Hello,

The following is mentioned in ASME B16.5

"When the ring joint or spiral wound gasket is selected, it is recommended
that line flanges be of the welding neck or
lapped joint type." 5.4.1, ASME B16.5, Page 4

Why is it not recommended to use spiral wound gaskets with slip-on flanges?

Thank you very much.

Regards,
Sharjeel

I presume that's because of their stiffness. Hubbed flanges are more stiff than slip-on ones, and these type of gaskets need higher bolt loads. Apparently, someone has seen failures on slip-on flanges and the standard discourages designers to follow that practice. However, this is a recommendation only, and good reasoning might ensure you/your client/your inspector that in a specific case there's no threat to the stiffness/leak tightness/bolt bending. I would check the flange stiffness requirement from SecVIII-1 UHX (somewhere at the end). There are more engineering codes that have provisions regarding this. This useful software might help: http://www.spetech.com.pl/#EUROPARTNER®

Regards

_________________
Konrad Anikiel