دیکشنری تخصصی مهندسی نفت - نسخه آنلاین

n: a device placed in the drill or work string that catches debris when a drillable object is being milled or drilled downhole.

n: Theuseful life of a coiled tubing work string is limited due to fatigue damage. This damage is caused by the repeated bending and straightening of the coiled tubing at the gooseneck and reel. The resulting failure mechanism is referred to an low cycle fat

n: a workover performed with a small-diameter tubing work string inside the normal tubing. Equipment needed is essentially the same as that for a conventional workover except that it is smaller and lighter.

n: a type of mechanical jar in which a fluid moving through a small opening slows the piston stroke while the crew stretches the work string. After the hydraulic delay, a release mechanism in the jar trips to allow a mandrel to spring up and deliver a sharp blow. Compare mechanical jar, rotary jar.

n: a tool that is shocking while drilling ,its mainly used to jam release.

n: joints of small-diameter pipe attached to the drill assembly and used to bore a pilot hole when laying pipe. After the route has been established, the pilot string is replaced by the work string.

a plug run on a work string that is being snubbed into a well that can be pumped out when the tubing is landed.

n: a type of mechanical jar whose jarring force is actuated and determined by rotating the work string;the more torque, the harder the jar. See mechanical jar.

n: see work string.

n: 1. in drilling, the string of drill pipe or tubing suspended in a well to which is attached a special tool or device that is used to carry out a certain task, such as squeeze cementing or fishing. 2. in pipe- line construction, the string of washpipe that replaces the pilot string in a directionally drilled river crossing. The work string remains in place under the river until the actual pipeline is made up and is ready to be pulled back across the river.

The drill pipe or tubing string with special tool ,which can fishing, snubbing cementing,etc.






a special, often large string of tubulars that are used during the completion of the well. Usually higher pressure capacity or allow higher weights than the production tubing.

n: see work string.