Required bolt loading for channel head to shell connection with fixed tubesheet in between

[DanTh3Man]

Hello,

I am trying to determine the bolt loading requirements for the channel head to vessel shell connection on one of our heat exchangers. There is a fixed tubesheet between the two flanges.

Searching for an approach to calculate the bolt loading requirements for this type or arrangement has not turned up much. My thought is that I can use BPVC Section VIII Mandatory Appendix 2 to calculate the required loading for the gasket on each side of the tubesheet and then add the two together for a total required bolt load - does this make sense?

Thank you for any input that you may provide.

 

[SnTMan]

DanTh3Man, Appendix 2 has specific provisions for this, a flange pair. See 2-5(a)(2). Also Part UHX-4(c).

Basically the highest required bolt load for each of the flanges, for both operating and gasket seating conditions is calculated. This highest load is then used for design of both flanges. It is essential to account for pass ribs, if any.

Note that this is for design ONLY. Assembly loads (bolt stresses) will generally be higher, sometimes much so.

Regards,

Mike

 

[DanTh3Man]

Thank you for the reply Mike. Now that you have mentioned that paragraph I feel quite silly for missing it.

I am accounting for ribs as per TEMA RGP-RCB-11.7 Pass partition rib area.

I will also look at applying PCC-2 Appendix O to this issue and see what I can come up with.

Regards,

Dan

 

[SnTMan]

Sounds like you're on the right track