Polyurethane direct buried seamless insulation pipe

       Polyurethane direct buried seamless insulation pipe has become a mature advanced technology in developed countries. China's heating engineering technicians have passed this research to promote this technology to promote the development of domestic pipe network technology to a higher level. Polyurethane direct-buried insulation tube is made of high-performance polyether polyol composition and multiple methyl polyphenyl polyisocyanate as raw materials, and then chemically foamed. It is widely used in indoor and outdoor pipelines and central heating. Pipe, chemical, pharmaceutical industry pipelines and other insulation, cold preservation projects. Polyurethane polyurethane direct buried seamless insulation pipeshould pay attention to the installation and explanation: 

1. It must be understood that the direct buried laying mode of the heating pipe is divided into two ways: make up for direct burial and no compensation for direct burial. In the design and construction, it is necessary to master the working principle, characteristics and application places of the two methods, so that the design should be rationally selected, and the construction is safe, reliable and economical. 
2. After the on-site inspection, the inspection will be carried out carefully. Before the construction, it is necessary to conduct research on the manufacturers of polyurethane directly buried insulation pipes. Refuse to use the unqualified insulation pipe. 
3. In the construction of polyurethane direct buried insulation pipe, welding is a key work to ensure the quality of the project, and it must be paid enough attention. 
4.  The construction quality of various well chambers directly affects the quality of the project and the service life of the pipeline, and the bracket is fixed. If the well is not well waterproofed, the parts will be damaged by water immersion. Therefore, construction should be carried out carefully to ensure the quality of the construction.  
5. to meet the pressure conditions, must pay attention to the pressure of polyurethane direct buried insulation pipe. First, the water was irrigated and drained, and then divided into two steps: no leakage within 10 minutes of voltage regulation. Strength test: After the pressure in the pipeline is raised to 1.5 times the working pressure; the weld is individually punched around the weld with a 1kg hammer; the tightness test: when the pressure in the pipe is reduced to the working pressure If there is no leakage within 30 minutes and the pressure drop cannot exceed 0.2 atmospheres, it is qualified; the pressure test record should be made according to the specifications.
6. Because the polyurethane direct buried insulation pipe is buried in the ground, when the project is accepted, the vast part is concealed. If the completion acceptance is not serious, the completion data will not be detailed, which will affect the future use.
7. The primary problem of the protection pipe of the direct buried pipeline is the reliability of tight waterproofing. In addition, it has good mechanical strength. The steel casing is welded by high strength, and the waterproof sealing performance is very reliable. In addition, its high temperature resistance is also Other external protection tubes are unmatched.

       In areas with high groundwater levels, in order to ensure that groundwater does not affect the normal operation of the direct buried pipeline, the outer protective layer is made of a strong, sealed steel casing. The so-called upper hydrophobicity is to pass the condensed water in the pipeline through the hydrophobic pipe inserted into the working steel pipe, and the condensed water in the water collecting tank utilizes the back pressure in the pipeline to discharge the condensed water from the upper part of the pipeline.