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Attention of polyurethane insulation steel pipe construction

The basic problems that should be paid attention to in the construction of polyurethane insulated steel pipe have been the focus of many people. The function of heat preservation pipe is more critical. The important performance of heat preservation pipe can be seen in chemical, petroleum, aerospace, central air conditioning and heating systems. For the construction project of polyurethane insulated steel pipeline, there are many relevant details to be noted. But in the actual laying, the laying method should be selected according to the site environment. Different laying methods have different characteristics and basic precautions are also different. Let's take a look at the details that need attention in the construction process. Details to be noted in the project: First of all, the construction personnel must carefully check after entering the site, which is very important for the relevant inspection procedures before construction. Any unqualified equipment, insulation pipes and raw materials shall not be used. Secondly, in the construction and welding of polyurethane insulated steel pipe, it is also the key to the quality of the whole project. Therefore, we must pay attention to the fixed support, pipeline welding and other processes, which directly affect the quality and effect of the whole insulation project in the later stage, and also directly determine the service life of the whole pipeline. Third, under the pressure standard, attention should be paid to the pipeline pressure. This step should be divided into two parts. First of all, the pressure can be increased if there is no leakage in the process of pressure stabilization. A hammer of standard weight is then used to tap the weld for leaks. Finally, adjust the pressure in the polyurethane insulation pipe to the working pressure range. If there is no leakage within half an hour, it is qualified. Fourth, we should know that this polyurethane insulated steel pipe is directly laid underground, usually these projects are hidden projects. If there is a little carelessness or careless completion acceptance in the construction or inspection process, faults or other phenomena may occur frequently in the later use and operation process. Even after the construction of polyurethane insulated steel pipe, it is necessary for relevant units to send special personnel for strict and serious acceptance inspection. Fifthly, no matter which polyurethane insulation steel pipe construction method is selected, attention shall be paid to the quality of the pipe, without cracking, layering, etc. the most important thing is to ensure that the joint of the pipe has the required waterproof, sealing and integrity. Due to the different materials of heat preservation pipes, pipe fittings and joints produced by different manufacturers, the melt flow rate of materials will be different. If the melt flow of the outer protective layer of the joint does not match the melt flow of the material used in the adjacent straight pipe or pipe fitting, the welding quality will be affected, thus affecting the sealing performance of the outer protective layer of the joint. Therefore, accessories from the same manufacturer should be used as much as possible. When working pipes are made of different materials and wall thicknesses, local stress concentration will occur, so it is necessary to design and check their strength.