Vacuum pumps for plastic extrusion

Plastic. It’s one of the most staple materials in the modern world-capable of being melted, molded, cut, combined, remade and recycled into a thousand different things. As versatile as the material is, the stages of plastic processing are also varied and they all in some way or another depend on the power of vacuum technology. 

Out of all the different stages that plastics and polymers undergo, extrusion is one of the most important. Extrusion is a stage where continuous plastic shapes can be created by melting and forcing the plastic material through an opening or cavity. The equipment that’s used is called an extruder. Plastic extrusion used to produce things like pipes, tubes, sheets and even custom-shaped plastic items. 

• Degassing and Decontamination: Vacuum pumps create a controlled environment within the extruder's hopper or barrel, removing unwanted gases and moisture. This minimizes defects such as porosity, bubbles, and surface imperfections, resulting in higher product quality and consistency.

• Cooling and Solidification: As the extruded plastic profile emerges from the die, it undergoes a critical phase of cooling and solidification. Vacuum pumps are used to apply controlled suction to the cooling process, ensuring that the plastic maintains its intended shape without distortion. This is crucial for intricate profiles or thin-walled products where maintaining dimensional accuracy is needed.

• Sizing and Calibration: Vacuum sizing tanks are used in the extrusion process to achieve precise dimensions and smooth surfaces. These tanks incorporate vacuum pumps to maintain a consistent vacuum pressure, aiding in the calibration and cooling of the extruded product. 

Vacuum pumps and technology are vital to the extrusion and ensures several benefits for plastic processing:

• No additives: Vacuum pumps help to eliminate humidity, air, solvents and other contaminants from the plastic mixture.
• Stronger products: The degassing stage improves the mechanical integrity of the product by reducing porosity.
• Uniformity and quality: Use vacuum pumps during extrusion ensures better shape uniformity, surface quality and overall appearance.
• Less waste, more efficiency: Reduces waste material increasing process efficiency, improves process throughput. 

Corrugated pipes are plastic pipes created with a series of ridges and grooves running parallel to each other on its surface. In terms of industrial use, plastic pipes like these indispensable and extrusion is the primary method of forming and producing them. Molten plastic is extruded into a moving vacuum mold and vacuum pump at 100 –200 mbara helps to form and cool plastic pipes, effectively forming and shaping it to the desired level.

Corrugated pipes are common sight in a lot of different industries right from automative, industrial and even medical technology. But the easiest place to see corrugated pipes in action is in electrical installations. They make a very dependable protective covering for electrical and telecommunications cables. Why? Because they are durable, flexible and long-lasting. Their unique design and shape make them versatile enough to be used in several ways and places.

When it comes to developing vacuum solutions for the plastic industry, we understand that high productivity and efficiency is the need of the hour. Our vacuum pumps are made to handle variable loads, reduce noise and heat emissions and make maintenance a hassle-free procedure. 

• For centralized solutions

For plastic extrusion and specifically for corrugated pipe production, where formations need to precise and processes can be demanding, we recommend our GHS VSD⁺ oil-injected screw vacuum pumps. These pumps provide offer energy-savings and intelligent monitoring through the HEX@^TM controller. Made for better performance, optimal oil separation, a smaller footprint – it is truly a machine that matches up to Industry 4.0 needs. 

• For smaller or regular installations

For smaller installations, you can also choose our DZS VSD⁺ A series dry claw pumps that offer oil-free operations, easy maintenance and lower lifecycle costs. Our DWS dry screw pump with a booster combination is also a preferred choice for some installations, depending on the process demands. We also offer intelligent liquid ring vacuum pump solutions for plastic extrusion applications.