Abstract: According to the basic structure and technological process of dry gas seal and combined with the actual cases of dry gas seal leakage at the non-driving end of circulating hydrogen compressor, this paper statistically analyzed the trend of the leakage gas flow rate of the main seal at the non-driving end and the change law of the related parameters, and investigated the possible causes of the leakage. Then countermeasures were developed to prolong the service life of dry gas seals in terms of equipment and process. After 10 months of operation, the dry gas seal failed due to leakage, and the device stopped and the failed seal was replaced. Later, the company disassembled the dry gas seal body, analyzed the direct and indirect causes of the failure, and put forward suggestions for rectification

Key words: circulating hydrogen compressor, dry gas seal, leakage