Rupture strength of a pressurized separator

Complex investigations of the strength of an oil separator were performed to establish causes of its sudden failure. While under constant monitoring by the method of acoustic emission and ultrasound monitoring, the separator fitted with an extensometer was subjected to 100 cycles each under a working pressure of 29 MPa and a computed pressure of 32.5 MPa, and 1000 cycles under a test pressure of 42.5 MPa, and 700 cycles with the pressure increased from 80 to 90 MPa without formation of visible cracks. Failure of the separator occurred with increasing pressure cycling up to 112 MPa. Residual hoop strains after failure did not exceed 3%.