8″ PIPE B619 UNS N10276 EFW SCH 40 BE CLASS-1 Vs CLASS-2

Query :-

Dear Sir,

I critically compared your company Technical specifications Vs Vendor quoted Technical specification with reference to ASTM B619.
The first obvious difference is between Class-1 & Class-II , It seems to me that you are required to buy 8″ PIPE B619 UNS N10276 CLASS-1 EFW SCH 40 BE material from your vendor but the vendor is insisting you to buy Class-II material with additional recommendation on final HT.
Class 1 is designed to perform in more critical applications where higher assurance of the pipe’s integrity is necessary, such as in highly corrosive environments or where safety is a main concern.
Class 1 pipes are generally manufactured with STRICKER quality control measures demanding RT and UT both testings.

Where as, Class 2 are designed suitable for LESS  critical applications where the risk of failure is lower and the operating conditions are less severe.pipes meet the standard quality requirements but are not subjected to the same level of rigorous testing as Class 1.

For example, the vendor’s quotation specifies 100% RT of weld joints but does not mention 100% UT of the pipe body.

Anyways, the point of concern seem to me is Clause no. 6.2  of ASTM B519 which states that “Subsequent to welding and prior to final heat treatment,
Class II pipes shall be cold worked either in both weld and base metal or in weld metal only. The method of cold working may be specified by the purchaser.
So, I foresee a bottle-neck here. As after welding operation  you have to have some mecahnism to subject it to cold work (after welding and before final HT),

The Class-II material specifically demands Cold working operation (to induce some mechanical strength) and after welding and before final HT, where as, Class-I material does not. These differences may affect the final product’s quality and performance characteristics.

This is my submission from metallurgical point of view. I think, you should insist to Vendor to supply only Class-I material. 
To add in that , economically, Class-II are also NOT  viable due to increased cost of final heat treatment and likely distortion problem of water quenching.  Although, 8″ PIPE SCH 40 shall have 8.18 mm wall thickness so distortion may or may not happen.