Brief introduction of glass fibre reinforced plastic pipe
Glass steel duct is a kind of non manufacturing metal composite material products, is mainly formed by resin and glass fiber and add high quality quartz sand by winding machine control, it has the properties of glass steel corrosion resistance, high strength, long service life, convenient installation and reliable, widely used in petroleum, chemical industry, environmental protection, drainage and irrigation etc..
FRP duct is a kind of light, high strength and corrosion resistant nonmetal pipe. It is based on glass fiber resin matrix according to the requirement of process layer wound on the mandrel rotation, and distance evenly between the fibers as the sand layer Kamiishi Eisa. The pipe wall structure reasonable and advanced, can give full play to the role of material, to meet the premise of use strength, improve the rigidity, ensure the stability and reliability of the product. Glass steel sand with its excellent chemical corrosion resistance, high strength and light weight, no scaling, strong shock resistance, and ordinary steel compared with long service life, low cost, quick installation, safe and reliable, accepted by the majority of users.
Fiberglass reinforced plastic pipe, function, characteristic
1. It has excellent corrosion resistance
Do not use cathodic protection and other anti-corrosion measures to produce two contamination of water and other media. Long service life of products.
2, light weight, high strength
The weight of the pipe is only 1/4 of the same size and the same length as the ductile iron pipe, and 1/10 of the cement pipe. The transportation is easy to handle and easy to install.
3 、 length of single pipe length
Reduce pipe connection, speed up installation, improve the quality of the whole pipeline.
4 、 the inner wall of the pipe is smooth
Reduce flow resistance, increase flow speed and reduce energy consumption. Compared with the same size steel pipe, the flow rate of the same volume can be increased by about 10%, and no fouling and long-term use can not reduce the flow rate. The protection of cables in interference and heavy corrosion environment is better.
FRP pipe raw materials used
FRP winding pipes are made of resin (feed water, food grade resin), glass fiber and quartz sand as raw materials and made by special process.
Glass fiber reinforced plastic pipe paste molding
1, mixing material: making slurry should be mixer mixing, artificial mixing must ensure uniform mixing, shall not be mixed with raw meal, the slurry must be side mixing side, with slurry slurry may not be used.
2, the strength of the monolithic magnesium gas pipe is determined by the combination of the inorganic cementing material and the quality and the number of plies of the glass fiber cloth. Therefore, the wall thickness of the magnesium glass tube should be controlled in a reasonable range. The wall thickness of magnesium silicate pipe and the specification of flange and the number of layers of glass fiber cloth shall conform to the provisions of table 5.2.3-1 and table 5.2.3-2.
Table 5.2.3-1 wall thickness of magnesium silicate duct and flange specification (mm)
Circular duct diameter or length of side wind D size B (mm) wind pipe thickness (mm) flange specifications (mm) width * thick flange flatness (mm)
D (b) = 3002.5 ~ 3.540 * 10 = 2
300 500 1000 1500 D (b) >2000 7.5 ~ 8.555 * 20 = 3
Table 5.2.3-2 glass fiber cloth thickness (mm) and number of plies
Circular duct diameter or length of side wind D size B (mm) tube glass fiber cloth layers of glass fiber cloth layers of flange
C1 C2 C1 C2
D (b) = 3005497
300 500 1000 1500 D (b) >2000 1492116
Note: C1 and C2 are glass fiber fabrics of thickness 0.3mm and 0.4mm, respectively.
FRP wind pipe hand paste process
1) first release agent coated on the die forming surface (or die in the outer surface of a layer of transparent glass paper), to be fully dry, plus there will be the initiator (or curing agent) and accelerant additive evenly on the mold surface, then put the cut glass cloth in the upper berth. Then apply the magnesium oxychloride cement on the paved glass cloth and take care to remove the bubbles. A good coating of magnesium oxychloride cement paste then with cut glass cloth, so the operation is repeated, until it reaches the design and specification of thickness.
2) the wind pipe surface thickness of the slurry to flatten the glass fiber mesh cloth texture is appropriate (see:). No dense air holes and grout leaks are allowed on the wall of the pipe to avoid the stress concentration under the bending tensile stress (positive air pressure) and the bending compressive stress (negative wind pressure).
3) there is a transition arc between the pipe body and the flange corner, and the transition arc radius should be 0.8 to 1.2 times the wall thickness, so as to improve the carrying capacity of flange and avoid stress concentration in the cantilever state. Fiberglass mesh shall be extended to the duct at the flange of the duct.
4) glass fiber mesh length and width must take the overlapping method is not enough, in order to improve joint tangential bearing capacity, so as to effectively overcome the radial tensile stress, bending stress and bending shear stress. The lap length of the glass fiber cloth at the joint is generally 50 to 100mm, and the joint of each glass fiber cloth should be at a certain distance from the adjacent joint. The longitudinal and transverse joints between adjacent layers shall be greater than 300mm, and the distance from the same seam shall not be less than 500mm.
5) paste made of circular duct, glass cloth along the radial 45 degree angle to the direction of cut cloth; conical paste products, according to the fan-shaped cloth.
6) when the length of the rectangular duct is greater than 900mm and the length of the pipe is greater than 1250mm, the reinforcement of the duct shall be strengthened. Reinforcement shall be made of bulk material (fiber reinforced polymer) and strengthened at maximum stress