When many users choose PE pipes, they are often easy to make mistakes due to insufficient understanding of it. They don’t know whether to use random copolymerized polypropylene pipes or polyethylene pipes for water supply projects in construction. What is the difference between them? Woolen cloth? Let me introduce it to you.
The main points are as follows:
In drinking water, PE is generally used as cold water pipe; PPR (special hot water material) can be used as hot water pipe; there are also PPR (cold water material) used as cold water pipe;If it is a hot water pipe, of course PPR is better; (if it is a drinking water pipe for home decoration, then there is no need to distinguish, basically PPR is used more than PE)If you are doing cold water pipes, you can refer to the following differences:
1. Comparison of temperature resistance between PPR water pipe and PE water pipe.
Under normal use, the PE water pipe has a stable temperature of 70°C and a temperature of -30°C. That is to say, in such a temperature range, long-term use of PE water pipes is safe and reliable.
Under normal use, the PPR water pipe has a stable temperature of 70°C and a temperature of -10°C. It also shows that in this temperature range, long-term use of PPR water pipes is also safe and reliable. It is concluded that PE water pipes have the same high temperature resistance as PPR water pipes. However, PE water pipes are better than PPR water pipes in terms of low temperature performance.
2.the difference between PE water pipes and PPR water pipes in terms of hygiene
The main chemical molecular component of PE water pipe is polyethylene. Readers who have studied organic chemistry know that the composition of this product is two carbon atoms combined with five hydrogen atoms, one of which is combined with a carbon atom by a double bond, and then ethylene The single molecule of the polymer is polymerized in a certain way, and such a product is a polyethylene product. So what is the PPR water pipe? The main component of PPR water pipe is propylene, that is, three carbon atoms are combined with seven hydrogen atoms, and one hydrogen atom is combined with a carbon atom with a double bond, and then the product formed after polymerization is a polypropylene product. Such products are almost the same in terms of hygiene and safety. The important thing is whether the raw materials used by the enterprise meet the requirements, not the difference between the two products. It is also unfounded to advertise that PE water pipes are more hygienic than PPR water pipes in newspapers. All qualified PE water pipes and PPR water pipe products must undergo sanitation testing (except for those fake and shoddy products). It is also a deception to consumers to say that PE water pipes are more hygienic and safer than PPR water pipes.
3. Elastic modulus
The elastic modulus of PPR water pipe is 850MPa. PE water pipe belongs to medium density polyethylene, and its elastic modulus is only about 550MPa. It has good flexibility and insufficient rigidity. It is used in the field of building water supply. Not beautiful.
Thermal conductivity: PPR water pipe is 0.24, PE water pipe is 0.42, which is nearly twice as high. If it is used in floor heating, this is its strong point. Good heat dissipation means that the heat radiation effect is better, but it is used in hot water pipes. The disadvantage is that if the heat dissipation is good, the heat loss will be large, and the surface temperature of the pipe will be higher, which is easy to burn.
4. Welding performance
Although both PPR water pipes and PE water pipes can be hot-melt welded, PPR water pipes are easier to operate, and the flanging of PPR water pipes is round, while the flanging of PE water pipes is irregular and easy to block; the welding temperature is also different, PPR water pipes are 260 ° C, PE water pipes The temperature is 230°C, and the special welding machine for PPR water pipes on the market is easy to over-weld and cause water leakage. In addition, because the PE water pipe material is easy to oxidize, special tools must be used to scrape off the oxide skin on the surface before welding, otherwise a truly integrated pipe cannot be formed, and the pipe is prone to water leakage, so the construction is even more troublesome.
5. Low temperature impact strength:
This point is the strength of PE water pipe material in terms of indicators. PPR water pipes are stronger than PE water pipes, and PE water pipes are more flexible than PPR water pipes. This is determined by the nature of the material, but it is meaningless to exaggerate the cold brittleness of PPR water pipes. , PPR water pipes have been used in China for more than ten years. Manufacturers have gradually reduced the hidden dangers caused by improper handling through effective packaging and strengthened publicity. Brutal handling and construction will also cause PE water pipes on the surface. Scratches and stress cracks; when used under low temperature conditions, any pipeline must be insulated, otherwise the volume expansion caused by freezing will cause the pipeline to freeze and crack. PPR pipe is an ideal pipe for drinking water pipes, and the outdoor environment is not as good as indoors. PE pipes are used, which is also an ideal material for water pipe main pipes.
6. Pipe size
The maximum size that can be made of PE pipe is dn1000, and the specification of PPR is dn160. Therefore, PE pipes are mostly used as drainage pipes, and water supply pipes are generally PPR.
Post time: Jun-30-2023