HDPE Pipe Shredding for Sustainable Plastic Pipe Recycling

Machines in the WLK series are ideally equipped for a wide range of plastics tasks. The machine design is characterized in particular by its durability and robustness. Thanks to the conveyor belt cut-out, all machines can be seamlessly integrated into any production line. They also offer a wide range of options in terms of drive and cutting geometry.

With rotor lengths of 1,400 to 2,200 mm, the shredders in the W5 series shred large-volume plastic tanks and plastic garbage cans with ease. The hydraulically upward pivoting screen basket and the inspection flap allow foreign objects to be removed quickly and facilitate maintenance. Large quantities of plastic flakes can be removed via the wide conveyor belt cut-out.

With their extremely sturdy design and large rotor diameters of up to 700 mm, shredders from the S7 series offer almost unlimited application possibilities for shredding plastic waste. They are up to any challenge and can be equipped with a high-torque hydraulic drive.

The machines in the PowerLine series can be used universally. Variable equipment and sizes enable precise adaptation to your specific requirements. The counter knives are user-friendly adjustable from the outside and protected by an additional cover plate.

The plastic polyethylene (PE) is processed in various degrees of density - from PE-LD (low density) to PE-MD (medium density) to particularly robust PE-HD (HDPE). In addition to polyethylene, WEIMA also shreds other thermoplastics such as polypropylene (PP) and polyvinyl chloride (PVC). Thermoplastics are characterized by their malleability when heat is applied and can therefore be welded without any problems. Thermoplastic waste and production scrap can also be processed into high-quality recycled granulate in an energy-saving way. This significantly reduces the use of fossil raw materials for the production of new plastics.

HDPE plastic pipes are lightweight, stable, flexible and extremely resistant to chemical corrosion. They can withstand high pressures and are ideal for water pipes, gas transportation and cable protection. Compared to metal pipes, however, they have a lower temperature resistance. For HDPE pipe production, the granulate obtained by plastic pipe shredding is used. This is melted in a single or twin-screw extruder and formed into an endless pipe under constant pressure. After cooling, the pipe can be flexibly cut to the desired length. Thanks to their durable thermoplastic properties, HDPE pipes can be used for decades and can be efficiently recycled at the end of their life cycle.

Source: Kunststoffrohrverband e.V.

Plastic pipes are central components of modern infrastructure. Whether energy supply, logistics or telecommunications - little works without HDPE pipes. The demand for new installation and replacement is high. Companies such as PIPELIFE, UPONOR and NEPROPLAST are among the world's leading producers.
However, as production increases, so does the proportion of rejects and old pipes. Both material streams are valuable resources that can be reused through HDPE recycling. This keeps the plastic in the resource cycle in the long term. The extrusion process in particular regularly produces HDPE pipe waste - for example, when the system is started up in the form of large start-up lumps, also known as start-up cakes or start-up lumps. It also happens that pipe segments or pipe spools do not meet the quality specifications and are therefore recycled directly in the plant by plastic pipe shredding.

Material recycling
After used plastic pipes have been collected, sorted and cleaned, high-performance shredders grind the material into homogeneous regrind. This can be processed into high-quality regranulate in extrusion plants - the basis for the production of new pipes from recycled plastic within the in-house recycling process.

Raw material processing
In contrast to material recycling, the aim of raw material processing is to break down plastics back into their chemical starting materials. These raw materials are then used to produce new polymers. However, as the fractions are usually not completely homogeneous, this can lead to a loss of quality in the production of exact formulations.