EOFH Extreme Overbalanced Firing Head

The extreme overbalanced firing head (EOFH-BA) is a direct pressureactivated firing head for use on all tubing-conveyed perforating (TCP) gun systems. The EOFH-BA firing head is applied mainly in extreme overbalanced perforating operations in which it is undesirable to shut down the pumping of fluid or gas to wait for the TCP guns to fire.

The firing head is designed for no-delay firing and functions when direct pressure applied across the operating piston exceeds the predetermined value of the shear pins. This pressure drives the operating piston upward. The operating piston, attached to the sleeve, retains the balls that lock the firing pin in place. At the instant the operating piston moves up, the firing pin is freed and driven into the detonator by hydrostatic pressure.

Resources