AHartman
Mechanical
- Sep 17, 2010
- 32
Hi all,
This is my first foray onto these forums, having found them via a google search. I'm a mechanical engineer with access to Mechanica FEA in ProE. I've not done any B&PV designs before.
I have a mostly rectangular (rectangular but for a square removed from one corner) vacuum chamber flange which is 450 mm x 200 mm, and sealed with an o-ring whose groove is in the mating part. The chamber is evacuated and so the pressure delta is 1 atm in use.
My question is how does one model the deflection of such a flange to see if vacuum leaks will occur? My first blush attempt was to simply fix a strip of material on the bottom of the flange, following the contours of the footprint, then apply a uniform 1 atm load across the top surface.
This gave reasonable results, but it doesn't really tell me if the seal will fail, since I explicitly told the FEA system that my region of interest is fixed. How does one apply constraints to such a system? After the o-ring is compressed, there is metal-to-metal contact, but I can imagine that under enough central deformation, the corners of the flange could flex up sufficiently to cause a leak.
Can anyone offer some advice, or point me in the direction of some helpful reference material?
Thanks,
Adam Hartman
This is my first foray onto these forums, having found them via a google search. I'm a mechanical engineer with access to Mechanica FEA in ProE. I've not done any B&PV designs before.
I have a mostly rectangular (rectangular but for a square removed from one corner) vacuum chamber flange which is 450 mm x 200 mm, and sealed with an o-ring whose groove is in the mating part. The chamber is evacuated and so the pressure delta is 1 atm in use.
My question is how does one model the deflection of such a flange to see if vacuum leaks will occur? My first blush attempt was to simply fix a strip of material on the bottom of the flange, following the contours of the footprint, then apply a uniform 1 atm load across the top surface.
This gave reasonable results, but it doesn't really tell me if the seal will fail, since I explicitly told the FEA system that my region of interest is fixed. How does one apply constraints to such a system? After the o-ring is compressed, there is metal-to-metal contact, but I can imagine that under enough central deformation, the corners of the flange could flex up sufficiently to cause a leak.
Can anyone offer some advice, or point me in the direction of some helpful reference material?
Thanks,
Adam Hartman