Trenchless pipe rehabilitation technology first emerged in the oil and gas industry, mainly used for the renewal and repair of oil and gas pipelines. After that, trenchless drain pipe repair technology gradually developed, and with the application of new pipes such as HDPE pipe, it was rapidly promoted. With the advancement of science and technology, foreign trenchless pipe rehabilitation technology has maintained a rapid development momentum, but domestic trenchless pipe rehabilitation technology is still in its infancy, and there is still a big gap compared with foreign professional technology. However, the market prospects for this technology are very broad.
(1) Aiming at the transformation of old pipeline facilities, it can meet the needs of structural renewal and capacity expansion at the same time.
(2) To minimize the trouble of demolition and relocation and damage to the environment, and reduce the additional investment of the project.
(3) Partial excavation of work pits reduces the amount of road excavation and the impact on the public transportation environment.
(4) The use of hydraulic equipment, which have the feature of low noise, and meet environmental protection requirements, reduces the factors that disturb the residents, and significantly improves social benefits.
(5) The construction speed is fast and the construction period is short, which effectively reduces the project cost.
(6) The project is safe and reliable, and the service performance is improved, which is beneficial to the later maintenance of the facility.
At present, the world's relatively advanced trenchless rehabilitation technology has three categories (including more than 10 process technologies). One is to use resin curing methods to form new drainage pipes inside the pipes, such as CIPP, on-site curing, and other processes. The second is to use the small pipe to pass through the big pipe, which is inserting a small drainage pipe inside the original pipe to solve the urgent need, such as short pipelining, U-shaped pipe dragging, and other processes. The third is to use the spiral pipe method to form a new pipe inside the original pipe by winding method, such as spiral winding method.
The overall advantage of the trenchless pipe rehabilitation method is smaller rehabilitation negative impact, less space occupied, and weaker impact on the ground, traffic, environment, and surrounding underground pipelines. Therefore, the use of trenchless drain pipe repair is imperative.