What are the trenchless repair methods for drainage pipes?

With the rapid development of urban construction, the construction of drainage pipeline is increasing year by year, and the scale of urban underground pipe network is expanding. However, according to the investigation results of the construction and operation of drainage pipelines, some newly-built pipelines have structural and functional damage due to poor local geological conditions, except those that have been built and used for more than half a century in the early days of the People's Republic of China.

At the same time, the projects under construction sometimes affect or even damage the surrounding drainage pipelines, which seriously affects the safe operation of urban drainage. Therefore, it is necessary to master the operation status of drainage pipelines, ensure the safe operation of urban drainage, and repair defective pipelines in time.

In view of the above situation, Guangzhou Sheng Di introduced several trenchless repair methods for drainage pipelines:

1, UV curing repair technology (for overall repair)

Under the condition of not changing the position of the pipeline to be repaired, the ultraviolet curing CIPP repair technology is to make the hose saturated with resin cling to the inner wall of the pipeline to be repaired by pulling compressed air or other methods or processes, and then put the ultraviolet lamp into the inflatable hose. By using the characteristics of the resin in the ultraviolet curing hose, the ultraviolet lamp is controlled to walk at a certain speed, so that the hose is gradually cured from one end to the other end and clings to the inner wall of the pipeline to be repaired, forming a hard "pipe in pipe" structure.

2. Point repair technology (for local repair)

Repair of trenchless points of urban pipelines, also known as local resin curing method (felt-cylinder airbag local forming method), refers to a trenchless repair method in which glass fiber felt cloth coated with resin mixture is attached to the inner wall of the pipeline with airbag when the pipeline is partially cracked, leaked or damaged, and a new liner is formed in the repair point pipe by means of normal temperature, heating or ultraviolet irradiation.

Point repair technology is widely used in pipeline repair projects abroad because of its strong pertinence and fast construction speed, and it is not necessary to repair the whole section, but only to repair the damaged place. This method can greatly reduce the economic cost.

3. Folding lining repair technology (for integral repair)

Primus Line(Primus Line？ ) The system was made by Kevlar? Strengthen the liner and specially designed joints, fold the pe pipe into a U-shape, then stick the PE pipe into the main pipe with adhesive tape, and finally contact and inflate. This construction method is more suitable for pressure pipelines such as gas/oil, and the longest can reach 1km. Need to dig a working pit.

4, polymer material repair technology (for local repair)

Polymer materials repair technology adopts concrete repair materials imported from Anecon Company of the United States, mainly for pipelines over 700 mm After determining the damaged position, the construction personnel can complete the processes of quick plugging, filling, bridging and reinforcement at one time. The construction is simple, the curing time of the material is fast, the compressive strength after curing is five times of the original, the bonding strength between the material and the original pipe wall is greater than the cohesion of concrete, and the chemical corrosion resistance is good.