A computer with a proper program generates a phased array sequence of signals. In a pulser with delays, the signals are fed through a multiplexor into multiple water wedges that are attached to a lift-type check valve being tested. For a sequential operation of the lift-type check valves from the open to the closed position, ultrasonic signals are transmitted through the fluid contained in the valve and reflected back through piezo-electric crystals to the multiplexor. By summation and merger of the signals, an image can be developed of the operation of the lift-type check valve to determine if the lift-type check valve is operating properly. By comparing the signals received with a known standard for that lift-type check valve, proper operation, or lack thereof, of the lift-type check valve under test can be determined.