In the older parts of a city, the main sewer lines are usually in bad repair and require relining. The existing main sewer line may be relined with a plastic pipe liner which is inserted within the existing sewer line. In order to permit insertion of the plastic pipe liner the outside diameter of the liner is less than the inside diameter of the main sewer so that a space is formed between the plastic pipe liner and the main sewer line. In connecting a lateral sewer line to a plastic pipe liner, it is necessary to fill this space at least around the lateral sewer line where it meets the main sewer line with a grout material. Methods which contemplate the connection of a lateral sewer line to a plastic pipe liner usually entail prolonged periods of service shutdown and therefore an inconvenience to the home owner. Such methods are usually very costly and become prohibitive when several laterals are encountered in relining a main sewer line.
USPTO Backgrounds
USPTO Backgrounds