Duplex 2205 for High Pressure Piping 1

[bks2000]

Does anyone have any ideas why ASTM 240 is not listed as a specification in ASME 31.3 Appendix K (the Allowable Stresses Table for Chapter IX High Pressure piping)?

Does anyone know of a reason it would not be a suitable material for high-pressure?

 

[bks2000]

Sorry, the spec I referenced should have been ASTM A789...the A240 is for plate.

I guess there is no way to edit a post after I've posted it.

 

[BigInch]

I FOUND IT!

B31.3-2008 Page 139
Specification Index for Appendix A (Cont’d)

A 789 Seamless and Welded Ferritic/Austenitic Stainless
Steel Tubing for General Service

26Cr–4Ni–Mo A 789
26Cr–4Ni–Mo A 790

P/S no. Grade Note MinT Ten Yield 100F .. NO MORE
S-10H S32900 (25) ?20F 90ksi 70ksi 30.0ksi .. NO MORE

Note(25)
This steel may develop embrittlement after service at approximately 316°C (600°F) and higher temperature.

**********************
"Pumping accounts for 20% of the world’s energy used by electric motors and 25-50% of the total electrical energy usage in certain industrial facilities."-DOE statistic (Note: Make that 99% for pipeline companies)

http://virtualpipeline.spaces.live.com/

 

[bks2000]

BigInch,

Thanks. I did not check Appendix A since I was so focused on the high pressure requirements of my application (10,000 PSI). What I'm really asking is, if this material is so strong, why would it not be listed under Appendix K? Or am I being too careful? (Hard to imagine being too careful with such a high pressure).

Is it appropriate to use this for high pressure?

Thanks

 

[bernoullies123]

Refer to section K323.1.2 Unlisted Materials.

Some checks would need to be performed.

 

[BigInch]

I have not used this material. Its yield strength would suggest it is appropriate for high pressure, but high and low (< -20F) temperatures should be avoided.

**********************
"Pumping accounts for 20% of the world’s energy used by electric motors and 25-50% of the total electrical energy usage in certain industrial facilities."-DOE statistic (Note: Make that 99% for pipeline companies)

http://virtualpipeline.spaces.live.com/

 

[rneill]

I have used 2205 Duplex material in a High Pressure Application (7200 psi design pressure) previously. If I recall, the pipe wall thickness was over 2". Our design temperature was around 140 F and we used the allowable stress values of Appendix A. We did not use the high pressure rules to justify using a less conservative allowable although that was in part because the rules at the time were not clear about the acceptability of higher allowables for design temperatures above 100 F.

 

[MJCronin]

A few other items should be discussed:

Duplex stainless steels(2205) have a limit on the maximum temperature for continuous operation.

Continuous operation above ~600F leads to embrittlement. Some vendors recommend lower limits.

Where the chlorides exceed certain maxima, some 2205 vendors suggest an upgrade to the welding materials. This should be considered when pH of the liquid is less than 5.0

My opinions only...

-MJC