HMS stands for heavy melting scrap, and 1 & 2 are the two grades within that definition. They are widely traded, particularly in the western hemisphere. Both HMS 1 & 2 comprise obsolete scrap only. That is iron and steel recovered from items demolished or dismantled at the end of their life.
Both grades guarantee a minimum piece thickness – at least 1/4inch (6.3mm) for HMS 1, and 1/8in for HMS 2 – consignments have a high density. Both also have defined maximum dimensions (usually 60in x 24in), and should be prepared to facilitate handling and charging to a furnace.
This density, sizing and preparation makes for efficient furnace operation by minimizing the time to charge enough scrap for a full melt. In contrast, thin mixed scrap greatly increases charging time, cutting furnace productivity.
Variations on maximum piece size are covered by ISRI (North America’s Institute of Scrap Recycling Industries) codes. HMS is usually traded as a blend of 1 & 2, either a premium blend (80:20) or lower grade mixes (70:30) and (60:40). Other major heavy scrap grades include Japan’s H2 and A3 from the CIS.
All the consumer cans or packaging materials with ferrous contents are segregated by various sorting processes and then baled or compressed in to various sizes of bundles making is suitable for charging in furnace. ISRI 213 steel can bundles: Steel can scrap compressed to charging box size and weighing not less than 75 pounds per cubic foot. Cans may be baled without removal of paper labels, but free of other non-metallic impurities. It may include up to 5 gallon tin coated containers.
