steel low temperatures standards

[Appl3E14159]

Hello,

Can anyone please explain me how can I know the minimum ambient temperature According to steel standards? for example s235 and st37.

If the steel passes impact test in (-)20°c, according to the standards, that means the steel can stand at (-)20°c and not below?
Or - I can choose the minimum temperature according to the steel uses, load, and mechanical properties at specific temp.? In this case the standards are only for recommendation?

Thanks.

 

[denlow60]

Look in NEN-EN 10025-1 to 10025-5

 

[denlow60]

Look in NEN-EN 10025-1 to 10025-5

 

[moltenmetal]

When structural steel is used in very cold ambient environments (i.e. Alberta), rarely is a "killed" low temperature structural steel specified. Rather, thicker sections of ordinary structural steels are used. Specify what you like, but if you can't get it, you can't build with it.

 

[Appl3E14159]

denlow60 and moltenmetal, thanks for the answers.

denlow60 - for now I don't have in reach the EN 10025:1-5.
But from Google search I didn't find any help how to determine the minimum ambient temperature that steel profile or plate can be use.

moltenmetal - if I understand you correctly I can use "ordinary" steel, like s235jr, but use thicker plate or profile.

Maybe it's stupid question but why we need the impact test that EN require?

 

[moltenmetal]

Note that this practice of using ordinary (-20 F) structural steels with reduced stress values, perhaps also with a somewhat more stringent impact testing requirement and more care around the selection and qualification of welding materials and processes etc., is common for structural applications in cold climates in my experience. That doesn't mean that certain applications, locations etc. don't require true low temperature steels- but then you need to find structural shapes made from those steels, which is difficult unless you're ordering a LOT of a particular section and can dictate the nature of the source steel. Plate? You can always find plate, but then the welding can be the issue.

In pressure vessels, for low ambient temperature or autorefrigerating gas applications for pressure vessels and piping, low temperature steels or even stainless steels are required- no option. But where it gets silly is where people start specifying low temperature steels for services containing water...

 

[denlow60]

I have a table for some examples here .