Page 508 - Practical Well Planning and Drilling Manual

Appendix NEW! revised 11/00/bc 1/30/01 3:30 PM Page 484

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Glossary

Keyseat Wiper. A short joint on which are fixed either spiral or
straight blades that are approximately Ω” larger in diameter than the
largest drill collar in the string and is attached to the top drill collar.
The wiper can be rotated or jarred through a keyseat, enlarging it suf-
ficiently to allow the passage of the drill collars.

Keyseat or Key Seat. That section of a hole, usually of abnormal
deviation and relatively soft formation, which has been eroded or
worn by drill pipe to a size smaller than the tool joints or collars.
This keyhole type configuration will not allow these members to pass
when pulling out of the hole. A keyseat can also be worn in a casing
shoe if the shoe depth coincides with a dogleg.

Kill Line. A line connected to the annulus below a blowout preven-
ter for the purpose of pumping into the annulus while the preventers
are closed.

Killing a Well. Bringing a well under control that is blowing out.
Also the procedure of circulating water and mud into a completed
well before starting well-service operations.

Knowledge Box. A cupboard or desk in which the driller keeps the
various records pertaining to drilling operations.

Laminar Flow. Fluid elements flowing along fixed streamlines which
are parallel to the walls of the channel of flow. In laminar flow, the
fluid moves in plates or sections with a differential velocity across the
front which varies from zero at the wall to a maximum toward the
center of flow. Laminar flow is the first stage of flow in a Newtonian
fluid; it is the second stage in a Bingham plastic fluid. This type of
motion is also called parallel, streamline, or viscous flow. See also
Plug Flow and Turbulent Flow.

Lead Tong. A pipe tong suspended in the derrick, normally on the left
of the driller, used when coming out of the hole to break the connec-
tion operated through wireline tied to breakout cathead. In this opera-
tion it is on pin end of joint to be broken. During makeup when going
in the hole it is used on lower or box end as backup to makeup tong.

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