PE piping for potable water is a replacement product for steel pipes and polyvinyl chloride drinking water pipes.
PVC water supply pipes can withstand certain pressures, typically requiring high molecular weight PE resins with good mechanical properties, such as HDPE resins. LDPE resins have poor rigidity, poor dimensional stability during molding and processing, and are difficult to connect, making them unsuitable for water supply pressure pipes. LDPE, especially LLDPE resins, have become common materials for producing drinking water pipes. LDPE and LLDPE resins have low melt viscosity and good fluidity, making them easy to process, thus offering a wide range of melt index choices, usually between 0.3-3g/10min.
Compared to traditional piping materials, HDPE pipe systems feature a range of characteristics:
1. Polyethylene pipe systems are connected using electric heat fusion.
2. Polyethylene has a low-temperature brittleness temperature, making it usable within a temperature range of -60 to 60°C. During winter construction, it is less prone to pipe cracking.
3. HDPE pipes are resistant to corrosion from a variety of chemicals, and the chemicals present in the soil do not degrade the pipes. Consequently, they are less prone to rotting, rusting, or electrochemical corrosion; in addition, they do not easily promote the growth of algae, bacteria, or fungi.
4. Excellent Flexibility: The flexibility of HDPE pipes allows them to be easily bent, which makes it possible to maneuver around obstacles by altering the pipeline direction. In many cases, the flexibility of the pipes can reduce the amount of fittings used and lower installation costs.
5. Low Hydrodynamic Resistance: HDPE pipes feature a smooth inner surface with a Manning coefficient of 0.009. The smooth surface and non-stick properties ensure that HDPE pipes have higher conveying capacity than traditional materials, while also reducing pressure loss in the pipeline and water transportation energy consumption.
6. Easy to Handle: HDPE pipes are lighter than concrete pipes, galvanized pipes, and steel pipes, making them easy to transport and install. This reduces the need for excessive manpower and equipment, meaning a decrease in installation costs for the project.
7. Various Construction Methods: HDPE pipes offer a range of construction techniques, including conventional excavation. Additionally, non-excavation methods such as jacking, directional drilling, lining, and pipe bursting are available. These options are ideal for locations where excavation is not permitted.
