Oil & Gas Glossary 1.0

Chain or rope used to tie down loads of equipment, or the "boomer" used to tighten the chains.

In sucker rod pumping, the difference between the polished rod peak load on the upstroke and the minimum load on the downstroke.

A hydraulic device connected between an engine and a mechanical load such as a compound. Torque converters are characterized by an ability to increase output torque as the load causes a reduction in speed. Torque converters are used on mechanical rigs that have compounds.

To begin to pull on a load.

To lower a load or ease up on a line.

Position of the rig's weight indicator where hook load is zero.

A link and lever mechanism which is used to tighten a chain holding a load on a truck.

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

A method for indicating hook load or force, read off rig's indicator; 1 point = 1,000 pounds

An arbitrarily defined measure of resistance of a material to indentation under static or dynamic load

W = calculated total static load. Also called design factor.

The weight of the drill stem that is suspended from the hook.

An instrument near the driller's position on a drilling rig that shows both the weight of the drill stem that is hanging from the hook (hook load)

A part of the brake mechanism consisting of a flexible steel band lined with a material that grips a drum when tightened. On a drilling rig, the brake band acts on the flanges of the drawworks drum to control the lowering of the traveling block and its load of drill pipe, casing, or tubing.

One of the two valves in a sucker rod pumping system. It moves with the movement of the sucker rod string. On the upstroke, the ball member of the valve is seated, supporting the fluid load. On the downstroke, the ball is unseated, allowing fluid to enter into the production column. Compare standing valve.

A measurement of load safety for wire rope obtained by using the following formula: Safety Factor - B/W where:

A large load-bearing structure, usually of bolted construction. In drilling, the standard derrick has four legs standing at the corners of the substructure and reaching to the crown block. The substructure is an assembly of heavy beams used to elevate the derrick and provide space to install blowout preventers, casingheads, and so forth. Because the standard derrick must be assembled piece by piece, it has largely been replaced by the mast, which can be lowered and raised without disassembly.

A special coupling device inserted one or two joints above the bottom of the casing string that contains a check valve to permit fluid to pass downward but not upward through the casing. The float collar prevents drilling mud from entering the casing while it is being lowered, allowing the casing to float during its descent and thus decreasing the load on the derrick or mat. A float collar also prevents backflow of cement during a cementing operation.