Purpose
The Brico Mechanical Firing Head is used to initiate the detonation of TCP perforating guns. Simple and economical, the firing head is an effective tool that is safe and easy to operate for TCP operations. Compatible with most existing perforating systems, a proven rugged design, this extremely compact firing head is simple to assemble and easy to field redress.

Operation
The Mechanical Firing Head is activated by means of a drop bar released from surface into the tubing or drill pipe once the operator has reached the required depth and ready to perforate. The drop bar impacts the top of the firing pin, which in turn shears the shear pin, this impact action detonates the explosive initiator. The initiator detonates a booster attached to detonating cord (located in the top gun sub) causing the guns to fire. Always use compatible equipment - use a Brico drop bar to operate this firing head.

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Important: The strike force required to shear the shear pin, impact the firing pin to detonate the initiator should be no less then 15ft.lbs. (2.07 Kgs/m) with velocity of 7ft. (2.14m) per second. It is also good practice to ensure the system is not run dry, 10 meters (30 feet) of fresh water should always be filled into the tubing/ drill pipe above the mechanical firing head system. The Brico Fill/Flow sub or some other type of debris barrier should always be installed 9m (30 feet) above the firing head system.
Special Note: For well bores in excess of 40 degrees deviation a special roller fitted drop bar is required.