Use of high strength bolts in low temperature

Guess you will have to freeze some and load test them.

Have the supplier certify them as such, in writing.

I am not familiar with the codification of steels you mention. I could try to give you a hint if it is possible to get following information:

- chemical composition of material

- nominal dimension of the bolts (thread + pitch)

- stress level statical + dynamics

Please refer to ASME code, Section VIII, Div. 1 [Fig. UCS-66], the bolt material: SA325 Grade 1, dia. up to 13 mm is exempted from impact test up to -30⁰C. For -40 ⁰C, impact test is required.

For the bolt material: SA490, I have no information.

As the other friends said "Get in writing from seller"

If you want these bolts to perform very well at -40Celsius

And you want only a few

And nobody will guarantee in a legally binding insurance- then look at this:

http://www.freepatentsonline.com/3955971.html Abstract: A weldable, low-alloy steel for Arctic service consisting essentially of 0.06 to 0.12% carbon, 0.40 to 1.00% manganese, 0.75 to 1.50% nickel, 0.50 to 1.25% chromium, 0.15 to 0.40% molybdenum, and up to 0.75% copper, with total copper plus chromium not exceeding 1.50% max. I am sure there will be some supplier of steel rods like above in Canada/Russia. Get these machined to sizes you need. Another possibility-Ask Canadian suppliers of wheel bolts/nuts for ice-duty Scrapers.

High strength bolts

Ask supplier for mechanical properties tested at that temperature and determine whether it will meet the specified loading in the design with your design safety factor considered.

or you could take these bolts and perform independent tensile and inpact testing.

Most manufactures should be able to provide shear, impact and tensile properties.

Hi, AISC and API 2C did specify requirements of bolts used and testing required (but is for off-shore pedestal crane). The ASTM for A329 and A490 bolts do mentioned the mechanical properties and testing requirements for these bolts.

It is common that we will request mill certificate from supplier on the material used, which shows the mechanical testing as required in the code and impact testing to -40 or less accordance to standard. Consideration should be given also if a lot of quantity is to be used, i.e. the process of manufacturing as the bolts are normally made from high strength carbon steel and possibly going through other additional process which include e.g. carburizing, surface hardening which may affect its mechanical property as specially impact strength.

In additional, you can carry out sampling test and test at recognise test lab for compliance tests; proof test (bolt & nuts), tensile, impact, micro-structure / metallurgraphy study (if necessary). Bear in mind, all tests are to verify the compliances of the products to the strenght, design factors and considerations, environment / wheather, temperature and services conditions and the loads applied for during the bolt connection designed.