APPARATUS AND METHOD FOR SNUBBING TUBING-CONVEYED PERFORATING GUNS IN AND OUT OF A WELL BORE

摘要

An apparatus and method for snubbing tubing-conveyed perforating guns in and out of a well bore. The apparatus includes a string of perforating guns wherein adjacent perforating guns are attached using a connector having an upper mandrel which is attached to a lower mandrel by left-hand threaded connection. A ratchet positioned on the upper mandrel allows left-hand rotation of the upper mandrel and ratchet with respect to the lower mandrel while preventing right-hand rotation of the ratchet with respect to the lower mandrel. Shear screws interconnecting the upper mandrel and the ratchet may be sheared upon application of a predetermined torque to allow right-hand rotation of the upper mandrel with respect to the ratchet. The lower mandrel has a recess or reduced diameter portion which is adapted for sealing engagement by a pipe ram in a blowout preventer. The connector allows snubbing of a tubing-conveyed perforating gun string in and out of a well bore under pressure while utilizing existing and unmodified workover equipment and methods of snubbing the guns into the well bore and retrieving them are disclosed.