Materials/standards for high temp/pressure vessel...

[someguy2]

We need to build a small (250ml) test vessel that holds steam at 2000 PSI and 1600F or thereabouts. On first look, we are thinking of using 316H stainless.

a) what is the best guide to the stress/temp abilities of various steels, such as 316H.

b) what ASME documents should we be using to design said vessel ?

We will probably bring a consultant into this project. I want the above information to get background on the problem before we do.

Thanks.

 

[metengr]

) what is the best guide to the stress/temp abilities of various steels, such as 316H.

b) what ASME documents should we be using to design said vessel ?

Despite the small volume (250 ml) this type of vessel should be designed and fabricated in accordance with ASME Boiler and Pressure Vessel Code or an equivalent foreign standard (outside of the US).

The particular section of the ASME B&PV Code that you should use is Section VIII, Div 1, which applies to unfired pressure vessels.

My suggestion is to indeed hire the necessary expertise for pressure vessel design to Section VIII. Regarding suitable materials, ASME B&PV Code, Section II provides a comprehensive list of materials based on use at service temperature. At 1600 deg F your alloy selection will probably be limited to Ni base (non-ferrous) alloys.

 

[stanweld]

While the size of the test vessel is outside ASME VIII, I agree with metengr unless you have designing capabilities that take into account a very short term life requirements of the vessel under the load and temp conditions. Alloy X, Alloy 617, Alloy 800H have all been used in 1600F PV applications.

 

[someguy2]

The 1999 Addenda, Secion VIII, Division1 Table 1A lists the maximum design stress for 304H and 316H to be 1400 and 1300 PSI at 1500F. We will lower our vessel temp to 1500F and stick with stainless steel.

Some of the super alloys will go to higher temperatures, but the cost doesn't seem worth it at this time.

I don't see any values for 316Ti. Does anyone know if they would be higher ? (Just curious, not saying we would use it anyway...)

Thanks.

 

[metengr]

No. There is no benefit to be gained in increased allowable stresses for pressure retaining components from the Ti, the carbon content is the major contributor.