450mm SaniTube® Installation For Severn Trent Water

When Severn Trent Water needed to rehabilitate a heavily abrasive rising main running through an industrial estate, traditional open-cut replacement was impossible. Faced with high disruption risks and costly downtime, Sanivar, in collaboration with Colus Ltd and CPC, delivered a groundbreaking solution – the world’s first 450mm pull-through SaniTube® installation.

By combining SaniTube®’s superior abrasion resistance with the structural strength of a CIPP liner, we extended the pipe’s integrity by 80 years, ensuring long-term resilience. And all within just 60 hours.

Client               Severn Trent Water

Contractor       Colus Ltd and CPC

Project             Gosport

Completion      November 2022

OVERVIEW

Sanivar, working with Colus Specialist Projects and CPC have recently completed the first ever 450mm pull SaniTube® installation, a world first of this diameter, on an abrasive main in Cheslyn Hay, Cannock. The pipe could not be replaced using open cut, as its course ran through an industrial estate and under above ground infrastructure, including aquatic tanks and commercial greenhouses.

CHALLENGES
The project posed several challenges:

• The potential for high customer disruption amongst business and residential stakeholders.
• The pipe could not be replaced using open cut, as its course ran through an industrial estate and under above ground infrastructure, including aquatic tanks and commercial greenhouses.
• High cost associations with having the main offline for a considerable amount of time.

OUTCOME

Sanivar proposed the use of 450mm pull through SaniTube® liner, to assist in the refurbishment of a 180m section of 500mm rising main. SaniTube® offered the required level of abrasion resistance but is not in itself a full structural liner despite withstanding pressures of up to 16 bar. The newly launched 450mm diameter liner would inflate to 490mm under 5 bar pressure, sufficient to meet flow requirements. It was then decided to combine the abrasion resistant properties of SaniTube® with the structural strength of a CIPP liner. 

To restore structural integrity to the main an 8mm Berolina HF liner was used, a conventional CIPP system that adheres to the existing asset but has limited resistance to abrasive or corrosive forces. 

After analysing the potential of transferring negative pressure from one liner to the other it was decided that SaniTube® offered the optimum protection against both abrasion and negative pressure, as it does not adhere to the relined pipe but sits inflated within the pipe.

The works were started and completed in less than 60 hours. During this time, the team managed to rehabilitate the host pipe and extend its structural integrity by 80 years, as wellas installing a unique SaniTube® product with a minimum life span of 25 years against the abrasion, which was considerably longer than any other product, and offered the opportunityto remove and reline in the future as needed. This demonstrates the versatility of SaniTube® both as a robust stand-alone lining system and as a complimentary system offering the highest abrasion resistance when used in conjunction with other CIPP lining technologies.

Need an innovative, high-performance pipe rehabilitation solution? Learn more about SaniTube® here, or contact us today to see how Sanivar can support your next project.