Abstract:Based on the standard or specification of the United States PVRC,ASTM,Europe EN and Chinese GB, a seal performance testing device was developed for gaskets used in nuclear power plant.The device is consisted of hydraulic loading system, test element, test medium given system and data acquisition & analysis system,which can evaluate the overall performance of gaskets through measuring the compressibility and recovery,creep performance,stress relaxation,seal ability of gaskets under different temperature, pressure and test medium. The device’s measurement accuracy of load is 10 N, deformation is 1 μm, helium leakage is 1.0×10-11 Pa·m3/s. The device can be used to detect the overall performance of gaskets under room temperature to 450 ℃, which successfully solves the technical problem of seal performance testing of nuclear grade gaskets under elevated temperature.