What is UHMWPE pipe?
UHMWPE pipe, also known as ultra-high molecular weight polyethylene pipe, is a pipe formed by continuous extrusion of ultra-high molecular weight polyethylene (UHMWPE) resin with a molecular weight greater than 2.5 million. Under the conditions of strong corrosion and high wear, the service life is 4-6 times that of steel pipes, which fully demonstrates the advantages of “energy saving, environmental protection, economy and high efficiency”.
Properties of UHMWPE pipes
|
Type |
Item |
UHMW-PE |
|
Physical Properties |
Relative molecular weight/ million |
2-3 |
|
Density/ (g/cm3) |
0.945-0.975 |
|
|
Grain size/ mesh |
40-200 |
|
|
Mechanical Properties |
Tensile yield stress/ MPa |
≥20 |
|
Fracture Extensibility % |
300-400 |
|
|
Flexural Modulus/ MPa |
600 |
|
|
Impact Strength/ (KJ/m) |
>140 |
|
|
Rate of Wear % (23±2) ℃ |
≤0.4 |
|
|
Thermal Properties |
Melting Point/ ℃ |
136 |
|
Distortion Temperature/ ℃ |
85 |
|
|
Thermal Conductivity/ [w/(m.v)] |
8.5 |
|
|
Electrical Properties |
Mass Resistivity/ (cm) |
10 |
|
Punch Through Voltage/ (Kv/mm) |
50 |
|
|
Dielectric Constant |
2.3 |
Advantages of UHMWPE Pipes:
- High wear resistance: 4 times of steel pipe, 3 times of common PE pipe and 4 times of nylon pipe. It is proved that UHMWPE pipe is a common wear-resistant pipe for small particle slurry transportation.
- High corrosion resistance: UHMWPE is saturated intermolecular structure, so its chemical stability is extremely high and can resist various corrosive media (acid, alkali, salt) and organic solvents in the environment.
- Weather resistance and aging resistance: UHMWPE pipes have good weather resistance and aging resistance. Because there are very few unsaturated groups in the molecular chain of UHMWPE and the molecular weight is large, the pipe can maintain more than 70% of its mechanical properties for up to 50 years even after about 70% use.
- High flexibility: The elongation at break can reach more than 400%, and there is a large bending during construction, and the subsidence of the earth’s crust can elongate up to 3 times without breaking.
- High impact resistance: The impact resistance and impact energy absorption of ultra-high molecular weight polyethylene (UHMWPE) pipes rank first among plastics, and they are not easy to crack regardless of external force or internal pressure fluctuations. The impact strength is 10 times that of nylon 66 and 4 times that of polyethylene PE100.
- Good energy-saving effect: The friction coefficient is 0.07-0.11 , the roughness is only 1/6 of the new steel pipe, the circulation capacity is more than 50% higher than that of steel pipe, and the inner diameter of steel pipe can be reduced by about 15% compared with that of steel pipe.
- Easy to install: The weight of UHMWPE pipe is 1/8 of steel pipe, which greatly reduces the installation cost. The pipe body is directly flanged and connected with flange butt, no need to add seals; it can also be inserted into hot melt welding, with high interface strength and easy operation.
- Long service life: Under the same operating conditions, the wear resistance of UHMWPE pipes is 4 to 7 times higher than that of Q235 steel pipes, or 10 times that of HDPE (PE100) pipes, and the service life of UHMWPE pipes is longer under most operating conditions Much longer.
4 common identification methods:
1. Weight
The density of UHMWPE products is between 0.93-0.95g/cm3, which can float on water. If it is not pure UHMWPE material, the product will sink into water.
2. Temperature
Good quality UHMWPE products will not melt and deform at 200°C, but will become soft. Inferior UHMWPE products will deform at 200 °C.
3. Visibility
The surface of good-quality UHMWPE pipe is smooth, neat, black and bright, and the cross-sectional density is very uniform. The surface color of inferior UHMWPE pipes is dull, and the cross-sectional density is uneven.
4. UHMWPE Pipe Ends
Good UHMWPE pipe ends are smooth, uniform, and have good roundness and verticality, but poor-quality UHMWPE pipes will crack and peel off after the pipes are heated.
