Comparison of PE pipe and SRTP Steel Wire Reinforced pipe
PE pipe is the most commonly used water supply pipe at this stage. It can connect straight pipes with straight pipes, straight pipes with pipe fittings, and is easy to install. Good flexibility, can be integrated into various soil layers
Pipeline advantages:
1. Extraordinary corrosion resistance: Except for a few strong oxidants, it can withstand the corrosion of various chemical media; no electrochemical corrosion.
2. High-quality environmental sanitation characteristics: no heavy metal salt stabilizer is added during the production and processing of PE pipes, the raw materials are non-toxic, no fouling layer, and no bacteria grow, which effectively solves the secondary environmental pollution of domestic water in big cities.
3. High-quality engineering construction characteristics: the pipeline is lightweight, the welding process is simple, the engineering construction is convenient, and the comprehensive cost of the engineering project is low.
4. Good impact resistance: PE pipe has good toughness, high impact resistance and compressive strength, and heavy objects immediately press through the pipeline, which is not easy to cause the pipeline to break.
5. Reliable connection characteristics: The compressive strength of the hot-melt or electro-melt interface of the PE pipe is higher than that of the pipe itself, and the joint is not easy to be broken due to the movement of the soil layer or the effect of live load.
6. Long-term service period: Under the condition of rated temperature and working pressure, PE pipes can be safely used for more than 50 years.
Defects of PE pipe compared with Steel Wire Reinforced pipe: insufficient rigidity, not suitable for application in the sun exposure place.
The steel mesh frame plastic composite pipe is made of steel wire coiled mesh as the frame raising body of the polyethylene plastic pipe, with polyethylene (HDPE) as the matrix, and the surface layer of high-density polyethylene is inseparably connected together, so that it has high quality and strong strength. Therefore, it is more suitable for pipeline applications such as long-distance water supply and gas transmission in mountainous areas.
Pipeline advantages:
1. Since the structure of the two raw materials, steel and plastic, is composite, it is not easy to generate rapid stress that is difficult for plastic pipes to overcome.
2. The weight is light, and the pipeline connection adopts electric heating fusion joint, which has strong anti-axial pressure working ability.
3. It has the characteristics of compressive strength, stiffness and impact resistance that exceed ordinary pure plastic pipes, similar to the low linear expansion coefficient and creep resistance of steel pipes;
Steel Wire Reinforced pipe defects:
Since the inner lined steel mesh cannot be butted and hot-melted, special hot-melt joints need to be used for connection, which increases the construction budget and cost, and the joint between the pipe and the hot-melt joint is very easy to break due to its high stiffness. Therefore, it is suitable for use in mountainous areas and areas with hard soil layers, while areas with loose soil layers or high moisture content should be used as little as possible.
Introduction of PE water pipe ring stiffness
Ring stiffness refers to the external compressive load of the polymer or polymer composite pipe, the full name is ring bending stiffness, which is defined as the measurement of the resistance of the pipe to annular deformation. The experimental method or the calculation method can be used. The load on the PE water supply pipe has internal working pressure and external working pressure. Generally, the stress formed by the internal pressure is the key factor that causes the damage of the PE water supply pipe. The form of failure is excessive deformation and cracking caused by tensile stress in the pipe wall.
The external pressure that the PE water supply pipe needs to bear mainly includes the net weight of the soil layer covered, the working pressure that is likely to be formed by the pavement building, the load of the past vehicles on the road, and so on. Since the PE pipe is a flexible pipe, the load from the outside will be dispersed into the nearby soil layer due to the deformation of the pipe. The larger the diameter of the pipe, the lower the ring stiffness is. When the weather temperature decreases, the strength of the PE pipe will be increased, and the ring stiffness will also increase.
At this stage, the numerical index value of ring stiffness is widely used in the overpressure load working capacity of PE water supply pipes. If the ring stiffness of the PE water supply pipe is too small, the pipe is likely to be excessively deformed, unstable or ineffective. Conversely, if the ring stiffness is selected too high, it is likely to cause high cost due to the application of an excessively large moment of inertia of the section. Therefore, when we choose PE water supply pipes, we must contact the actual situation.