دیکشنری تخصصی مهندسی نفت - نسخه آنلاین

n: an expandable, cylindrically shaped gripping mechanism that is fitted into an overshot to retrieve fish from the borehole. See grapple.

n: a mechanism that is fitted into an overshot to grasp and retrieve fish from the borehole. The interior of a grapple is wickered to engage the fish. See basket grapple. spiral grapple.

n: the part of a catching tool (such as overshot or spear) that engages the fish.

a spring like device, resembling a interlocking finger puzzle that allows a round work piece to slide through the ID when in compression, but grips the work piece (or fish) when a tension load is applied. Common in overshot fishing devices.

n: a fishing tool that is attached to tubing or drill pipe and lowered over the outside wall of pipe or sucker rods lost or stuck in the wellbore. A friction de- vice in the overshot, usually either a basket or a spiral grapple, firmly grips the pipe, allowing the fish to be pulled from the hole.

n: a fishing tool that is attached to the drill pipe and is lowered over the fish and engages externally. An overshot can also be used to recover a wireline survey tool (single shot).

a fishing tool designed to slip over the fish and grasp the outside.

n: a helically shaped gripping mechanism that is fined into an overshot to retrieve fish from the borehole. See grapple.