Stainless steel vessel with carbon steel stiffener
Stainless steel vessel with carbon steel stiffener
(OP)
Hi Experts
I have a pressure vessel made of stainless steel designed for vacuum (design temperature 200 deg.C). I need to have stiffeners; according to design carbon steel stiffener is sufficient. From the point of view of welding, is it advisable to use only stainless steel stiffener?
(I have used stainless steel vessel to avoid problems due to erosion of steam flow.
thanks for your help
I have a pressure vessel made of stainless steel designed for vacuum (design temperature 200 deg.C). I need to have stiffeners; according to design carbon steel stiffener is sufficient. From the point of view of welding, is it advisable to use only stainless steel stiffener?
(I have used stainless steel vessel to avoid problems due to erosion of steam flow.
thanks for your help





RE: Stainless steel vessel with carbon steel stiffener
Of course you will need to protect the rings from corrosion, unless they are covered by the insulation.
prex
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RE: Stainless steel vessel with carbon steel stiffener
RE: Stainless steel vessel with carbon steel stiffener
I hope you have considered the differential expansion between the CS and the SS at the elevated temperature of 200Deg C as this could give rise to high stresses around the welds. Also it is general to not directly weld CS directly to the pressure part of a SS pressure vessel but introduce a SS section between.
RE: Stainless steel vessel with carbon steel stiffener
RE: Stainless steel vessel with carbon steel stiffener
RE: Stainless steel vessel with carbon steel stiffener
Please do not forget to use SS 309 ( high nicel content)electrodes for welding, to prevent welding zone from ferritic and/or martenize type of stainless steel formation ( instead of austenic- I assume vessel is austenic stainless steel)
zeki
RE: Stainless steel vessel with carbon steel stiffener
RE: Stainless steel vessel with carbon steel stiffener
To take care of differential expansion and corrosion problems of shell wall/welds, but still use CS stiffners, a small extra effort would generall do. First deposit SS 309 on CS ring then assemble the ring and then weld the ring to shell using SS 309 again.
RE: Stainless steel vessel with carbon steel stiffener
You have an entire vessel of stainless steel. What is your motivation for providing a carbon steel stiffener ring? To save money? How much will you save by choosing carbon steel over the same material, where expansion will not be a factor, where welding will not be different than for any other joint, where the obvious effects of corrosion will threaten the only design feature that keeps the vessel from collapse under vacuum??
Make it easy on your maintenance people and easy on your welders. Avoid unnecessary stresses on your vessel and make the stiffener ring of the same material.
RE: Stainless steel vessel with carbon steel stiffener
Thanks to all of you