Horizontal Twin Screw Extruder Machine , Conical Twin Screw Extruder

Product Specification

                                                    SJSZ Series Plastic Conic Double Screw Extruder Machine

SJSZ Series Plastic Conic Double Screw Extruder Machine is widely used for plastic pipe extrusion line ,plastic profile extrusion line and plastic sheet extrusion machine line. It is used for feeding,transporting, plasticing,melting plastic material and make sure that plastic material out from different extrusion moulds.

SJSZ Series Plastic Conic Double Screw Extruder Machine  is composed of driven motor, gear reducer box, screw and barrel, feeder, casting aluminum heater, cooling blower, vacuum pump, hopper and control cabinet.

Driven motor: It is main part of PVC pipe conic double screw extruder. We'd better choose good brand AC type driven motor matching with inverter controll for saving power running cost.

Gear recuder box: It is used for connecting motor and screw . As we know that motor rotating speed is very high , if we connnect motor and screw directly, screw rotating speed will be too fast, mixed PVC resin material will be not melting and plasticing inside of barrel. So we choose gear reducer box for connecting motor and screw for reducing rotating speed of screw through size and teeth of gear changing in the gear box.

Screw and barrel: It is most important part of conic double screw extruder. Quality of PVC pipes main depends on this part. In normal, the surface of screw should be paint double alloy for anti-wear due to mixed PVC resin material including high percent of calcium carbonates. At the same time, the design of screw structure is a key point for extrusion capacity and quality, now design of screw is becoming standardization and homogenization on the market, quality of screws are stable for most suppliers now.

Feeder: It is used for feeding mixed PVC resin material into barrel from the hopper on the top of extruder. This device is developing from single screw feeding to parallel screw feeding process. Now more and more PVC pipe making machine manufacturers adopt parallel screw feeding device for avoding mixed PVC resin crack-bridging while material transported into barrel on the bottom of hopper.

Casting aluminum heater: It is used for heating barrel and screw which ensure mixed PVC resin material can be plasticizing and melting under the suitable temperature when mixed PVC resin material comes into inside of barrel and transported forward by screw.

Cooling blower : It is used for cooling barrel and screw. Due to casiting aluminum heater is keeping heating, temperature of screw and barrel will be increasing and if it excess setting temperature, cooling blowers will be started to work for cooling barrel which avoid PVC material resolved in the inside of barrel due to temperature is too high.

Vaccum pump : It is used for sucking the moisture of the mixed PVC resin material which is under suitable temperature from the barrel in order to make sure getting the final PVC pipes better quality.

Hopper : It is used for keep the mixed PVC resin material in the silo and make sure material can be into barrel continuously. It is like a material transport station.

Control Cabinet: It is used for control whole cornic double screw extruder running by switchs or PLC programes according to different circuits control required.

What's the advantages of twin screw extruder over single screw extruder ?

• Pumping efficiency is better and less dependent on the flow properties of the material.
• Mixing is more efficient.
• The heat exchange rate from the barrel surface to the material is faster and more uniform.
• Residence time is more uniformly distributed.
• Thanks to the possibility of flexible modular configuration of the screw and the barrel, the twin-screw extruder is a more versatile machine.
• High moisture and sticky materials can be handled. This is probably the most important advantage, because it enables processing of materials that could not be handled hitherto by single-screw extruders. The introduction of twin-screw technology has resulted in a significant expansion of the application of extrusion to foods and the spectrum of extruded products.
• Self-wiping reduces the risk of residue build-up.
• Feeding problems with cohesive materials are less serious.

On the negative side, the relative disadvantages of the twin-screw extruder are:

• Higher cost: both capital expenditure and the operating costs are higher.
• Complexity: the twin-screw extruder is mechanically more complex and less robust; consequently, the machine is more sensitive to mechanical abuse (such as high torque).