What Is HMS 1 and HMS 2? A Buyer’s Guide to Heavy Melting Scrap

If you buy or sell steel scrap, HMS 1 and HMS 2 are the two grades you will meet daily. They decide what your machine can process, what your buyer pays, and which tonnage class of shear your material actually needs. This guide explains the grades in plain terms and maps them to the machines on this site.

The Short Definitions

HMS 1 is heavy melting steel scrap: wrought iron or steel pieces at least a quarter inch thick (about 6 mm), prepared to size so they fit into a charging box, and free of excessive non-metallic attachments. Think plate offcuts, section steel, structural members, machinery parts — solid, dense, well-defined pieces.

HMS 2 is the lighter and thinner companion grade: thinner steel, often galvanized or with more attachments, that still melts but prepares less cleanly. Thin sheet, light structural, coated material.

The practical difference between them is twofold: density (how much fits in a charging box) and preparation (how much work remains before melting). Both affect price, and both affect which machine handles the material.

Why the Grade Matters to Machine Selection

Machine capability is specified by material thickness and grade, not by weight. A gantry shear rated for HMS 1 in a given tonnage class may take the same grade only at thinner dimensions on another class. The material capability table on each product page states the honest range for that model.

For buyers, the rule is simple: your heaviest HMS 1 pieces set the minimum class. HMS 2 and light material can sit lower on the ladder, and thinner material is easier on blades and frame. The mistake is sizing for your average material instead of your heaviest.

HMS 1: The Shear’s Home Ground

HMS 1 is what gantry shears are built for. Plate offcuts, section steel and structural offcuts cut cleanly at the right tonnage class, and the cut pieces go straight to furnace charging or into a baler for density. Yards whose feed is dominantly HMS 1 with two-shift duty typically land in the mid to large classes; single-shift light HMS can sit lower.

Two operational notes from real yards. First, pre-size to your chamber — a piece too large for the box forces pre-cutting that labor could have avoided with a slightly larger chamber. Second, weldments and attachments: HMS 1 specification frowns on them, and they accelerate blade wear when they appear anyway.

HMS 2 and Light Material: Different Machines

HMS 2, thin sheet and light steel often never need a gantry shear at all. Light material sizes easily on an alligator shear, which is cheaper to buy, needs minimal installation, and can follow portable duty. Buying gantry force for rebar and light offcuts is the most common overspend in this business.

Bulky mixed waste that must be reduced to small clean fraction is not shear work at any tonnage — it is shredder work, where liberation and downstream separation do what no cutting machine can.

Telling the Grades Apart at the Gate

Yards classify inbound material by inspection: thickness, coating, attachments and density. A few practical habits:

• Thickness first. Under about a quarter inch and it is not HMS 1 regardless of what the paperwork says.
• Coatings count. Galvanized and coated material grades as lighter and prices accordingly.
• Attachments reduce grade. Fittings, non-metallics and assemblies drag material down even when the steel itself is heavy.
• When in doubt, sample. For unusual streams, get suitability confirmed against your machine’s specification before committing to a processing route.

HMS Grades FAQ

Can HMS 2 be baled instead of sheared?

Yes. Light steel scrap is baler material, and many yards process HMS 2 straight to bales without any cutting stage. The deciding factor is whether the material needs sizing before your buyer accepts it.

Does galvanized material damage shredder blades?

Zinc coating is softer than blade steel, so it wears blades faster through abrasion than through impact — noticeable, not catastrophic. The bigger enemy of blades in coated material is the grit and soil that travels with it.

Which grade gives better payback on a shear?

Heavy HMS 1 in volume, because cutting force applied to suitable heavy material is the cheapest processing there is, and the cut product sells clean. Yards processing mostly HMS 2 should honestly evaluate whether an alligator shear plus a baler covers the job at lower cost.

How do I know if my heaviest HMS fits a given machine?

Compare your heaviest pieces against the material capability table on the product page, with margin. If your heaviest items sit at the top of the published range, move up a class — running at the limit shortens blade life and stresses frames.

Can one yard process both grades profitably?

Most do, by separating streams at intake: heavy HMS 1 to the gantry shear, light material to the alligator shear or straight to the baler. Sorting at the gate is cheaper than forcing one machine to do both jobs poorly.

Match the Machine to the Grade, Not the Wish List

Send us your three heaviest items and the typical mix of HMS 1 versus HMS 2 in your inbound, and we will recommend the machine class against real capability data — including an alligator shear when that is the honest answer. Every quotation is factory direct and returns within two business days.

Explore the shear range, the baler range, or contact our team with your material list.