Extruders & Compounding Machines

STS Mc¹¹ Compounder

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Compounders for considerable increases in throughput

With its specific torque of 11.3 Nm/cm3 STS Mc11 compounders sets standards: it features up to 27% higher throughput rates than the preceding model, while the higher degree of screw fill results in a decrease of melt temperature, thus improving compound quality. It incorporates the full process and quality know-how of Coperion.

The STS Mc11 series is exclusively equipped with European, Coperion branded gearboxes. Maximum screw speed has been increased from 800 to 900 min-1. To improve cleaning and facilitate quick changeovers for masterbatch applications, the STS twin screw extruder also features optimized hoppers with inserts and a redesigned die head. The screw shaft coupling is similar to the one long proven in the ZSK Mc18 series. The optimized base frame withstands torsion under maximum stress.

The STS Mc11 compounder covers most standard applications in process technology. It offers high productivity at an attractive price-performance ratio. Production of the STS Mc11 is in Nanjing, China, in compliance with CE directives. The result: A high-performance compounding system with low investment costs which ensures a fast return on investment. The modular design of the process section allows maximum flexibility in production at process lengths of 24 to 68 D.

Read more about the STS Mc11 two-stage compounder


  • Proven Coperion manufacturing standards
  • CE certificate
  • New, optimized base frame to withstand torsion under ­maximum stress
  • Screw speeds of up to 900 min-1 depending on the machine configuration and application
  • Two operation and maintenance friendly machine control concepts – BasicMaster (relay control) and TouchMaster (PLC control)
  • European, Coperion branded, high-performance gearboxes with high-tech safety clutch for safe transmission of high torque
  • Die head with improved heating system and optimized flow geometry
  • 4 D individual barrel with precision single zone tempering
  • High performance brass heater shells and water flash cooling with flexible connection to water manifold for optimal processing conditions in every heating zone
  • Self-wiping, co-rotating screw shafts for fast, easy changes in product and color
  • A variety of materials available for the process section: ­nitrided steel for the basic version, special high-alloy wear-protected steels for demanding processes with a high stress level

Areas of application OF THE STS Mc¹¹ TWIN SCREW COMPOUNDER

  • Filling and reinforcing of engineering plastics
  • Alloying and filling of polyolefins/TPE
  • Coloring of polyolefins and engineering plastics
  • Production of color masterbatch, flame retardant masterbatch, filler masterbatch and additive masterbatch
  • Recycling of regrind plastics, etc.
  • Cable compounds, incl. PVC, HFFR, XLPE
  • Other applications
Coperion STS 75 Mc PLUS Extruder
The STS 75 Mc PLUS twin screw extruder features a specific torque of 13.6 Nm/cm³. For high throughput and improved product quality.


  • 4th generation of STS technology with Coperion Engineering from Germany
  • Specific torque of 13.6 Nm/cm3 for throughput rates of up to 3 t/h
  • Screw speeds of up to 900 min-1 – depending on the machine configuration and application
  • Cold hammered shafts from Coperion Germany
  • Die head and process section with heating cartridges for maximum energy efficiency
  • Coperion’s in-house, high-precision process sections, available in a variety of materials to meet the needs of wear and corrosion protection
  • Excellent self-wiping co-rotating screws, narrower melt residence time distribution curve, highest product quality
  • High-performance gearboxes and safety couplings from European brands
  • Stronger base frame for higher torque, safety and reliability
  • CE compliant

Laboratory extruder STS 25 Mc¹¹

Coperion STS 25 Extruder

Coperion’s STS 25 Mc11 extruder boasts all the advantages of the STS Mc11 series, has a simple design, is operator-friendly and easy to clean. The base frame has a closed, simple to clean surface and is equipped with castors for easy movement of the extruder and fast installation. By having the same screw diameter ratio Do/Di of 1.55 and the same maximum specific torque Md/a³ of 11.3 Nm/cm³ as the whole STS Mc11 extruder series, production parameters of the STS 25 Mc11 can be reliably scaled up to larger STS sizes which makes it the ideal compounding system for recipe development and basic scientific research.

Masterbatch System Featuring an STS 35 Mc¹¹ Twin Screw Extruder

Coperion Doppelschneckenextruder STS Mc11

For the manufacture of superior quality masterbatches with exceptional efficiency and cost-effectiveness, Coperion provides an all-inclusive production system. This comprehensive package incorporates an STS 35 Mc11 twin screw extruder, a Coperion K-Tron S60 volumetric single screw feeder, and an SP 100 EN strand pelletizer from Coperion Pelletizing Technology.

STS 35 Mc¹¹ Twin Screw Extruder

  • Screw diameter of 35 mm [1.38 in]
  • Max. specific torque of 11.3 Nm/m³
  • Do/Di = 1.55 (outer to inner screw diameter) - across the entire STS Mc11 series, identical to Do/Di of the ZSK Mc18 series
  • Throughput rates up to 300 kg/h
  • Main drive, Coperion gearbox, safety coupling and control cabinet from European manufacturers
  • Compact design, dust-free and easy to clean thanks to smooth surfaces
  • Water supply and electrical wiring are integrated and physically separated in the base frame
  • Feed hopper in quick-change design for fast disassembly
  • Self-cleaning, co-rotating twin screws with tight screw profile for fast product and color changes
  • Die head in masterbatch design: easy to clean and features improved heating system and optimized flow geometry
  • Attractive price-performance ratio
  • Short delivery times between 4-5 months
  • Over 350 systems installed worldwide
Coperion K-Tron Feeder S60

 S60 Volumetric Single Screw Coperion K-Tron Feeder

  • Continuous operation for consistent, accurate feeding of ingredients
  • Gentle product handling of the horizontal agitator and feeding screw
  • Interchangeable feeding tools
  • All parts in contact with the product made of stainless steel
  • Fast disassembly and very good cleanability of the feeder
Coperion Strand Pelletizer SP 100

Strand Pelletizer SP 100 EN

  • One-side bearing
  • Working width 100 mm [3.94 in]
  • Up to 20 strands
  • Throughputs up to 650 kg/h - depending on the recipe
  • Easy access for quick cleaning
  • Vibration isolation
  • Many other useful options, such as pellet length regulation, drive for top feed roll, die head cooling, transmission signal to extruder control, customized base frame, etc.

Technical data

STS Mc11 25 35 50 65 75 96 125
Specific torque Md/a³ [Nm/cm³] 11.3 11.3 11.3 11.3 13.6 11.3 11.3
Max. torque per shaft [Nm] 106 305 835 1,590 2,772 5,350 11,600
Max. screw speed [rpm] 1,200 900 900 900 900 600 600
Max. motor power [kW I Hp] 30 I 40 60 I 81 165 I 221 315 I 422 513 I 688 706 I 947 1,700 I 2,280
Max. throughput rate [kg/h I lbs/h] 110 I 243 260 I 573 800 I 1,764 1,400 I 3,086 3,000 I 6,614 4,200 I 9,259 8,000 I 19,030


Additional features

Coperion twin screw extruder STS Mc11 swivel arm

STS side feeder: new design with swivel arm

  • Swivel arm allows easy docking and optimal alignment to adjacent barrels
  • Engineered by Coperion Stuttgart, Germany, equipped with European gearbox, final assembly at Coperion Nanjing, China
  • High torque, deep cut screw channels and Do/Di ~ 2 to achieve high throughput rates
  • High pressure built up to 30 bar
  • High-low speed motor or frequency control motor
  • High manufacturing precision, only 2 mm clearance between side feeder screws and twin screws of STS Mc11
Coperion twin screw extruder STS Feed Hopper

Feed hopper in quick-change design

The feed hopper is simply clamped to the inlet barrel and can be quickly removed by loosening the bolts. The quick-release insert which protects the barrel wall from contamination can then be changed very easily.

Coperion STS Die Head

Quick cleaning die head

  • Simple, quick opening by loosening a few bolts
  • User-friendly assembly due to pivoting arm
  • Insertion of screens possible by using breaker plates
  • Optimized flow geometry with minimal dead space for safe strand discharge, even with highly filled products

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