The task

By utilising the KrasoSluice inversion drum, DrainsAid were able to undertake the preventative rehabilitation of a 54m x 150mm sewer network. We opted to use the Hot CIPP lining method in conjunction with a Type II structural lining supplied by RSM, to complete the manhole to manhole repair. Using the Hot cure method allowed us to speed up the curation process, meaning disruption was kept to a minimum for the area’s residents.

As the sewer line was located at the small residential Church Lane, a road closure was required to undertake the works safely and efficiently. As usual, all traffic and pedestrian management was set out by NRASWA trained operatives in accordance with the approved code of practice.

Hot CIPP process

Once the site was established, the 150mm diameter line was surveyed using our CCTV investigative equipment to establish the current flow conditions. The line was then cleaned by high-pressure water jetting, before a second CCTV investigation was completed.

The team ensured the liner was prepared for inversion by securing the tail end with band straps , rope and burp tube. The correct size nozzle was then fitted to the sluice and secured with the clamp, before the thermo wires were correctly placed at the upstream and downstream manholes.

In a flat condition, the liner was guided through the sluice while compressed air was applied to the sluice chamber. As the liner was pushed into the chamber, water was added to help continuously invert the liner. When the liner was in position, the water was heated to accelerate the curation process, which took a number of hours.

The works were completed within one day while the majority of residents were at work, ensuring only minimal disruption for the local public. Utilising CIPP trenchless technology allowed us to complete works quickly, without the need for excavation, which would have caused major disruption for the street’s residents.