Thermoplastic composite pipes have excellent mechanical properties and cost advantages. It generally consists of 3 layers of structure, namely the polymer inner lining layer, the reinforcing layer and the outer jacket layer:
· Inner lining layer:
The inner layer plastic plays the role of corrosion resistance and fouling resistance, and its materials are mostly high-density polyethylene (HDPE), polyvinylidene fluoride (PVDF) or other modified polymer materials.
· Reinforcing layer:
The reinforcing layer is an intermediate layer, which increases the hoop stiffness of the pipe and improves the compressive strength by braiding/winding the reinforcing material on the polymer inner lining layer. Common reinforcing materials can be divided into metals and non-metals. Metals are mainly steel wires and steel belts; non-metals include glass fibers, aramid fibers, high molecular polyethylene fibers and fiber prepreg tapes.
·Jacket layer:
The jacket layer mainly plays the role of anti-scratch, protecting the reinforcement layer from damage, and isolating external corrosion damage. Common outer sheath materials are polyvinylidene fluoride (PVDF) and polyetheretherketone (PEEK).
Advantages of TCP Pipes
TCP pipes can not only withstand high working pressures, but also maintain the light weight, corrosion resistance and high flexibility of plastic pipes. Compared with the widely used steel rigid pipes and flexible pipes, TCP has the following special advantages:
· Corrosion resistance:
The inner and outer pipe walls of TCP are made of polyethylene and other polymers. This material has good anti-corrosion properties. The material of the inner and outer layers can be modified or a special functional layer can be added according to the needs of the application. It is suitable for a variety of corrosive media and Various corrosive environments.
· Strong conveying capacity:
The inner wall of the TCP is smooth and the flow resistance is small, which can maintain the conveying capacity for a long time and reduce the maintenance cost of the pipeline.
·Convenient construction:
TCP can be prepared into coiled tubing, and the common length can range from 20m to 2000m, which not only facilitates and quick installation, but also greatly reduces the number of joints and the hidden danger of leakage. TCP has strong tensile ability and can withstand large drag force during installation. Its high flexibility also ensures the self-compensation ability during the installation process and reduces the installation cost.
Technical Data of HDPE TCP Pipes:
| Molecular | ≥300 000 |
| Density | 0.960 g/cm3 |
| Tensile breaking strength | ≥28 Mpa |
| Longitudinal contraction rate of return | ≤3% |
| Breaking elongation | ≥500% |
| Resistant to corrosion | good |
| Tensile strength | ≥28Mpa |
| Static hydraulic strength | 1)20℃,cycle stress 12.4Mpa,100h,no break,no leakage. 2)80℃,cycle stress5.5Mpa,165h,no break,no leakage 3)80℃,cycle stress5.0Mpa,1000h,no break,no leakage |
| MFR(190℃,5kg,)g/10min | ≤25% |
| Oxidation induction time (200℃)min | ≥20 |