Common problems and solutions in the construction of directly buried thermal insulation pipes

Common problems and solutions in the construction of directly buried thermal insulation pipes The direct buried insulation pipe is foamed by chemical reaction of high-function polyether polyol composite material and polymethyl polyphenyl polyisocyanate as raw materials. Directly buried thermal insulation pipes are used for thermal insulation and cold insulation projects of various indoor and outdoor pipes, central heating pipes, central air conditioning pipes, chemical, pharmaceutical and other industrial pipes. Overview Since the birth of polyurethane composite materials in the 1930s, the polyurethane foam insulation pipe has been rapidly developed as an excellent thermal insulation material, and its application range has become more and more extensive. It is widely used in various pipelines such as heating, cooling, oil transportation, and steam transportation. Common problems and solutions in the construction of directly buried thermal insulation pipes This phenomenon generally occurs in autumn and winter or in the morning construction, because the temperature suddenly drops or the temperature is low. It can be solved by increasing the ambient temperature and the temperature of the black material. Generally, the temperature of the black material is raised to 30-60°C, and the ambient temperature is raised to 20-30°C. This phenomenon generally occurs in spring and summer or during construction at noon, because the temperature suddenly rises and the temperature is too high. The black material can be cooled with cold water or placed outdoors at night for natural cooling to avoid direct sunlight. The foam strength of the directly buried insulation pipe is small and the foam is softer. This phenomenon is caused by the imbalance of the ratio of black and white materials. The proportion of black materials can be appropriately increased (1:1-1.05). Be careful not to make the proportion of black materials too large, otherwise, it will cause The foam becomes brittle, which also affects the performance of the foam. Direct buried insulation pipe has become a relatively mature advanced technology in some developed countries abroad. In the past ten years, my country’s heating engineering and technical personnel are promoting the development of domestic pipe network laying technology to a higher level by digesting and absorbing this advanced technology. The practical results over the past ten years have fully proved that the laying method of directly buried thermal insulation pipeline has many advantages compared with the traditional trench and overhead laying. The direct-buried thermal insulation pipe is closely combined with the steel pipe for conveying the medium, the high-density polyethylene outer casing, and the rigid polyurethane foam insulation layer between the steel pipe and the outer casing. This is also the internal driving force for the rapid development of polyurethane thermal insulation direct buried pipes in my country’s heating engineering. Post time: Oct-17-2022