In the past, we used the traditional excavation rehabilitation technology for pipeline rehabilitation, which is a construction method that needs to excavate the road surface. Then trenchless pipeline rehabilitation technology rose in developed countries in the 1970s, and then gradually formed an industry. Compared with the traditional pipeline rehabilitation technology, this technology has obvious advantages in ensuring the safety of pipelines, structures (buildings) around the project, and ensuring smooth traffic, which is attracting more and more attention from all countries.
1. Small environmental impact and floor area; short construction period; little impact on traffic; less earthwork, dust, noise, and impact on the surrounding environment.
2. The comprehensive cost is low, the demolition is few (none); the road excavation is avoided (less); especially crossing rivers; important traffic lines and buildings; protection and monitoring needed is less.
3. The construction period is short, the approval is less, the coordination is less; the construction assistance is less, and the construction preparation time is short.
Pipeline rehabilitation technology can be divided into four types: CIPP (cured in place pipe), spile rehabilitation method, in-situ pipe preparation method and coating rehabilitation method.
Rehabilitation Principle: the resin heating or light curing principle is generally adopted, which will not form resin. Heat the pipeline with water pressure or air pressure, and then heat the hot water in the pipeline to solidify the resin in the pipeline and form a new pipe. It can rehabilitate the whole pipeline at the same time, and also need to repair the leakage of local interface.
For some prosperous urban areas, environmental protection areas or buried pipeline areas, large-scale excavation is not suitable, but trenchless pipeline rehabilitation method can be used to repair or replace some old pipelines, so as to improve the performance.