Steel for high temperature with saturated water

[vof1966]

Hello,

We are in the process of choosing a right steel for a singular application. Really, it wouldn't be special (it is just producing saturated steam at 60 bar inside tubes) but in this case we have to deal with very high metal temperatures (about 600ºC = 1100 ºF). The responsible of these uncommon high temperatures is a high heat flux.

We first thought on stainless steel TP304, but is it a right option? This boiler is to be stopped every night, and we suspect there could be corrosion, no matter on how chloride-low the feedwater is.

But we need a steel having good allowable stress at 600ºC/1100ºF, and this is not so easy. Maybe T91, having some Vanadium content?

We cannot use a sophisticated, very expensive alloy.

Many thanks for any opinion you can give.

Regards,

Maximo Calderon

 

[metengr]

At 1100 deg F you are pushing the limit of ferritic materials. You would be better off with ASME SA 213 TP347H material at this pressure and temperature.

Make sure that all tube bends and tubing are properly solution annealed - no local cold work should be performed on stainless steel in a boiler application.