Page 4 - A Primer of Oilwell Service and Workover Completion
P. 4
FIGURES
Petroleum Extension-The University of Texas at Austin
. A newly drilled well lined . A conventional rotary . A production liner is run
with cemented casing system inside a previously run
. A reservoir can take many . Traveling block, hook, string of casing.
shapes. and swivel . A wire-wrapped screen, or
. A rock is porous when it . The kelly fits into the screen liner, is often
has many tiny spaces, or kelly bushing. combined with a gravel
pores. . The top drive hangs from pack inside perforated
. A rock is permeable when the the traveling block. casing.
pores are connected. . Joints of drill pipe are . The slotted liner is a pipe
. Reservoir fluids usually sepa- needed to reach the with holes in it.
rate into layers of gas, oil, and bottom of the hole. . Specially shaped wire wraps
water within . A drill bit is made up on around the slotted liner.
porous rock. the end of the drill string. . Gravel pack installation
. Artesian effect; water in . The circulating system . A packer goes around
the reservoir seeks its own sends drilling mud down tubing and seals the
level. the hole and back to the casing-tubing annulus.
. In a water-drive reservoir, wa- surface. . The sealing element of a
ter underneath the oil pushes . A. Compound, mechanical- packer is made of dense
it to the surface. drive rig synthetic rubber.
. Eventually, the water level B. Diesel electric-drive . The slips grip casing to
rises to fill the majority of the rig hold the packer in place.
reservoir. . A drill ship is usually used . The wellhead
. In a dissolved-gas drive reser- to drill exploratory wells in . A casinghead
voir, gas comes out of the oil, deep, remote waters. . Three casing strings
expands, and lifts hanging from two casing-
oil to the surface. . Concentric strings of casing heads
. In a gas-cap drive reservoir, line the drilled hole. . The tubing string hangs
free gas in the cap expands . An open-hole completion from a tubing head.
and pushes down on the oil allows reservoir fluids to . The Christmas tree is
to move it to the surface. flow into the uncased mounted on top of the
. In a gravity drainage reservoir, hole. tubing head.
oil may flow downhill to the . A jet perforating gun creates . Washing in the well replaces
well. holes, or perforations, in the drilling mud with salt
. The rotary drilling rig is a the casing and into the water.
collection of equipment and surrounding formation. . Injecting a high-pressure
machinery that drills . A shaped charge blasts a gas will often start the well
a well. high-energy jet stream flowing.
. The rig’s hoisting system through the casing, the
works like an old-fashioned cement, and into the
windlass. formation.
. The hoisting system
