An Efficient Heuristic for Planning Mother Plate Requirements at Bethlehem Steel

So that Bethlehem Steel's Sparrows Point plant can produce narrow-width (NW) customer-plate orders (typically 10′′ to 24′′) efficiently when its 60′′ plate mill is not operating, we developed a heuristic procedure to map these orders into mother plates for production on its 160′′ plate mill. Mother plates processed on the 60′′ plate mill are cut, using fairly simple, two-stage guillotine cutting patterns, into a few NW customer plates. Considerably more NW plates can be cut from the much larger mother plates processed on the 160′′ mill, and the number of possible mappings of NW customer plates into mother plates is much larger. Our heuristic procedure was implemented as a module in the plant's production planning and control system, and it is used daily to generate mother-plate dimensions and cutting patterns.