In ASME IX-1998 , QW-452.1 the welder gets an unlimited deposited weld metal range after welding three layers at least 3/4 inch thick with one filler metal.
In ASME IX-2001 the QW-452.1 was changed into QW-452.1(a) and QW-452.1(b). To get an unlimited range the welder has to apply 3 layers and a minimum of 1/2 inch weld deposit with one filler metal.
"Max to be welded" is the same as saying "unlimited".
Regards, dlmann