A hinged closure mechanism operating in a pivot manner, used to shut off tubing flow.

1.

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

2.

An indicator of wind direction used during drilling or workover operations where hydrogen sulfide (sour) gas may be encountered.

3.

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.

See floating offshore drilling rig.

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 premature thickening or setting of cement slurry, which makes it unpumpable.

A long flat-bed semi-trailer.

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.

1.

A fluid that has been passed through a filter.

2.

The liquid portion of drilling mud that is forced into porous and permeable formations next to the borehole.

The process of filtering a fluid.

A break in subsurface strata.

Often strata on one side of the fault line have been displaced (upward, downward, or laterally) relative to their original positions.

In drilling, the entrance of formation fluids into the wellbore because hydrostatic pressure is less than formation pressure.

An installation designed for one or more specific and limited extraction units, scrubbers, absorbers, drip points, conventional single or multiple stage separation units, ltx low temperature separators, and other types of separation and recovery equipment.

The procedure of recovering lost or stuck equipment in the wellbore.

See fish.

1.

To recover from a well any equipment left there during drilling operations, such as a lost bit or drill collar or part of the drill string.

2.

To remove from an older well certain pieces of equipment (such as packers, liners, or screen liner) to allow reconditioning of the well.

Porous unsized paper for filtering liquids.

Api filtration test specifies one thickness of 9-cm filter paper whatman no.

50, s & s no.

576, or equivalent.