The direct burial of polyurethane direct buried thermal insulation pipes in recent ten years has been rapidly developed in China, and has become the main laying method of heating pipe network. The direct burial of the so-called polyurethane direct buried insulation pipe is to directly bury the polyurethane direct buried insulation pipe in the soil without the need to lay pipes in the construction trench.
Compared with trench laying, direct buried polyurethane insulation pipe has the following advantages:
1. There is no need to build trenches, the amount of earthwork and civil engineering is small; the pipeline is prefabricated, the amount of on-site installation is small, and the construction progress is fast, so the investment cost of the heating pipe network can be saved.
2, small footprint, easy to coordinate with other underground pipelines and facilities. This advantage is more obvious when the old city area, the streets are narrow, and the underground pipelines are densely packed.
3, polyurethane direct buried insulation pipe is tight, water is difficult to infiltrate between the insulation material and the steel pipe, the pipe is not easy to corrode. According to foreign materials, it is believed that the service life can be guaranteed for more than 50 years, which is much higher than that of the trench.
4. As a thermal insulation material, polyurethane has a small thermal conductivity, and the heat loss of the heating pipe is less than that of the trench, and the heat transfer efficiency is high.
5, polyurethane direct buried insulation pipe structure is simple, factory prefabrication, easy to ensure the quality of the project.
It is precisely because of the above various reasons that the polyurethane direct buried insulation pipe manufacturing industry has developed rapidly in China, and there will be more room for development in the future.
During the "Twelfth Five-Year Plan" period, the annual demand compound growth rate of directly buried thermal insulation pipes is expected to exceed 60%. The demand for China's external wall insulation market will erupt in the next three years or will raise the global MDI industry operating rate to 83%. The direct buried insulation pipe material excels in heat insulation, water absorption resistance, tensile strength and compression resistance. We expect that the proportion of direct buried insulation pipe in insulation materials will increase from 10% in 2011 to 36% in 2015. The annual compound growth rate is expected to exceed 60%.
The external wall insulation market from 2011 to 2015 is expected to bring about 500,000 tons of new demand for MDI (the demand for 2011-2015 is 3, 5, 8, 13, 210,000 tons respectively)
The outbreak of demand for China's external wall insulation market will accelerate the global MDI industry's operating rate in the next three years. It is expected that the global industry operating rate will increase from the current 74% to 83% by 2015, and the industry's upward trend will be strengthened.
We believe that the external wall insulation industry will usher in an excellent development opportunity. The direct buried insulation pipe is expected to resume explosive growth, and the annual demand compound growth rate will exceed 60%.