Patent ID: 8347963
Filing Date: 2013-01-08
Classification: E21B,F42B,F42D

Abstract:
1. A method of perforating a well, comprising: selecting a desired transient underbalanced condition; configuring a perforating gun string to include a sealed internal chamber having a chamber pressure with charges positioned therein to achieve the transient underbalanced condition; deploying the perforating gun in a wellbore having a wellbore pressure greater than the chamber pressure; and firing the perforating gun to detonate the charges; forming perforating ports in the perforating gun as a result of the detonation of the charges to allow for fluid access to the sealed internal chamber from the wellbore; and heating gas within the sealed internal chamber as a result of the detonation of the charges so that the chamber pressure remains less than the wellbore pressure so that wellbore fluid passes through the perforating ports from the wellbore to achieve the transient underbalanced condition.