EPDM电线料造粒机-玖德隆机械（昆山）有限公司

1. Extruder parameters, extruder parameters: Screw diameter (): screw outer diameter, commonly used ~, as the diameter increases, the extruder's conveying capacity increases and the production capacity increases. Screw aspect ratio/: The ratio of the effective length of the working part to the diameter, usually ~, with a large aspect ratio, uniform mixing, and reduced backflow and leakage. Long plasticization time is required, such as hard plastics, powdery plastics or crystalline plastics, and the aspect ratio is required to be large. Heat-sensitive plastic is easily decomposed by heat and has a small length-to-diameter ratio. When the groove depth is small, higher shear force is generated, which is beneficial to plasticization, but the extrusion productivity is reduced. is larger, the opposite is true. changes along the screw axis. Helix angle: The angle between the thread and the screw cross section increases, the production capacity increases and the shearing effect decreases. Between ~ degrees. Thread edge width: If it is too small, leakage will increase and output will decrease
2. Extruder structure, extruder structure
Structural diagram of single-screw extruder - motor - reduction device - cooling water inlet - Cooling water jacket - hopper - thermometer - heating jacket - screw - filter - porous plate - machine head and die - base transmission device consists of motor, reduction mechanism and bearings. It has the function of ensuring constant screw speed during the extrusion process. The stability of product quality and the ability to change speed are guaranteed. Feeding device: Regardless of whether the raw materials are granular, powdery or flaky, the feeding device adopts a feeding hopper. There should be devices in the feeding hopper to cut off the material flow, calibrate the material amount and remove the remaining material. Barrel The barrel is one of the main devices of the extruder, in which the mixing, plasticizing and pressurizing processes of plastics are carried out. The pressure inside the barrel can reach up to 100% during extrusion, and the working temperature is generally ~, so the barrel is a pressured and heated container, usually made of high-strength, tough, wear-resistant and corrosion-resistant alloy steel. The outside of the barrel is equipped with zoned heating and cooling devices, and each is equipped with thermocouples and automatic instruments. Screw The screw is a key component of the extruder. The structure of the general screw is as shown in the figure. Die and machine head: The machine head is the transition part between the die and the material. Its length and shape depend on the type of plastic used, the shape and heating method of the product, and the size and type of the extruder. The quality of the machine head and die structure has a great impact on the output and quality of the product, and its size is determined based on rheology and practical experience. Cooling device: Cool the molten material into solid (or product) for easy cutting into granules or products. Post-processing of coiling (cutting): spraying, silk screen printing, surface treatment, etc.
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