The profile was designed 20 years ago by my colleagues but with experimental tests and I am not sure if the chevron pack works correctly. The lower angle is 60°, the upper 90° (inner diameter 16mm and outer 25mm). The pack consists of 4 V-elements plus the male and female on one side of the...
Hello, everyone. I am testing a valve in which a PTFE chevron-type sealing system is used on a sliding stem. Is there any way of calculating even indicatively the necessary compressive force to be applied to the seals? If I increase or decrease the number of elements (e.g. from 4 to 5 or vice...
It is a pneumatic valve (like Y valve), according to PED directive (I used EN 12516-2 and EN 12516-4).
A new customer need the CRN number and I'd like to verify thickness with ASME standard.
Hello everyone. I dimensioned a forged brass valve according to EN standard. Now i need to prove the correct design according to ASME standard.
I know that for ferrous material there is B16.34 but what about brass valve?
Can someone tell me which standard i need?
Thank you
Many regulation like EN 12516-4 or EN 15776 indicate as low temperature limit for GJS 400-15 or GJS 450-10 -10°C. Many manufacturers of butterfly and gates valves indicate as low temperature limit -20°C. In Europe there is PED (pressure equipment directive) and use of material below the...
Hello,
I have a simple question.
I know that many valves (gate, butterfly...) are casted in spheroidal graphite GJS 400-15 that is limited to -10°C but in the data sheet and PED certificate are marked up to -20°C. How is it possible?
Thank you for your reply.
I think that all competitors try to declare a higher value than the real one. We had a test bench used to test small valves (up to 1"1/2) and CVs obtained in the test are +/- 4% CVs obtained in CFD analysis.
The problem is that competitors values are nearly twice as much.
Hello every one. I have a problem with flow coefficient of ball and butterfly valve.
I tried to calculate flow coefficient of some butterfly valves according to IEC and simulating the scheme indicated. All values obtained with CFD are very close to real values but other competitors declare...
Hi, I'm from Italy and I have a question about EN 593.
At point 4.2.3.1 of EN 593 it's indicated the maximum flow velocity of fluid in a butterfly valve. In the column of gaseos fluid there is the indication (at 1 bar). My question is: is the velocity limit indicated the limit of gaseos fluid at...
