The extent of the world’s dependence on plastic is no secret, but people probably do not think about how this plastic is manufactured, processed, and turned into daily-use objects. This task is largely handled by PVC (polyvinyl chloride) extruders, which are machines that melt and transform plastic into desired shapes, like pipes, sheets, and films. This continuous process is standard in many industries, as it can help produce a large number of plastic products.
PVC extrusion – Process overview
In the plastic or PVC extrusion, molten plastic is given a consistent and continuous profile by pushing or pulling it through a shaped die (mold). This material moves through three zones in the machine.
- The feed zone, where raw material or plastic is put into the machine
- The melting zone, where the plastic is melted to reach the desired temperature
- The metering zone, where the last bits of molten plastic are turned into a homogenous mix before it goes off to cool
Features of PVC extrusion machines
1. Specialization
Plastic extrusion machines can quickly and easily be adapted to meet the needs of different businesses. This specialized production offers businesses a unique advantage over their competitors and helps ensure quality and capital turnover.
2. Efficiency and versatility
Extruder machines can be quite efficient, providing a high output with low energy consumption and manufacturing costs. They can also be used across industries to create various types of plastic products, making PVC extrusion machines multi-functional.
3. Scale
Extruder machines can be a great solution for industries looking for quick yet large-scale production. These machines are also easy to use.
4. Advanced technology
Finally, a key feature in most extruder machines today is integration with high-grade tech to ensure uniformity during production. This makes the machines capable of detecting the ratio of the raw materials and current and voltage levels online and adjusting systems to ensure consistent results.
Types of PVC extrusion machines
Most extruders are made up of seven key components—feed assembly, extruder barrel, extruder screw, extruder drive, extruder discharge or die system, heating/cooling system, and safety and control features. Even with these components standard in most variants, extruder machines can be classified based on the type of material extruded and the final shape of the product. Some of these types include:
- HDPE (high-density polyethylene) pipe extrusion line transforms HDPE resin into pipes.
- A plastic sheet extrusion machine feeds plastic through a flat-sheet mold to make sheets.
- The blown film, cast film line, multi-layer blown film, and PP TQ film plants produce packaging films.
- Raffia tape stretching line produces synthetic stretched tapes for making bags, artificial grass, etc.
- PP/HDPE and PET box strapping plants produce straps used in packaging and bundling.
- An extrusion coating lamination plant produces a protective plastic layer that coats materials.
- A PET recycling plant uses extrusion to process used plastic.
Applications
Extruder machines are widely used across industries to quickly produce nylon, polyethylene, acrylic, polypropylene, polycarbonate, ABS, PVC, TPR, and more. That said, these machines are commonly associated with major industries like construction, automotive, and healthcare.
Construction projects: Here, PVC extrusion is required for plumbing, drainage, and electrical conduit systems.
Automotives: Extrusion helps produce car frames, doors, and window frames. Plastic is also used as insulation for electrical wiring, underbody coating, and interior trims.
Healthcare sector: Extruded plastic is used to make IV tubes, blood bags, dialysis kits, etc.
