Structure and Application

Consisting of top sub, spring, bowl, retaining seat, slip, control key, seal ring, seal seat, guide and so on. The upper end of top sub is connected with other tools and drill tool. The lower end of top sub is connected with bowl equipped with spring in the interior. There are three control keys uniformly distributed in the inner wall of the upper end of bowl. the control keys are used to control the position of retaining seat. Three keys are inserted separately in three grooves in the tapered interior section of lower end in bowl where three keys are used to transmit torque. The tapered interior section produces a pinch force against the slip to trigger the fishing operation. The inclined angle among three control keys play an important role in retaining conformance of the slip with the bowl to ensure that the tools can be released easily from the fish.

The retaining seat is installed at the upper end of the external bowl where the three keys are placed. The retaining seat not only can slide axially, but also rotates round the axial line moving with the slip which is installed in the internal circular recess.

Specifications - Table 2 Releasing and Reversing Overshot connection RH