Visualization of tests on swing type check valve using phased array sequence scanning
Computers with proper programs generate signals in phased array sequence. In pulsers with delays, signals are fed through a multiplexor into multiple water wedges that are attached to a valve being tested. For a sequential operation of the valves from the open to the closed position, ultrasonic signals are transmitted through 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 valve to determine if the valve is operating properly. By using multiple water wedges and pass visualization software, the operator can see exactly how the valve is functioning, which information can be stored for inspections or maintenance.
1. 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.
2. The method of testing a check valve while in use as recited in claim 1 wherein said generating step is via a first multiplexer and a pulser with first delays.
3. The method of testing a check valve while in use as recited in claim 2 wherein said receiving step is via a second multiplexer and a receiver with second delays.
4. The method of testing a check valve while in use as recited in claim 3 wherein said first displaying or said second displaying is through software to provide a visual indication as to the operation of said check valve.