SGS is a large diameter composite PE + steel pipe used for non-pressure underground drainage systems and embankment crossings. It is manufactured using proprietary technology without the use of adhesives or other polluting substances normally found in the manufacture of similar products. SGS consists of a smooth internal polyethylene surface (A) surrounded by a stiffening spiral-wound steel profile (B), and covered with an outer layer of PE (C). This external layer can be rectilinear (externally smooth) or can follow the form of the metal stiffening (corrugated external surface).
Supply and lay composite pipes with structured wall profile complying with UNI 11434, formed by a smooth internal layer in polyethylene (PE) for fluid flow, a spiral wound steel structure providing ring stiffness and a covering external protective layer in polyethylene (PE). Nominal internal diameter (DN/ID) ___ mm, class __ ring stiffness (PS ___ kPa with 3% deflection).
Connections between pipe lengths by means of spigot and socket joints either with gasket or electrofusion.
The official standard reference for the manufacture and testing of composite PE-steel pipes is UNI 11434:2012. This standard has been introduced in order to certify these types of pipes, as their behaviour, characteristics and composition differ from those manufactured using only plastic materials. The steel used to form the support profile of SGS pipes complies with standard UNI EN 10346, with a tensile strength of 270 MPa and elongation > 20% as provided for by standard UNI 11434.