Polyurethane directly buried thermal insulation pipe for heating is a combination of steel pipe for conveying medium, anti-corrosion outer steel pipe and rock wool filled between steel pipe and outer steel pipe. It can also be compounded by graphite, silicon calcium tile shell and polyurethane foam filled. Steel casing (steel casing) burying technology is a new technology of waterproof, leak-proof, anti-seepage, anti-pressure and fully enclosed burying. It is a major breakthrough in the use of direct burying technology in areas with high groundwater level. The primary problem of the protection pipe of the directly buried pipeline is the reliability of tight waterproofing. In addition, it must have good mechanical strength. The steel casing adopts welding connection due to high strength, and the reliability of waterproof sealing performance is very high. In addition, its high temperature resistance is also unmatched by other external protection pipes. In areas with high groundwater level, in order to ensure that the groundwater does not affect the normal operation of the directly buried steam pipeline, the outer protective layer adopts a solid and closed steel pipe shell. Insulation pipeline is widely used in liquid, gas pipe network, chemical pipeline insulation engineering petroleum, chemical, central heating heating network, central air conditioning ventilation pipeline, municipal engineering, etc. High temperature prefabricated direct buried insulation pipe is a kind of good insulation performance, plus safe and reliable, low cost of the project buried prefabricated insulation pipe. It effectively solves the problems of insulation, sliding lubrication and waterproof of exposed pipe ends of prefabricated directly buried insulation pipes for high temperature transmission of 130 ℃-600 ℃ in urban central heating. High temperature prefabricated directly buried insulation pipe not only has the advanced technology and practical performance which is incomparable to the traditional trench and overhead laying pipeline, but also has significant social and economic benefits, which is also a powerful measure for heating energy saving.
