Vacuum Pump Application (1) - Plastic Industry

As an important industrial equipment, vacuum pump has very wide applications. For example plastic & rubber machinery, medical & pharmaceutical industry, food & beverage industry, packaging industry, printing industry, textile industry, woodworking industry, chemical & petrochemical industry, electric power plant, metallurgy, mining, environmental protection industry, etc.

This article mainly tells how vacuum pump is used for plastic and rubber machinery.

Plastic Industry 

Plastic extruder degassing

Vacuum calibrator

EPS foaming machine

Drying of plastic granulate

Pneumatic conveying device

Vinyl chloride gas extraction and compression

Degassing, drying, transferring

Application Machine

Plastic pipe extrusion production line

Profile & Wood plastic extrusion production line

Plastic sheet extrusion production line

Plastic modification

Foam plastic automatic machine

Foam plastic plate machine

Double wall corrugated pipe production line

Double wall winding pipe production line

Breathable film production line

Plastic extruder degassing

During processing, the thermoplastic is melted in the extruder and degassed in the extruder thread part. Vacuum pumps are used to extract gas and vapor components. All low molecular weight materials are extracted to obtain the most ideal thermoplastic quality with smooth shape, higher strength, better insulation performance and lower gas generation rate.

Vacuum calibrator 

The plastic materials melted and degassed within the extruder machine enters a continuous profile on the shaping table. Typically these sections are within pipes, or various technical sections such as windows, wire trunking, and medical pipes. The plastic material is pumped into the mold. For cooling and lubrication, a water film is formed between the inside of the mold and the continuous workpiece, and the air is steadily evacuated by a vacuum pump.

EPS foaming machine

In the production of EPS parts and modules, droplets of pre-expanded polystyrene are blown into the mold using side channel blowers, which are then pressurized with steam. Finally it is polymerized and "baked" into molded articles. In order to avoid deformation during this process, a vacuum pump is used on these parts to ensure that they do not deform and that the moisture in them is quickly evaporated. The heat generated during the evaporation process is removed from the workpiece, speeding up the cooling process.

Drying of plastic granulate

A pneumatic conveyor is used to transfer the pellet material to a dryer before it enters the extruder machine for further processing. The dryer is a closed system with hot air circulation. The air inside the dryer absorbs moisture from the spherical material and expels it through the desiccant. The desiccant itself must be blown with hot air so that it can be reused.

Pneumatic conveying device 

At various stages of production, plastic pellets must be moved from one location to another (eg from storage tank to dryer). This can be done automatically and speed up by using pneumatic conveying devices. The pipeline is routed from the starting point to the end point and connected to the vacuum pump or compressor.

As materials are transported, the air in the pipes is "loaded" - comparable to that of a hurricane, which, depending on the wind speed, can stir up leaves, or have the intensity of a typhoon and even lift the roof off a house. Depending on cargo weight and pipeline length, the system can be designed so that the vacuum pump or compressor generates sufficient speed to pick up the material and deliver it to its destination without leaving it behind in the pipeline .

Since the pneumatic conveyors used to transfer plastic pellets generate large amounts of dust, a filtration system is recommended.

Vinyl chloride gas extraction and compression

During the production of PVC, vinyl chloride gas is polymerized under pressure in an automatic autoclave to form polymerized PVC. At the same time, the gas produced is extracted, compressed and liquefied.