About the difference between HDPE pipe and PE pipe, is a question that is frequently asked. It seems simple, but few people say obviously, here we HDPE pipe manufacturers on the system to introduce you.
PE Pipe is a Polyethylene plastic pipe. As one of the most basic plastics, PE has excellent resistance to most chemicals used in life and industry. Common plastic bags and plastic wrap are PE.
PE pipe as a whole can be divided into: low-density polyethylene pipe (LDPE pipe), medium-density polyethylene pipe (MDPE pipe) and high-density polyethylene pipe (HDPE pipe) three kinds.
I. Low density polyethylene (LDPE)
Low density polyethylene is typically produced by elevated pressure polymerization with a density of 0.910-0.925g/cm3. The molecular structure of low-density polyethylene is a linear macromolecule with numerous branch chains. The branch chains of different lengths on the main chain affect the regularity of the arrangement of macromolecules, and the stacking is not tight, which hinders the crystallization of polyethylene, so the crystallinity is 55%-65%. Low density polyethylene has a low melting point, soft texture, tall branch chain gives it low viscosity at high shear rate in the process of processing and elevated melt strength during drafting, so it is extremely suitable for the film blowing process, mainly used in the production of agricultural film and heavy packaging film.
Ii. Medium Density polyethylene (MDPE)
Medium density polyethylene (MDPE) is controlled by A-olefin copolymerization under medium and low pressure with elevated efficiency catalyst.
(0.926-0.940q/cm3), the crystallinity of 70%-80%. Because of its numerous tall branch chains, the density and crystallinity decrease, so the medium density polyethylene has better flexibility and low temperature characteristics, tensile strength, hardness, thermal properties than high-density polyethylene. Because the polyolefin can increase the interwafer linkage chain of medium-density polyethylene crystal, its low speed cracking resistance and long-term mechanical strength retention are considerably improved compared with LDPE. Mdpe can be used in the production of pressure pipes, conveyor pipes, various containers and packaging films.
Iii. High Density polyethylene (HDPE)
High density polyethylene (HDPE) is produced by low pressure polymerization process. It is linear, with a density of 0.94-0.965q/cm3 and crystallinity of 80%-95%. It is a white powder or particle. Compared with low-density polyethylene, additional sub-branch chains are less, nearly linear structure, regular molecular arrangement, compact stack, so its crystallinity is elevated, density, relative molecular mass is more than one hundred thousand to hundreds of thousands, the range of melt flow rate is narrow. High density polyethylene has superior rigidity and toughness, excellent mechanical strength and heat resistance, as well as better depth resistance, steam permeability resistance. High density polyethylene has the lowest permeability, the strongest corrosion resistance and excellent stiffness among all kinds of polyethylene. It is mainly used in the production of various pressure pipes and injection products.
Therefore, HDPE pipe is a kind of PE pipe, but compared with ordinary PE pipe, the performance of HDPE pipe is better, which can be summarized as the following three points:
1. Different pressure bearing:
HDPE tube must bear a certain pressure, normally choose high molecular weight, excellent mechanical properties of PE resin, such as HDPE resin, the strength is ordinary polyethylene tube (PE tube) 9 times;
2. different wear resistance
Among all engineering plastics, HDPE's wear resistance is the crown jewel. The higher the molecular weight, the more wear-resistant the material, even more than numerous metal materials (such as carbon steel, stainless steel, bronze, etc.), ordinary PE wear resistance is only one tenth of HDPE;
3. different uses
In general,PE pipe (medium density polyethylene pipe) is suitable for transporting gaseous artificial gas, natural gas, liquefied petroleum gas, low density polyethylene pipe is a hose;
hDPE pipe (high density polyethylene pipe) is mainly suitable for transporting natural gas, municipal engineering water supply system, indoor water supply system of buildings, outdoor buried water supply system, residential district, factory buried water supply system, old pipeline restoration, water treatment project pipeline system, garden, irrigation and other fields of industrial water pipes.
HDPE pipe can be used as the replacement of traditional steel pipe and PVC drinking water pipe, ordinary PE pipe is not.
In summary, that is, the difference between PE tube and HDPE tube. I hope to help you.