How Does A Plastic Extrusion Machine Work?
As a manufacturer of PVC/PP/PE and other composite pipes, it is likely that you have already learned about extruders and operated one.
Whether you already have a machine or are considering purchasing one, understanding the principles of plastic extruders is invaluable for both purchase and routine maintenance.
Especially when buying a new machine, understanding the principles will help you to determine if this plastic extruder is the right machine for your current high volume production. Make the most informed choice.
What is a plastic extruder?
A plastic extruder is a high-volume manufacturing process for pipes.
In simple terms, a plastic machine is a processing machine that melts plastic and continuously passes the liquid plastic through the mouth die by internal pressure to form the desired pipe shape. It is characterised by a high degree of consistency and uniform thickness of the tube body.
We have also added a PLC controlled shear to cut the formed pipe into fixed lengths of plastic pipe.
The standard of pipe produced is designed to customer requirements, ensuring full compliance every time the product is formed.
How plastic extruders work
Extruders are relatively simple in structure, the material is melted and then fed into a fixed die, which is temperature controlled to achieve the desired shape of the pipe. This is then cut to form the final product.
1. Screw system
As the material is fed into the extruder, the temperature generated by the rotation of the screw causes the plastic pellets to melt. Generally this part is located on the extruder head. It can also be subdivided into three specific sections.
1. Feed zone: This is the part where the plastic pellets are fed.
2. Melting zone: melting of the plastic pellets.
3. Mixing zone: The molten plastic is measured and mixed to produce a uniform temperature.
2. Temperature control system
To ensure a consistent pipe shape, it is necessary to maintain a consistent temperature in the barrel of the extruder. This prevents the production of sub-standard products due to inconsistent temperatures. We have therefore designed the temperature to decrease gradually from front to back, using air cooling as well as water cooling before reaching the mould. The moulding rate is ensured.
The die is the core component of the extruder, allowing the plastic product to be extruded continuously to produce a regular shape and uniform length. Moulds need to be individually tailored to suit different applications in different industries. Our engineers produce the corresponding type of die for the specific application at the beginning of the design process.
4. Cutting systems
For this purpose, PLASTIC EXTRUSION MACHINES offers a professional PLC integrated cutting system. Precise cutting with virtually zero rejects. Depending on the requirements, only the required length needs to be entered into the control system.
Starting a customised plastic extruder
Having served a number of customers worldwide over the years, we have a strong technical team that is able to do careful research in response to customer problems. Matching plastic extruders that exactly meet the needs of our customers. We have been recognised by many customers. Trust us to provide you with expert advice on plastic extruders and their purchase.