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There are three types of cooling in plastic extrusion molding

Update:04-08-2020
Summary:

There are many plastic products factories that need to […]

There are many plastic products factories that need to use chillers to cool the machines, but when many friends buy industrial chillers, they often don’t know what type of chillers to use to achieve the cooling effect they require, or say no Know what kind of machine is more suitable for your production workshop.

Injection molding machine chillers are generally divided into screw cooling, body cooling, and product cooling

 

1. Cooling of the screw

The role of screw cooling is 1 friction overheating, stabilizing the extrusion pressure of the plastic, promoting uniform mixing of the plastic, and plasticizing quality. But its use 1 is appropriate, especially not excessive, otherwise the plastic melt in the barrel will suddenly cool down, which will cause serious accidents. The screw cooling is prohibited before extrusion, otherwise it will lead to serious equipment accidents.

 

2. Cooling of the body

The function of the body cooling is to increase the heat dissipation of the barrel to overcome the temperature rise caused by frictional overheating, because this temperature rise cannot be stopped during the plastic extrusion process, even after the heating power is cut off, so that the reasonable temperature cannot be maintained for a long time. Maintain, increase heat dissipation, and cool down the barrel to maintain the heat balance during the extrusion process. The airframe cooling is carried out in sections, mainly fan cooling. Considering the different functions of each section of the airframe, special attention should be paid to the use of cooling in the homogenization section.

3. Product cooling

The plastic agent coating should be cooled immediately after leaving the machine head, otherwise it will deform under the action of gravity. Regarding non-crystalline materials such as polyethylene, the problem of crystallization can be ignored. Plastic products can be quenched and cooled directly with water so that they can be completely cooled in the cooling water tank without deformation. The cooling of clean polymers such as polyethylene and polypropylene should take into account the crystallization problem. If the rapid cooling method is used, it will adversely affect the structure of the plastic product and cause internal stress, which will cause the product to produce long cracks in the future. One of the reasons for this is 1 attach importance to the extrusion process; the agent coating of crystalline plastics such as polyethylene and polypropylene should be carried out with a gradual cooling method of warm water. Generally, it depends on the auxiliary equipment of the equipment. The cooling water tank should The water temperature can be divided into sections, starting from the temperature of 75 degrees Celsius-85 degrees Celsius when the plastic agent coating enters the section water tank, and gradually reduce the water temperature until it reaches room temperature. The smaller the temperature difference of each section, the more reasonable.

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