摘要 |
<p>A transfer unit is sealingly connected to a pressure tight housing. The pressure tight housing includes a detonator and electronics circuits connected to the detonator, the pressure tight housing being adapted to be disposed in a well apparatus situated in a wellbore. The wellbore contains fluids at high temperature and pressure, and the pressure tight housing protects the detonator and electronics from the severe temperature and pressure of the wellbore fluids. The transfer unit receives, on one end, the detonator and, on the other end, a separate detonating cord which is adapted to be connected to another separate explosive device and includes a pressure proof housing and a matrix of secondary explosive disposed in a compressed condition within the pressure proof housing between the detonator and the detonating cord, the matrix of secondary explosive functioning like a transversely disposed bulkhead or barrier for protecting the detonator and associated electronics from the severe temperature and pressure of the wellbore fluids which exists adjacent the detonating cord. <IMAGE></p> |