The general requirement for a Plate mill would be to have an annealing/stress releaving facility to reduce hardness/stresses occurring due to work hardening.
MEaning no disrespect, but it would be helpful to tell us the plate material. It is presumptuous to assume that the plate mill is for steel, when in fact aluminum, Stainless steel or other materials are possible.
Also, what specifications are you planning to meet? IF these involve Quench and tempering of steel, then a different facility will be needed than mere Stress relief.
Help us help you. I don't write prescriptions before seeing the patient.
Milo
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