1. The inverting liner (CIPP) repair process (also known as in-situ curing method) was invented by the British in 1971 and is the most widely used trenchless repair process in various countries in the world. Its applicable range is 150 mm to 2700 mm. Based on the ASTM F1216 standard, the liner was designed as a structural liner. Entering the pipeline from the inspection well, without digging the ground, the pressure of the water body is turned over and closely attached to the original mother pipe. After heating and curing, the pipeline can completely rely on the original pipeline and can independently bear the internal and external pressure, the new pipe after repair will basically not affect the cross section of the water, and the normal service life is more than 50 years, which is a very popular repair method in the world.

2. Ultraviolet curing CIPP repair technology refers to the method or process of pulling the resin-impregnated hose first by pulling compressed air without changing the position of the pipeline to be repaired, so that the hose is tightly connected to the inner wall of the pipeline, and then use the characteristics of the resin in the hose to cure with ultraviolet rays, put the ultraviolet lamp into the inflatable hose and control the ultraviolet lamp to walk at a certain speed in the hose, so that the hose gradually solidifies from one end to the other. Attached to the inner wall of the pipeline to be repaired, a layer of hard "pipe-in-pipe" structure is formed, so that the underground pipeline that has been damaged or lost its transportation function is repaired in situ.

3. Non-excavation point repair of urban pipelines, also known as local resin curing method, refers to the case where the pipeline is partially cracked, leaked, or damaged, and it is necessary to urgently repair the pipeline due to local damage to the pipeline. Pressing the glass fiber felt cloth coated with the resin mixture against the inner wall of the pipeline with an air bag, curing it by means of normal temperature, heating or ultraviolet irradiation, etc., and forming a new inner liner in the repair point tube.