Thoroughly refined protection: A solution for pipeline repair systems derived from extensive practical experienceFacing a damaged sewage pipe that was buried 15 meters deep, had a diameter of 1 meter, and was 209 meters long in a single section, the traditional "open and cut" repair method was no longer feasible. However, an experienced team completed the pipe repair in just a few hours through "minimally invasive surgery". Pipes are like the veins of a city, quietly extending underground and carrying the lifeblood of modern society. When these "urban veins" become aged or damaged, the repair work becomes a highly demanding systematic project that requires extensive experience, technical expertise, and sound judgment. Rich experience in pipeline repair not only indicates handling a large number of cases, but also represents the ability to quickly formulate a complete solution of "inspection - diagnosis - repair - verification" when dealing with complex pipeline diseases. This experience accumulation is the key to seamlessly connecting technical theories with complex realities. 01 Experience Accumulation: The Conceptual Transformation from "Open Surgery" to "Minimally Invasive Surgery in Cities" The urban development in our country has shifted from large-scale expansion to a new stage of improving the quality and efficiency of existing infrastructure. This transformation has brought to the fore the problems of outdated underground pipelines. According to statistics, the water loss due to leakage in the water supply pipelines in our country is enormous each year, even exceeding the expected water delivery volume of the South-to-North Water Diversion Project. In the past, pipeline repair was almost equivalent to a "major excavation" approach involving extensive digging. This method not only severely disrupted urban traffic and residents' lives, but also had a long construction period and extremely high costs. Especially in densely populated urban areas or in complex sections such as crossing rivers or railways, it was almost impossible to implement. Non-invasive repair technology emerged and quickly became the mainstream in the industry. This technology, known as the "minimally invasive surgery for cities", has its core advantage in being able to restore pipeline functions efficiently and precisely with minimal surface disturbance. This shift in concept is a concentrated manifestation of the accumulation of industry experience: from passively responding to pipeline failures to actively conducting full life cycle management and preventive repairs. Experience tells us that no single repair technique is universal. True professional competence lies in the ability to precisely select and combine the most cost-effective and long-lasting solution from a wide range of methods based on dozens of parameters such as pipe material, degree of damage, environmental conditions and operating pressure. 02 Technical System: Repair Method Library Based on Practical Testing After the rigorous testing of numerous projects, a mature and diverse non-digging repair technology system has been established. Each of these techniques has its own applicable scenarios and advantages, just like various surgical methods mastered by an experienced doctor. Overview of Main Non-Digging Repair Technologies Depending on whether the pipe damage is overall or localized, the repair techniques can be mainly classified into two categories: overall repair and local repair. · Overall repair: Addressing structural defects of the pipeline · Technical representative: Ultraviolet light in-situ curing method, spiral winding liner method, pipe liner coating method, thermoplastic molding close adhesion technology. · Core principle: A completely new and highly-strength "in-pipe in-pipe" structure is formed inside the old pipeline. · Practical value: Applicable to situations where pipelines are aging, severely corroded, or have multiple damages. It can solve the problems of the entire pipeline in one go, and the lifespan after repair can be as long as 50 years. · Local repair: For point-like defects in the pipeline · Technical representative: Local resin curing method, stainless steel double expansion ring method, stainless steel quick locking method. · Core principle: Only precisely reinforce and seal the damaged areas of the pipeline. · Practical value: The system is highly flexible, efficient and cost-effective, making it particularly suitable for dealing with sudden pipe ruptures or interface leaks. In the face of complex situations, experienced teams often adopt a "combined approach". For instance, in a river-crossing pipe repair project in Huadu District, Guangzhou, an innovative "large flow drainage + triple leak sealing technology + CIPP inverted lining" combined solution was adopted. This successfully repaired a 194-meter-long large-diameter river-crossing sewage pipe and set a regional record. 03 Overcoming Challenges: Classic Practices in Complex Scenarios True experience is accumulated through dealing with extreme challenges. The following several typical cases demonstrate how to utilize profound technical expertise to solve complex problems. Case One: Breakthrough in the Restoration of Deeply Buried Large-Diameter Long-Distance Pipelines In Dongheng River of Jiangyin City, a sewage pipeline with a burial depth of 15 meters, a pipe diameter of DN1000, and a single repair length of 209 meters is facing repair challenges. Traditional excavation methods are costly and have a significant impact. Solution: The team adopted the highly elastic ultraviolet light curing technology. Using custom high-elastic glass fiber hoses and high-power ultraviolet curing equipment, through precise processes, a high-strength inner lining layer with a thickness of up to 10 millimeters was formed. This successfully overcame the repair challenges of "deep burial + large pipe diameter + long distance", and achieved the first such project in the country. Case 2: Repair of continuously blocked large-capacity river-crossing pipeline In the New Ya area of Guangzhou, a DN1200 sewage main pipe that runs along the New Street River suddenly developed a structural defect, and it is responsible for transporting a daily average of 70,000 cubic meters of large volume sewage. Solution: The project team did not opt for the traditional pipeline shutdown and excavation method. Instead, they developed a comprehensive solution of "non-invasive repair + large-flow water diversion". Firstly, by optimizing the drainage system, they achieved zero sewage leakage during the construction period, creating "dry land" conditions for the repair work. Subsequently, they employed the CIPP (Cathodic Protection In-Place Repiping) reverse lining process to complete the repair of 194 meters of pipeline in one go, ensuring the dual safety of river ecology and urban drainage. Case 3: Pipeline Replacement in Complex Terrain In the Yuling shale gas field, a section of the mountainous area gathering pipeline was damaged. The traditional excavation method required crossing farmland, mountains and streams, making the construction extremely difficult. Solution: The technical team innovatively adopted the non-invasive trenchless crossing method of "replacing pipes with pipes". Using continuous tubing as the traction carrier, they directly inserted it underground to replace the damaged sectio