Apparatus and method for detonating well perforators

摘要

A pressure-actuated head for detonating a gun for perforating a well bore is suspended on a tubing string for lowering down the well. The head includes a detonator pin biased towards a detonator but restrained until detonation is required. Detonation is effected by causing or allowing a pressure differential to develop across a piston. Fluid communication between chambers on respective sides of the piston is via a pressure control system which allows the pressure differential to develop over a period of time.