The full name of FRP is glass fiber winding reinforced thermosetting resin sand pressure pipe, also known as sand pipe.It is generally composed of glass fiber reinforced plastic structure layer, quartz sand layer and inner lining layer.This structure of glass fiber reinforced plastic pipe makes it have corrosion resistance and high mechanical strength. , Low resistance to fluids, light weight, long life and ability to keep water quality clean and hygienic.
An important influence in engineering design is its excellent mechanical and physical properties. The density of FRP is 1.9-103kg/m3, which is about 1/4 of the steel pipe; the circumferential tensile strength is about 300Mpa; the axial tensile strength About 160Mpa; it can be seen that its strength is much higher than steel, cast iron, plastic and other materials. Another important feature of FRP is the low resistance of the smooth inner wall to the fluid: due to its smooth inner surface, it is not easy to produce corrosion tumors and corrosion effects, the friction resistance is small, and the head loss is significantly smaller than other pipes, which is reflected in the typical Manning (Manning) The long-term flow coefficient value n is 0.009 and the Hasson` Williams coefficient C is 150 (taken from JC/T838?? 1998 glass fiber winding reinforced thermosetting resin sand pressure tube). This means that the use of glass fiber reinforced plastic resin pipes for water delivery has a small head loss, which can improve the water delivery capacity and save operating costs. Compared with other pipes, a smaller pipe diameter can be used, thereby reducing the one-time investment of the project. But this does not mean that the prestressed reinforced concrete pipe has no merit in the project. The determination of the pipe material is the result of an economic and technical comprehensive comparison