Directly buried prefabricated insulation pipe is a type of cold insulation and energy-saving pipeline, commonly used in insulation engineering in urban centralized heating, petroleum, chemical, refrigeration and other fields. So, how is this type of pipeline made? Firstly, the working steel pipe layer of the directly buried prefabricated insulation pipe. According to the design and customer requirements, seamless pipes, spiral welded pipes, or straight seam welded pipes are generally selected. These steel pipes need to undergo advanced shot blasting and rust removal processes