دیکشنری تخصصی مهندسی نفت - نسخه آنلاین

. See keyseat. key valve n: see shutoff valve.

n: This schlumberger module provides direct measurements of wellbore fluid resistivity and temperature, also cable tension below the toolstring head. Useful to run in poor hole condition;should allow differentiation of differential sticking and keyseat stic

n: 1. an abrupt change in direction in the wellbore, frequently resulting in the formation of a keyseat. 2. a sharp bend permanently put in an object such as a pipe, wire rope. or a wire rope sling.

n: The elbow caused by a sharp change of direction in the wellbore.

n: a kind of tools assembly in which a rolling cutter reamer

is joined among two or three drill collars and a stabilizer is joined on each end of the drill collar respectively

n: 1. an undergauge channel or groove cut in the side of the bore- hole and parallel to the axis of the hole. A key seat results from the rotation of pipe on a sharp bend in the hole. 2. a groove cut parallel to the axis in a shaft or a pulley bore.

a out of round bore hole worn to the side, often with the side of the drill pipe in a crooked hole, that looks like a key hole. Keyseats create problems with passage of tool joints and larger pipe that does not bend as easily as smaller diameter pipe.

n: a barge in which the mast is placed over a channel cut out of the side of the barge and through which drilling or workover operations are performed.

n: see keyseat wiper.

n: a device used to ream out a hole where keyseating has occurred. Usually a bumper sub is used first to loosen stuck pipe from a sharp bend, and then a keyseat wiper is used to enlarge the hole at the keyseat caused by the pipe. Also called

n: a tool made up in the drill string to ream out any keyseats that may have formed and thus prevent the pipe from becoming struck.

n: The limiting or prevention of motion of the drillstring by anything other than differential pressure sticking. Mechanical sticking can be caused by junk in the hole, wellbore geometry anomalies, cement, keyseats or a buildup of cuttings in the annulus.

n: a section of a borehole in which excessive wall cake has built up, reducing the hole diameter and making it difficult to run the tools in and out. Compare keyseat.

n: The well section that its diameter reducing because mud cake over thick or layer swelling.

a restricted place in the bore hole, caused by wall cake, dog leg, deviation change or other factor.