Plastics and composites for HDPE Pipes

In the field of installation systems, the plastic and multi-layer composite pipes are becoming increasingly important due to rising raw material prices for metals such as copper and stainless steel. However, not every plastic pipe can be used for all applications. When selecting the material, it is therefore important to take into account certain restrictions, which are explained in more detail in the following text.

HDPE Pipe

In the field of installation technology, plastics are predominantly thermoplastics used. They are solid at normal temperature but elastic. When heated, the solid state changes to a soft, malleable state. Tubes can be bent or widened. After rapid cooling (eg with cold water), the new shape is retained. When a thermoplastic is reheated, the material returns to its original shape (memory effect - the material "remembers").

Thermoplastics are z. As polyethylene (PE), polypropylene (PP), poly-butane (PB) and also polyvinyl chloride (PVC).

Thermosets, on the other hand, retain their shape even when heated, so they are not subsequently malleable. In the installation compartment, they are used for toilet seats, bath supports or mounting foam, just to name a few examples. polyethylene

In the case of polyethylene, a distinction is made between high density (PE-HD, for high-density) or low-density (PE-LD, for low-density). PE-HD has a denser structure than PE-LD. As a result, tubes made of this material are more rigid (and somewhat unruly when processing the role), but it suffice less wall thicknesses. This makes PE-HD pipes lighter than PE-LD pipes. Polyethylene can be additionally crosslinked, which further improves the material properties (temperature resistance).

There are 3 different methods available:

1. PE-Xa: Engel procedure. Chemical process with the addition of peroxide

2. PE-Xb: Chemical process with the addition of silane

3. PE-Xc: Physical procedure

The PE-Xc is bombarded with accelerated electrons, which makes the molecules more cross-linked . This process is applied to the Henco multi-layer composite pipe and ensures the highest quality.