Composition of plastic extrusion machine

     The main machine of a plastic extrusion machine is an extruder, which is composed of an extrusion system, a transmission system and a heating and cooling system.

Extrusion system

     The extrusion system includes a screw, a barrel, a hopper, a head, and a die. The plastic is plasticized into a uniform melt through the extrusion system, and is continuously extruded by the screw under the pressure established in the process.

Screw: It is the most important part of the extruder. It is directly related to the application range and productivity of the extruder. It is made of high strength and corrosion resistant alloy steel.

Barrel: It is a metal cylinder, which is generally made of alloy steel or composite steel pipe lined with alloy steel that is heat-resistant, high compressive strength, strong, wear-resistant and corrosion-resistant. The barrel cooperates with the screw to achieve the crushing, softening, melting, plasticizing, venting and compacting of the plastic, and continuously and uniformly conveys the rubber to the molding system. Generally, the length of the barrel is 15 to 30 times its diameter. The principle is to make the plastic fully heated and fully plasticized.

Hopper: The bottom of the hopper is equipped with a cutting device to adjust and cut off the material flow. The side of the hopper is equipped with a sight hole and a calibration metering device.

Machine head and die: The machine head is composed of an alloy steel inner sleeve and a carbon steel outer cover. The machine head is equipped with a forming die. The function of the machine head is to convert the plastic melt that rotates into parallel and linear movement, which is evenly and smoothly introduced.

In the mold sleeve, the plastic is given the necessary forming pressure. The plastic is plasticized and compacted in the barrel, and passes through the porous filter plate along a certain flow path through the neck of the head and flows into the head forming mold. The core mold sleeve is properly matched to form a circular gap with a decreasing cross-section, so that the plastic melt is in the A continuous and dense tubular coating is formed around the core wire.

     In order to ensure that the plastic flow path in the machine head is reasonable and eliminate the dead angle of the accumulated plastic, a shunt sleeve is often installed. In order to eliminate the pressure fluctuation when the plastic is extruded, there is also a pressure equalizing ring. The head is also equipped with a mold correction and adjustment device, which is convenient for adjusting and correcting the concentricity of the mold core and the mold sleeve.

     The extruder divides the machine head into a beveled machine head (with an included angle of 120o) and a right-angle machine head according to the angle between the head material flow direction and the centerline of the screw. The shell of the machine head is fixed to the fuselage with bolts. The die in the machine head has a core seat and is fixed to the wire inlet port of the head with a nut. The front of the core seat is equipped with the core, the core and the core seat. There is a hole in the center for passing the core wire. There is a pressure equalizing ring on the front of the machine head for equalizing pressure. The extrusion molding part is composed of a die sleeve and a die sleeve. The position of the die sleeve can be adjusted by the bolt through the support In order to adjust the relative position of the mold sleeve to the mold core, it is easy to adjust the uniformity of the thickness of the cladding layer. The head is equipped with a heating device and a temperature measuring device.

Model	Extuder Type	Products Thickness(Mm)	Max. Output
3 Extruders Co-Extrusion	JWS75+JWS130+JWS75	0.18-0.4	750-850kg/H
5 Extruders Co-Extrusion	JWS65+JWS65+JWS120+JWS65+JWS65	0.18-0.4	800-900kg/H