Opening pattern to your spec
Grid openings cast to the product size you actually need, not a single stock pattern.
Shredder Wear Parts
Shredder Grates & Grids
Grates and grids that set shredder product size, cast in manganese and alloy steel to survive the discharge zone.
Overview
About shredder grates & grids
Grates and grids control the product size leaving a shredder. Material stays in the mill until it is small enough to pass. That makes them a process control component as much as a wear part: as the openings wear, product size drifts and downstream separation suffers.
Melco casts grates and grids in austenitic manganese steel and alloy steel, in the section sizes and opening patterns each machine and product spec requires. Large single-piece grates up to 2,000 kg are within our range.
Because grates are heavy and awkward to handle, we pay particular attention to dimensional accuracy, because a grate that has to be forced into position wastes hours of downtime during a change.
Applications
- Automobile and scrap shredder discharge grates
- Hammer mill grid bars and screen sections
- Metal recycling lines needing controlled product size
- Replacement grates for Wendt, Metso and Lindemann machines
Features
What you get
Manganese or alloy steel
Grade chosen for the balance of impact and abrasion in your discharge zone.
Large single-piece castings
Up to 2,000 kg per piece, reducing the number of sections to handle during a change.
Dimensional accuracy checked
Verified against drawing before dispatch so grates drop into position without on-site fitting.
Specifications
Manufacturing specification
Applies to shredder grates & grids produced at our works. Castings outside this range can usually be accommodated, so please ask.
| Moulding | No-bake resin sand and green sand |
|---|---|
| Melting | Induction furnace, spectrometer-controlled |
| Piece weight | 5 kg – 2,000 kg |
| Heat treatment | In-house, computer-controlled cycles |
| Dimensional control | Template and CMM check against drawing |
| Documentation | Chemical, hardness and dimensional report per heat |
Material grades
| Grade | Typical composition | Hardness | Suited to |
|---|---|---|---|
| ASTM A128 Grade A | 1.05–1.35% C, 11.0–14.0% Mn | 200–229 BHN as-cast, 500+ BHN work-hardened | Standard high-impact duty |
| ASTM A128 Grade B-3 | 0.9–1.05% C, 11.5–14.0% Mn | 200–229 BHN as-cast, 500+ BHN work-hardened | Heavier sections, improved toughness |
| ASTM A128 Grade C | 1.05–1.35% C, 11.5–14.0% Mn, 1.5–2.5% Cr | 220–250 BHN as-cast | Where extra initial hardness is needed |
| Low-alloy martensitic steel | 0.3–0.5% C, Cr-Ni-Mo alloyed | 45–52 HRC | Mixed impact and abrasion |
Composition ranges are quoted against the published standard. Actual analysis for your heat is issued with the castings.
Gallery
From our works
-
Grate sections: opening pattern cast to the customer product spec. -
Anvils and rotor caps after machining of the seating faces. -
Export packing: palletised, strapped and heat-number marked.
Questions
Shredder Grates & Grids: common questions
How does grate wear affect shredder output?
As the openings enlarge, oversize material passes through and product size drifts upward. That loads the downstream separation equipment and can push material out of specification well before the grate looks worn out, so grates are often changed on product size rather than on visible wear.
Can you change the opening size from the original design?
Yes. If you want to shift product size, we can cast grates with a different opening pattern. It is worth modelling the effect on throughput before committing, since smaller openings mean more time in the mill.
What is the largest grate you can cast in one piece?
Our piece weight range runs to 2,000 kg, which covers most single-piece shredder grates. Above that we would discuss a sectioned design.
More from our range
Related products
Enquiry
Enquire about shredder grates & grids
Tell us the machine, the feed and the quantity. If you have a drawing or photographs of the worn part, mention it and we will send an upload link.
Melco Castings is an independent manufacturer of replacement wear parts. Machine and OEM names are used only to identify the equipment our castings fit. We are not affiliated with, endorsed by, or a distributor for any of these manufacturers.