Dynamically monitoring a reciprocating poppet valve?
Dynamically monitoring a reciprocating poppet valve?
(OP)
I need to instrument and dynamic monitor reciprocating compressor poppet valve motion. The poppet is mushroom shaped, made of peak material (plastic), operates in an atomosphere => 250 F, and is located internal to a gas compressor operating at 1200 rpm. Compressor valves consists of multiple poppets and it is our task to determine if they all are moving uniformly up and down, or some are floating or not moving at all which would imply too many for the given flow. I have done simular work on steel plate valves using proximitors which will not work with the plastic material. There is a 1 inch long by .385 dia. coil spring inside the stem of the mushroom that aids the return of the poppet to the seat. I am currently looking at monitoring dynamic spring force using comercial load cells with the intent of relating that to distance traveled. Any one ever do a simular project and have good advice on what technique or instrumentation to utilize?





RE: Dynamically monitoring a reciprocating poppet valve?
The obvious problem is, these valves are internal to a compressor. So a camera inside is probably impractical.
But prototype systems can sometimes have a window installed to confirm such one-off design questions. Literally cut away part of the system and replace it with an appropriate 'glass' window.
Or, can you view the back of the valves, the spring side? Might be able to see what's going on from that side.
If you don't get a suitable idea here, then maybe try the automotive forums. Engine designers must have similar desire to track valve motion.
RE: Dynamically monitoring a reciprocating poppet valve?
RE: Dynamically monitoring a reciprocating poppet valve?
RE: Dynamically monitoring a reciprocating poppet valve?
> acoustic distance
> laser distance
> accelerometer directly on the poppet
TTFN
FAQ731-376: Eng-Tips.com Forum Policies
Chinese prisoner wins Nobel Peace Prize
RE: Dynamically monitoring a reciprocating poppet valve?
RE: Dynamically monitoring a reciprocating poppet valve?
RE: Dynamically monitoring a reciprocating poppet valve?
Dan - Owner

http://www.Hi-TecDesigns.com
RE: Dynamically monitoring a reciprocating poppet valve?
Can you make a see thru port out of glass or some other material? It could be an inch thick. Then you would be free to use a high speed camera and actually watch the physical dynamics. This would skip you past all the "if this - then maybe that is happening".
Keith Cress
kcress - http://www.flaminsystems.com