zcp;

Yes. What is the material? What was the weld metal used for fabrication? Was the stand post weld heat treated? Was there nondestructive testing performed of the fabrication welds? Were the welds fillet or full penetration?

I am asking the question in general for structural steel design.....if I am using a36, a992, a53, etc., what needs to change when the intended service will be in cold environments? (material, welding, requirements, etc.)

ZCP
www.phoenix-engineer.com

zcp;
For low temperature service, you need to;

1. Select a suitable material based on impact test requirements for low temperature service.
2. You need to qualify a weld procedure with impact testing to assure proper selection of filler metal for low temperature service and welding requirements - like preheat and post weld heat treatment (if necessary).
3. You need to specify weld detail to assure adequate stregnth and to avoid any stress concentration (as would ocurr with fillet welds)
4. You need to specify nondestructive testing after fabrication.

See AWS d1.1 app III

General structural steels are not suitable fo - 50 Deg. C

Any suggestions on what might be suitable?  .....(hypothetically) for an outdoor steel stand 8 or 10 ft square, 15 ft tall that has a storage bin on top for small misc equipment (light loads).  Are we saying normal structural steel shapes are out because it might get down to -50 deg C for a day or two once every year or two?  What should be used that would not be prohibitively expensive?

If impact (high strain) loads are prevented, is there even a problem? If the stresses due to max loads are low, is there anything to be concerned about?

I am looking for anyone's opinions and experiences.......thanks

ZCP
www.phoenix-engineer.com

Your going to need low alloy steel plates that contain nickel for low temperature service. Look through an ASTM Standards Index on Iron and Steels - Structural and see what you can find.

Another option is to construct the stand out of an austenitic stainless steel. This will virtually eliminate any problem with low temperature service.

Look at Tables 4.1 and 4.2 in AWS D1.5-2002 for Zone III.  Also ASTM A 709-07 Table 9 for Zone III.

Hg

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