Frederick, Thanks for your post. You've convinced me to cryo-treat this rotating assembly.
Now I'm wondering how much stock I should leave on the "roughed out" part. I'm thinking about .020 - .030 on diameter (I don't want leave too much stock on it causing me to loose some of the...
fang54,
I've read this paper a dozen times. It's a great reference! What I'm looking for is the same level of detail with non-metallics other than the ones covered in the NIST paper. The nist paper covers, polyamide, teflon, and G-10. The most suitable material among those three is G-10...
Hi All,
What do you know of Cryogenic Processing? I came across this link...
http://www.johnsonpackings.com/cryo/cryo.htm
I called them up and asked about the process. They soak the parts at LN2 temps for a number of hours, then temper the parts in the oven and repeat a few times.
I have...
iainuts,
I was thinking of using G-10 NT from Spaulding Composites, so it's good to hear that I'm on the right track.
As far as #3 goes... I need to hold a helium tight seal with an o-ring touching the G-10. Spaulding says that they can get the surface finish down to 40 RMA, so with...
Hi,
What non metallic material is best based on the following (in order of importance):
1) Has a CTE as close as possible to stainless
2) Relative isentropic contraction properties
3) Hold a piston/bore O-ring seal with stainless separating vacuum space from helium space (140 psia and 200...
Hi, Can anyone recommend a Thermal Analysis Shop that's worth their weight? I'm looking for a company who is certified enough to give some sort of guarantee to their results? I want this firm to run a full cfd/thermal analysis on a cryogenic pump design. There's alot of them out there, just...
By the way, I leared a few things about PCTFE. The extruded stuff creeps quite a bit while the compression molded stuff does not.
After talking with someone at PBY plastics, they said it has something to do with crystalinity. The more slowly they cool it down, the more crystaline it becomes...
Any recommendations on suppliers of cryogenic globe or gate valves?
Service Tube: 1" with .065 wall
Service Fluid: Helium
Service Temp: 70 K
Service Pressure: 300 psi
Service Flow: 15 g/s
Can anyone add advice on the following topic?
I'm considering braising a titanium shroud to a titanium impeller using silver based braise compound. When choosing the best solder alloy for the job, what should I consider? CTE? Ductility? Interfacial Chemical Bonding Strength?
The diameter...
I'm designing a rig to test a circulation fan. The system is closed loop with Helium as the working fluid at temp 50K and pressure 100 psi.
I need to measure flow, temp and pressure near and upstream of the fan and measure pressure near and downstream of the fan. Consideration needs to be...
