Integral Ring flange with a full face gasket 3

[Mandy]

Hi,

Does anyone have experience with design of a ring flange with a full face gasket.

This flange is an optional kind and is being analyzed as an integral flange (sketch 8 fig 2-4 in App 2 ASME Sec VIII Div 1). The flange id is same as the pipe id. (Pipe is integral with flange).

Gasket is over the flange (not extending above the pipe). So, the gasket id is different from the flange id. This may create some issues with the procedure outlined in Taylor Forge bulletin for full face gasket flanges. For one the computation of hg:

hg = (C-B)(2B-C) / (6*(B+C))

B = flange id and C = bolt circle dia,

assumes the gasket id is same as flange id (B).

I think using flange id in place of 'B', can allow me to design ring flanges with full face gaskets as integral flange.

Input is appreciated.

 

[dugal]

Hi Mandy,
We use aluminum limiting rings with 1/8&quot; thick or less EPDM rubber rings lightly glued inside the thinner limiting rings. The rubber ID was slightly larger than the ID of the flange sealing face. The rubber OD was also smaller than the flange sealing face. When you tightened up on the flange the small portion of the aluminum limiting ring would prevent gasket crush, give you perfect compression and you could go all the way up to 50+ % of the bolt yield strength. You would not get further gasket creep. Spiral wound gaskets work on similar idea but they are prone to some creep. The OD of the aluminum limiting rings is just the right size to center the gasket between the studs. We use these gaskets on < 100 psi water. They are relativley cheap, full proof and perform very well.

 

[deanc]

If I understand your question,think you have all you need in App.2 and don't see any problems. Don't worry if there are conflicts with the Taylor Forge Bul. Its not mandatory.

 

[arto]

There's a new[?] WRC Bulletin on Flat Faced Flanges:
#314 &quot;Bolted Flanged Connections with Full Faced Gaskets&quot; May 1986. $50 from

http://www.forengineers.org/pvrc/wrcpvrcbulletin.htm

They have lotsa good stuff.
Maybe you can get it at an Engrg College Library

 

[prex]

Did you try the BS5500 procedure for full face gasketed flanges?
The inner gasket diameter has no influence on this calculation, as the tightness diameter G is assumed to be close to the inner periphery of the bolt holes.
In the site below there a calculation sheet for this.

prex

http://www.xcalcs.com

Online tools for structural design

 

[aybee]

Hi Mandy, I have had a very quick look at this and if I were doing this design I would use the flange ID as the B value for the parts which relate to the pressure forces and the gasket ID to get the effective gasket width b value for the gasket seating force section as one relates to the pressure force moments and the other to the gasket seating loads ..hope this helps
Aybee

 

[Mandy]

Thanks for your replies.

Regards,
Mandeep