Max. use temp. on 904L material 1

[XL83NL]

We currently have a job where we need to design some 904L piping. The request is to use this material for a design of 300°C.

B16.5 p,T-ratings are OK for 300°C and even good up to 375°C. ASME II-D (Metric, 2019, page 248, lines 20÷27) lists N08904 up to 371°C.

B31.3, the piping code we're working to, 'limits' this material to a max. use temp of 260°C per table A-1M. Although such limits in B31.3 are not as hard as e.g. those in IID, these limits (afaik) are usually limited by some sort pf material degradation mechanisms that comes into play at a certain temperature.

I wondered if anyone has any idea or thoughts about any possible material degradation mechanism or the like, for 904L in this range, that could limit the material's 'safe' temperature range.

Huub
- You never get what you expect, you only get what you inspect.

 

Are you right to be concerned about corrosion as well as just strength - Code only cares about the latter.

904L will undergo metallurgical alteration above a certain temperature; I suggest you start by searching for manufacturer's product data sheets.
Special Metals is my go-to source, I think they offer 904L. Also the Nickel Development Institute; look specifically for their sulphuric acid guide.


"Everyone is entitled to their own opinions, but they are not entitled to their own facts."

 

[XL83NL]

Thanks IM. I understand corrosion is 1 thing, strength is another. Codes aren’t cook books and are not all-inclusive when it comes to design.

As an example for SDSS, the code limits this material at approx 315C, if I’m not mistaken. This is for metallurgical reasons, just the point I’m referring to.

You mentioned metallurgical changes. Which? I’m looking for info. Couldn’t find any in the datasheets on the interwebs. No special metals, no ATI, no Sandvik. Not looking for what happens when one uses 904L with sulphuric acid or any other form of corrosion, even though such mechanisms matter and may set a limit to the use of any material far below any temperature due to metallurgical reasons.

Huub
- You never get what you expect, you only get what you inspect.

 

[EdStainless]

What material are you handling?
Remember that corrosion is exp with temp.
This alloys should be metallurgically stable up to 500-550C.

https://nickelinstitute.org/media/1702/highperformancestainlesssteels_11021_.pdf

= = = = = = = = = = = = = = = = = = = =
P.E. Metallurgy, consulting work welcomed

 

[SJones]

From Sandvik 2RK65 datasheet:

At high temperatures
The steel should not be exposed to temperatures above about 550 °C (1020 °F) for prolonged periods, since this
leads to precipitation of intermetallic phases, which can have an adverse effect on both the mechanical
properties and the corrosion resistance of the steel. Minimum proof strength properties at high temperatures are
based on datasheets seamless tubes and pipe.

https://www.materials.sandvik/en-gb...asheets/tube-and-pipe-seamless/sandvik-2rk65/

Steve Jones
Corrosion Management Consultant

http://www.linkedin.com/in/drstevejones

All answers are personal opinions only and are in no way connected with any employer.

 

[XL83NL]

Thanks guys, sufficient input for now!

Huub
- You never get what you expect, you only get what you inspect.