There are two types of FRP pipe forming methods, one is a fixed length pipe and the other is a continuous pipe. FRP pipe has a series of excellent characteristics such as anti-corrosion, anti-fouling, anti-smacking, heat-resisting, antifreeze, and good designability. It is widely used in the water supply and drainage industry. Similar to container forming, except that the pipe does not require a head. Generally, the winding angle greater than 54.7 degrees is used to return at the tube end with a winding distance of approximately 90 degrees, and the fibers at the tube end are stacked more, and the circumferential strength and rigidity of the joint are utilized to ensure the sealing performance. Large-diameter long-distance transmission pipelines are connected by O-ring sockets, and both ends of a single pipeline are made into a negative and a positive form. Most of the short distance above-ground process pipelines use glued connections. Process piping requires a large number of fittings, such as three links, elbows, and so on. High-performance pipe systems and pipe fittings use continuous filament winding, and the winding of pipe fittings is much more complicated than straight pipes and containers. Although multi-shaft and even manipulator pipe winding units have been developed at present, they cannot be promoted in industrial pipe fittings due to economic reasons. Manufacturing. Therefore, the coiled pipe fittings are mostly semi-manually completed. In buried large-diameter pipelines, in order to reduce costs and increase the rigidity of resistance to external pressure, sand-filled pipelines have been developed to reduce pipeline costs by approximately 50%.

Compared with other materials, FRP pipe has the following significant advantages:

1. Corrosion-resistant pollution-free fiberglass pipe can resist acid, alkali, salt, seawater, untreated sewage, corrosive soil or groundwater and many chemical fluids. The glass fiber reinforced plastic pipe has the excellent characteristics of being non-toxic, rust-free, tasteless, no secondary pollution to the water quality, and no need of anti-corrosion. Therefore, it is widely used in the water supply and drainage industry.

2. Anti-fouling and anti-corrosion pipelines use unsaturated polyester resin on the surface, so the surface is clean and smooth, and it will not be contaminated by microorganisms such as shellfish and fungi in the ocean or sewage, resulting in increased roughness and reduced over-water. Sections, increase maintenance costs. The pipeline is free of these pollutions and is used as clean and clean as before.

3. Heat-resistant and anti-freeze still has good toughness and high strength at -30°C. It can be used in the range of -50°C-80°C for a long period of time. It can also be used above 110°C with special formula resin. Temperature work.

4. Light weight, high strength, convenient transportation, and easy installation. Fiberglass pipe produced by filament winding process has a specific gravity of 1.65-2.0, only 1/4 of that of steel, but its circumferential tensile strength is 180-300 MPa. Tensile strength is 60-150MPa, similar to alloy steel. Therefore, its specific strength (strength/specific gravity) is 2-3 times that of the alloy steel, so that it can be designed according to the different requirements of the user to meet various types of pipes that can withstand internal and external pressure requirements. For the same pipe diameter single glass pipe only 1/2.5 of carbon steel pipe (steel coil pipe), 1/3.5 of cast iron pipe, about 1/8 of prestressed reinforced concrete pipe, so it is very convenient for transportation and installation. The length of pipe is 12 meters in each section, which can reduce two-thirds of joints compared with concrete pipes. Its socket connection method is quick and easy to install, and at the same time it reduces the lifting costs and greatly increases the installation speed.

5. Small frictional resistance High conveying capacity The inner wall of the glass pipe is very smooth, and the roughness and frictional resistance are very small. The coefficient of roughness is 0.0084, while the concrete pipe has an n value of 0.014 and a cast iron pipe of 0.013. Therefore, the glass pipe can significantly reduce the fluid pressure loss along the way and increase the transport capacity. Therefore, it can bring significant economic benefits: When the transportation capacity is the same, the project can choose a glass fiber pipe with a smaller inner diameter, thereby reducing the one-time investment; using the same diameter pipe, FRP pipe can reduce the head loss than other materials Saves pumping costs. In addition, FRP pipes can reduce pumping time and reduce long-term operating costs.

6. Good electric insulation The glass fiber reinforced plastic is non-conductor. The electric insulation of the pipe is excellent. The insulation resistance is in the range of 1012-1015Ω.cm. It is most suitable for use in transmission. The heat transfer coefficient of the glass fiber reinforced plastic area and the multi-destination area is very small. 0.23, which is 5/1000th of steel, has excellent thermal insulation properties.

7. Good wear resistance Contain a lot of mud, sand and water, into the tube for comparative test of rotating wear. After 3 million rotations, the depth of wear on the inner wall of the test tube is as follows: 0.53 mm for tar and enamel-coated steel tubes, 0.52 mm for steel tubes coated with epoxy resin and tar, and surface-hardened steel tubes. It is 0.21mm. This makes FRP wear resistant.

8. Maintenance cost Low glass steel pipe Due to the above-mentioned properties of corrosion resistance, wear resistance, frost resistance and anti-fouling, the project does not require measures such as rust prevention, anti-fouling, insulation, and heat preservation. There is no need for cathodic protection of buried pipes, which can save engineering maintenance costs by more than 70%.

9. Good design The glass steel pipe can be designed and manufactured into pipes of different pressure grades and stiffness grades according to various specific requirements of users, such as different flow rates, different pressures, different buried depths and load conditions.

10. Longevity and Comprehensive Benefits According to lab simulation tests, the service life of FRP pipes can be as long as more than 50 years. The comprehensive benefit refers to the long-term result of various factors such as construction investment, installation and maintenance costs, service life, and energy-saving steel. The comprehensive benefits of the FRP pipe are desirable. In particular, the larger the pipe diameter, the lower the cost. When further consideration is given to the long service life of pipelines buried underground, and without the need for annual overhauls, the overall efficiency is good.