Do you know about the term; controlled rolled !, normalised rolled?

Asme Sec.II Part A, SA 20 defines the heat treatment condition as normalised or heat treated conditions and how and by whom that conditions are achieved.
But, on some of the mtr's heat treatment condition is defined as controlled rolled, or normalised rolled condition without giving temperature, holding time etc.
Can these conditions thought to be normalised? or not.

No, Sir.

Controlled rolled is not "normalized",
normalized rolled is not "normalized",

according to the definitions in SA-20, normalizing means RE-HEATING to a temperature above the upper transition temp and a cooling in still air. Since the cooling is part of the process, the rolling at temperature is only one aspect.

The MTR shall address the temperature, holding time and cooling condition. Otherwise the plate is not considered NORMALIZED withe the effects on impact exemptions.


DK

Dr Koelbl,

Can you please provide code reference which require specifying cooling condition for normalizing cycle.

I came across many MTC which specify only normalizing temperature and holding time. During clarification one mill informed cooling rate as 720 Deg C/ hr which appears to be accelerated cooling, can we consider it as normalizing??

Whether NACT (Normalized, accelerated cooling, and tempered) plates where accelerated cooling is employed after normalizing can be considered for excemptions applied for normalizing plate (as per SA 20, cooling in still air).

Regards

Sanjeev

Sanjeev,

SA-20 says
3.1.8 normalizing — a heat treating process in which
a steel plate is reheated to a uniform temperature above
the upper critical temperature and then cooled in air to
below the transformation range.

The cooling is not required to be listed on the MTR by SA-20.
However, when listed, it shall meet the requirements.

DK

Dr. Koelbl,

Thanks for your reply. Can we consider accelerated cooled plates as normalized plate and for excemption of impact test.

Regards

Sanjeev

No, please read the definition in SA-20.

Dr. Koelbl,

Thanks for your replies.

Recently I came across some SA 516 Gr 70 NACT(nornalized + Accelerated cooled + tempered) plates from some reputed mill where tempering temperature is indicated as 590 Deg in MTC.

As per SA 516 Gr 70, section 5.4


Same statement is in SA 20 also.

Supplied plates have been certified as SA 516 Gr 70 by the mill and accepted by inspection agency including AI even though tempering was carried out at 590 Deg.

Am I missing something, is there any code case for this.


Regards

Sanjeev