Plastic Pelletizing Machine for Rigid Regrind and Film

A granulator cuts plastic mechanically against a screen and produces flake of roughly 8 to 16 mm. A pelletizer melts that flake, filters the melt and cuts it into pellets of about 3 mm. One is a cutting machine, the other is an extrusion machine, and in a full line the granulator comes first.

For film at any real volume, yes. Film is too light to feed itself into a screw and bridges at the throat, and a forced feeder does not fix a density problem. That is why the ML family exists, with compactor volumes from 300 to 1,500 litres. The exception is small in-house scrap volumes, where the LTG mini pelletizer is a better fit than either.

Two stages give better degassing and better filtration, at a higher capital and power cost. They earn their keep on printed film, on material that has already been recycled once, and where your buyer specifies a tight pellet quality. On clean washed regrind a single stage is usually sufficient and cheaper to run.

Below 1 percent for rigid flake, and that is achievable with centrifugal dewatering plus hot-air drying. Film is harder because it holds water in its folds, which is why film lines use a squeezer. Wet feed becomes steam in the barrel and bubbles in the pellet, and no extruder setting compensates for it.

No. The LTG series is for clean PE film only, and we would rather tell you that before the order than after it. Dirty film needs a washing line first and then an ML with a compactor. Running dirty film on a mini pelletizer produces poor pellets and blocks filters constantly.

Water-ring is more compact and suits most recycled material well. Strand cutting gives more control over pellet geometry and is the choice when your buyer specifies pellet dimensions. Both are available on our SJ and ML lines, so the decision can wait until we know who buys your pellets.

Installed power runs from 175 kW on the smallest SJ up to 565 kW on the largest, and 205 to 700 kW across the ML range. The LTG mini pelletizers are a different scale entirely, with extruder motors of 15, 37 and 55 kW. Installed power is not the same as consumption, but on a pelletizing line electricity is the dominant running cost either way.

Not well, and the reason is feeding rather than melting. A machine set up for dense regrind bridges on film, and a compactor-fed machine is more equipment than rigid regrind needs. If you genuinely process both, it is usually cheaper to run two correctly matched lines than one compromised one.

It depends on what washing left behind and what the buyer will accept. Well-washed rigid flake often runs on a plate or hydraulic screen changer with a 60 to 100 mesh screen. Film with paper fibre or fine sand needs a continuous or backflush changer, because manual screen swaps will otherwise stop the line several times per shift. Choose by downtime per shift rather than by machine price.

Almost always moisture. Flake entering the extruder above roughly 2% water turns to steam in the barrel and leaves voids in the strand. The fix is upstream, not in the extruder: check the dryer, check whether film is carrying water in its folds, and consider a squeezer before drying. Degassing on the screw helps, but it compensates for a drying problem rather than solving it.

Recycled pellet from a well-run line is usable in most non-critical applications, but it is not identical to virgin. Melt index shifts with each heat history, colour drifts towards grey or the dominant input colour, and mechanical properties drop slightly. Most converters blend it with virgin at a ratio their part can tolerate. The realistic goal is consistency batch to batch, which is what buyers actually pay for.

We manufacture screws and barrels for our own machines and can quote replacements for other makes when you provide the drawing or the original dimensions: diameter, L/D ratio, flight geometry and material specification. What we do not do is reverse-engineer a worn screw from a photograph, because the wear pattern is exactly the information that has been lost.

Clean, dry plastic flake is fed into an extruder, melted at controlled temperature, pushed through a filter screen that catches remaining contamination, and cut into uniform pellets by a water-ring, strand or underwater cutter. The step that decides success is upstream: flake above roughly 2% moisture will steam in the barrel and leave voids, and contamination that washing missed becomes screen changes rather than pellet.

Pyrolysis breaks plastic back into oil and is aimed at mixed or degraded waste that mechanical recycling cannot handle. It needs far higher capital, energy input and permitting than an extrusion line, and the output is a feedstock rather than a resin you can sell to a converter. For sorted single-polymer streams, mechanical pelletizing gives a usable product at a fraction of the cost, which is why it remains the default route.