Hunter Water Corporation - which is after Sydney Water Corporation the second largest utility in the Australian state New South Wales - had a break on a DN 500 Ductile Iron Cement Lined (DICL) sewer rising main in a hard to reach area under a creek. This asset is important to Hunter Water and downtimes have to be kept at a minimum. Sydney Water had Primus Liner DN 500 and corresponding Primus Line® connectors on stock and supplied the material to Hunter Water.

Hunter Water assigned the installation of the project to Interflow, which is the most experienced Primus Line installer in Australia to date.

After draining and cleaning the main using water jetting and rubber discs, the existing pipeline was inspected by CCTV. A significant hole was found in the pipe wall and a CIPP patch liner was installed to prevent stones and sand from falling into the main: The patch can withstand the soil loads, but is not able to stand the operating pressures of the sewer rising main. In addition, pressure relief valves were attached to the existing pipeline. In case ground water would infiltrate into the annulus, it could be released through the monitoring valves. Subsequently, the Primus Line® system could be installed over the length of 80 metres and through a 30 degree bend.

A pressure test with 8 bar was performed before the sewer rising main went back live.

• Technical Details • Transported Fluid: Residential wastewater
• Diameter of Host Pipe: DN 500 • Material of Host Pipe: Ductile Iron Cement Lined
• Operating Pressure: 5 bar • Primus Line® System: DN 500 PN 16 • Total Length: 80 metres • Bends: 1 x 30 degree horizontal bend

About Primus Line® [separate box, optional]

The Primus Line® system is referenced in EN ISO 11295:2017 – classification and information on design and applications of plastics piping systems used for renovation and replacement. The Primus Line® system also complies with the technical standard DVGW VP 643 – flexible textile-reinforced plastic inliner for pipe-relining of gas high pressure pipes. The system consists of a Kevlar®-reinforced liner and specifically developed end fittings. The liner accommodates the operating pressure of the pipe, due to the reinforcement layer and does not bond to the host pipe. An annulus space remains. The liner is seamlessly manufactured at an ISO 9001 certified production plant in Germany and transported to the site on reels. Due to the flexibility of the material, the liner can traverse angles of up to 45 degrees, can be installed in lengths of more than 1,000 m in one pull, and has an installation speed of up to 600 m per hour.