Charpy Requirement

[MechEngineerNJ]

Swet:

Hi guys I have the product which is going for DNV certification and the one of the plate is needs to be made out of Astralloy. The thing is that material certs shows 32 ft-lb average value for charpy impact testing at 32 deg F and the requirement is 31 ft-lb average at -20 deg C. Does any one have idea that this material will pass the test requirement.

 

[metengr]

dec1978;
This plate is a high strength, abrasion resistant grade of low alloy steel. I believe it will be doubtful if the CVN at 0 Deg C (32 deg F) is 32 ft-lbs, and you need 32 ft-lbs at -20 deg C. All you can do is to run a CVN test and see what happens.

 

[salmon2]

I second metengr, very unlikely.

 

[HgTX]

I third. Chances of getting the same value at -20C as at 0C are slim.

Hg

Eng-Tips policies: faq731-376

 

[stanweld]

Monel alloy is often used at the top of the Crude column and may be used in the overhead condenser (in you case shell side). Optimum materials selection is predicated on corrosivity of the fluid (actual constituents) at the operating temperature.