Advantages and disadvantages of PE, PPR and PVC pipes and their applications

With the development of science and technology, the rapid development of the petrochemical industry, in the engineering of water supply and drainage systems more and more industries use plastic pipes instead of the conventional use of cast iron pipes, galvanized pipes, plastic-lined steel pipes and other materials. Compared with traditional pipes, plastic pipes have significant advantages such as light weight, corrosion resistance, low resistance to water flow, energy saving, easy and rapid installation and low cost, which are favored by the pipeline engineering community. Moreover, the design theory and construction technology of plastic pipes in construction have been greatly developed and perfected, and rich practical experience has been accumulated, prompting plastic pipes to occupy a considerable position in the construction of water supply and drainage piping projects, and forming an unstoppable development trend.

1. Three materials material composition, parameter analysis

PE pipe: Polyethylene, or PE for short, is a thermoplastic resin made by polymerization of ethylene, which has excellent resistance to industrial chemicals. PE pipes and their raw materials are strictly classified according to their long-term hydrostatic strength, and are divided into five grades: PE32, PE40, PE63, PE80 and PE100. PE80 and PE100 are mostly used in water supply and natural gas systems, and can be produced in large diameter pipes. The pressure grade is from 0 to 1.0MPa.

PVC pipe: PVC, the full name of which is “Polyvinylchlorid”, or PVC for short, is mainly composed of polyvinyl chloride, with other ingredients added to enhance its heat resistance, toughness, ductility and so on. Its specifications range from De16 to De630, and is divided into three kinds of pipes for water supply, water supply, and line. The pressure level is 0~1.6MPa.

PPR pipe: the full name is III random polypropylene pipe, from the propylene monomer Propylene and ethylene monomer Ethene polymerization of copolymer (Poly Propylene Random Copolymer), is a new energy-saving and environmentally friendly plastic products with the international level in the 1990s. Its specifications from De20 to De110, used in domestic water supply, hot water, pure drinking water project. The pressure level is 0～2.5MPa.

2,The advantages and common points of the three materials

（1）Advantages of PPR water pipe
PP-R pipe has the characteristics of light material, good strength, corrosion resistance and long service life in addition to the general plastic pipe, but also due to its own characteristics of non-toxic (the molecule contains only two elements of carbon and hydrogen, will not cause any toxic side use to the human body, is a well-deserved environmental health materials), non-rust, non-scaling (smooth inside and outside walls, with strong corrosion resistance, and little resistance to the flow of liquid flow) ) heat-resistant, frost-proof, heat preservation, waste can be recycled and other advantages, therefore, can be used as hot and cold water pipes, pure water pipes and drinking water pipes, etc., but also has the following main features.
①Heat-resistant, heat preservation, an energy-saving product.PP-R pipe Vicat softening temperature is 131.3℃, the highest use temperature is 95℃, the long-term (50 years) use temperature is 70℃. The thermal conductivity of the product is 0.24W/m℃, which is only 1/200 of the thermal conductivity of steel pipe, and it has excellent energy-saving effect for hot water pipe insulation;
②Easy and reliable installation, using hot fusion connection, a joint connection can be completed in a few seconds, and the connection with metal pipes and water apparatus uses high-quality metal nickel-plated inserts, safe and reliable.
③Easy to recycle and use

（2）Advantages of PE water pipeline
①PE pipe material is non-toxic, non-corrosive, non-scaling, which can effectively improve the water quality of the pipe network; chemical corrosion resistance, resistance to internal, external and microbial corrosion, corrosion resistance and health; PE pipe has good resistance to water hammer pressure, the fusion joint integrated with the pipe and the effective resistance of PE pipe to underground movement and end load, greatly improving the safety and reliability of water supply.
②It is easy to form a completed closed impermeable system by butt welding and electrofusion welding. When laying along the trench, it can reduce the amount of trench excavation and reduce the amount of fittings.
③Light weight and easy to install and handle; the tube angle can be processed at will.
④The strong abrasion resistance and excellent hydraulic properties allow buried pipes to be laid without the need for outer protection. It can be applied to earthquake and mining soil settlement areas, and can also be laid in river bottoms by the sinking method.
⑥Good environmental adaptability and frost resistance. Can be used for indoor and outdoor water supply pipes.
⑦Long service life, with a service life of more than almost 50 years.
⑧Easy to recycle and use.

（3）Advantages of PVC pipes
①In the production of general-purpose resins, PVC resins consume the lowest amount of ethylene and have the lowest production costs. The domestic production of PVC requires 0.5314 tons of ethylene per ton, while the average consumption of ethylene per ton of polyethylene 1.042 tons, the domestic consumption of ethylene per ton of PVC resin is about 50% less than the consumption of polyethylene. And the production of PVC with raw materials chlorine, is an important way to balance the production of caustic soda to produce chlorine, caustic soda is a very important raw material essential to the national economy. In addition, from the point of view of plastic products, PVC is compatible with various additives, and a large number of inexpensive fillers can be added to the production of pipes, so that production costs are greatly reduced.
②PVC pipe has good mechanical properties and has excellent corrosion resistance, light weight during use, easy installation, no maintenance, role of well-processed PVC pipe, service life of up to 50 years, etc.. Therefore, PVC pipe is a good plastic product with low production cost, high strength and corrosion resistance.
③Connection method – bonding, easy and fast.
④Easy to recycle and use.

All three materials can be used in domestic water supply systems, process circulating water systems, and general water supply systems.

3,Comparison of the disadvantages of the three materials

（1）PPR给水管道缺点
①Few pipe specifications and types of fittings. Fittings and valve types are not complete, and there is the problem of inconvenient connection with metal doors. Large-size pipe currently has a maximum of Dn160, with no larger specifications. There is a large variation influenced by temperature.
②Stiffness and impact resistance are worse than metal pipes and are easily damaged.
③The linear expansion coefficient of the tube is large.
④Poor UV resistance. Under the long exposure to sunlight and long time in the ultraviolet environment, PPR pipes are prone to aging, which reduces the service life.

（2）PE Disadvantages:
① PE cost is high, the pipe now with the continuous promotion of the price has been acceptable, but the price of fittings is still too high.
② PE cannot be used for hot water piping network.
③Hot fusion welding requires high pressure and long cooling time.
④It is prone to aging when exposed to outdoor sunlight.

（3）Disadvantages of PVC piping.
①Few pipe specifications and types of fittings. Incomplete types of fittings and valves, with the problem of inconvenient connection with metal doors.
②Stiffness and impact resistance are worse than metal pipes and are easily damaged.
③The buried connection has a low compressive lightness and is prone to fracture.
As mentioned above, these three kinds of pipes are widely used in water supply systems (steel skeleton plastic composite pipes are used in fire water supply systems), and PPR pipes can be used for hot water pipes. PE pipes are used for outdoor large diameter water supply network.

4,Comparison of three types of pipe connections

PE: When DN≤63, use injection molded hot melt socket connection or hot melt butt joint; when DN≥75, use hot melt butt joint connection or electric melt socket connection; when connected with different materials, use flange or fillet connection.
PPR: Injection molded hot melt socket connection; flange or fillet connection when connecting with different materials.
PVC: special adhesives are used for socket bonding, and flange or fillet connections are used when connecting with different materials.
In the case of pipe diameter greater than or equal to 75mm, PE is preferred in terms of cost (higher price of fittings). outdoor pipes are generally larger in diameter, so PE is mainly used for outdoor pipe networks.

5,Comparison of the aesthetic aspects of the three types of pipes

PE is mainly available in black and black with blue stripes (with UV resistance).
PPR is available in white and gray.
PVC is mainly white and blue in today’s market.
In terms of visual aesthetics, PPR pipes or PVC pipes are preferred for indoor plumbing.

6、Summary

PE pipes are used for outdoor water supply network, PPR pipes are used for indoor water supply and hot water network, and PVC pipes can be used for indoor cold water.
JWELL Machinery provide the full solution of PE,PVC,PPR pipe extrusion machine,have many customers all over the world.

Contact：Michelle Jiang/Andrew Shan
Mail：[email protected]/[email protected]
Phone/Whatsup/Wechat：+86 18851210802/ +86 188 5120 1053
Website：www.jwellchina.com