We are having many issues with valves that perform well at ambient but then leak at Cryogenic temperatures. We have done things like:
1. Use heavy spring PTFE jacket seals
2. Achieve surface finish of 4 Ra uin on both the gland ID and gland OD
3. Use Krytox grease
I think the problem is at...
Full hard - strip is rolled to half of the original thickness
Half hard - ?
40% cold reduced - ?
How do you calculate the original thickness for half hard and 40% cold reduced? I thought I could find any definition online but I am not able to.
We have a helium/LOX valve that is leaking even with heavy spring PTFE seals. The valve finish is hard anodized aluminum and even with a 4 Ra finish, leakage is higher than desirable.
Can we apply some type of second coating to reduce this leakage? Something to fill up the deep pores in the...
We have a helium/LOX valve that is leaking even with heavy spring PTFE seals. The valve finish is hard anodized aluminum and even with a 4 Ra finish, leakage is higher than desirable.
Can we apply some type of second coating to reduce this leakage? Something to fill up the deep pores in the...
Anyone familiar with API15 C203601 requirements? We sells spring energized PTFE seals and now our customer is asking us if our seals meet this requirements and we don't know. I can't even find a place to purchase this document. Can anyone help?
I have two spring materials to choose from for use in a spring energized seal but not sure if Elgiloy or Inconel 718 will be better in term of better resistance to corrosion because of the present of H2S at 17% conc.
Could you please give some advice? If possible, please include source of...
Hi,
I have a 12V 8Ah Lead Acid Battery. I bought a 12V charger that was on Sale but I am not sure if they are compatible.
The Charger indicates:
"High Performance Ni-cd Battery Charger"
Input: AC 117V 60 Hz
Output: DC 12V 6W 600mA
Thanks,
Is there a material data library in Abaqus? I need plastic strain data for Steel and PTFE.
I found this steel data from an Abaqus tutorial from a University, could anyone verify that it is correct?
*ELASTIC
210.E09, 0.31
*PLASTIC
200.2E06, 0.0
246.0E06, 0.0235
294.0E06, 0.0474
374.0E06...
Hi all,
I finally got my model of helical spring compression to run.
Initially to keep the model simple, I define only E = 29,000,000 psi and PR = 0.3. The result seems a little high especially at the toward the end with larger compression (see attached graph).
Then I attempted to define...
I need to perform an analysis to estimate the compression force of an O-ring. I know that a non-linear analysis is better but I think 20% compression of an o-ring is not too bad and I just need an approximation of the compression force.
My question is can I use the Flexural Modulus of EPDM as...
Hi,
My model simulates two rigid plates compressing a helical coil spring. However, I don't see the two plates in the result, just a line. However, the result seems to be correct. What is wrong?
My model is setup and ran but I have no clue how to get the right output. Please see that attached image.
I need to get the reaction force and node with highest stress.
Also, this might be a stupid question but what is the difference between History Output Request and Field Output Request...
I have an axissymmetric model with the pressure energizing the cavity of a u-cup seal. However, when I apply the pressure to the cavity of the seal, the pressure direction is pointing in both direction. Is this a problem?
I am new to Valves and need to know about the differences between various valve designs and when to use them. For example, when to use ball valve and when to use needle valve design.
Thanks,
For ball valves, we usually use Spring Energized Teflon seals for the seat position for temperature range under 300C. But now we have an application where the fluid temperature can be 400C to 450C where Teflon will not work, what kind of seal should we use?
thanks,
Hi,
I tried a Bronze filled PTFE bearing/wearring but because the speed is 600 FPM the bearing lasted only 15 minutes. The PTFE basically melted and disappeared leaving only the bronze behind.
What bearing material should I try?
Shaft is 3.5 inch in diameter, bearing cross-section is .100"...
Hi,
I completed an analysis of a U-CUP seal installed into a gland (thus it is compressed by the rod and bore).
But I am self-taught and really weak on the Result and Visualization part so could you please help me find out the Reaction force on the rod?
I have attached the cae file along with...
Hi,
I created a model of a helical spring (5 coils) being compressed a two rigid plates. It didn't converge. Could any one please take a look at the file and show me what is wrong?
Many thanks,
