دیکشنری تخصصی مهندسی نفت - نسخه آنلاین

n: old-style tap with longitudinal grooves across the threads. See tap, taper tap.

n: A usual fishing tool for fishing tubular goods dropping in the wellbore. There are thread and coning in the inner surface.

another name for a tapered tap. Used to screw into boxed of connections.

n: a collar or coupling of tool steel, threaded internally, that can be used to retrieve pipe from the well on fishing jobs;the female counterpart of a taper tap. The die collar is made up on the drill pipe and lowered into the hole until it contacts the lost pipe. If the lost pipe is stuck so that it cannot rotate, rotation of the die collar on top of the pipe cuts threads on the outside of the pipe, providing a firm attachment. The pipe is then retrieved from the hole. It is not often used because it is difficult to re- lease it from the fish should it become necessary. Compare taper tap.

n: See box tap.

n: a tap with a gradually decreasing diameter from the top. It is used to retrieve a hollow fish such as a drill collar and is the male counterpart of a die collar. The taper tap is run into a hollow fish and rotated to cut enough threads to provide a firm grip and permit the fish to be pulled and recovered. See tap. Compare die collar.

a spear-like fishing device with threads to engage ID threaded fish.