The steel mesh skeleton polyethylene composite pipe has the common features of anti-corrosion, non-fouling, smooth low resistance, heat preservation, no waxing, wear resistance, light weight and the like, and its unique structure also creates the following characteristics. Skeleton composite pipe manufacturers understand together:
(1) Good creep resistance and long lasting mechanical strength
Because the plastic will creep under normal temperature and stress, brittle fracture will occur under the action of higher permanent stress, so the allowable stress and pressure bearing capacity of pure plastic pipe is very low (generally within 1.0Mpa). The mechanical strength of steel is about 10 times that of thermoplastics, and it is very stable and does not creep in the temperature range of plastics. After the mesh steel wire skeleton is combined with the plastic, the wire mesh skeleton can effectively restrain the creep of the plastic, and the permanent strength of the plastic itself is greatly improved. Therefore, the allowable stress of the steel mesh skeleton polyethylene composite pipe is doubled than that of the plastic pipe.
(2) Good temperature resistance
The strength of the plastic pipe generally decreases with increasing temperature in the temperature range of its use, and its strength is reduced by about 10% for every 10 °C increase in temperature. Since the strength of the steel mesh skeleton polyethylene composite pipe is about 2/3, which is borne by the steel mesh skeleton, its strength is lower than that of any pure plastic pipe as the use temperature is increased. The experimental results show that for every 10 °C increase, the strength of the steel mesh skeleton polyethylene composite pipe is reduced below 5%.
(3) Rigidity, good impact resistance, good dimensional stability, moderate flexibility, rigid and soft
The elastic modulus of steel is usually about 200 times that of high-density polyethylene. The rigidity, impact resistance and dimensional stability of the steel mesh skeleton polyethylene composite pipe are better than any pure due to the strengthening of the steel mesh frame. Plastic pipe. At the same time, since the mesh steel skeleton itself is a flexible structure, the composite pipe also has a certain flexibility in the axial direction. Therefore, the pipe has the characteristics of rigid and flexible combination, and is excellent in handling, transportation, installation adaptability and operational reliability. Ground installation can save the number of supports and low cost; underground installation can effectively withstand the sudden impact load caused by settlement, slippage, vehicles and so on. The small-diameter pipe can be bent properly, and the pipe fitting can be saved with the undulating arrangement or the serpentine arrangement.
(4) Small thermal expansion coefficient
Since the steel pipe has a linear expansion coefficient of 10.6 to 12.2×10-6 (1/°C), the linear expansion coefficient of the pure plastic pipe is 170×10-6 (1/°C), and the steel mesh skeleton polyethylene composite pipe is in the mesh steel. Under the constraint of the skeleton, the thermal expansion of the composite pipe is greatly improved. It is lower than any common plastic pipe. After testing, the expansion coefficient of the steel mesh skeleton polyethylene composite pipe is 35.4~35.9×10-6(1/°C), only It is 3 to 3.4 times that of ordinary carbon steel pipe. The experimental results show that the thermal compensation device can generally be used in the buried installation, and the pipe can be absorbed (or released) by using a braided laying, thereby reducing the installation cost.
(5) No rapid cracking will occur
Pure plastic pipes, especially large-diameter pure plastic pipes, are prone to rapid cracking caused by local defects and stress concentration under the action of persistent hoop stress at low temperature (currently several hundred meters to more than 1000 meters), so the current international pipe The anti-fast cracking performance of plastics places high demands, while low carbon steel does not have brittle fracture problems. The presence of steel mesh makes the deformation and stress of plastics not reach the critical point for rapid cracking. Therefore, in theory, there is no rapid cracking in the steel mesh skeleton polyethylene composite pipe.
(6) Steel and plastic materials are uniform and reliable
At present, the steel-plastic composite pipe on the market is a continuous regular interface due to the composite surface between steel and plastic. The long-term use is easy to delaminate under the action of alternating stress, resulting in leakage at the joint, bottleneck shrinkage inside, failure to block. . Compared with the steel mesh skeleton polyethylene composite pipe, the mesh structure is tightly integrated with the steel wire mesh through a special hot melt adhesive (modified HDPE). The two materials have large and uniform mutual binding force and small stress concentration.
(7) Double-sided anti-corrosion
The steel wire mesh skeleton is composited in plastic through a special hot-melt adhesive layer. The inner and outer surfaces of the pipe have the same anti-corrosion performance, wear resistance, smooth inner wall, low conveying resistance, no scaling, no waxing, obvious energy-saving effect, and are used for buried transportation and More economical and convenient under corrosive environmental conditions.
(8) Good self-tracking
Due to the existence of the wire mesh skeleton, the steel mesh skeleton polyethylene composite pipe buried in the ground can be positioned by the usual magnetic detection method to avoid damage caused by other excavation works. This damage is the most damage caused by pure plastic pipes and other non-metallic pipes.
(9) Product structure performance adjustment is convenient and flexible
The structure and performance of the product can be adjusted by changing the wire diameter, mesh spacing, plastic layer thickness, plastic and type to meet different pressure, temperature and corrosion requirements.
(10) Special electrofusion joints, various types, quick and reliable installation
The connection of the steel mesh skeleton polyethylene composite pipe adopts two methods of electric hot melt connection and flange connection. The electrothermal fusion connection is to insert the composite tube into the electric heating tube member, and heat the electric heating wire pre-buried on the inner surface of the tube member to heat it. First, the inner surface of the pipe is melted to produce a melt, the melt expands and fills the gap of the pipe pipe, and the melt is generated on the outer surface of the pipe. The two melts are fused together, and after cooling, the pipe and the pipe are tightly connected. .