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Trenchless Repair Technology and Application of Urban Sewer System

With the constant expansion of urban construction, the rapid development of urban underground pipeline becomes complex. Due to disrepair, improper maintenance and management and other factors, the urban sewer appears varying degrees of damage phenomenon. Therefore, the urban underground sewer repair becomes an urgent problem. This article introduces the methods of trenchless pipe rehabilitation technology and developments at home and abroad. It also elaborates the technology design points of stainless steel foam cylinder repair, combining with engineering examples.