Polyethylene (PE) piping for water supply is a replacement product for steel pipes and polyvinyl chloride (PVC) drinking water pipes.
PE piping can withstand certain pressures, usually requiring high molecular weight PE resins with good mechanical properties, such as HDPE resins. LDPE resins have poor rigidity and 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, typically between 0.3-3g/10min.
Compared to traditional piping materials, HDPE pipe systems offer a range of features:
1. The 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 can withstand corrosion from a variety of chemical substances, and the chemicals present in the soil will not degrade the pipeline. Therefore, it is less prone to rot, rust, or electrochemical corrosion; in addition, it also does not easily promote the growth of algae, bacteria, or fungi.
4. Excellent Flexibility: The flexibility of HDPE pipes allows them to be easily bent, enabling engineers to navigate around obstacles by changing the pipe's direction. In many cases, this flexibility can reduce the need for fittings and lower installation costs.
5. Low Flow Resistance: HDPE pipes feature a smooth inner surface with a Manning coefficient of 0.009. The smooth surface and non-adhesive properties ensure that HDPE pipes have a higher conveying capacity than traditional pipes, while also reducing pressure loss in the pipeline and water conveyance energy consumption.
6. Easy Handling: HDPE pipes are lighter than concrete pipes, galvanized pipes, and steel pipes, making them easy to transport and install. This requires less labor and equipment, resulting in reduced installation costs for projects.
7. Various Construction Methods: HDPE pipes offer a range of construction techniques, including conventional excavation, as well as non-excavation methods such as jacking, directional drilling, lining, and bursting. This is an excellent choice for locations where excavation is not permitted.
