360 degrees equal pressure?

[darren55]

Hello,

My name is Darren, new to the forum, I'm trying
to figure out how to apply equal pressure (around 40psi)
around a cylinder. Equal pressure 360 degrees around is
fundamental to the design, by this i mean bearings
cannot be used; also,it has to work for different
sized pipes without adjustment, I've thought of maybe
using flexinol? Any thoughts?

 

[sms]

Probably going to need a bit more than that, how big a cylinder, or what sizes of pipe? 2 inch, or 36 inch? Does it have to be exactly 40 psi? Is that the needed external pressure, or is that delta p between inside and out? If you pull a vacuum on the interior does it accomplish the same effect? Is that gauge or abs? What is the point?

-The future's so bright I gotta wear shades!

 

[JStephen]

That does seem pretty vague. You could make a set-up like a hydraulic cylinder and apply all the pressure you want to. Submerge it in a 100' of water, or put in pressurized container and it should do the same. Does it matter if pressure is applied to the ends as well?

 

[IFRs]

Put it in a bag and connect it to a vacuum pump. You'll get 10 psi easily.

 

[darren55]

I mean like rollers, rolling 360 degrees around the pipe
with no openings, and making the ring size bigger and smaller, rollers roll along the outside of the pipe,