Oil & Gas Glossary 1.0

A sub with a ball seat run on top of a hydraulically set packer to set the packer.

A tool used to open or close a downhole valve; a tool used to set or release a downhole tool, such as a retrievable bridge plug.

A tool employing tripping devices that limit tool movement from pressure either above or below the tool

A rod-like or tube-like extension below a downhole tool, such as a mill, that serves to guide the tool into or over another downhole tool or fish.

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.

A special tool with a rubber packer or lead seal that is used to repair casing. When casing is damaged downhole, a cut is made below the damaged casing, the damaged casing and the casing above it are pulled from the well, and the damaged casing is removed from the casing string. The tool is made up and lowered into the well on the casing until it engages the top of the casing that remains in the well, and a rubber packer or lead seal in the tool forms a seal with the casing that is in the well. The casing-patch tool is an over-shot-like device and is sometimes called a casing overshot.

A retrievable or drillable packer in which sufficient pipe weight is not available to set the tool in compression.

Drill stem test tool; used for formation evaluation.

A tool designed to recover equipment lost in a well.

A finger-like device used to lock or position certain tool components by manipulating the tubing string or downhole tool

A tool used to set drillable or permanent tools, such as packers, retainers, plugs; can be mechanical, electric, or hydraulic.

A generic term, originally a trademark name, used to describe a stage tool, used in selective zone primary cementing.

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).

A heavy-mandrel service squeeze tool with on-off tool used in drilling operations during storm interruptions.

1. a tool for forming an internal screw thread. It consists of a hardened tool-steel male screw grooved longitudinally so as to have cutting edges.

An extension of a retrievable tool, i.e., a retrievable bridge plug, used to set and release the tool.

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.

A specialized fixture on a downhole tool that will allow the tool to be fished out after it's used downhole. See fish.

An accessory to a fishing tool, placed above it. if the tool cannot be disengaged from the fish, the safety joint permits easy disengagement of the string of pipe above the safety joint. Thus, part of the safety joint and the tool attached to the fish remain in the hole and become part of the fish.

A tubular device employed as an isolation tool inside the Christmas tree, to increase the tree's pressure rating during stimulation.

A special nipple made up in the tubing, casing, or drill pipe string the configuration of which is such that a tool contacting it can pass through only if the tool is in the proper position or configuration.

A downhole motor that rotates a bit by the action of the drilling mud on turbine blades b built into the tool. When a turbodrill is used, rotary motion is imparted only at the bit; therefore, it is unnecessary to rotate the drill stem. Although straight holes can be drilled with the tool, it is used most often in directional drilling.

A percussion tool operated mechanically to give an upward thrust to a fish by the sudden release of a tripping device inside the tool. if the fish can e freed by an upward blow, the mechanical jar can be very effective. Also called a hydraulic jar.

A heavy coupling element for drill pipe. It is made of special ahoy steel and has coarse, tapered threads and seating shoulders designed to sustain the weight of the drill stem, withstand the strain of frequent coupling and uncoupling, and provide a leakproof seal. The male section of the joint, or the pin, is attached to one end of a length of drill pipe, and the female section, or box, is attached to the other end. The tool joint may be welded to the end of the pipe, screwed on, or both. A hard-metal facing is often applied in a band around the outside of the tool joint to enable it to resist abrasion from the walls of the borehole.

The tool used in the operation of milling. See mill.

The tool man; a packer hand; a service company hand.

A tool composed of a mandrel on which are mounted several heavy-duty rollers with eccentric roll surfaces. It is used to restore buckled, collapsed, or dented casing in a well to normal diameter and roundness. Made up on tubing or drill pipe and run into the well to the depth of the deformed casing, the tool is rotated slowly, allowing the rollers to contact all sides of the casing and restore it to roughly its original condition.

A hand tool consisting of a handle and chain that resembles the chain on a bicycle. In general, chain tongs are used for turning pipe or fittings of a diameter larger than that which a pipe wrench would fit. The chain is looped and tightened around the pipe or fitting, and the handle is used to turn the tool so that the pipe or fitting can be tightened or loosened.

A compression-set packer

1. the male section of a tool joint.

A tool that goes downhole and is not retrievable.

The female section of a connection. See tool joint.

A trademark for a retrievable squeeze tool.

A tool used to straighten damaged or collapsed casing in a well.

The ability to predetermine where a tool will set or release.

Guiding a downhole tool into the wellbore or up onto the rig floor.

A mechanism in some packers to set and release the tool with a minimum of rotation

A big tool for a small job, used to overcome some excess friction.

The lowering of pipe or tubing into the bore of a downhole tool.

To use a mill to remove the outside area of a permanent downhole tool.

A device to connect the wireline to the tool string.

Running pipe or tubing and landing it on a downhole tool.

The lowest extremity of the tool to which accessories or other tools can be coupled.

The conventional method of formation testing. The basic drill stem test tool consists of a packer or packers, valve or ports that may be opened and closed from the surface, and two or more pressure-recording devices. The tool is lowered on the drill string to the zone to be tested. The packer or packers are set to isolate the zone from the drilling fluid column. The valves or ports are then opened to allow for formation flow while the recorders chart static pressures. A sampling chamber traps dean formation fluids at the end of the test. Analysis of the pressure charts is an important part of formation testing.

A generic term to describe a retrievable service packer.

A fishing tool used to recover a pared string of sucker rods from a well.

A portable cable-tool drilling rig, sometimes mounted on a truck or trailer.

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

A component of a downhole tool, such as a packer, used to wedge slips into the casing wall.

A lead-filled cylindrical device used to ascertain the shape of a fish.

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.

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

N. a tool used to shape, form, or finish other tools or pieces of metal. For example, a threading die is used to cut threads on pipe.

To sharpen, repair, or add accessories to items of equipment (such as drilling bits and tool joints).

To lower pipe or tubing onto a downhole tool, transferring all or part of the hook load.

A generic term used to describe a retrievable service squeeze tool; used in remedial cementing.

2. a tool place in the hole to retain cement or other material; it may later be removed, drilled out, or left permanently.

A device in a rotary table or other tool into which tubing, drill pipe, or slips can be inserted.

A tool used to mill over permanent bridge plugs/cement retainers while retrieving the milled-out debris

A generic term used to describe certain tool movements, such as the cone-to-slip engagement on permanent packers or plugs.

A drillable tool configuration allowing the opening of formation pressure, during drillout, prior to cutting through the tools slips.

A tool that goes inside pipe lost in a well to provide a firm grip and permit recovery of the fish. Sometimes used in place of a spear.

A pinned-end pup joint used to provide additional length and inside diameter necessary to accommodate a standard milling tool.

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

An interval device commonly found in subsurface safety valves used to protect the tool's closure mechanism from the wellbore media.

2. the system of tubulars, packers, and other tools installed beneath the wellhead in the production casing; that is, the tool assembly that provides the hydrocarbon flow path or paths.

A sliding-sleeve ported casing section used in stage cementing.

A retrievable tool used to suspend drilling temporarily during a storm offshore.

Commonly referred to as snubbing; running of tool and/or pulling of tubing under well pressure.

The ability to determine selectively, by the quantity of shear screws or pins, when a tool will set

Blade tool used to scrape away junk or debris from inside casing; run on pipe or tubing.

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

The person (usually a service company employee) in charge of directing fishing operations.

To use a mill on the end of a workstring to remove a permanent tool or fish.

A tool used in drilling to smooth the wall of a well, enlarge the hole to the specified size, help stabilize the bit, straighten the wellbore if kinks or doglegs are encountered, and rill directionally. See ream.

A small hydraulic line used to communicate fluid from the surface to a downhole tool, such as a subsurface safety valve.

One of the natural electrical characteristics exhibited by a formation as measured by a logging tool lowered into the wellbore. Also called self potential or SP.

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.

A percussion tool run on a fishing string to jar downward or upward on a stuck fish to knock it free. The bumper sub body moves up and down on a mandrel.

The string of drill pipe tubing suspended in a well to which is attached a special tool or device that is used to carry out a certain task, as squeeze cementing or fishing.

A fishing tool containing metal-cutting knives that is lowered into the hole and over the outside of a length of pipe to cut it. The severed part of the pipe can then be brought to the surface.

The string of drill pipe or tubing suspended in a well to which is attached a special tool or device that is used to carry out a certain task, such as squeeze cementing or fishing.

See casing-patch tool

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

Terminology used to describe a screen that, when packed off by gels, will give a pressure rise at the surface, thereby "telling" the tool operator that the gel has reached a certain location. Also called tattle-tale.

A downhole tool, composed primarily of slips, a plug mandrel, and a rubber sealing element, that is run and set in casing to isolate a lower zone while an upper section is being tested or cemented.

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.

The supervisor of drilling or workover operations on a rig. Also called a rig manager, rig supervisor, rig superintendent, or tool pusher.

A logging tool assembly, especially the device in the logging assembly that senses and transmits formation data.

A tool set temporarily in the casing or well to prevent the passage of cement, thereby forcing it to follow another designated path. It is used in squeeze cementing and other remedial cementing jobs.

Preliminary test to confirm flow rate through a tool prior to going downhole.

Heavy seamless tubing used to rotate the bit and circulate the drilling fluid. Joints of pipe approximately 30 feet (9 meters) long are coupled together by means of tool joints.

All members in the assembly used for rotary drilling from the swivel to the bit, including the kelly, drill pipe and tool joints, drill collars, stabilizers, and various specialty items. Compare drill string.

All members in the assembly used for rotary cutting from the swivel to the ball, including the kelly, drill pipe and tool joints, drill collars, stabilizers, and various specialty items. Compare drill string.

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.

An essentially full-opening valve installed immediately below the kelly, with outside diameter equal to the tool joint outside diameter.

An essentially full-opening valve installed immediately below the kelly, with outside diameter equal to the tool joint outside diameter.

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.

Trade name for a downhole motor driven by drilling fluid that imparts rotary motion to a drilling bit connected to the tool, thus eliminating the need to turn the entire drill stem to make hole. Used in straight and directional drilling.

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.

A device run on cable-tool drilling line, a service machine, or sand line of a rotary rig to drill up tools, remove downhole debris, and so on.

A fishing tool that is attached to tubing or drill pipe and lowered over the outside wall of pipe or sucker rods lost or stuck in the wellbore. A friction device in the overshot, usually either a basket or as spiral grapple, firmly grips the pipe, allowing the fish to be pulled from the hole.

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.

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.

To obtain cuttings for geological information as formations are penetrated by the bit. The samples are obtained from drilling fluid as it emerges from the wellbore or, in cable-tool drilling, from the bailer. Cuttings are carefully washed until they are free of foreign matter, dried, and labeled to indicate the depth at which they were obtained.

A drilling method in which the hole is drilled by dropping a sharply pointed bit on bottom. The bit is attached to a cable, and the cable is repeatedly dropped as the hole is drilled.

1. a scraping tool that is forced through a pipeline or flow line to clean out accumulations of wax, scale, and debris from the walls of the pipe. It travels with the flow of product in the line, cleaning the pipe walls by means of blades or brushes affixed to it. Also called a line scraper or a go-devil.

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.

A block with lead or another relatively soft material on its bottom. It is made up of drill pipe or tubing at the surface, run into a well, and set down on the object that has been lost in the well. The block is retrieved and the impression is examined. The impression is a mirror image of the top of the fish and indicates the fish's position in the hole, i.e., whether it is centered or off to one side. From this information, the correct fishing tool can be selected.

The column, or string, of drill pipe with attached tool joints that transmits fluid and rotational power from the kelly to the drill collars and bit. Often, especially in the oil patch, the term is loosely applied to both drill pipe and drill collars. Compare drill stem.

The column, or string, of drill pipe with attached tool joints that transmits fluid and rotational power form the kelly to the drill collars and bit. Often, especially in the oil patch, the term is loosely applied to both drill pipe and drill collars. Compare drill stem.

A cast-iron or magnesium drillable tool consisting of a packing assembly and a back-pressure valve. It is used to close off the annular space between tubing or drill pipe and casing to allow the placement of cement or fluid through the tubing or drill pipe at any predetermined point behind the casing or liner, around the shoe, or into the open hole around the shoe.

A downhole tool with rough, sharp, extremely hard cutting surfaces for removing metal by grinding or cutting. Mills are run on drill pipe or tubing to grind up debris in the hole, remove stuck portions of drill stem or sections of casing for sidetracking, and ream out tight spots in the casing. They are also called junk mills, reaming mills, and so forth, depending on what use they have.

A fishing tool used to retrieve pipe lost in a well. The spear is lowered down the hole and into the lost pipe. When weight, torque, or both are applied to the string to which the spear is attached, the slips in the spear expand and tightly grip the inside of the wall of the lost pipe. Then the string, spear, and lost pipe are pulled to the surface.

A type of gravel pack where the wells production packer is removed and a service packer is run in with the gravel pack assembly. After packing, the service tool is retrieved and the production packer rerun.

A large, hook-shaped device from which the swivel is suspended. It is designed to carry maximum loads ranging from 100 to 650 tons (90 to 590 tonnes) and turns on bearings in its supporting housing. A strong spring within the assembly cushions the weight of a stand (90 feet, about 27 meters) of drill pipe, thus permitting the pipe to be made up and broken out with less damage to the tool join threads. Smaller hooks without the spring are used for handling tubing and sucker rods. See stand and swivel.

N: a collar or coupling of tool steel, threaded internally, that can be used to retrieve pipe from the well on fishing jobs; the female counterpart of a taper tap. The die collar is made up on the drill pipe and lowered into the hole until it contacts the lost pipe. If the lost pipe is stuck so that it cannot rotate, rotation of the die collar on top of the pipe cuts threads on the outside of the pipe, providing a firm attachment. The pipe is then retrieved from the hole. Compare taper tap. It is not often used because it is difficult to release it from the fish should it become necessary.

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 Y-shaped chain used to spin up (tighten) one joint of drill pipe into another. One end of the chain is attached to the tongs, another end to the spinning cathead, and the third end left free. The free end is wrapped around the tool joint, and the cathead pulls the chain off the joint, causing the joint to spin rapidly and tighten up. After the free end of the chain is pulled off the joint, the tongs are secured in the spot vacated by the chain and continued pull on the chain (and thus on the tongs) by the cathead makes up the joint to final tightness.