Application · Cable Compound

PVC Compounding Line: Why Air-Cooling Hot-Face Cutting

PVC is heat-sensitive and water-sensitive at the same time, which rules out both long residence time and water contact. That single sentence decides the whole line: two-stage, hot-face, air-cooled. A reference pvc compounding line page from Kerke.

Updated 6 November 2026

Output 100–1,500 kg/h

Line type Two-stage KTE/SE

Basis parameter table + material trial

PVC Compounding Line — workshop photo 1, Kerke workshop, Nanjing

PVC Compounding Line — workshop photo 2, Kerke workshop, Nanjing

PVC Compounding Line — workshop photo 3, Kerke workshop, Nanjing

PVC Compounding Line — workshop photo 4, Kerke workshop, Nanjing

PVC Compounding Line — workshop photo 5, Kerke workshop, Nanjing

PVC Compounding Line — workshop photo 6, Kerke workshop, Nanjing

Running video — PVC Compounding Line, Kerke workshop

Quick answer

PVC compounding (rigid and flexible, cable and profile grades) runs on a two-stage KTE/SE line with air-cooled hot die-face pelletizing to avoid hydrolysis, at 100–1,500 kg/h. Temperature control, not shear, is the process variable that decides quality.

140–170 °Cbarrel temperature

36screw L/D

100–1,500 kg/hline output

Workshop photos and a running video — shot on our own lines, not stock images.

What sets the limit

PVC powder, plasticizer and stabilizer are mixed in a high-speed mixer, fed to a twin screw for gelling, then discharged by a single screw through a hot die-face cutter with air cooling.

**Table 1.** Key parameters for pvc compounding line. Reference values — confirm on a material trial.
Parameter	Value / range
Materials	Rigid PVC, flexible PVC, cable compound
Pelletizing	Air-cooled hot die-face (prevents hydrolysis)
Output	100–1,500 kg/h
L/D (stage 1)	32–40
Temperature	150–190 °C, tight control
Model	KTE/SE-65/150, KTE/SE-75/180

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 150–190 °C, tight control.
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 packingAir-cooled hot die-face (prevents hydrolysis); then centrifugal dryer, vibrating screen and bagging.

Equipment configuration

**Table 2.** What the line is made of, and why each part is specified that way.
Stage	Equipment	Why this choice
Main machine	Two-Stage Extruder KTE/SE	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

**Table 3.** Two-stage KTE/SE — reference output. Full range on the machine page.
Configuration	Stage 1 (twin screw)	Stage 2 (single screw)	Output (kg/h)	Typical product
KTE-50B / SE-120	50.5 mm	120 mm	300–500	Colour / filler masterbatch
KTE-65B / SE-150	62.4 mm	150 mm	500–800	Filler masterbatch 85%, PVC
KTE-75B / SE-180	71 mm	180 mm	700–1,200	High filler 88–90%, HFFR
KTE-95B / SE-200	93 mm	200 mm	1,000–2,000	High filler, cable compound

Three mistakes that cost the most

1. Water cooling on PVC pellets causes hydrolysis and black specks

Water cooling on PVC pellets causes hydrolysis and black specks — always air-cool.

2. Over-gelling in the twin screw burns the compound; the SE stage should do the pressure bui

Over-gelling in the twin screw burns the compound; the SE stage should do the pressure build, not extra work.

3. Leaving PVC in a hot barrel overnight

Leaving PVC in a hot barrel overnight — heat-sensitive compounds must be purged and cooled below 150 °C before stopping, or the screw seizes on degraded compound.

FAQ

Why two-stage for PVC?

PVC degrades under prolonged high shear. The twin screw gels the compound quickly and the single screw only pressurizes it.

Can you pelletize rigid PVC?

Yes, with a hot die-face cutter and air cooling; the pellet shape is lenticular, which is normal for rigid PVC.

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.

Tell us your material — we will tell you the line

Send 25–50 kg and we run it on our lab extruder: pellets, running video and a capacity report back in 3–7 days.

Get a quote Send material for trial

PVC compounding line — the short version

Note on pvc compounding 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.