Patent ID: 8904873

Claim:
A method of testing a check valve while in use, said check valve having a bonnet and a valve body, said testing to (a) determine if said check valve is operating properly and (b) to locate an air pocket, if any, in said check valve, said method comprising the following steps: attaching piezoelectric devices to at least two water wedges having a reflective index approximately the same as water; first mounting a first of said water wedges on said bonnet of said check valve; second mounting a second of said water wedges on said valve body so that said second water wedge generally opposes said first water wedge; generating a phased array of phased output pulses; feeding said phased output pulses to multiple channels of said piezoelectric devices attached to said water wedges, said piezoelectric devices having an extra channel; creating from said phased output pulses an acoustical phased wave front to be transmitted by either (a) said first water wedge or (b) said second water wedge; receiving said acoustical phased wave front in the other of (a) said first water wedge or (b) said second water wedge and: (1) if said air pocket is not in said check valve: (a) summing said received acoustical phased wave front to give an output; (b) first displaying said output to visually indicate condition of said check valve during operation, but; (2) if said air pocket exists in said check valve: (a) receiving a reflected signal from said air pocket on said extra channel at the transmitting water wedge; (b) calculating distance to said air pocket by using time of travel of said reflected signal; (c) reversing functions of said first water wedge and said second water wedge and repeating steps (2)(a) and (b); (d) second displaying location of said air pocket in said check valve.