points |
a method for indicating hook load
or force, read off rig's indicator; 1 point = 1,000 pounds |
pole mast |
a portable mast constructed of
tubular members. A pole mast may be a single pole, usually one or two different
sizes of pipe telescoped together to be moved or extended and locked to obtain maximum
height above a well. Double-pole masts give added strength and stability. See mast. |
polished
rod |
the topmost portion of a string of
sucker rods. It is used for lifting fluid by the rod-pumping method. It has a
uniform diameter and is smoothly polished to seal pressure effectively in the stuffing box
attached to the top of the well. |
polymer |
a substance that consists of large
molecules formed from smaller molecules in repeating structural units (monomers). In
oilfield operations, various types of polymers are used to thicken drilling mud,
fracturing fluid, acid, water, and other liquids. See micellar-polymer flooding,
polymer mud. In petroleum refining, heat and pressure are used to polymerize
light hydrocarbons into larger molecules, such as those that make up high-octane gasoline.
In petrochemical production, polymer hydrocarbons are used as a feedstock for
plastics. |
polymer mud |
a drilling mud to which a polymer
has been added to increase the viscosity of the mud. |
pony rod |
1. a sucker rod, shorter than
usual, used to make up a sucker rod string of desired length. Pony rods are usually
placed just below the polished rod. 2. the rod
joined to the connecting rod and piston rod in a mud pump |
POOH |
abbreviation:
pull-out-of-hole |
pool |
in general, the term
"pool" is synonymous with the term "reservoir"; however, in certain
situations, a pool may consist of more than one reservoir. |
poor boy |
homemade; something done on a
shoestring basis. |
poor
boy degasser |
slang for gas separator |
poor
boy gravel pack |
a bradenhead pack; no packer, very
limited pack pressure capability. |
poppet
valve |
a device that controls the rate of
flow of fluid in a line or opens or shuts off the flow of fluid completely. When
open, the sealing surface of the valve is moved away from a seat; when closed, the sealing
surface contacts the seat to shut off flow. The direction of movement of the valve
is usually perpendicular to the seat. Popper valves are used extensively as
pneumatic (air) controls on drilling rigs and as intake and exhausts valves in most
internal-combustion engines. |
pore |
an opening or space within a rock
or mass of rocks, usually small and often filled with some fluid (water, oil, gas, or all
three). Compare vug. |
pore
pressure |
see formation pressure |
porosity
(of a sand or sandstone) |
the percentage that the volume of
the pore space bears to the total bulk volume. The pore space determines the amount
of space available for storage of fluids. |
porous |
having pores, or tiny openings, as
in rock |
portable
mast |
a mast mounted on a truck and
capable of being erected as a single unit. See telescoping derrick. |
ported sub |
nipple; a device through which
fluid is circulated. |
portland
cement |
the cement most widely used in
oilwells. It is made from raw materials such as limestone, clay or shale, and iron
ore. |
positive
choke |
a choke in which the orifice size
must be changed to change the rate of flow through the choke. |
positive-displacement meter |
a mechanical fluid-measuring
device that measures by filling and emptying chambers of a specific volume. The
displacement of a fixed volume of fluid may be accomplished by the action of reciprocating
or oscillating pistons, rotating vanes or buckets, rotating disks, or tanks or other
vessels that automatically fill and empty. Also called a volume
meter or volumeter. |
posted barge submersible rig |
a mobile
submersible drilling structure consisting of a barge hull that rests on
bottom, steel posts that rise from the top of the barge hull, and a deck
that is built on top of the posts, well above the waterline. It is
used to drill wells in water no deeper than about 30-35 feet (9-10.7m).
Most posted barge submersibles work in inland gulfs and bays. |
potassium |
one of the alkali metal elements
with a valence of 1 and an atomic weight of about 39. Potassium compounds, most commonly
potassium hydroxide (KOH), are sometimes added to drilling fluids to impart special
properties, usually inhibition. |
potential |
the maximum volume of oil or gas
that a well is capable of producing, calculated from well test data. |
potential
test |
a test of the maximum rate at
which a well can produce oil. |
pound
equivalent |
a laboratory unit used in pilot
testing. One gram or pound equivalent, when added to 350 ml of fluid, is equivalent
to 1 lb/bbl. |
pounds
per gallon (ppg) |
a measure of the density of a
fluid (such as a drilling mud). |
pounds per square inch gauge (psig) |
the pressure in a vessel or
container as registered on a gauge attached to the container. This reading does not
include the pressure of the atmosphere outside the container. |
power rated |
rating given by a manufacturer of
an engine operating at most efficient output. |
power
rod tongs |
tongs that are actuated by air or
hydraulic fluid and are used for making up or breaking out sucker rods |
power sub |
a hydraulically powered device
used in lieu of a rotary to turn the drill pipe, tubing, or casing in a well. |
power
takeoff |
a gearbox or other device serving
to relay the power of a prime mover to auxiliary equipment. |
power tools |
equipment operated hydraulically
or by compressed air for making up and breaking out drill pipe, casing, tubing, and rods. |
ppg |
abbreviation: pounds per
gallon. |
ppm |
abbreviation: parts per
million |
precipitate |
a substance, usually a solid, that
separates from a fluid because of a chemical or physical change in the fluid. v: to
separate in this manner |
precipitation |
the production of a separate
liquid phase from a mixture of gases (e.g., rain), or of a separate solid phase from a
liquid solution, as in the precipitation of calcite cement from water in the interstices
of rock. |
preservative |
usually paraformaldehyde.
Any material used to prevent starch or any other substance from fermenting through
bacterial action. |
pressure |
the force that a fluid (liquid or
gas) exerts uniformly in all directions within a vessel, pipe, hole in the ground, and so
forth, such as that exerted against the inner wall of a tank or that exerted on the bottom
of the wellbore by a fluid. Pressure is expressed in terms of force exerted per unit
of area, as pounds per square inch, or in kilopascals. |
pressure
control |
commonly referred to as snubbing;
running of tool and/or pulling of tubing under well pressure. |
pressure
drop |
a loss of pressure that results
from friction sustained by a fluid passing through a line, valve, fitting, or other
device. |
pressure-drop
loss |
the pressure lost in a pipeline or
annulus due to the velocity of the liquid in the pipeline, the properties of the fluid,
the condition of the pipe wall, and the alignment of the pipe. In certain mud-mixing
systems, the loss of head can be substantial |
pressure
gauge |
an instrument that measures fluid
pressure and usually registers the difference between atmospheric pressure and the
pressure of the fluid by indicating the effect of such pressures on a measuring element
(e.g., a column of liquid, pressure in a Bourdon tube, a weighted piston, or a diaphragm). |
pressure
gradient |
1. a scale of pressure differences
in which there is a uniform variation of pressure from point to point. For example,
the pressure gradient of a column of water is about 0.433 pounds per square inch per foot
(9.794 kilopascals per meter) of vertical elevation. The normal pressure gradient in
a formation is equivalent to the pressure exerted at any given depth by a column of 10
percent salt water extending from that depth to the surface 0.465 pounds per square inch
per foot or 10.518 kilopascals per meter). 2.
the change (along a horizontal distance) in atmospheric pressure. Isobars drawn on
weather maps display the pressure gradient. |
pressure-integrity
test |
a method of determining the amount
of pressure that is allowed to appear on the casing pressure gauge as a kick is circulated
out of a well. In general, it is determined by slowly pumping mud into the well
while it is shut in and observing the pressure at which the formation begins to take mud. |
pressure
loss |
1. a reduction in the amount of
force a fluid exerts against a surface, such as the walls of a pipe. It usually occurs
because the fluid is moving against the surface and is caused by the friction between the
fluid and the surface. 2. the amount of
pressure indicated by a drill pipe pressure gauge when drilling fluid is being circulated
by the mud pump. Pressure losses occur as the fluid is circulated. |
pressure
maintenance |
repressuring of an oil-field to
maintain original pressure. The use of water flooding or natural gas recycling during
primary recovery to provide additional formation pressure and displacement energy that can
supplement and conserve natural reservoir drives. Although commonly begun during primary
production, pressure maintenance methods are often considered to be a form of enhanced oil
recovery. |
pressure
probe |
a diagnostic tool used to
ascertain whether there is a gas leak in the tubing of a gas lift well. If there is
a tubing leak, the pressure on the annulus will equal the pressure on the tubing. |
pressure
regulator |
a device for maintaining pressure
in a line, downstream from the value. |
pressure
relief valve |
a valve that opens at a preset
pressure to relieve excessive pressures within a vessel or line. Also called a relief valve, safety valve, or safety relief valve. |
pressure
surge |
a sudden, usually short-duration,
increase in pressure. When pipe or casing is run into a hole too rapidly, an
increase in the hydrostatic pressure results, which may be great enough to create lost
circulation |
pressure, volume, and temperature (PVT) analysis |
an examination of reservoir fluid
in a laboratory under various pressures, volumes, and temperatures to determine the
characteristics and behavior of the fluid. |
primary
cementing |
the cementing operation that takes
place immediately after the casing has been run into the hole. It provides a
protective sheath around the casing, segregates the producing formation, and prevents the
undesirable migration of fluids. |
primary
recovery |
the first stage of oil production
in which natural reservoir drives are used to recover oil, although some form of
artificial lift may be required to exploit declining reservoir drives. |
primary
well control |
prevention of formation fluid flow
by maintaining a hydrostatic pressure equal to or greater than formation pressure |
prime mover |
an internal-combustion engine or a
turbine that is the source of power for driving a machine or machines. |
producing
zone |
the zone or formation from which
oil or gas is produced. See pay sand. |
production |
the yield of an oil or gas well;
the branch of the industry that brings the oil and gas to the surface for sale. The phase
of the petroleum industry that deals with bringing the well fluids to the surface and
separating them and with storing, gauging, and otherwise preparing the product for
pipeline. The amount of oil or gas produced in a given period. |
production
packer |
any packer designed to make a seal
between the tubing and the casing during production |
production
rig |
a portable servicing or workover
outfit, usually mounted on wheels and self-propelled. A well servicing unit consists
of a hoist and engine mounted on a wheeled chassis with a self-erecting mast. A
workover rig is basically the same, with the addition of a substructure with rotary, pump,
pits, and auxiliaries to permit handling and working a drill string. |
production
seal unit |
same as seal nipple assemblies. |
production
tank |
a tank used in the field to
receive crude oil as it comes from the well. Also called a flow tank or lease tank. |
production
test |
a test of the well's producing
potential usually done during the initial completion phase |
production
tubing |
a string of tubing used to produce
the well, providing well control and energy conservation. |
propane |
a paraffinic hydrocarbon that is a
gas at ordinary atmospheric conditions but is easily liquefied under pressure. It is
a constituent of liquefied petroleum gas. |
proppant |
see propping
agent |
propping
agent |
a granular substance (sand grains,
aluminum pellets, or other material) that is carried in suspension by the fracturing fluid
and that serves to keep the cracks open when fracturing fluid is withdrawn after a
fracture treatment. |
props |
proppants, beads, sand used in
hydraulic fracturing operations. |
proration |
a system of allocating production
on a per well basis. |
PSA |
abbreviation: a generic
term for pressure setting assembly; a tool that is used to set permanent tools on electric
wireline, through explosive force. |
pseudoplastic |
having the capability of changing
apparent viscosity with a change in shear rate. Pseudoplastic fluids gain viscosity
when subjected to a decrease in shear rate, and lose viscosity when the shear rate is
increased. See shear. |
psi |
abbreviation: pounds per
square inch |
psia |
abbreviation: pounds per
square inch absolute. See absolute
pressure. |
psi/ft |
abbreviation: pounds per
square inch per foot. |
psig |
abbreviation: pounds per
square inch, gauge. |
PTO |
abbreviation: power take
off. |
pull
the trigger |
to fire a wireline-operated
downhole tool from inside the service truck. |
pulling
tool |
a hydraulically operated tool that
is run in above the fishing tool and anchored to the casing by slips. It exerts a
strong upward pull on the fish by hydraulic power derived from fluid that is pumped down
the fishing string. |
pulling
unit |
a well-servicing outfit used in
pulling rods and tubing from the well. See production
rig. |
pump |
a device that increases the
pressure on a fluid or raises it to a higher level. Various types of pumps include
the bottomhole pump, centrifugal pump, hydraulic pump, jet pump, mud pump, reciprocating
pump, rotary pump, sucker rod pump, and submersible pump |
pump-down |
descriptive of any tool or device
that can be pumped down a wellbore. Pump-down tools are not lowered into the well on
wireline; instead, they are pumped down the well with the drilling fluid. |
pumping tee |
a heavy-duty steel, T-shaped pipe
fitting that is screwed or flanged to the top of a pumping well. The polished rod
works through a stuffing box on top of the tee and in the run of the tee to operate a
sucker rod pump in the well. Pumped fluid is discharged through the side opening of
the tee. |
pump jack |
a surface unit similar to a
pumping unit but having no individual power plant. Usually, several pump jacks are
operated by pull rods or cables from one central power source. Commonly, but
erroneously, beam pumping units are called pump jacks. Compare beam pumping unit. |
pump liner |
a cylindrical, accurately
machined, metallic section that forms the working barrel of some reciprocating pumps.
Liners are an inexpensive means of replacing worn cylinder surface, and in some
pumps they provide a method of conveniently changing the displacement and capacity of the
pumps. |
pump
manifold |
an arrangement of valves and
piping that permits a wide choice in the routing of suction and discharge fluids among two
or more pumps |
pump off |
to pump so rapidly that the oil
level drops below the standing valve on the pump. |
pump-out
plug |
a device to provide running the
tubing dry with a packer released by elevating tubing pressure, thereby opening the tubing
to formation pressure. |
pup joint |
a length of drill or line pipe,
tubing, or casing considerably shorter than 30 feet. |
put a well
on |
to start a well flowing or
pumping. |
put on pump |
to install a pump or pumping unit,
sucker rods, and bottom-hole pump. |
PVT |
abbreviation: 1. Pit Volume Totalizer.
2. pressure, volume, and temperature. |