Pexal is a multilayer pipe, consisting of two separate materials: a metal and a plastic part. The inner layer is made of type B cross-linked polyethylene, bonded through an adhesive film to an intermediate aluminium layer. One more thin layer of adhesive is applied, followed by the outermost layer of the pipe, which is composed of type B cross-linked polyethylene (precisely like the inner layer).

The key elements to ensure the quality and reliability of the pipe throughout its life cycle are raw materials (which must be selected according to appropriate criteria) and assembly, which must be performed in a skilful manner.

No detail is overlooked!

In the Pexal range, the inner and outer layers are made of PE-Xb: there are different types of cross-linking on the market. Furthermore, there is also a standard that imposes a "minimum cross-linking" that varies according to the process used.

Our choice fell on type B, the one obtained through silanes. It can be made directly at the company's factories, so there is total control over the processing, and the guarantee that the entire process is carried out in accordance with all standards. At the end of pipe assembly, processing takes place in special steam tanks that are exclusively used for this purpose.

Multilayer piping is unique in that it incorporates (in a single pipe) the advantages of both metal and plastic solutions: for example, the corrosion resistance of plastic and the high pressure as well as temperature resistances typical of aluminium.

However, this is true only if the pipe is assembled with an adhesive that perfectly bonds the two layers. The adhesive compound used in our multilayer has undergone years of research and improvement, enabling it to maintain a constant seal for many years.

The core of the pipe consists of a virgin aluminium intermediate layer designed for maximum physical and mechanical performance without compromising flexibility. It is butt welded with TIG technology to ensure perfect uniformity and an even distribution of forces. Moreover, in this way, flexibility and thickness are identical at any point on the pipe.

The system characteristics

Pexal range is available in diameters ranging from 14 to 110 mm. It is an ideal application used in multiple areas, such as hot and cold water plumbing systems, but also high and low temperature heating as well as cooling equipment. Compressed air systems are another possible application, given the high resistance of plastic to chemicals and its extremely smooth interior surface .

It can be supplied in bars or rolls of various cuts up to 500 meters, or coated with 6 to 13 mm heat-insulating sheath, as well as with single or double corrugated sheathing (so with double piping included).

Moreover, its extremely smooth inner surface reduces pressure drops as well as fouling and algae formation (the aluminium intermediate layer acts as a total barrier to light and oxygen). Clearly these pipes are usually installed concealed, so it is essential that they are of a durable construction (Pexal ensures a life of at least 50 years).