Manufactured in accordance with DIN 16962 from Polypropylene Random (Type 3) and available in cross-sections from 20mm to 315 mm. For the manufacture of the fittings the company uses raw material with a low melt flow index, identical to that of its pipes so that the mechanical strength of the pipe does not differ from that of the fittings. The fittings are certified by SKZ.

Produced with a wall thickness equivalent to 25 bar since the resistances created in the fittings are much greater in relation to those of the pipes.

The considerable thickness of the walls of the PN 25 fittings allows us to improve the design of the internal geometry of the fittings, thus considerably reducing the value of hydraulic losses and improving flow through the system. For example, the local resistance coefficient (æ) of the 90° elbow for the usual PN 20 fittings is 1.2 whereas for the PN 25 fittings it is 0.9, i.e. 25% less.

The brass parts are reinforced, heavy-duty and of low hardness (105 Brinell) thus the possibility of cracking, particularly common in fittings with female threading, is eliminated. They have cross-shaped grooves at the base of the brass insert so as to prevent torsion and consequent detachment of the metal from the plastic part.

Parametric fitting retaining grooves, in which one side of the groove has negative declination, from the outside in, so as to retain the PP-R material and prevent detachment of the metal part from the plastic part in the presence of tensile forces.

The PP-R overlaps the male brass inserts on the inside. In this way the metal parts are isolated from the installation, and solid deposits and consequently reduced flow are prevented. Moreover, the system is protected against electrochemical corrosion.

For the heating-plumbing technician’s convenience Interplast produces an intake with predefined connection distances for the bath battery allowing connection of the hot or cold water lines either from the floor or from the wall.