Oil & Gas Glossary 1.0

A manually operated ram preventer especially adapted for closure around a wireline.

A manually operated ram preventer especially adapted for closure around a wireline.

A manually operated ram preventer especially adapted for closure around a wireline.

Preventers installed on top of the well or drill string as a precautionary measure while running wirelines. The preventer packing will close around the wireline.

1. to force pipe or tools into a high-pressure well that has not been killed (i.e., to run pipe or tools into the well against pressure when the weight of pipe is not great enough to force the pipe through the BOPs). Snubbing usually requires an array of wireline bocks and wire rope that forces the pipe or tools into the well through a stripper head or blowout preventer until the weight of the string is sufficient to overcome the lifting effect of the well pressure on the pipe in the preventer. In workover operations, snubbing is usually accomplished by using hydraulic power to force the pipe through the stripping head or blowout preventer.

A blowout preventer that uses rams to seal off pressure on a hole that is with or without pipe. Also called a ram preventer.

2. in wireline, trying to pull out of the well faster than the wireline tools are being blown upwards by unexpected pressure.

A flared-end sub run on the end of the tubing string to permit easy access of wireline tools into the tubing ID.

A flared-end sub run on the end of the tubing string to permit easy access of wireline tools into the tubing ID.

A bottomhole choke run on wireline and landed in a nipple profile in the tubing string.

The closing and sealing components of a preventer, like the gate in a gate valve.

The assembly of pumps, valves, lines, accumulators, and other items necessary to open and close the blowout preventer equipment. Also called closing unit.

A blowout preventer placed on the seafloor for use by a floating offshore drilling rig.

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.

A small-diameter metal line used in wireline operations. Also called slick line. Compare conductor line.

A blowout preventer that uses shear rams as closing elements.

A cable composed of steel wires twisted around a central core of fiber or steel wire to create a rope of great strength and considerable flexibility. Wire rope is used as drilling line (in rotary and cable-tool rigs), coring line, servicing line, winch line, and so on. It is often called cable or wireline; however, wireline is a single, slender metal rod, usually very flexible. Compare wireline.

A small-diameter conductive line used in electric wireline operations, such as electric well logging and perforating, in which the transmission of electrical current is required. Compare wireline.

A preventer having a unit of packing material whose closure depends on well pressure coming from below. It is used primarily to strip pipe through the hole or allow pipe to be moved with pressure on the annulus.

A sealing component for a blowout preventer that closes the annular space between the pipe and the blowout preventer or wellhead.

A pulley that is normally attached to the wellhead at a convenient place for the wireline to pass through as it comes from the stuffing box sheave before being spooled onto the wireline reel. The hay pulley prevents any lateral force from being exerted on the lubricator and the wellhead.

A formation fluid sampling device, actually run on conductor line rather than wireline, that also logs flow and shut-in pressure in rock near the borehole. A spring mechanism holds a pad firmly against the sidewall while a piston creates a vacuum in a test chamber. Formation fluids enter the tes5t chamber through a valve in the pad. A recorder logs the rate at which the test chamber is filled. Fluids may also be drawn to fill a sampling chamber. Wireline formation tests may be done any number of times during one tip in the hole, so they are very useful in formation testing.

1. a vertical arrangement of blowout prevention equipment. Also called preventer stack. See blowout preventer.

See ram blowout preventer.

A blowout preventer that uses pipe rams as the closing elements. See pipe ram.

A device placed or hung in the casing below the blowout preventer stack to form a pressure tight seal. Pressure is then applied to the blowout preventer stack to test it for leaks

Any valve installed in the drill stem to prevent a blowout through the stem. Mud can be pumped in but flow back up the stem is prevented. Also called an internal blowout preventer.

A pipe attached to the blowout preventer stack out of which kick fluids and mud can be pumped to the choke manifold when a blowout preventer is closed in on a kick.

A portable mast that an be erected as a unit, usually by a tackle that hoists the wireline or by hydraulic pistons. The upper section of a telescoping derrick is generally nested (telescoped) inside the lower section of the structure and raised to full height either by the wireline or by a hydraulic system.

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.

A dart-shaped drill pipe inside blowout preventer installed on top of the drill stem when the well is kicking through the drill stem. It is stabbed in open then closed against pressure.

Abbreviation: blowout preventer.

Abbreviation: blowout preventer equipment

See inside blowout preventer.

A general term often used to refer to any type of log being run in a well. See log.

A general term often used to refer to any type of log being run in a well.

A device to connect the wireline to the tool string.

In drilling, to assemble the blowout preventer stack on the wellhead at the surface.

A diagnostic tool used to ascertain the position of a gas leak in the tubing of a gas lift well.

2. to force a wireline tool or tubing down the hole by using a reciprocating motion.

A diagnostic tool used to ascertain the position of a gas leak in the tubing of a gas-lift well.

A ram device used to close the annular space around the polished rod or sucker rod in a pumping well.

To fire a wireline-operated downhole tool from inside the service truck.

N. 1. a piece of cloth, rope or nylon strand used to mark the wireline when swabbing or bailing.

A ported, extended production tub used as an alternative path for wireline measuring devices.

The wireline attached to ground anchors to provide lateral support for a mast or derrick.

Abbreviation: a generic term for pressure setting assembly; a tool that is used to set permanent tools on electric wireline, through explosive force.

The assembly of well-control equipment including preventers, spools, valves, and nipples connected to the top of the wellhead.

The assembly of pumps, valves, lines, accumulators, and other items necessary to open and close the blowout preventer equipment.

2. in swabbing or bailing, to attach a piece of cloth to the wireline to enable the operator to estimate the position of the swab or bailer in the well.

A wireline attached to a mast, derrick, or offshore platform to stabilize it. See wind guy line.

A device closed around the rods when the well may flow through the tubing while the rods are being pulled. It is a form of blowout preventer.

A tool used to gauge and clean junk and debris from the casing in conjunction with a junk catcher.

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

A valve in the bottom of a retainer. See wireline.

2. to lower or raise tools in or out of a well with pressure inside the well. The term comes from the fact that a lubricant (grease) is often used to provide a seal against well pressure while allowing wireline to move in or out of the well.

2. to lower or raise tools in or out of a well with pressure inside the well. The term comes from the fact that a lubricant (grease) is often used to provide a seal against well pressure while allowing wireline to move in or out of the well.

A device used to measure the depth of a well or the depth at a specific point in a well (such as to the top of a liner or to a fish) by counting the turns of a calibrated wheel rolling on a wireline as it is lowered into or pulled out of the well.

The joint of drill pipe that is used in hang-off operations so that no tool joint is opposite a set of preventer rams.

2. the pressure-sealing element of a stripper blowout preventer See stripper head.

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.

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.

An extension from the blowout preventer assembly used to direct control the flow of well fluids from the annulus to the choke.

The ratio between the pressure in the hole and the operating-piston pressure needed to close the rams of a blowout preventer.

A poppet spring-loaded subsurface valve run in on wireline, landed in a profile, to shut the well if injection ceases.

A cylindrical or spherical device that is affixed to the end of a wireline just above the hook to keep the line straight and to provide weight. v: to soak metal pieces in a chemical solution to remove dirt and scale from the metal's surface.

A wireline used on drilling rigs and well servicing rigs to operate a swab or bailer, to retrieve cores or to run logging devices. It is usually 9/16 of an inch (15 millimeters) in diameter and several thousand feet or meters long

A wireline pressure setting tool for setting permanent downhole tools.

A heavy weight or bar placed on or near a lightweight wireline tool. The bar provides weight so that the tool will lower properly into the well.

1. a large valve located on the Christmas tree and used to control the flow of oil and gas from a well. Also called master gate. 2. the blind or blank rams of a blowout preventer (obsolete).

The ratio between the pressure required to open the preventer and the well pressure under the rams.

A fitting placed in the blowout preventer stack to provide space between preventers for facilitating stripping operations, to permit attachment of choke and kill lines, and for localizing possible erosion by fluid flow to the spool instead of to the more expensive pieces of equipment.

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.

Specialized tools used to run equipment in a well, such as a wireline running tool for installing retrievable gas lift valves. Various tubing-type running tools are also used.

The act of ensuring that a pipe ram preventer will not close on a drill pipe tool joint when the drill stem is stationary. A pup joint is made up in the drill string to lengthen it sufficiently.

The component in a blowout preventer that cuts, or shears, through drill pipe and forms a seal against well pressure. Shear rams are used in floating offshore drilling operations to provide a quick method of moving the rig away from the hole when there is no time to trip the drill stem out of the hole.

A special device placed in a string of tubing that can be operated by a wireline tool to open or close orifices to permit circulation between the tubing and the annulus. It may also be used to open or shut off production from various intervals in a well. Also called circulation sleeve.

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.

To take rams out of a blowout preventer and replace them with rams of a different size or type. When the size of a drill pipe is changed, the size of the pipe rams must be changed to ensure that they seal around the pipe when closed (unless variable-bore pipe rams are in use).

The valve on the choke and flow line that is nearest to the preventer assembly. Its purpose is to stop the flow through the choke and flow line.

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.

A workover performed with a continuous steel tube, normally 3/4 inch to 1 inch outside diameter, which is run into the well in one piece inside the normal tubing. Lengths of the tubing up to 16,000 feet are stored on the surface on a reel in a manner similar to that used for wireline. The unit is rigged up over the wellhead. The tubing is injected through a control head that seals off the tubing and makes a pressure-tight connection. A unique feature of the unit is that it allows continuous circulation while it is being lowered into the hole.

A device run on wireline into the wellbore and inside the fishing string and fish to locate the area where a fish is stuck. When the drill string is pulled and turned, the electromagnetic fields of free pipe and stuck pipe differ. The free-point indicator is able to distinguish these differences, which are registered on a metering device at the surface.

The closing and sealing component on a blowout preventer. One of three types--blind, pipe, or shear--may be installed in several preventers mounted in a stack on top of the wellbore. Blind rams, when closed, form a seal on a hole that has no drill pipe in it; pipe rams, when closed, seal around the pipe; shear rams cut through drill pipe and then form a seal.

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.