Oil & Gas Glossary 1.0

A friction wrench used in repairing oil-well pumps

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 special wrench designed for use in connecting the cage of a sucker rod pump to the sucker rod string.

1. a measure of volume for petroleum products in the United States. One barrel is the equivalent of 42 U.S. gallons or 0.15899 cubic meters (9,702 cubic inches). One cubic meter equals 6.2897 barrels.

2. the cylindrical part of a sucker rod pump in which the piston-like plunger moves up and down. Operating as a piston inside a cylinder, the plunger and barrel create pressure energy to lift well fluids to the surface.

A laboratory unit used for evaluating or testing drilling fluids. One gram of material, when added to 350 milliliters of fluid, is equivalent to 1 pound of material when added to one 42-gal barrel of fluid.

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.

A small mud tank with a capacity of 10 to 15 barrels, usually with 1-barrel or H-barrel divisions, used to ascertain the amount of mud necessary to keep the wellbore full with the exact amount of mud that is displaced by drill pipe. When the bit comes out of the hole, a volume of mud equal to that which the drill pipe occupied while in the hole must be pumped into the hole to replace the pipe. When the bit goes back in the hole, the drill pipe displaces a certain amount of mud, and a trip tank can be used again to keep track of this volume.

Abbreviation: barrel

A container in which various chemicals are mixed prior to addition to drilling fluid.

Large wrench used for turning when making up or breaking out casing. See tongs.

A measure of the volume of gas produced with oil, expressed in cubic feet per barrel of cubic meters per tonne.

A tubular device, usually from 10 to 60 feet (3 to 18 meters) long, run at the bottom of the drill pipe in place of a bit and used to cut a core sample.

Pipe tongs that grip the pipe with a chisel-like insert in the jaw of the wrench.

To pull the drill stem out of the wellbore to change the bit, to change from a core barrel to the bit, to run electric logs, to prepare for a drill stem test, to run casing, and so on. Also called trip out.

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.

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 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.

N: a cylindrical sample taken from a formation for geological analysis. Usually a conventional core barrel is substituted for the bit and procures a sample as it penetrates the formation. v: to obtain a formation sample for analysis.

A sucker rod pump in which the barrel is attached to the tubing. See sucker rod pump.

A special valve installed below the kelly. Usually, the valve is open so that drilling fluid can flow out of the kelly and down the drill stem. It can, however, be manually closed with a special wrench when necessary. In one case, the valve is closed and broken out, still attached to the kelly to prevent drilling mud in the kelly from draining onto the rig floor. In another case, when kick pressure inside the drill stem exists, the drill stem safety valve is close to prevent the pressure from escaping up the drill stem.