HDPE double-wall corrugated drainage pipeline is an important facility for the normal operation of the city, but due to serious road overload, improper construction of underground adjacent pipelines and other reasons, the internal collapse of the water supply and drainage pipeline is serious, hindering its normal drainage function. In order to solve the above problems, we have designed a new in-pipe grouting robot which is applied to the internal collapse repair technology of HDPE double-wall corrugated pipeline. Compared with the existing drainage pipeline repair methods, it has the characteristics of high construction efficiency and low construction requirements, and the repair and shaping operation can be carried out in the area where the underground pipe condition is more complex.