts and seasonal changes the rods or pump, a crew pulls
deposits. of the oil in the speed reducer. the sucker rod string out of the
Lease operators are usu- Many rig operators choose not to well. For a tubing pump crew-
ally the first to notice abnormal change the oil unless it appears to members must also pull the tub-
conditions in the well that sug- be dirty; however, they pull the ing, and for an insert pump they
gest the need for repair work. drain plug on the speed reducer pull only the sucker rod string.
Routine tests and well reports on to drain any condensation.
daily production, wellhead pres-
sure, and percentage of water in
the oil provide evidence of the
need for maintenance or repair.

