Visualization of tests on globe-type valves using phased array sequence scanning
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 globe valve being tested. For a sequential operation of the globe 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 globe valve to determine if the globe valve is operating properly. By comparing the signals received with a known standard for that globe valve, proper operation, or lack thereof, of the globe valve under test can be determined. Separation of the valve stem from the globe can also be measured.
1. A method of testing a globe valve having a body, valve stem, globe, bonnet, cap and flow passage in the body, turning of said valve stem by rotary motion moves said globe up or down, in or out of contact with a valve seat in said flow passage, the improvement comprising the following steps:
(a) first attaching stem probe to said valve stem above said bonnet and cap;
(b) sending a first signal from a phase array acquisition control to a first multiplexer to generate first parallel signals;
(c) feeding said first parallel signals to a first pulser with delays to generate first phased pulse signals;
(d) first connecting said first phase pulse signals to said stem probe to generate a first wave front in said valve stem;
(e) first receiving a first reflected wave front in said valve stem by said stem probe;
(f) converting said first reflected wave front in a second multiplexer to first reflected energy pulses;
(g) changing said first reflected energy pulses into first delayed energy pulses in a first receiver with delays;
(h) suming said first delayed energy pulses in a first summer to get a first reflected sum;
(i) measuring said first reflected sum to determine first time between end of valve stem and end of gap within said globe signals in said first reflected sum;
(j) multiplying said first time by speed of travel to determine first distance between (1) said end of valve stem and (2) said end of gap within said globe; and
(k) comparing said first distance with standard signals to determine if said globe valve is in danger of failing.
2. The method of testing a globe valve as recited in claim 1 wherein said globe has some lateral movement with support to said valve as said globe valve is closed.
3. The method of testing a globe valve as recited in claim 2 wherein said valve stem is connected to said globe by a threaded nut screwing into said globe and pressing against an end flange of said valve stem.
4. The method of testing a globe valve as recited in claim 3 wherein said valve stem has seals therearound to prevent leakage.
5. The method of testing a globe valve as recited in claim 1 including the further step of:
(l) attaching a body probe to said body;
(m) switching from said stem probe to said body probe;
(n) repeating steps (b) and (c)
(o) second connecting said first phase pulse signals to said body probe to generate said first wave front in said body;
(p) second receiving of said first reflected wave front in said body probe;
(q) repeating steps (f) through (h)
(r) determine second time between said first phased pulse signals and said first reflected wave front; and
(a) second multiplying said second time by speed of travel to give position of said globe.
6. The method of testing a globe valve recited in claim 5 including the further step of visually indicating said position of said probe with visualization software.
7. A method of determining position of a globe in a globe valve having a body, valve stem, bonnet, cap and flow passage in the body, turning of said valve stem by rotary motion moves said globe up and down above a valve seat in said flow passage, the improvement comprising the following steps:
(a) first attaching a body probe to said valve body generally below said globe;
(b) sending a signal from a phased array acquisition control to a multiplexer to generate parallel signals;
(c) feeding said parallel signals to a pulser with delays to generate first phased pulse signals;
(d) connecting said phased pulse signals to said body probe to generate a wave front directly toward said globe;
(d) Receiving by said body probe a reflected wave front off said probe;
(e) converting said reflective wave front in said multiplexer to reflected energy pulses;
(f) changing said reflected energy pulses into delayed energy pulses in a receiver with delays;
(g) summing said delayed energy pulses in a summer to give a reflective sum;
(h) measuring said reflective sum to determine time between said pulse signals and said reflective wave front;
(i) multiplying said time by speed of travel to give position of said globe.
8. A method of determining position of a globe in a globe valve as recited in claim 7 includes a further step of preparing said reflected wave front with standard signals for said globe valve to determine proper operation of said globe valve.