Surge chamber assembly and method for perforating in dynamic underbalanced conditions

摘要

A surge chamber assembly ( 70 ) for use in a wellbore includes a housing ( 80 ) having one or more openings ( 112 ), a surge chamber ( 100 ) and a combustion chamber ( 98 ). The openings ( 112 ) provide fluid communication between the exterior ( 82 ) of the housing ( 80 ) and the surge chamber ( 100 ). A sleeve ( 114 ) is slidably positioned within the housing ( 80 ) and has a first position wherein fluid communication through the openings ( 112 ) is prevented and a second position wherein fluid communication through the openings ( 112 ) is allowed. A combustible element ( 124 ) is positioned in the combustion chamber ( 98 ) such that combusting the combustible element ( 124 ) generates pressure in the combustion chamber ( 98 ) that actuates the sleeve ( 114 ) from the first position to the second position.