Check valve
Check valve
(OP)
Dear Friends,
I have design one check valve for 10000 PSI .
it is really going good at high pressure. but it is failed at low pressure seat test.
I have used high compressive spring also for giving force towards to seat but still it is not working.
Any one have idea that what is going inside the valve and what should be taken care.
I have design one check valve for 10000 PSI .
it is really going good at high pressure. but it is failed at low pressure seat test.
I have used high compressive spring also for giving force towards to seat but still it is not working.
Any one have idea that what is going inside the valve and what should be taken care.





RE: Check valve
RE: Check valve
In my above question ,
I said . it is working well at high pressure. only fail at low pressure seat test.
On my view , it should be work. but i can not judge that it is working well on high pressure & do not work on low pressure. so what is the possibility for failing at lower pressure.
I assume that when low pressure will also cover the seat's upper surface. seat bottom surface will be sealed with opposite sealing part.
RE: Check valve
what is your definition of fail? In number please and wrt let say ISO 5208 in terms of leakage rate.
Also what type is it? Nozzle or piston/ball type check valve?
check the sealing contact between the "plug" and seat with blue pigment or something.
if you apply high compression spring then it might be possible the cracking pressure when valve required to be open then it will not open. so it is a trade off.
in general yes, high pressure testing normally work tighter compare to low pressure test for Check valve.
if required to work perfectly (zero bubble) for both occasion, maybe you should alter the design.
Kind regards,
MR
https://nosuchvalve.com
All valves will last for years, except the ones that were poorly manufactured; are still wrongly operated and or were wrongly selected
http://www.eng-tips.com/faqs.cfm?&rat1=2&f...
RE: Check valve
RE: Check valve
RE: Check valve
Great thanks for your valuable replies.really countable
RE: Check valve
Petrotrim Services, LLC
www.petrotrim.com
RE: Check valve
The problem is to work both at 10000psi and low pressure. From my understanding the gas pressure assists the spring to create the seal force. Therefore, 10000psi creates enough brute force to seal (probably metal to metal seal) but when the pressure is low the part of the gas pressure force is 50 times smaller. Therefore, it can not seal. Your PEEK seal works as long as the pressure is 200 psi. Go and see what will happen if you put 10000psi.
RE: Check valve
Agree with your comments. yes. Peek seal will not work at high pressure. Metal to metal seal should be.
I am working on check valve which is spring loaded and metal to metal seal. i am modifying some parts . now it is good to prevent on leakage at high pressure & little on low pressure side. now i m facing low seat pressure below 30 PSI only.
Thx to all other frds also who are guiding me .
RE: Check valve
RE: Check valve
other than the max pressure (10,000 psi) and min pressure (30 psi) we know nothing about your valve - drawings, size, type, sealing surfaces, tests being undertaken, leakage requirement, fluid used etc)
It is therefore very difficult to provide any advice or comment on something we can't see other than general comments.
To design something like a check valve with such a large pressure range (330:1) is expecting an awful lot. Check valves are rarely expected to seal completely and with nothing other than reverse pressure difference, there is not much you can do.
Any soft seat will be crushed at the high pressure and therefore you may just need to document what the leakage is at a low pressure.
If you supply more details we might be able to see if there is anything else to comment on...
Remember - More details = better answers
Also: If you get a response it's polite to respond to it.
RE: Check valve
I have read all this and I still don't get it.
Why are you trying to Design your own Check Valve?
What kind of system will this Check Valve be used in?
What kind of Pump (Centrifugal or Reciprocating) will you have upstream of this Check Valve?
What is the Commodity (and state) in this Check valve?
Sometimes its possible to do all the right things and still get bad results
RE: Check valve
Your problem may not be with the design, could be machining problem, material choice or even the calculations may be incorrect.
If you provided a drawing or assy drawing, I'm sure you would receive better feedback.
Petrotrim Services, LLC
www.petrotrim.com
RE: Check valve
Thx for giving your valuable comments.
Dear JBECKHOU, i m not sure PEEK seal will work at high pressure. it will be gone after few months of use of check valve.
I have attached figure here. almost all thing improve.but i could not judge that how can prevent the leakage at low pressure. leakage is between 0 to 30psi now.
it is one inch , custom made valve.