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.
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.
Click on image for an larger view
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.
For well bores in excess of 40 degrees deviation a special
roller fitted drop bar is required.