| squeeze |
1. a cementing operation in which cement is
pumped behind the casing under high pressure to recement channeled areas or to block off
an uncementred zone. 2. the increasing of
external pressure on a diver's body caused by improper diving technique. |
| squeeze cementing |
the forcing of cement slurry by pressure to
specified points in a well to cause seals at the points of squeeze. It is a
secondary cementing method that is used to isolate a producing formation, seal off water,
repair casing leaks, and so forth. |
| squeeze job |
a remedial well-servicing activity whereby a
cement slurry is pumped into open perfs, split casing, etc., to effect a blockage. |
| squeeze manifold |
a type of manifold used in squeeze jobs. |
| squeeze packer |
a drillable service packer, a retainer. |
| squeeze tool |
a generic term to describe a retrievable
service packer. |
| SSV |
abbreviation: surface safety valve. |
| stab |
to guide the end of a pipe into a coupling
when making up a connection. |
| stabbing valve |
a special drill stem valve that, when in open
position, allows fluid to flow through it, thus allowing the valve to be stabbed into the
drill stem. |
| stability meter |
an instrument to measure the amount of voltage
needed to break down invert emulsions. |
| stabilized |
a well is considered "stabilized"
when, in the case of a flowing well, the rate of production through a given size of choke
remains constant, or, in the case of pumping well, when the fluid column within the well
remains constant in height. |
| stabilizer |
1. a tool placed on a drill collar near the
bit that is used, depending on where it is placed, either to maintain a particular hole
angle or to change the angle by controlling the location of the contact point between the
hole and the collars. See packed-hole assembly. 2. a vessel in which hydrocarbon vapors are separated from liquids.
3. a fractionation system that reduces the vapor pressure
so that the resulting liquid is less volatile. |
| stack |
1. a vertical arrangement of blowout
prevention equipment. Also called preventer stack. See blowout preventer.
2. the vertical chimney-like installation that is
the waste disposal system for unwanted vapor such as flue gases or tail-gas streams. |
| stack a rig |
to store a drilling rig on completion of a job
when the rig is to be withdrawn from operation for a time. |
| stage tool |
a sliding-sleeve ported casing section used in
stage cementing. |
| staging |
the placement of compressors, pumps, cooling
systems, treating systems, and so forth, in a series with another unit or units of like
design to improve operating efficiency and results. |
| stand |
the connected joints of pipe racked in the
derrick or mast during a trip. The usual stand is about 90 feet long (about 27
meters), which is three lengths of drill pipe screwed together (a thribble). |
| standing valve |
a fixed ball-and-seat valve at the lower end
of the working barrel of a sucker rod pump. The standing valve and its cage do not
move, as does the traveling valve. Compare traveling
valve. |
| standpipe |
a vertical pipe rising along the side of the
derrick or mast, which joins the discharge line leading from the mud pump to the rotary
hose and through which mud is pumped going into the hole. |
| starch |
a complex carbohydrate sometimes added to
drilling fluids to reduce filtration loss. |
| static |
opposite of dynamic. See quiescence. |
| static fluid
level |
the level to which fluid rises in a well when
the well is shut in. |
| steam drive |
a method of improved recovery in which steam
is injected into a reservoir through injection wells and driven toward production wells.
The steam reduces the viscosity of crude off, causing it to flow more freely.
The heat vaporizes lighter hydrocarbons; as they move ahead of the steam, they cool
and condense into liquids that dissolve and displace crude oil The steam provides
additional gas drive. This method is used to recover viscous oils. Also
called continuous steam injection or steam flooding. |
| steam flooding |
see steam
drive |
| stearate |
salt of stearic acid that is a saturated,
18-carbon fatty acid. Certain compounds, such as aluminum stearate, calcium
stearate, zinc stearate, have been used in drilling fluids for one or more of the
following purposes: defoamer, lubrication, air drilling in which a small amount of water
is encountered. |
| stimulation |
any process undertaken to enlarge old channels
or to create new ones in the producing formation of a well (e.g., acidizing or formation
fracturing). |
| stimulation valve |
a surge valve. |
| stinger |
1. a cylindrical or tubular projection,
relatively small in diameter, that extends below a downhole tool and helps to guide the
tool to a designated spot (such as into the center of a portion of stuck pipe). 2. a device for guiding pipe and lowering it to the water bottom as
it is being laid down by a lay barge. It is hinged to permit adjustments in the angle of
pipe launch. |
| stinging in |
the lowering of pipe or tubing into the bore
of a downhole tool. |
| stock tank oil |
oil as it exists at atmospheric conditions in
a stock tank. Stock tank oil lacks much of the dissolved gas present at reservoir
pressure and temperatures. |
| storage gas |
gas that is stored in an underground
reservoir. |
| Storm Choke |
a tubing safety valve. |
| stormer
viscometer |
a rotational shear viscometer used for
measuring the viscosity and gel strength of drilling fluids. This instrument has
been largely superseded by the direct-indicating viscometer. |
| storm packer |
a heavy-mandrel service squeeze tool with
on-off tool used in drilling operations during storm interruptions. |
| storm plug |
a retrievable tool used to suspend drilling
temporarily during a storm offshore. |
| straddle packer |
two packers separated by a spacer of variable
length. A straddle packer may be used to isolate sections of open hole to be treated
or tested or to isolate certain areas of perforated casing from the rest of the perforated
section. |
| streaming
potential |
the electrokinetic portion of the spontaneous
potential electric-log curve that can be influenced significantly by the characteristics
of the filtrate and mud cake or the drilling fluid that was used to drill the well. |
| streamline flow |
flow of a fluid in which no turbulence occurs.
The fluid follows a well-defined, continuous path. |
| string shot |
an explosive method utilizing primacord, which
is an instantaneous textile-covered fuse with a core of very high explosive. It is
used to create an explosive jar inside stuck drill pipe or tubing so that the pipe may be
backed off at the joint immediately above where it is stuck. |
| string up |
to thread the drilling line through the
sheaves of the crown block and traveling block. One end of the line is secured to
the hoisting drum and the other to the derrick substructure. |
| strip a well |
to pull rods and tubing from a well at the
same time. Tubing must be "stripped" over the rods a joint at a time. |
| stripper |
1. a well nearing depletion that produces a
very small amount of oil or gas, usually ten barrels per day or less. 2. a stripper head.
3. a column wherein absorbed constituents are stripped from
absorption off. The term is applicable to columns using a stripping medium, such as steam
or gas. |
| stripper head |
a blowout prevention device consisting of a
gland and packing arrangement bolted to the wellhead. It is often used to seal the
annular space between tubing and casing. |
| stripper rubber |
1. a rubber disk surrounding drill pipe or
tubing that removes mud as the pipe is brought out of the hole. 2. the pressure-sealing element of a stripper blowout
preventer See stripper head. |
| stripping in |
1. the process of lowering the drill stem into
the wellbore when the well is shut in on a kick and when the weight of the drill stem is
sufficient to overcome the force of well pressure. 2. the process of putting tubing into a well under pressure. |
| stripping out |
1. the process of raising the drill stem out
of the wellbore when the well is shut in on a kick. 2. the process of removing tubing from the well under pressure. |
| stuck pipe |
drill pipe, drill collars, casing, or tubing
that has inadvertently become immovable in the hole. Sticking may occur when
drilling is in progress, when casing is being run in the hole, or when the drill pipe is
being hoisted. |
| stuck point |
the depth in the hole at which the drill stem,
tubing, or casing is stuck. |
| stuffing box |
a device that prevents leakage along a piston,
rod, propeller shaft, or other moving part that passes through a hole in a cylinder or
vessel. It consists of a box or chamber made by enlarging the hole and a gland
containing compressed packing. On a well being artificially lifted by means of a
sucker rod pump, the polished rod operates through a stuffing box, preventing escape of
oil and diverting it into a side outlet to which is connected the flow line leading to the
oil and gas separator or to the field storage tank. For a bottomhole pressure test,
the wireline goes through a stuffing box and lubricator, allowing the gauge to be raised
and lowered against well pressure. The lubricator provides a pressure-tight grease
seal in the stuffing box. |
| strung up |
to have rigged up wire rope and sheaves or
blocks for hoisting. |
| sub |
a short, threaded piece of pipe used to adapt
parts of the drilling string that cannot otherwise be screwed together because of
differences in thread size or design. A sub (i.e., a substitute) may also perform a
special function. Lifting subs are used with drill collars to provide a shoulder to
fit the drill pipe elevators; a kelly saver sub is placed between the drill pipe and the
kelly to prevent excessive thread wear of the kelly and drill pipe threads, a bent sub is
used when drilling a directional hole. |
| sub elevator |
a small attachment on the rod-transfer
equipment that picks up the rods after they are unscrewed from the string and then
transfers them to the rod hanger, or reverses the procedure when going into the hole.
See rod-transfer equipment. |
| subsea
blowout preventer |
a blowout preventer placed on the seafloor for
use by a floating offshore drilling rig. |
| substructure |
the foundation on which the derrick or mast
and usually the drawworks sit. It contains space for storage and well-control
equipment. |
| sucker rod |
a special steel pumping rod. Several
rods screwed together make up the mechanical link from the beam pumping unit on the
surface to the sucker rod pump at the bottom of a well. Sucker rods are threaded on
each end and manufactured to dimension standards and metal specifications set by the
petroleum industry. Lengths are 25 or 30 feet (7.6 or 9.1 meters); diameter varies
from 1/2 to 1-1/8 inches (12 to 30 millimeters). There is also a continuous sucker
rod (tradename: Corod). |
| sucker rod pump |
the downhole assembly used to lift fluid to
the surface by the reciprocating action of the sucker rod string. Basic components
are barrel, plunger, valves, and hold-down. Two types of sucker rod pumps are the
tubing pump, in which the barrel is attached to the tubing, and the rod, or insert, pump,
which is run into the well as a complete unit. |
| sucker rod whip |
an undesirable whipping motion in the sucker
rod string that occurs when the string is not properly attached to the sucker rod pump or
when the pump is operated at a resonant speed. |
| suction pit |
also called a suction tank, sump pit, or mud
suction pit. See suction tank. |
| suction tank |
the mud tank from which mud is picked up by
the suction of the mud pumps. Also called a suction
pit. |
| suicide squeeze |
a squeeze cement job with open perfs above the
packer. |
| sulfamic acid |
a crystalline acid derived from sulfuric acid
that is sometimes used in acidizing. |
| supersaturation |
the condition of containing more solute in
solution than would normally be present at the existing temperature. |
| surface-active
agent |
see surfactant.
|
| surface pipe |
the first string of casing (after the
conductor pipe) that is set in a well. it varies in length from a few hundred to
several thousand feet. Some states require a minimum length to protect freshwater
sands. Compare conductor pipe. |
| surface tension |
the tendency of liquids to maintain as small a
surface as possible. It is caused by the cohesive attraction between the molecules
of liquid. |
| surfactant |
a soluble compound that concentrates on the
surface boundary between two substances such as oil and water and reduces the surface
tension between the substances. The use of surfactants permits the thorough surface
contact or mixing of substances that ordinarily remain separate. Surfactants are
used in the petroleum industry as additives to drilling mud and to water during chemical
flooding. See micellar-polymer
flooding; surfactant mud |
| surfactant mud |
a drilling mud prepared by adding a surfactant
to a water-base mud to change the colloidal state of the clay from that of complete
dispersion to one of controlled flocculation. Such muds were originally designed for
use in deep, high-temperature wells, but their many advantages (high chemical and thermal
stability, minimum swelling effect on clay-bearing zones, lower plastic viscosity, and so
on) extend their applicability. |
| surge loss |
the flux of fluids and solids that occurs in
the initial stages of any filtration before pore openings are bridged and a filter cake is
formed. Also called spurt loss. |
| surge valve |
a device employed with a packer to surge, or
clean, open perforations; also called surge disk. |
| surging |
a rapid increase in n pressure downhole that
occurs when the drill stem is lowered too fast or when the mud pump is brought up to speed
after starting. |
| suspensoid |
a mixture consisting of finely divided
colloidal particles floating in a liquid. The particles are so small that they do
not settle but are kept in motion by the moving molecules of the liquid (Brownian
movement). |
| swab |
a hollow, rubber-faced cylinder mounted on a
hollow mandrel with a pin joint on the upper end to connect to the swab line. A
check valve that opens upward on the lower end provides a way to remove the fluid from the
well when pressure is insufrficien5t to support flow. v: 1. to operate a swab on a wireline to bring well fluids to the surface when
the w4ell does not flow naturally. Swabbing is a temporary operation to determine
whether the well can be made to flow. If the well does not flow after being swabbed,
a pump is installed a a permanent lifting device to bring the oil to the surface.
2. to pull formation fluids into a wellbore by raising the
drill stem at a rate that reduces the hydrostatic pressure of the drilling mud below the
bit. |
| swab cup |
a rubber or rubber-like device on a special
rod (a swab), which forms a seal between the swab and the wall of the tubing or casing. |
| swage |
a tool used to straighten damaged or collapsed
casing in a well. |
| swamper |
a helper on a truck. |
| swedge |
a swage |
| sweet |
said of oil or gas when it contains no sour
impurities. |
| sweet corrosion |
the deterioration of metal caused by contact
with carbon dioxide in water. |
| sweet crude oil |
oil containing little or no sulfur, especially
little or no hydrogen sulfide. |
| switcher (obsolete) |
lease operator or pumper. |
| swivel |
a rotary tool that is hung from the rotary
hook and traveling block to suspend the drill stem and to permit it to rotate freely.
it also provides a connection fore the rotary hose and a passageway of the flow of
drilling fluid into the drill stem. |
| sx |
abbreviation: sacks; used in drilling
and mud reports. |
| synergistic
effect |
the added effect produced by two processes
working in combination. It is greater than the sum of the individual parts. |
