In July 2020, with cooperation of the Institute of Underwater Engineering Design of COOEC, Roc-Master has successfully completed the hyperbaric chamber test of the 7 1/16 10000psi API 6A self-sealing test flange at a water depth of 80m, and completed the hydraulic strength test of flange inner cavity according to COOEC’s requirement; Test process was monitored by COOEC’s engineers, relevant test reports have been approved by COOEC. Self-sealing test flange has the advantages of simple structure, convenient operation, test-time saving, cost saving for pressure and gas sealing test. In addition, it can realize the real - time sealing monitoring in the application of flanges, which solves issues like high labor costs, high expense, long test time, difficulty to monitor seal failure during traditional test operation. Since 2016, self-sealing test flanges supplied by Roc-Master have been applied in relevant riser piping system in deep-water subsea projects of MODEC, which operate well and with more orders in process.