Perforating apparatus

Claim 1

A PERFORATING GUN COMPRISING A FISHING HEAD, A CABLE HAVING AT LEAST ONE INSULATED CONDUCTOR FOR SUSPENDING SAID FISHING HEAD IN A BOREHOLE, AN OPERATING SUB ASSEMBLY SUSPENDED FROM SAID FISHING HEAD, A TUBULAR SHELL PROVIDED WITH AT LEAST ONE APERTURE SUSPENDED FROM SAID OPERATING SUB ASSEMBLY, AT LEAST ONE CARTRIDGE CONTAINING A CHARGE OF JET FORMING, SHAPED EXPLOSIVE MATERIAL PIVOTALLY MOUNTED IN SAID SHELL ADJACENT SAID APERTURE, MEANS BIASING SAID CARTRIDGE TO A POSITION WHEREIN IT PROJECTS THROUGH SAID APERTURE, MEANS CONTROLLED FROM THE EARTH''S SURFACE FOR RELEASABLY RESTRAINING SAID CARTRIDGE WITHIN SAID SHELL AGAINST SAID BIAS, MEANS MAINTAINED OUT OF EFFECTIVE CONTACT WITH THE EXPLOSIVE CHARGE UNTIL THE LATTER HAS BEEN PIVOTED TO ITS PROJECTING POSITION FOR DETONATING SAID CHARGE, AT LEAST ONE HYDRAULICALLY OPERABLE PISTON WITHIN A CHAMBER IN SAID OPERATING SUB ASSEMBLY CONNECTED TO SAID RESTRAINING MEANS, AND VALVE MEANS CONTROLLED OVER SAID CONDUCTOR FROM THE EARTH''S SURFACE FOR CAUSING WELL FLUID UNDER PRESSURE TO BE ADMITTED TO SAID CHAMBER TO MOVE SAID PISTON TO OPERATE SAID MEANS FOR RELEASABLY RESTRAINING SAID CARTRIDGE WHEREBY THE CARTRIDGE IS RELEASED FROM SAID RESTRAINING MEANS.