The City of Winnipeg was confronted with such a situation: A DN 250 pipe with a length of 175 meters and three 45-degree, one 22.5-degree and one 11.5-degree bends needed to be rehabilitated. The line with a normal operating pressure of 150 psi had an active leak and was originally considered for CIPP. However, using this technology under the river and with all the bends was not feasible. Therefore, the Primus Line® FFRP was presented to the engineering consultant and the city as the best option for rehabilitation and was subsequently used.
A CCTV inspection prior to installation revealed an extra 45-degree bend less than 20 feet from the end of the pipe. Under these new circumstances, the originally intended low pressure connector could not be assembled and had to be replaced by a medium pressure connector. Moreover, a sharp protrusion was detected and had to be removed before liner installation. The general contractor located a milling robot capable of navigating the pipe and successfully removed the obstacle.
Afterwards, cleaning could be conducted to create a free inner diameter of the respective pipe which is a prerequisite for the installation of the FFRP: The free diameter ensures that no damages occur during the pull-in process.
With all preparations in place, lining the pipe with Primus Line® FFRP only took 30 minutes to pull the length of the pipe. The liner was inflated with air and rounded back to its original state. The connectors were installed on both sides, completing the lining in one day. After a successful pressure test and disinfection, the rehabilitated water main could be handed back to the City of Winnipeg with a minimum extension of useful life by 50 years.
