Sealing of lateral connections in relined sewer pipelines is necessary to prevent infiltration, exfiltration and root ingress between the liner and the lateral pipe wall.
The Interfit Tophat lateral sealing system has been used extensively in Australia and New Zealand . The final product is a strong long lasting short form liner. The proprietary Interfit silicate resin is a rapid setting material that has a relatively long pot life (20 minutes) and a short cure time (additional 30 minutes). This allows sufficient time to get the product in place and then minimises the length of time the installation apparatus is in place.
The top material is also a glass fibre composite ensuring that the lateral portion of the seal is a fully structural pipe.
The installation technique involves pushing an installation device along the pipe with a robot and then pressing the seal into place. The robot and installation device are relatively “hollow” and as such do not completely obstruct the flow.
Interflow has installed over 2,000 top hats over the last 2 years in main sizes from 375mm to 750mm. The installation process is now fully developed and a reliable final product can be routinely delivered to the client.