STS Mc¹¹ Two-stage Compounder

Want to find out more about this product?

Get in touch

Two-stage compounder for the production of cable compounds

Top quality PVC, cables and special compounds can only be processed economically with reliable compounding and pelletizing technology. For the Non-European market Coperion has designed a STS Mc11 two-stage compounding system specifically for the production of temperature and shear sensitive plastics. This two-stage processing system with the STS Mc11 twin screw extruder and a single discharge screw ensures both high product quality and maximum economic efficiency in the processing of PVC, cables and special compounds.

Thanks to Coperion’s high standard manufacturing know-how this two-stage compounding system ensures consistency and repeatability of product quality, high throughput rates, more rentability and flexibility.


  • Excellent feeding properties, even for difficult to feed ­powders and hot premixes
  • Gentle product handling, especially in the pressure build-up zone before the die plate
  • Short, defined residence time
  • Uniform product flow through the die plate
  • Precise temperature control
  • Low specific energy input
  • Effective degassing
  • Easily adaptable to new requirements
  • Fast, convenient cleaning
  • Wide range of application

Related Industries

  • Plastics


Soft PVC

  • PVC cables: insulation material, sheathing and bedding compounds
  • Materials for shoes and shoe soles (also PVC-P with foaming agent)
  • Materials for the extrusion of profiles and hoses (including medical applications)
  • Injection molding compounds
  • Calendered films and sheets for flooring

Rigid PVC

  • Materials for the extrusion of profiles for interior and exterior uses
  • Injection molding grades for fittings, etc.
  • Blow molding grades for bottles, containers, etc.
  • Alloys and blends
  • Films (calender feeding)

Crosslinkable polyethylene

  • PEX pipe material
  • Silane crosslinking cable compounds for low voltage applications
  • Peroxide crosslinking cable compounds for middle and low voltage applications

Special compounds

  • Halogen-free, self-extinguishing formulations for cables (HFFR)
  • Elastomer-based compounds for low, medium and high voltage cables
  • Crosslinkable PE (incorporating peroxide)

Principle of the STS two-stage compounder

Coperion twin screw extruder STS working principle
  1. Feeding
  2. Plasticizing, mixing and homogenizing in the twin screw process section
  3. Open, pressureless product transfer into the single screw with the possibility of degassing
  4. Gentle discharge through single screw
  5. Air-cooling pelletizing or eccentric pelletizing – optionally available with other pelletizing methods

Technical data

STS Mc11 Two-Stage 35/120 50/150 65/180 75/200 96/250
Screw diameter twin screw (mm) 36 51 62 71 94
Screw diameter single screw (mm) 120 150 180 200 250
Motor power twin screw (kW) 40 110 210 322 708
Motor power single screw (kW) 22 37 55 75 110
Screw speed twin screw max. (rpm) 600 600 600 600 600
Screw speed single screw max. (rpm) 75 75 75 75 75
Max. throughput (kg/h) - HFFR 35-85 100-260 200-480 300-700 630-1,450
Max. throughput (kg/h) - PVC-P 105-200 310-600 590-1,000 900-1,800 1,850-3,460
Max. throughput (kg/h) - PVC-U 50-105 150-320 300-700 450-1,050 950-2,200
Max. throughput (kg/h) - XLPE (DCP) low/medium voltage cables 35-100 100-300 220-600 300-1,000 700-1,700
Max. throughput (kg/h) - XLPE (DCP) low voltage cables 35-85 100-250 220-500 330-700 700-1,500


Subscribe to the Coperion Newsletter