Double Pipe Sewer System for the Marche Region in Italy

In order to protect the environment from being contaminated in cases of pipeline failure, environmental specifications require double security measures. The design engineers therefore opted for coaxial pipes: any leakage eventually coming out of the inner pipeline, would be retained by the outer pipe. After a thorough comparison of today’s large variety of available pipe material, Marche Multiservizi decided to utilize HOBAS® Products. The HOBAS Double Pipe, or as the Italians would say “Doppiotubo”, is a pipe in pipe system made of CC-GRP Pipes. A wide range of HOBAS Accessories and Special Fittings complete the double safety system. 1.4 km of double pipe have been utilized for the Torraccia project, with inner and outer pipe diameters DN 400 and DN 500 respectively and a pipe stiffness of SN 10000. The inner pipes are kept in place with spacer rings. Special HOBAS Couplings with 4-lip rubber gaskets ensure complete leak tightness in both ways, namely from in- and outside the pipeline. The installation proceeded extremely fast and with ease thanks to the preassembled double pipes, and the relatively light weight of the pipe material.