News Time2016.05.21 News Sources Views
Plastic granulator host is extruding machine composed of extrusion system, transmission system and heating cooling system. Its aim is to develop the renewable resources and to turn waste into treasure.
1.squeezing extrusion system includes hopper and handpiece. plastic plastifies into homogeneous melt by extrusion system, and is extruded continuously by screw under pressure in this process.
(1) Screw: is the main part of extruding machine. It is directly related to the application range and productivity, Screw is made of high strength and corrosion resistance of alloy steel.
(2) Barrel: is a metal cylinder, generally made of heat resistant, high crushing strength, strong wear resistance, corrosion resistance of alloy steel or composite pipe of lining alloy steel . Barrel and screw can implement plastic crushing, softening and melting, plasticizing, exhausting and compacting, and convey rubber to molding system continuously. Generally, barrel length is 15 ~ 30 times than its diameter to make heating and fully plastifying fully.
(3) Hopper: is equipped with cutting device at the bottom of the hopper to adjust and cut the flow of material. The side of the hopper is equipped with sight hole and measuring calibration.
(4) Handpiece and mould: handpiece consists of alloy steel inner sleeve and carbon steel jacket, with molding inside. Its function is to turn the movement of plastic melt into a parallel straight line. Importing to the die sleeve steadily, which gives necessary forming pressure. Plastic plasticized and compacted in the barrel, forms die by the flow of porous filter plate along a certain head neck into the head , and mold core matches up die sleeve appropriately to form decreasing annular space. This can make the plastic melt around the conductor to form a continuous solid tubular cladding layer. In order to ensure that the nose in plastic flow is reasonable, a split sleeve is placed to eliminate accumulated plastic corner. A set of equalizing ring is also placed to eliminate the plastics extrusion pressure fluctuations. The nose is also equipped with mold correction and adjustment device, easy to adjust concentricity between mold core and mold sleeve .
2. Rotation system is used to run a screw driver, and supply screw needs torque and rotational speed in the extruding process, usually composed of motor, reducer and bearing, etc.
3. Lubricator and cooler heating and cooling is necessary for plastic extrusion process.
(1) Extruding machine is electrical heating in 2013. It is usually divided into resistance heating and induction heating. Heating tablets are installed in the fuselage, machine neck, in all parts of the nose. Heating device heats the plastic inside the barrel from outside rising temperature to achieve the required temperature of the process.
(2) Cooling device is used to ensure that the plastic in the required temperature range. Specifically, it contributes to rule out excessive heat generated by the shear friction with the screw rotating, so it is helpful to plastic decomposition, charred and finalize the design with appropriate temperature. Barrel cooling has two kinds, water and air cooling. general small and medium-sized squeeze molding machine adopts air cooling, and the large one mostly uses water or the combination of two forms. Screw cooling mainly adopts center water cooling for the purpose of increasing the rate of conveying solid materials, stabilizing the quantity of adhesive, and improving the quality of products. But the cooling in the hopper is to strengthen the transport of solid materials and to prevent sticky plastic grains from jamming because of temperature rise.
