Transducer for ultrasonic flow meter
An ultrasonic transducer suitable for use in ultrasonic metering of fluids at extreme temperatures. The ultrasonic transducer includes a piezoelectric crystal, low-density epoxy encasing the piezoelectric crystal, and a cylindrical reinforcing sleeve embedded in the low-density epoxy. The sleeve includes fiber mesh, and surrounds the piezoelectric crystal.
1. An ultrasonic flow meter, comprising:
a central passage for flow of a fluid stream to be metered;
a plurality of pairs of ultrasonic transducers, each pair of transducers configured to form a chordal path across the passage between the transducers, each of the transducers comprising:
a piezoelectric crystal;
low-density epoxy, comprising glass bubbles, encasing the piezoelectric crystal; and
a cylindrical reinforcing sleeve embedded in the low-density epoxy, the sleeve comprising fiber mesh, and surrounding the piezoelectric crystal.
2. The ultrasonic flow meter of claim 1 , wherein the low-density epoxy is formulated to acoustically match the piezoelectric crystal to the fluid stream.
3. The ultrasonic flow meter of claim 1 , wherein the sleeve comprises interwoven glass fibers.
4. The ultrasonic flow meter of claim 1 , wherein the sleeve comprises a woven fiberglass shell.
5. The ultrasonic flow meter of claim 1 , wherein the sleeve comprises at least one of glass, carbon and poly-para-phenylene terephthalamide fibers.
6. The ultrasonic flow meter of claim 1 , wherein the sleeve comprises a longitudinal ridge forming a channel for a conductor that electrically connects the piezoelectric crystal to a transducer driver.
7. The ultrasonic flow meter of claim 1 , wherein the sleeve enables the transducers to operate without cracking at temperatures as low as −50 degrees Celsius.
8. An ultrasonic transducer for use in an ultrasonic flow meter, the transducer comprising:
a piezoelectric crystal;
low-density epoxy, comprising glass bubbles, encasing the piezoelectric crystal; and
a cylindrical reinforcing sleeve embedded in the low-density epoxy, the sleeve comprising fiber mesh, and surrounding the piezoelectric crystal.
9. The ultrasonic transducer of claim 8 , comprising a cylindrical rigid outer housing surrounding the low-density epoxy.
10. The ultrasonic transducer of claim 8 , wherein the low-density epoxy is formulated to acoustically match the piezoelectric crystal to the fluid stream.
11. The ultrasonic transducer of claim 8 , wherein the sleeve comprises interwoven glass fibers.
12. The ultrasonic transducer of claim 8 , wherein the sleeve comprises a woven fiberglass shell.
13. The ultrasonic transducer of claim 8 , wherein the sleeve comprises at least one of glass, carbon and poly-para-phenylene terephthalamide fibers.
14. The ultrasonic transducer of claim 8 , wherein the sleeve comprises a longitudinal ridge forming a channel for a conductor that electrically connects the piezoelectric crystal to a transducer driver.
15. The ultrasonic transducer of claim 8 , wherein the sleeve enables the transducer to operate without cracking at temperatures as low as −50 degrees Celsius.
16. An ultrasonic transducer, comprising:
an electrical/acoustical transducer;
low-density epoxy encasing the electrical/acoustical transducer, the low-density epoxy impregnated with glass bubbles; and
a braided fiberglass reinforcing sleeve embedded in the low-density epoxy and surrounding the electrical/acoustical transducer.
17. The ultrasonic transducer of claim 16 , further comprising a cylindrical rigid outer housing surrounding the low-density epoxy.
18. The ultrasonic transducer of claim 16 , wherein the sleeve comprises a longitudinal ridge forming a channel for a conductor that electrically connects the electrical/acoustical transducer to a transducer driver.