Rotary vane vacuum pump is a common thermoforming method in the production of plastic packaging containers. It is widely used in the processing of packaging materials. Vacuum suction moulding is generally used to make open shell products of thermoplastic sheets. The principle is simply to heat the plastic sheets to a certain temperature, soften them to viscoelastic state, and then vacuum the mold through rotary vane vacuum pump suction. The pressure difference forms vacuum suction, so that the sheets are deformed and then covered on the contour surface of the mold. Finally, after cooling, shaping and dressing.
What is the vacuum plastic suction unit?
The whole vacuum suction unit is generally composed of upper and lower heaters, temperature controllers, bearing plates, pressing frames, rotary vane vacuum pumps, vacuum chambers, mould temperature controllers, cooling devices, etc. The parameters are controlled by computer storage, and the control is simple. When a certain type of product is produced, only the corresponding parameters can be adjusted.
Vacuum plastic forming relies on the vacuum pressure difference to make the sheet stretch and deform. At present, the vacuum is easy to realize, master and control, which makes the vacuum suction molding products have the advantages of low price and high production efficiency, and has been widely used. Its form can be divided into three types: die less molding, punch (Yang Mo) forming and die (die) molding.
Vacuum mouldless forming is that the sheet is heated to the required temperature, pressed on the clamping ring, and then vacuum pumped. By controlling the vacuum degree, the sheet reaches the required forming depth. In this method, the parts do not touch any die surface, the surface gloss of the parts is high, and there are no defects. However, during the forming process, the drawing degree and the outline shape of the parts can only be changed, and the parts with complex shape can not be formed.
The difference between punch (positive) forming and concave (negative) forming is that the contact surface between the forming material and the forming die is different. The products formed by them are of high quality on one side of the cavity wall, and the structure is more distinct and meticulous. But the punch forming is more advantageous for the manufacture of products with larger wall thickness and depth, while the die is not suitable for the production of products with large depth. At the same time, they have their own characteristics in both internal and external dimensional accuracy and product thickness. The inner dimension of the product is accurate, the largest part of the wall thickness is at the top of the punch, the thinnest part is at the junction between the side and the bottom of the punch, the outer dimension of the product is accurate, the largest part of the wall thickness is at the bottom of the cavity, the thinnest part is at the junction between the side and the bottom of the cavity, and with the increase of the depth of the cavity, The wall at the bottom of the product becomes thinner.
Rotary vane vacuum pump design features:
1. The overall design of the rotary vane vacuum pump
The rotary vane pump motor and pump are integrated and designed to make the pump more compact and lightweight.
2. The design of the rotary vane vacuum pump
The motor casing of the vacuum pump adopts aluminum alloy material, and the aluminum alloy has high heat dissipation efficiency, ensuring continuous normal operation for a long time and having a good appearance.
3. The internal design of the rotary vane vacuum pump
The fuel tank of the rotary vane pump is treated as a partition, and an oil and gas separation device is arranged on the exhaust gas, so that no fuel injection and oil mist pollution are reduced.
4. Return oil design of rotary vane vacuum pump
In order to avoid the return of the vacuum pump, the rotary vane pump is specially designed in the intake air passage to prevent the pump oil from flowing back after the pump is stopped and contaminating the evacuated air pump and the pipeline.
With the continuous expansion of vacuum technology in various application fields, the demand for rotary vane vacuum pumps is increasing, especially for vacuum blow molding of rotary vane vacuum pumps.