Hello!


We have reviewed some MTC’s from Alchevsk Iron and steel works. On the first page are listed some CS (SA 516 Gr. 70 MT LTV) plates with EN 10204 3.2. On the second page, the same heat numbers are listed without mention of EN 10204 3.2 but it mentions form IV. What exactly is this form IV?


Secondly, some plates have impact energy of 25 J @ -46 ºC while others have a very high impact value of 140 J @ -46 ºC. Why is this variation.

I really appreciate your help and kind support in this regard.

Form IV is a specific form of certificate in Indian Boiler regulation (IBR), see http://dipp.nic.in/boiler_rules_updated/history.htm

Without knowing details about chemistry and thickness it is quite difficult to assess the reason for the scattering in Charpy values
Regards