How thick a tubesheet? 1

[moltenmetal]

When using large (2" NPS sch40S pipe) tubes in an exchanger, how thick does a tubesheet need to be to ensure a reasonable chance of sealing by roller expansion alone?

Materials are 800HT for both tubes and tubesheet (i.e. it's a HOT service). Service pressure is ~12 psig which is also ~ the max differential pressure across the tubesheet, so the tubesheet thickness required for pressure is pretty thin... Welding of tubes to the tubesheet is not an option due to access, though we'll be welding everywhere we can reach. Some leakage of the high pressure side through the tube to tubesheet joint is acceptable (and inevitable).

 

[TJOrlowski]

Contact the manufacturer of the tube rolling equipment you will be using. They should be able to tell you the length of the rolls required for expanding a 2.375" OD x .154 wall tube into a tubesheet.

You'll want at least 5/16" (8mm) of metal beyond where the roll will stop, so you don't expand the pipe past the tubesheet.

-TJ Orlowski