o-ring flange seal

[93998453]

I used some specs to design a flange o-ring seal.
This design has water as the working fluid but i need air as the working fluid.

My pump is a balloon pump with very low pressure (less than 1 mpa). A piston fits into the hole in the cylinder I designed and pushes upwards. The cylinder has two flat covers at both sides.

The dimensions in the attachment are in millimeters. Please help me make an adjustment. I am not sure if my groove is placed correctly on the cylinder. I basically need help in dimensioning the groove.

 

[MikeHalloran]

What the hell does "MOST IMPORTANT DIMENSION" mean?

Get a Parker handbook, figure out the tolerances, and PUT THEM ON YOUR DRAWING.

Without a single tolerance, all you have provided is a sketch.



Mike Halloran
Pembroke Pines, FL, USA

 

[iainuts]

Using the Parker handbook is certainly the right way to do it. But the design as it stands is reasonable. Pressure is very low and initial crush on the seal is good, though a bit high. It's hard to screw up on an O-ring seal, especially at low pressure and static applications like this.

Your drawing is fine as is, though I'd make the groove a bit deeper. Generally a 15-20% crush on the seal is all that's needed. The crush on this one is over 25%. Add a note to your drawing showing tolerance of +/- 0.04 mm and you're done.

Note the cylinder design should also consider compressive forces. Make sure the compressive stress where the groove is isn't so high it's going to exceed the allowable strength of the cylinder, and not so low that it can't resist the axial forces created by the pressure.