HK-40 material at 2000F

[pbc825]

Good afternoon all. I hope you're enjoying Victoria Day if you reside in Canada.

I'm working on an FEA project for a valve in a power plant. The client has been a little vague on details, by I've been able to assume/calculate my way through to some loads. One stream at the T valve is subject to gas flow at 2100F and above the stream is closer to 700F. I've performed a thermal analysis and the important parts will operate between 1900F and 2000F.

I've read through volumes of threads on HK-40 material and understand it's typically used in high temperature applications. There is reference information provided by Kubota (a producer of the metal) stating stress-rupture stress values at various temperatures and durations as well as creep rates which has been helpful. However, as deflection is not driving the design, I'm most-interested in stress-rupture information. However, the stress rupture values at 100,000 hours stop at 1800F and 1900F for 10,000 hours. I know the material melts around 2500F; however, I'm interested to know if there are other sources of information (API 530 perhaps) listing allowable stress at either 1900 or 2000 F. Any help in this? The application has an expected lift span between 30,000 and 40,000 hours.

Thank you in advance for any responses.

 

[NBrink]

530 stops at 1750 for HK-40. The ASM Steel Castings Handbook goes up to 2000. Worth a look...

Nathan Brink

 

[weldstan]

If in an oxidizing environment, don't expect it to last that long.

 

[EdStainless]

9th ed of the Metals Handbook vol 3 on page 298 has 2000F data as well.
10,000hr is 0.72ksi and 100,000hr is 0.42ksi

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P.E. Metallurgy, Plymouth Tube

 

[pbc825]

Much appreciated gents. Thank you.