5-10k psi + hydraulic fluid + flexible = ? material
5-10k psi + hydraulic fluid + flexible = ? material
(OP)
I am looking for a material that would be used as a diapragm that is expanded by pumping hydraulic fluid into it. Working pressure can be as low as 5k psi, but 10k is more desirable. And, being a diapragm, it needs some flexibility to collapse when it is not pressurized. If I have a starting point I should be able to figure out the specifics from there. Thanks!





RE: 5-10k psi + hydraulic fluid + flexible = ? material
Wikipedia says "The three most common types of hydraulic fluids are mineral oil, organophosphate ester, and polyalphaolefin. Others are based on glycol esters and ethers, castor oil, or silicone"
So, based on that most hydraulic fluids are non polar and so some polar polymer would be a good choice as the diaphragm as it will not get swollen by the fluid. Some suggestions would therefore be nylon or perhaps a dual layer of nylon for the side exposed to the fluid and some other polymer to give the flexibility you want. Silicones and fluoropolymers may work too as they are no non-polar that they don't mix with hydrocarbons like many of the hydraulic fluids.
So to summarise find out what type of hydraulic fluid you will be using and choose the material based on that. Or, if you can choose the fluid type then do it the other way around, i.e. find the polymer with the mechanics you want at www.matweb.com and then find the type of hydraulic fluid that is compatible with it (i.e. test to see if the polymer is swollen on exposure to the fluid).
Also a Google search for "hydraulic seal" gave me tons of hits on what materials are used for such applications. E.g. http://
RE: 5-10k psi + hydraulic fluid + flexible = ? material
At 5000 psi, any plastic diaphragm will burst unless travel is limited by a strong housing.
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RE: 5-10k psi + hydraulic fluid + flexible = ? material
And Pat, thanks for the 5000 psi info, as that is significant to my design consideration. I know on most high pressure lines they are reinforced with steel cable or fibers, but are limited in flexibility.
RE: 5-10k psi + hydraulic fluid + flexible = ? material
RE: 5-10k psi + hydraulic fluid + flexible = ? material
RE: 5-10k psi + hydraulic fluid + flexible = ? material
Your local fire and rescue group might have a set that you can checkout.
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