back-in
unit |
a portable servicing or workover
rig that is self-propelled, using the hoisting engines for motive power. Because the
driver's cab is mounted on the end opposite the mast support, the unit must be backed up
to the wellhead. See carrier rig.
|
back
pressure |
the pressure resulting from
restriction of full natural flow of oil or gas. |
back-off |
to unscrew. |
back-up man |
the person who holds one length of
pipe while another length is being screwed into or out of it. |
back-pressure |
1. the pressure maintained on
equipment or systems through which a fluid flows. 2. in reference to engines, a term used to describe the resistance to the flow of
exhaust gas through the exhaust pipe.
3. the operating pressure level measured downstream from a
measuring device. |
back-pressure
valve |
1. a valve used to regulate
back-pressure on equipment or systems through which a fluid flows. 2. a valve used to regulate automatically a uniform pressure on the
inlet side of the valve. |
backside |
the area above a packer between
casing ID and tubing OD |
back up |
to hold one section of an object
such as pipe while another section is being screwed into or out of it. |
backup
element |
a sealing ring on either side of
the center packing element to limit its extrusion |
backup ring |
a cylindrical ring, usually
vise-shaped, employed to back up (or assist) a sealing member against extrusion under
temperature and pressure. |
baffles |
plates which change the direction
of flow of fluids. |
bail |
1. a curved steel rod on top of
the swivel that resembles the handle, or bail, of an ordinary bucket, but is much larger.
Just as an ordinary bucket is hung from a hook by its bail, the swivel is hung from the
traveling block's hook by its bail. Sometimes, the two steel rods (the links) that attach
the elevator to the hook are also called bails. 2.
to recover bottomhole fluids, samples, mud, sand, or drill cuttings by lowering a
cylindrical vessel called a bailer to the bottom of a well, filling it, and retrieving it. |
bailer |
a long, cylindrical container
fitted with a valve at its lower end, used to remove water, sand, mud, drilling cuttings,
or oil from a well in cable-tool drilling. |
ball |
a spherical object used to pump
down the drill string or tubing to trip, release, or otherwise operate certain
hydraulic-type tools. |
ball and
seat |
the main parts of the valves in a
plunger-type oil-well pump. |
ball-and-seat
valve |
a device used to restrict fluid
flow to one direction. It consists of a polished sphere, or ball, usually or metal,
and an annular piece, the seat, ground and polished to form a seal with the surface of the
ball. Gravitational force or the force of a spring holds the ball against the seat.
Flow in the direction of the force is presented, while flow in in the opposite
direction overcomes the force and unseats the ball. |
ball
catcher |
a tube placed around the
retrieving neck of a retrievable bridge plug to "catch" debris. |
ball-out |
to plug open perforations by using
ball sealers. |
ball
sealers |
balls made of nylon, hard rubber,
or both and used to shut off perforations through which excessive fluid is being lost. |
ball up |
1. to collect a mass of sticky
consolidated material, usually drill cuttings, on drill pipe, drill collars, bits, and so
forth. A bit with such material attached to it is called a balled-up bit.
Balling up is frequently the result of inadequate pump pressure or insufficient drilling
fluid. 2. in reference to an anchor, to fail
to hold on a soft bottom, pulling out, instead, with a large ball of mud attached. |
ball valve |
a flow-control device employing a
ball with a rotating mechanism to open or close the tubing medium. |
ballast |
1. for ships, water taken onboard
into specific tanks to permit proper angle of repose of the vessel in the water, and to
assure structural stability. 2. for mobile
offshore drilling rigs, weight added to make the rig more seaworthy, increase its draft,
or sink it to the seafloor. Seawater is usually used for ballast, but sometimes
concrete or iron is used additionally to lower the rig's center of gravity permanently. |
barefoot
completion |
see open-hole completion |
barite |
barium sulfate; a mineral
frequently used to increase the weight or density of drilling mud. Its relative
density is 4.2 (or 4.2 times denser than water). See barium
sulfate, mud. |
barite plug |
a settled volume of barite
particles from a barite slurry placed in the wellbore, usually to seal off a pressured
zone. |
barite
slurry |
a mixture of barium sulfate,
chemicals, and water of a unit density between 18 and 22 pounds per gallon |
barium
sulfate |
a chemical combination of barium,
sulfur, and oxygen which forms a tenacious scale that is very difficult to remove.
See barite. |
barrel
(bbl) |
1. a measure of volume for
petroleum products in the United States. One barrel is the equivalent of 42 U.S.
gallons or 0.15899 cubic meters (9,702 cubic inches). One cubic meter equals 6.2897
barrels. 2. the cylindrical part of a sucker
rod pump in which the piston-like plunger moves up and down. Operating as a piston
inside a cylinder, the plunger and barrel create pressure energy to lift well fluids to
the surface. |
barrels
per day (bpd) |
in the United States, a measure of
the rate of flow of a well; the total amount of oil and other fluids produced or processed
per day. |
barrel
equivalent |
a laboratory unit used for
evaluating or testing drilling fluids. One gram of material, when added to 350
milliliters of fluid, is equivalent to 1 pound of material when added to one 42-gal barrel
of fluid. |
barrel
wrench |
a friction wrench used in
repairing oil-well pumps |
baryte |
variation of barite. See barite. |
base |
a substance capable of reacting
with an acid to form a salt. A typical base is sodium hydroxide (caustic), with the
chemical formula MOH. For example, sodium hydroxide combines with hydrochloric acid
to form sodium chloride (a salt) and water. |
base
exchange |
the replacement of cations
associated with the clay surface by those of another species, e.g., the conversion of
sodium clay to calcium clay. |
basicity |
pH value above 7 and the ability
to neutralize or accept protons from acids |
basket |
a device employed to catch debris
from drillable tools, perforators, and so on |
basket
grapple |
an expandable, cylindrically
shaped gripping mechanism that is fitted into an overshot to retrieve fish from the
borehole. See grapple. |
basket sub |
a fishing accessory run above a
bit or a mill to recover small, nondrillable pieces of metal or junk. |
batch |
a definite amount of oil, mud,
acid, or other liquid in a tank or pipe. |
batch
treating |
the process by which a single
quantity of crude oil emulsion is broken into oil and water. The emulsion is
gathered and stored in a tank or container prior to treating. |
battery |
1. an installation of identical or
nearly identical pieces of equipment (such as a tank battery or a battery of meters). 2. an electricity storage device. |
bbl |
abbreviation: barrel |
b/d |
abbreviation: barrels per
day; often used in drilling reports |
beam |
the walking beam of a pumping
unit. |
beam
pumping unit |
a machine designed specifically
for sucker rod pumping. An engine or motor (prime mover) is mounted on the unit to
power a rotating crank. The crank moves a horizontal member (walking beam) up and
down to produce reciprocating motion. This reciprocating motion operates the pump.
Compare pump jack |
beam well |
a well using a pumping unit and
rods to lift fluid. |
bean |
a choke, used to regulate flow of
fluid from a well. Different sizes of beans are used for different producing rates. |
belching |
a slang term to denote flowing by
heads |
bell hole |
a bell-shaped hole dug beneath a
pipeline to provide room for use of tools. |
bell nipple |
a short length of pipe (a nipple)
installed on top of the blowout preventer. The top end of the nipple is flared, or
belled, to guide drill tools into the hole and usually has side connections for the fill
line and mud return line. |
bentonite |
a colloidal clay, composed
primarily of montmorillonite, that swells when wet. Because of its gel forming
properties, bentonite is a major component of water-based drilling muds. See gel, mud. |
bent sub |
a short cylindrical device
installed in the drill stem between the bottom-most drill collar and a downhole motor.
Its purpose is to deflect the downhole motor off vertical to drill a directional
hole. See drill stem. |
bicarb |
see sodium bicarbonate |
bird cage |
to flatten and spread the strands
in a wire rope. |
bird-dog |
to supervise another too closely
or continuously |
bit |
the cutting or boring element used
in drilling oil and gas wells. This bit consists of a cutting element and a
circulating element. The circulating element permits the passage of drilling fluid
and utilized the hydraulic force of the fluid stream to improve drilling rates. In
rotary drilling, several drill collars are joined to the bottom end of the drill pipe
column, and the bit is attached to the end of the string of drill collars. Most bits
used in rotary drilling are roller cone bits, but diamond bits are also used extensively. |
blank
casing |
casing without perforations |
blank
flange (also a blind flange) |
a solid disc used to dead end a
companion flange. |
blank joint |
a heavy wall sub placed opposite
flowing perforations. |
blank liner |
a liner without perforations. |
blank-off |
to close off, such as with a blank
flange or bull plug. |
blast joint |
a tubing sub made of
abrasion-resistant material. It is used in a tubing string where high-velocity flow
through perforations may cause external erosion. |
bleed |
to drain off liquid or gas,
generally slowly, through a valve called a bleeder. To bleed down, or bleed off,
means to release pressure slowly from a well or from pressurized equipment. |
bleed into |
to cause a gas or liquid to mingle
slowly with another gas or liquid usually by pressure. |
bleed line |
a pipe through which pressure is
bled, as from a pressurized tank, vessel, or other pipe. |
bleed
off or bleed down |
reduce pressure by letting oil or
gas escape at a low rate. |
bleeder |
a valve or pipe through which
bleeding is done. |
blender |
a device used to blend slurries or
gels, usually mobile equipment. |
blind ram |
an integral part of a blowout
preventer, which serves as the closing element on an open hole. Its ends do not fit
around the drill pipe but seal against each other and shut off the space below completely.
See ram |
block |
an assembly of pulleys on a common
framework; in mechanics, one or more pulleys, or sheaves, mounted to rotate on a common
axis. The crown block is an assembly of sheaves mounted on beams at the top of the
derrick. The drilling line is reeved over the sheaves of the crown block alternately
which the sheaves of the traveling block, which is raised and lowered in the derrick by
the drilling line. When elevators are attached to a hook on the traveling block and
drill pipe latched in the elevators, the pipe can be raised or lowered. See crown block and traveling block. |
blocks |
heavy lifting mechanism used on
rigs to provide a mechanical pulling and running advantage. |
blooey line |
the discharge pipe from a well
being drilled by air drilling. The blooey line is used to conduct the air or gas
used for circulation away from the rig to reduce the fire hazard as well as to transport
the cuttings a suitable distance from the well. |
blowdown |
1. the emptying or depressurizing
of material in a vessel. 2. the material thus
discarded. |
blowout |
an uncontrolled flow of gas, oil,
or other well fluids into the atmosphere or into an underground formation. A
blowout, or gusher, can occur when formation pressure exceeds the pressure applied to it
by the column of drilling fluid. |
blowout
preventer |
one of several valves installed at
the wellhead to prevent the escape of pressure either in the annular space between the
casing and drill pipe or in open hole (i.e., hole with no drill pipe) during drilling
completion operations. Blowout preventers on land rigs are located beneath the rig
at the land's surface; on jackup or platform rigs, at the water's surface; and on floating
offshore rigs, on the seafloor. |
blowout preventer control panel |
controls, usually located near the
driller's position on the rig floor, that are manipulated to open and close the blowout
preventers. See blowout preventer. |
blowout preventer control unit |
a device that stores hydraulic
fluid under pressure in special containers and provides a method to open and close the
blowout preventers quickly and reliably. Usually, compressed air and hydraulic
pressure provide the opening and closing force in the unit. See blowout preventer. |
blowout
preventer drill |
a training procedure to determine
that rig crews are completely familiar with correct operating practices to be followed in
the use of blowout prevention equipment. A "dry run" of blowout
preventative action. |
blowout preventer operating and control system |
the assembly of pumps, valves,
lines, accumulators, and other items necessary to open and close the blowout preventer
equipment. Also called closing unit. |
blowout
preventer rams |
the closing and sealing components
of a preventer, like the gate in a gate valve. |
blowout
preventer stack |
the assembly of well-control
equipment including preventers, spools, valves, and nipples connected to the top of the
wellhead. |