Plastic Lumps Shredder & Crusher — Purgings, Blocks & Start-Up Lumps

Any solid, thick mass of cooled polymer: barrel purgings from injection molding machines, head drainage and start-up dumps from extruders and blow molders, failed thick-section moldings, tryout blocks, and the mixed lumps that reprocessors buy by the tonne. They share two traits — high material value, since most lumps are single-grade polymer with one heat history, and zero processability on a standard granulator. That combination is exactly what a single shaft lumps shredder exists to solve.

Cutting physics. A granulator’s blades pass at high speed and rely on the material being thin enough to shear in one strike — a dense lump instead delivers a shock load that chips the blade edge or stalls the rotor. The S3-600’s rotor turns at 80 rpm with the full torque of a 22 kW drive behind it, so each of the 26 hardened blade tips removes a small bite per pass and the lump is reduced progressively. Slower speed, higher force, no shock loads — which is also why the machine can run 24 hours continuously.

The side-feeding hopper opening is 600 × 1000 mm with a 650 × 600 mm cutting chamber — sized for the purge blocks a typical molding or extrusion plant produces. Side feeding is the practical advantage: heavy lumps slide in from a trolley at working height instead of being hoisted over the top of the machine. Oversized blocks are occasionally sawn once before feeding. If you are unsure about your largest lumps, send photos with dimensions or bring them for a trial at our works.

The S3-600 produces coarse, irregular shred — big-size lumps reduced to pieces ready for second-stage processing. For most buyers the next step is an RE-series plastic grinder, which cuts the shred against a mesh screen into uniform regrind sized to your specification. Reground, polymer-sorted material commands far better prices than lumps and can be dosed back into your own production at a controlled ratio. If you only need volume reduction for transport or resale to a reprocessor, the shredder alone does the job.

Yes, with realistic expectations. A purging made during a colour change is internally mixed, so its regrind will not match any single colour — such material typically goes into dark-coloured, non-appearance products, inner layers, or is sold as mixed regrind. Purgings of a single known grade are worth much more: keep them segregated from the start and label the bags. Either way the material recovers far more value as regrind than as lump-rate scrap sold from the plant corner.

Every machine is quoted to the job. What moves the number is capacity, throat size, motor rating, MS or SS construction and the automation you add — a blower, a conveyor, a control panel. Our guide to what drives machine cost walks through each of those; send us your material and daily volume and we will size the machine and quote it, usually the same day.

Yes — the S3-600 platform also shreds paper piles, wood logs and FRP waste, so plants with mixed industrial scrap can run one shredder across streams (one material at a time, with a clean-down between them if the output is to be recycled). For dedicated FRP volumes see our FRP waste shredding page. If your waste is mostly hollow containers rather than solid lumps, a different machine may suit better — ask us before you buy.

Yes — and for lumps we strongly recommend it, because density and size vary so much between plants. Bring a representative lot of your purgings to our works at Andheri East, Mumbai; we will shred them, show you the throughput on your material and the shred output, and demonstrate second-stage grinding if you want regrind. Outstation buyers can request a video trial. Book a slot — Mon–Sat, 9 AM to 7 PM.