Window Material and Calculations

[qui9]

I need to get a CRN# as a pressure fitting on a small sample cell that has fused silica windows at both ends to transmit UV light. Because of the geometry of the cell, I want to determine the maximum working pressure using the proof pressure test outlined in ASME VII Div 1 UG-101. The calculations all seem straight forward, at least for the 316L Stainless Steel that is used for the cell body, but I'm wondering if there is anything specific to materials and calculations for the windows or do I just apply the same derating formula from the proof pressure test?

I'm just wondering because I would have thought that glass materials would have a more conservative derating than metallic materials.

 

[deanc]

I would be more concerned with the fusing. Use the most conservative value and treat it as a flat head.

If you proof test to failure-that is the value you use.

 

[qui9]

Thanks for the reply deanc,

The windows at the end of the cell are not fused, but are sealed with o-rings. I will proof test to failure, but was wondering if there was any special consideration because of the non-metallic material being used for windows. Thanks again.

Kevin

 

[unclesyd]

Take a look at this site.

http://www.gequartz.com/en/pressure.htm

 

[qui9]

Unclesyd,

Thanks for the link - quite a useful site.