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McMaster pressure rating...

Posted: Wed Jul 07, 2010 3:36 pm
by saefroch
I was looking through McMaster for a 3/8" pipe cross, when I came across this cross, part #4464K313.

It's rated to 150 psi, which seems painfully low to me. I'm also not sure if that part is schedule 10 or schedule 40. I'm planning to make something of a QDV hybrid, so I need something that can take at least a 10x mix, and steel is usually a good bet, but the low pressure rating has me worried a bit. Explanation? I can't even find the wall thickness for this part to estimate what it can take...

Posted: Wed Jul 07, 2010 3:43 pm
by c11man
before you even worry about the cross please tell us how your going to get a hybrid QDV to work!

it is rated to 150psi just like all the stee fittings in your store. to get a higher rating your gonna have to pay more. oh course it can hold more but how much no know knows...

Posted: Wed Jul 07, 2010 3:58 pm
by saefroch
Guess I'll post the diagram in this thread then, just finished it. I'll edit this post when I get it uploaded.

EDIT:
Image

Voila! It should work... at least for low mixes.

Posted: Wed Jul 07, 2010 4:04 pm
by ramses
are the pipes the orings seal against the same diameter? If so, it won't open as you intend. If not, how are you making them different.

you could also try an air spring instead of the coill one.

Posted: Wed Jul 07, 2010 4:06 pm
by saefroch
Please discuss the design here: http://www.spudfiles.com/forums/viewtop ... tml#292692

The title and location are more appropriate.

Posted: Wed Jul 07, 2010 4:08 pm
by Hotwired
Looks like the left hand side of the piston is within a section of pipe inside the fitting which could give the area difference to blow back the piston.

I feel sorry for that front o-ring, it's gonna get toasted :P