Carrogate pipe is the most widely used pipe used in the transportation of urban waste water; It is a double-walled polyethylene tube that has a grooved appearance and a smooth inner surface. Their branches are produced in lengths of 6 and 12 meters along with connectors called couplers and washers with a resistance of 16 to 128 kilonewtons per square meter. Except for the models reinforced with metal, these pipes have a 50-year erosion warranty.