1. Corrosion resistance and long service life. In China's coastal areas, the groundwater level is high and the ground humidity is high. The seamless steel pipe must be anticorrosive and installed outside the male hammer. The service life is only 30 years, and the polyethylene pipe can withstand a variety of Corrosion of chemical media does not require anticorrosive treatment. It also does not promote the growth of algae, bacteria or fungi, and it can live up to 50 years.
2. Excellent physical properties. The performance of medium density polyethylene is between high density polyethylene and low density polyethylene. It not only maintains the stiffness and strength of high-density polyethylene, but also has good flexibility and creep resistance. Compared with high-density polyethylene, it has better hot-melt connection performance, which is beneficial to the installation of plastic pipes.
3. Large circulation capacity and good economic benefits. The inner wall of the polyethylene pipe is smooth and free from scaling. The absolute roughness ratio of polyethylene pipe surface is 1/20 of that of steel pipe. The flow rate of polyethylene pipe is about 30% more than that of steel pipe under the same diameter, same length and the same pressure. Compared with metal conduits, polyethylene conduits can reduce engineering investment by about 1/3, can be wound with small diameter coil tubing, and can further reduce engineering costs.
4. Good toughness and flexibility. PE pipe is a kind of high toughness pipe with an elongation at break of more than 500%. It has a strong adaptability to uneven settlement and dislocation of the pipeline foundation and good seismic performance. Therefore, it is most suitable for seismic danger zones and the practice of countries around the world. It has been proved that polyethylene pipe is the pipe with the best seismic performance. In addition, the flexibility of the PE pipe is that the PE pipe can be coiled, reducing a large number of connections. According to the requirements of the construction method, the direction of the PE pipe can be easily changed. During construction, the pipeline can be allowed to bypass the bending radius of obstacles, reducing the difficulty of construction.
5. Convenient connection, simple construction and various methods. The polyethylene pipe is light, easy to carry, easy to weld, and has few welds. When the pipe is long, the requirements for laying a polyethylene pipe groove in a spiral pipe are much lower than the requirements of a steel pipe groove. Welding. In addition, the immersed pipe method can be used for underwater laying, which greatly reduces the construction difficulty and engineering cost.
6. Good sealing performance The polyethylene pipe itself is welded, which essentially guarantees the consistency of the interface material and structure with the pipe body itself, and realizes the integration of the joint and the pipe. The tensile strength and burst strength of the interface are higher than those of the pipe body, and can effectively resist the hoop stress and axial stress caused by the internal pressure. Therefore, compared with rubber ring connection or other mechanical connections, the sealing performance is very good.
7. Convenient maintenance, non-stop water and gas maintenance and installation.
8. Good resistance to stress cracking: polyethylene pipes have different cross-section resistances with low notch sensitivity and high shear strength, and have outstanding resistance to environmental stress. Low temperature impact resistance: The low temperature brittleness temperature of polyethylene pipe is very low, and it can be used in the temperature range of -60 degrees Celsius. Good abrasion resistance. The wear resistance of polyethylene pipe is 4 times that of steel pipe.