Patent ID: 7854587
Filing Date: 2010-12-21
Classification: F01D,F04D

Abstract:
1. A multistage centrifugal compressor, comprising a dry gas seal arrangement configured to prevent leakage of working gas from a machine inner side, a secondary dry gas seal arrangement configured to back up the primary dry gas seal arrangement, a seal gas line operatively arranged between the primary and secondary dry gas seal arrangements for introducing the gas leaked from the primary and secondary dry gas seal arrangements, wherein the seal gas line has an orifice and a check valve, and an accumulator is installed in series between the orifice and the check valve, the accumulator being configured and arranged to contain the gas that has back-flowed from the outside to the check valve and to prevent, previous to the check valve being completely closed due to a back-pressure increase, the back-flowed gas contained therein from flowing into the sealing arrangements.