Gasket clearance for a bi-flange connection!!!

[gbratis]

Hi guys,
Could someone advise me on the gap that needs to be left between flanges for gasket utilization? I'm having a hard time to find a reliable source where I can obtain this info. Any suggestion? For example is 3mm (compressed) adequate clearance for a spiral wound gasket for a #600 flange? Is there a gasket type to pressure rating table with the applicable drafting clearance for a bi-flange connection.?
Respect!

 

[unclesyd]

Your gasket supplier or manufacturer has that information in their installation instructions.

If you use the torque values, assuming the proper bolting, recommend by the gasket manufacture or your calculated bolt torque values to seat the gasket this takes care of the gasket "crush" required to make the gasket seat.

 

[rconner]

I suspect many pipe drafters (at least in the absence of any over-riding or governing instruction or code) even for rubber gaskets probably just provide for a flange gasket space equal to the nominal gasket thickness in the layout, as other apparently tolerable variations in laying lengths and straightness of flanges etc. in pipes, fittings, valves etc. probably in most cases far exceed any actual compression length reduction that is realized, specifically in the normally very short/small thickness of the gasket itself. A long time ago I think I even had an old hand tell me that rubber, sort of like a fluid, basically more "flows" than it reduces in volume under load. Like you I will await any more knowledgeable response.

 

[NozzleTwister]

For Spriral Wound gaskets the normal gap between flange faces is 1/8" (3mm) provided that you're buying 1/8" nominal thichness gaskets. There are other thicknesses available but 1/8" thick is all I've ever seen.

The two maunufactures links below both have the info that you're looking for as well as downloadable PDF catalogs and design manuals.

http://www.flexitallic.com/

http://www.lamonsgasket.com/

Good luck,

NozzleTwister
Houston, Texas