Oil & Gas Glossary 1.0

A relatively small container of high explosive that is loaded into a perforating gun. On detonation, the charge releases a small, high-velocity stream of particles (a jet) that penetrates the casing, cement, and formation. See perforating gun.

The oil company in charge of development and production in an oilfield in which several companies have joined to produce the field.

The driller or head well puller in charge of operations on a well servicing rig that is used to pull sucker rods or tubing

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

1. a charge of high explosive, usually nitroglycerine, detonated in a well to shatter the formation and expedite the recovery of oil. Shooting has been almost completely replaced by formation fracturing and acid treatments.

An employee of a drilling contractor who is in charge of the entire drilling crew and the drilling rig. Also called a drilling foreman,, rig manager, rig superintendent, or rig supervisor.

An employee of a drilling contractor who is in charge of the entire drilling crew and the drilling rig. Also called a toolpusher, drilling foreman, rig supervisor, or rig superintendent.

A spool-shaped attachment on a winch around which rope is wound for hoisting and pulling.

The employee directly in charge of a drilling or workover rig and crew. His main duty is operation of the drilling and hoisting equipment, but he is also responsible for downhole condition of the well, operation of downhole tools, and pipe measurements.

Wedge-shaped toothed pieces of metal that fit inside a bowl and are used to support tubing or other pipe.

A formation-stimulation process first used about a hundred years ago in Pennsylvania. Nitroglycerine is placed in a well and exploded to fracture the rock. Sand and gravel or cement is usually placed above the explosive charge to improve the efficiency of the shot. Nitro shooting has been largely replaced by formation fracturing.

A device fitted with shaped charges or bullets that is lowered to the desired depth in a well and fired to create penetrating holes in casing, cement, and formation.

The set of dense rubber, washer-shaped pieces encircling a packer, which are designed to expand against casing or formation face to seal off the annulus.

A helically shaped gripping mechanism that is fitted into an overshot to retrieve fish from the borehole. See grapple.

An expandable, cylindrically shaped gripping mechanism that is fitted into an overshot to retrieve fish from the borehole. See grapple.

A cylindrical ring, usually vise-shaped, employed to back up (or assist) a sealing member against extrusion under temperature and pressure.

A perforating gun that consists of a metallic strip on which encapsulated shaped charges are mounted. After the gun is fire, the strip is retrieved. See gun-perforate.

A device made up in the drill stem and lowered into the well to allow the casing and blowout preventers to b pressure-tested. The sealing device is cup-shaped and is therefore called a cup.

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.

A bell-shaped hole dug beneath a pipeline to provide room for use of tools.

A centrifugal device for removing sand from drilling fluid to prevent abrasion of the pumps. It may be operated mechanically or by a fast-moving stream of fluid inside a special cone-shaped vessel. Compare desilter.

A wheel-shaped wrench that is attached to the sucker rod string at the surface and is manually turned to unscrew the string to allow it to be pulled from the well.

A pin shaped like a carpenter's nail and placed in a pressure relief valve. When the pin shears, it opens the valve to relieve pressure inside a vessel.

A special device that, when fitted in to the master bushing, transmits torque to the kelly and simultaneously permits vertical movement of the kelly to make hole. It may be shaped to fit the rotary opening or have pins for transmitting torque. Also called

A globe valve that contains a sharp, pointed, needle-like plug that is driven into and out of a cone-shaped seat to control accurately a relatively small rate of fluid flow. In a fuel injector, the fuel pressure forces the needle valve off its seat to allow injection.

To pierce the casing wall and cement to provide holes through which formation fluids may enter or to provide holes in the casing so that materials may be introduced into the annulus between the casing and the wall of the borehole. Perforating is accomplished by lowering into the well a perforating gun, or perforator, that fires electrically detonated bullets or shaped charges.

A type of mobile offshore drilling unit that floats and is not secured to the seafloor (except for anchors). Floating units include inland barge rigs, drill ships and ship-shaped barges, and semisubmersibles. See mobile offshore drilling unit.

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.

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.

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.

A floating offshore drilling unit that has pontoons and columns that when flooded cause the unit to submerge in the water to a predetermined depth. Living quarters, storage space, and so forth a reassembled on the deck. Semisubmersible rigs are either self-propelled or towed to a drilling site and either anchored or dynamically positioned over the site, or both. In shallow water, some semisubmersibles can be ballasted to rest on the seabed. Semisubmersibles are more stable than drill ships and ship-shaped barges and are used extensively to drill wildcat wells in rough waters such as the North Sea. Two types of semisubmersible rigs are the bottle-type semisubmersible and the column-stabilized semisubmersible. See floating offshore drilling rig.