Pipelines which are in otherwise in acceptable service condition can have defective sections, for example a pipeline that has suffered isolated damage due to nearby excavation, a pipeline with a crack and heavy root infestation, or a pipeline which has an isolated leaking joint.
Interpatch is a short section of glass reinforced plastic (GRP) that can be used to repair localised sections of damaged or defective pipelines with diameters from 100mm to 750mm. Examples would be a pipeline that has suffered isolated damage due to nearby excavation, a pipeline with a crack or root infiltration point, or a pipeline which has an isolated leaking joint.
Interpatch has been designed as a structural fitting as well as a seal. Interpatch is recommended if renewing (lining) the entire pipe is not economical or when traditional disruptive dig and replace techniques are too costly or not practical.
Interpatch is constructed of a fibre-glass matting which is saturated with high performance, fast curing silicate resin. Interpatch is offered in a standard thickness according to pipe diameter, however the thickness of an Interpatch can be customised by overlaying additional layers of fibreglass matting to provide a stronger fitting if required. A standard repair length is 1.2m however longer sections can be repaired by overlaying successive Interpatches.
The glass fibres give Interpatch superior strength and stiffness such that it can be designed as a stand-alone fitting to AS2566. The resin selection is optimised according to pipe size. In reticulation pipe sizes (diameters to 300mm), Interpatch uses an Interflow proprietary resin specifically formulated for faster cure in ambient conditions. Cure is achieved in less than1 hour making installation fast, safer, and less disruptive. In larger pipe sizes, where installation is usually more difficult, the resin is selected to provide an optimum balance between fast cure and long pot-life to ensure a low-risk successful installation.
Installation is fast and no digging is required. Installation is achieved by using an inflatable packer to move the patch to the repair location from the nearest manhole. The packers are available in a range of sizes and are fitted with hollow voids to enable installation during live flow without the need for bypassing.
Interpatch can be installed in pipes constructed of brick, concrete, pvc, vitrified clay, asbestos cement, cast iron. It is not suitable for polyethylene or polypropylene pipes.