Application · Plastic Masterbatch
Filler Masterbatch Line: 85–90% CaCO3 at 350–550 kg/h
Filler masterbatch is sold by the tonne, so the line is judged on two numbers only: how much powder it can swallow, and whether the pellets still feed cleanly in the customer's film line. Both are decided before the extruder. A reference filler masterbatch line page from Kerke.
Quick answer
A filler masterbatch line for PE/PP with CaCO3 or talc runs at 80–90% filler loading on a co-rotating twin screw with L/D 48–52, or on a two-stage KTE/SE line above 85%. Output ranges from 100 to 1,500 kg/h depending on screw diameter and filler grade.
Workshop photos and a running video — shot on our own lines, not stock images.
What sets the limit
Pre-mixed CaCO3 and PE carrier are fed by gravimetric feeder into the first barrel, compounded under high shear with a dispersive mixing block, devolatilized under vacuum at barrel 6–8, then pelletized. Above 85% filling the melt viscosity rises sharply — a two-stage line (twin screw compounding + single screw discharge) holds output stable and protects the gearbox.
| Parameter | Value / range |
|---|---|
| Filler loading | 80–90% CaCO3 / talc (85%+ needs two-stage) |
| Screw L/D | 48–52 (custom 28–60) |
| Barrel temperature | 160–200 °C, die 175–190 °C |
| Pelletizing | Water ring hot die-face or air-cooled strand |
| Output (reference) | 100–1,500 kg/h |
| Recommended model | KTE-65B / KTE-75B; KTE/SE-75/180 above 85% |
Output figures are measured on the reference material stated above. Filler grade, bulk density and moisture move output by ±15% — that is why every quotation we issue is tied to a trial report.
Process flow, step by step
- FeedingLoss-in-weight dosing of polymer and filler; side feeder or liquid injection where the formulation needs it.
- Melting and dispersingScrew geometry with 45°/90° kneading blocks; barrel profile 160–200 °C, die 175–190 °C.
- DevolatilizationVacuum vent at −0.06 to −0.09 MPa removes moisture and volatiles before the die.
- Pressure build-upThrottle or discharge section stabilises die pressure; a melt pump where gauge control matters.
- Pelletizing and packingWater ring hot die-face or air-cooled strand; then centrifugal dryer, vibrating screen and bagging.
Equipment configuration
| Stage | Equipment | Why this choice |
|---|---|---|
| Main machine | Co-Rotating Twin Screw Extruder | Architecture follows the filling level and the mixing duty, not the required tonnage. |
| Screw geometry | Building-block elements, W6Mo5Cr4V2, bimetallic liner | Wear package for abrasive filler; mixing blocks only where dispersion demands them. |
| Feeding | Loss-in-weight feeder, side feeder where needed | Recipe accuracy: ±0.5% short term on the weighed component. |
| Pelletizing | Pelletizing system | Chosen by polymer and filler ceiling — water contact is the deciding column. |
| Downstream | Centrifugal dryer, vibrating screen, bagging | Fines below 2% and moisture below the specification of your downstream process. |
Output by model
| Model | Dia. (mm) | Speed (rpm) | Motor (kW) | Torque (N·m) | Output (kg/h) |
|---|---|---|---|---|---|
| KTE-50B | 50.5 | 500–600 | 55–75 | 2×525 | 80–200 |
| KTE-50D | 50.5 | 300–800 | 75–90 | 2×860 | 100–300 |
| KTE-52B | 51.4 | 500–600 | 55–75 | 2×720 | 80–200 |
| KTE-52D | 51.4 | 500–600 | 75–110 | 2×1050 | 100–400 |
| KTE-65B | 62.4 | 500–600 | 90–110 | 2×860 | 200–450 |
| KTE-65D | 62.4 | 300–800 | 132–160 | 2×1530 | 350–600 |
| KTE-75B | 71 | 500–600 | 132–160 | 2×1530 | 300–800 |
| KTE-75D | 71 | 300–800 | 200–315 | 2×2100 | 500–1000 |
| KTE-85B | 85 | 500–600 | 220–315 | 2×2100 | 550–1000 |
| KTE-95B | 93 | 500–600 | 250–315 | 2×3000 | 800–1500 |
| KTE-95D | 93 | 500–800 | 315–500 | 2×4800 | 1000–2000 |
| KTE-135B | 135 | 500–600 | 315–500 | 2×4800 | 1500–3000 |
| KTE-135D | 135 | 500–800 | 500–1000 | 2×7800 | 1500–4000 |
Three mistakes that cost the most
1. Sizing by motor kW instead of torque
Sizing by motor kW instead of torque — a 90 kW B-type gearbox cannot push 88% filling; the result is unmelted filler and a burnt screw.
2. Skipping the bimetallic liner
Skipping the bimetallic liner — CaCO3 at 85% wears a standard barrel out in 12–18 months.
3. Undersized cooling tower: water ring pelletizing at 1,000 kg/h needs 15–20 °C water; warm
Undersized cooling tower: water ring pelletizing at 1,000 kg/h needs 15–20 °C water; warm water means stringy, agglomerated pellets.
FAQ
What is the maximum CaCO3 loading?
85–90% is achievable with a two-stage line and a bimetallic-lined barrel. Above 88% the melt becomes abrasive paste; output drops and screw life shortens, so we quote a trial run before committing to a number.
Can one line run both 80% and 88% filling?
Yes, with a two-stage configuration and a screw configuration change. A single-stage twin screw sized for 80% will not hold 88% at rated output.
How long does a material trial take?
3–7 days for standard filler grades. Send 25–50 kg of your CaCO3 and carrier resin; we return pellets, a running video and a capacity report.
What output can you guarantee for this application?
The reference band is 100–1,500 kg/h, measured on the stated material. We quote a guaranteed figure only after a trial on your own material, because filler grade, bulk density and moisture move output by ±15%.
Can we run our material before ordering?
Yes — send 25–50 kg. We return pellets, a running video and a report with temperatures, screw speed, feeder settings and output per hour. The trial is free; you cover the freight.
What is the delivery time?
30–45 working days for standard configurations, 45–70 for custom screw geometry and ODM work. Voltage and frequency are built for the destination country.
Where these numbers come from
Parameters are taken from the Kerke product parameter table and the product master data sheet, and cross-checked against commissioning records for lines in the same application. Formulations and temperature windows are typical industry values, not a recommendation for your specific compound — every figure marked reference must be confirmed on a material trial before it becomes a contractual number.
Reviewed by the Kerke process team, Nanjing. Page updated 6 November 2026.
Send 25–50 kg and we run it on our lab extruder: pellets, running video and a capacity report back in 3–7 days.
Filler masterbatch line — the short version
Note on filler masterbatch line: the numbers above are reference ranges from Kerke's own trial runs, not catalogue promises. Screw geometry, wear package and pelletizing method are set on the trial bench first, so the output you compare is the output you get. If your grade is not in the tables, send it — the closest configuration is usually a change of screw set, not a different machine.
Related on this site: Machine range: KTE-50B to 135D · Pelletizing methods compared · quotation and free trial · Wikipedia: Masterbatch






