BURSTLINING

Trenchless replacement of sewage pipelines using the Burstlining KMR method (also known as pipe cracking or pipe bursting) consists in crushing the pipeline and pushing its fragments together with the surrounding soil to the sides with a special head pulled through the old pipeline with a winch. At the same time, a new pipeline is pulled behind the head and successively assembled from short pipe modules. The modules may have the same nominal diameter as the old pipeline (in this case we speak of size-for-size burstlining; rope winches are used in this case) or may be one or two dimentions larger (in this case rod winches are used; work involving these must be carried out by experienced contractors). Due to the length of the pipe modules, they are joined together inside the manhole. The winches are also compact and fit inside typical manholes. This allows work to be carried out without the need for excavations. Experience has shown that up to 50 metres of sewer per day can be replaced using this method. Once the work is complete, the new pipeline made up of short pipe modules fully assumes all the functions of the old sewer – it is self-supporting and ensures the required hydraulic capacity and complete tightness.

The KMR burstlining method can be used to replace pipelines with large misalignments, cracks and deformations. However, the sewer must be unobstructed in order to allow the winch cable to be pulled through or the rod to be pushed through.

As a result of the application of size-for-size burstlining we obtain a hydraulic effect similar to the results of CIPP renovation. However, when using the burstlining method, the bursting head destroys all imperfections of the old pipeline (e.g. deformation of cracked pipes, misalignments, etc.) and thus the new pipeline is characterised by a constant cross-section and even bottom along its entire length. In addition, the low fixed costs of this technology make size-for-size burstlining worth considering as an alternative method to sewer renovation by CIPP.