Wall thickness：14mm

Length：260m

Application：Sewage pipe

Project Introduction：The sewage pipe to be repaired was located under the viaduct, with a diameter of DN1200mm, a single section length of 260 meters, and a burial depth of 6-8 meters. During inspection found that there were local cracks and leaks in the pipe. If not handled in time, it may affect the viaduct and surrounding communities.

Construction Challenge：

1. Difficulty in manual laying:

UV-CIPP liners for large-diameter pipes usually have the characteristics of high strength and high toughness. Although this ensures that the repaired pipes can withstand huge pressure, it also adds many obstacles to laying. Meanwhile, to meet the needs of large-diameter rehabilitation, the wall thickness increased, and the weight rose accordingly. Large cranes and other lifting equipment were difficult to operate in limited construction sites, and manual stacking and laying were even more difficult, a little carelessness may cause liners damage and affect the rehabilitation quality.

2. One-time curing over ultra-long distances:

Single-section long-distance curing put extremely high requirements on the performance of our UV Curing system. Our UV Curing system was equipped with imported high-pressure ultraviolet lamps and power systems to ensure fast curing speed and good results. However, in actual operation, the curing distance of up to 260 meters posed a severe test to the continuous and stable operation of our UV Curing system. During the curing process,our UV Curing system must maintain stable performance to ensure that ultraviolet light can evenly cover the area to be repaired, which undoubtedly increased the complexity and risk of operation.

3. Special process treatment for single-section long-distance curing:

Due to the single-section long-distance curing of 260 meters, the UV CIPP system cannot complete the curing at one time. Based on the actual situation and consultations with multiple units, a plan of one-time laying and curing at both ends was finally formed, and eventually,this project had been successfully completed.