BOLTUPprocedure for high temperature service
BOLTUPprocedure for high temperature service
(OP)
Hi people,
I've opened this thread because I did not find a proper discussion about this matter.
I have to prepare a Boltup procedure for an equipment in 304H Asme B31.3 with design temperature 760°C
pressure 350Kpa standard flange Asme B16.5 24" 300# with spiral wound gasket with thermiculite, bolt
material A193Gr.B8m (170Mpa/15Mpa allowable 20°C/760°c, mandatory).
The question is that client asked to comply with Asme VIII D.1 appendix 2 and wm1, wm2 have to be verified,
situation is as follow 140275kgf/170Mpa and 16734kgf/15Mpa respectively it means the bolt area required depend on operating
condition wm1, but which will be the tensioning at ambient temp. 20°C to each bolt wm1/nos.bolt or wm2/nos.bolt ????
If I use tensioning with presetting condition the stress will be too much high at operating > than allowable stress
of the bolt at 760°C =15Mpa.
I've opened this thread because I did not find a proper discussion about this matter.
I have to prepare a Boltup procedure for an equipment in 304H Asme B31.3 with design temperature 760°C
pressure 350Kpa standard flange Asme B16.5 24" 300# with spiral wound gasket with thermiculite, bolt
material A193Gr.B8m (170Mpa/15Mpa allowable 20°C/760°c, mandatory).
The question is that client asked to comply with Asme VIII D.1 appendix 2 and wm1, wm2 have to be verified,
situation is as follow 140275kgf/170Mpa and 16734kgf/15Mpa respectively it means the bolt area required depend on operating
condition wm1, but which will be the tensioning at ambient temp. 20°C to each bolt wm1/nos.bolt or wm2/nos.bolt ????
If I use tensioning with presetting condition the stress will be too much high at operating > than allowable stress
of the bolt at 760°C =15Mpa.





RE: BOLTUPprocedure for high temperature service
I would recommend that you retain the services of a bolted flange joint specialist to assist you with this situation. Those temperatures need special treatment - more than can be provided free over the anonymous internet.
RE: BOLTUPprocedure for high temperature service
There are your requirements.
Now, I don't know "thermiculite" and so will NOT make assumptions about "thermiculite", but when I want to know how to bolt up a flange around a Flexitallic gasket, (or a soft rubber gasket or a permaflex gasket) I go to the Flexatallic website and look up the specific torque sequence and torque values for the gasket I am using.
Your bolting sequence and the intermittent torque values on the studs at each intermediate level are set BY the gasket material. NOT by ASME or the "code" .
RE: BOLTUPprocedure for high temperature service