Why Replace Existing Pipelines When They Can Be Rehabilitated Using Polyethylene Pipes and Fittings

During the lifetime of a pipeline the point is reached where the cost of water loss, leakage management, maintenance and repair works, together with the poor service to the customer justifies its replacement or rehabilitation. Trenchless rehabilitation techniques can have a lower cost and cause substantially less disruption to existing assets and the general population than conventional ‘open cut’ techniques. 

As trenchless technology has developed and increased in use, so has the use of polyethylene pipes in applications such as slip lining, close fit lining and pipe bursting. The majority of pipeline renovation and replacement techniques now use polyethylene as their principal pipe material and the techniques have been developed to the point where they have been used to rehabilitate pipelines of up to 1,400mm internal diameter. 

This presentation will give an introduction to the different methods by which water pipelines can be rehabilitated using polyethylene pipes and liners through the use of a variety of trenchless technology techniques. It shall also explain how Engineers and other technical staff working for water utilities can use the standard ISO 11295 to help identify and specify the most appropriate technique for their particular situation. 

The original polyethylene pipe materials were not intended for such applications and so the greater use of polyethylene in trenchless technology has been a key driver in the development of tougher materials. One development has been PE100 materials that have a high resistance to slow crack growth through the wall of the pipes. Such materials are referred to as HSCR PE100 and PE100-RC. The presentation will explain how slow crack growth can be initiated by the use of trenchless technology applications and how the new generation of PE100 materials resist the growth of cracks through the pipe wall.