HDPE (High Density Polyethylene) has the unique advantages of being heroic in pipelines. Its flexibility, corrosion resistance, low temperature resistance, weldability, and non-excavation directional drilling have expanded its application fields, especially in Among the commonly used plastic materials, rapid crack transmission resistance is the best, making it the material of choice for gas pipelines.
Since the 1960s, HDPE gas pipes have also been widely used in pipelines due to their excellent performance.
A good pipeline should not only have good economy, but also have a series of advantages such as stable and reliable interface, impact resistance, crack resistance, aging resistance, corrosion resistance, etc. Compared with traditional pipes, HDPE piping system has the following: Series advantages:
1. Reliable connection: the polyethylene pipe system is connected by electric heating, and the strength of the joint is higher than the strength of the pipe body.
2. Good low-temperature impact resistance: The low-temperature embrittlement temperature of polyethylene is extremely low, and it can be used safely in the temperature range of -60-60℃. During construction in winter, because the material has good impact resistance, the pipe will not be brittle.
3. Good stress crack resistance: HDPE has low notch sensitivity, high shear strength and excellent scratch resistance, and its environmental stress crack resistance is also very outstanding.
4. Good chemical resistance: HDPE pipes can withstand the corrosion of a variety of chemical media, and the chemical substances in the soil will not cause any degradation to the pipes. Polyethylene is an electrical insulator, so it will not rot, rust or electrochemical corrosion; in addition, it will not promote the growth of algae, bacteria or fungi.
5. Anti-aging and long service life: The polyethylene pipe containing 2-2.5% evenly distributed carbon black can be stored or used outdoors for 50 years without being damaged by ultraviolet radiation.
6. Good wear resistance: The comparison test of the wear resistance of HDPE pipes and steel pipes shows that the wear resistance of HDPE pipes is 4 times that of steel pipes. In the field of mud transportation, HDPE pipes have better wear resistance than steel pipes, which means that HDPE pipes have a longer service life and better economy.
7. Good flexibility: The flexibility of HDPE pipeline makes it easy to bend. In engineering, obstacles can be bypassed by changing the direction of the pipeline. In many cases, the flexibility of the pipeline can reduce the amount of pipe fittings and reduce installation costs.
8. Small water flow resistance: HDPE pipe has a smooth inner surface, and its Manning coefficient is 0.009. The smooth performance and non-adhesive properties ensure that HDPE pipes have a higher conveying capacity than traditional pipes, and at the same time reduce the pressure loss of the pipes and the energy consumption of water transmission.
9. Convenient handling: HDPE pipes are lighter than concrete pipes, galvanized pipes and steel pipes. It is easy to handle and install. Lower manpower and equipment requirements mean that the installation cost of the project is greatly reduced.
10. A variety of new construction methods: HDPE pipelines have a variety of construction technologies. In addition to traditional excavation methods, a variety of new non-excavation technologies such as pipe jacking, directional drilling, and liner can also be used. It is a better choice for some places where excavation is not allowed. Therefore, HDPE pipelines are more widely used.