Fiber Ring Joint Gasket - ASME Design

[svi]

The Klingersil C4430, a synthetic fiber gasket reports the following m and Y values for various thickness values vs the corresponding in ASME Sec VIII Div 1 Mandatory Appendix 2 for Bolted Flange design Table 2-5.1.

Klingersil C4430, Thickness mm, m, Y psi
1, 4.5, 3625
2, 5, 3625
3, 5.5, 3625
ASME Table 2-5.1, Thickness mm, m, Y psi
3.2, 2, 1600
1.6, 2.75, 3700
0.8, 3.5, 6500

It is seen the C4430 has a higher value of m and a constant value of Y for increasing thickness of gaskets. It is customary to use the higher thickness for larger flange size fibre joints. Whereas the ASME listing has a lower m value and a lower seating stress for increasing thicknesses.

Will this even out with the variation shown for C4430 or is it that the ASME criteria needs a review vs the material attribute. What about the joints in class 150 and 300 or other classes that uses these values for design, will it require an evaluation for the joint rating.

 

[SnTMan]

svi, are you designing Appendix 2 flanges? If so, I'd use the gasket manufacturers' numbers. Apx 2 values are generic and non-mandatory.

"Will this even out with the variation shown for C4430..." - What do you mean by this?

B16.5 flanges need no evaluation of bolt area vs. gasket properties.

Regards,

Mike

The problem with sloppy work is that the supply FAR EXCEEDS the demand

 

[KevinNZ]

Be careful. You should consider a range other gaskets materials for the flange design. Someone may use a gasket other than C4430 in the future change the stresses in the flange.