Glass fiber reinforced plastic sand pipe mainly resin, chopped fiber, continuous glass fiber reinforced plastic, quartz sand and other components, mainly for buried pipes and long-distance pipeline, with a light wall, corrosion resistance, long life, low operating and maintenance costs And other characteristics, can save a lot of money for the construction project.
performance
(1) light high strength: for the same diameter of the unit length of weight, RPM tube only carbon steel 1/3, cast iron pipe 1/5, pre-stressed tube 1/10, in the construction to reduce the lifting costs, The installation speed.
(2) has good resistance to water corrosion, no cathodic corrosion protection and other anti-corrosion measures, will not produce secondary pollution to water or other media. Reducing the cost of anti-corrosion, extending the service life.
(3) hydraulic characteristics of good, this feature is particularly prominent in the field of drainage, such as saving pipe network pumping costs, for the same diameter pipe network, glass fiber reinforced plastic pumping costs 30-40%; reduce pipe size, The same flow, the use of glass fiber reinforced plastic sand pipe, pipe diameter can be reduced by 10-25%, thus saving investment costs; shorten the pumping time, especially for centralized water or gap with water, saving 1/3 pumping time and cost. Glass fiber reinforced plastic sand pipe wall is smooth, not only the new ecology is smooth, and the use of quite a year later, the inner wall is still smooth as ever, and not scaling. In foreign countries is called "hydraulic smooth tube".
(4) pressure: according to the pressure required by the process, design, manufacture pipes and pipe fittings to the required 1.5 times the pressure required for water pressure test.
(5) the use of corrosion-resistant quick connector, connector with a double "O" type rubber seal socket connection. Easy to install, sealed, corrosion-resistant, joints in the range of 3 ° can adjust the direction of any pipeline. Interface sealing is good, do not leak, will not break, increase water supply safety and reliability.
Manufacture, design and construction of sand glass fiber reinforced plastic (FRP)
The material industry is the foundation of all industries. The new material industry is the indispensable material industry for the development of modern science and technology. With the development of modern technology, a single material performance has been unable to meet the needs of production and social development. The use of composite technology will be different characteristics of the material together, made with excellent overall performance of the composite material came into being. It can be given by the user needs to be a single component of the material does not have the characteristics, such as light, high strength, insulation, corrosion resistance, temperature, heat insulation and other excellent performance, and even meet the requirements of users in special conditions, Can achieve energy saving, reduce costs, improve working conditions, waste recycling and other comprehensive purposes, greatly improve the economic efficiency of enterprises.
1.1 The trend of the development of materials industry - the rise of non-metallic composite pipe
The development of composite materials has contributed to the great revolution in the material industry. The birth of glass pipe (referred to as GRP pipe), marking the non-metallic pipe in the material industry in the rise, but also indicates that non-metallic pipe construction in the national economy in the application areas and the market will continue to expand and become more broad. Glass fiber reinforced plastic pipe is a new type of composite pipe, which is mainly made of glass fiber yarn as a reinforcing material and resin as a matrix, with many other pipe can not replace the superior performance, is widely used in chemical enterprises corrosive media transportation, Oil and gas transportation, agricultural irrigation, seawater transportation, power plant circulating water, and urban water supply and drainage engineering and many other areas. With the popularity of glass fiber reinforced plastic applications, there have been sandpaper glass pipe (referred to as FRP), this pipe not only from the performance to improve the pipe stiffness, and reduce the cost of the pipeline. Therefore, in recent years in the city of water supply and drainage works particularly favored. The following we focus on the application of sandpaper glass pipe to elaborate.
1.2 Glass fiber reinforced plastic pipe in the international market and domestic manufacturing and application profiles
Composite materials industry, the glass industry in the current international market, the largest output, the most widely used. Since the mid-80s, in some European countries, the new large and medium-sized water supply pipeline, the use of glass pipe length ratio of 10% -50%. British glass pipe accounts for more than 25% of the total water supply, in the expected period of time will increase to 30% -50%. Swedish glass fiber reinforced plastic pipe length ratio of 40%, more than 300mm in diameter of the new laying of municipal pipelines in 80% of glass pipe. Japan in large-caliber urban water supply pipeline, glass pipe accounted for 25%, more than the amount of steel pipe. In the Middle East, large and medium-sized water pipes, sewage pipes, desalination system pipelines and some industrial pipelines, are used glass pipe. Since the United States since 1986, the annual output of glass fiber reinforced plastic more than 60,000 tons, the installation of the total length of glass fiber reinforced plastic pipe 1 million km, the future development of the US glass pipe is expected to grow by an average of 10%.
China's FRP industry in recent years has developed rapidly, in 1992 the National Building Materials Bureau to the development of production in 2000 to 300,000 tons / year scale, FRP development and application has attracted more attention. Since the 1980s, China has introduced four winding tubes and two centrifuge tube production lines from Italy, Japan and France, and the annual production capacity has been greatly improved. However, due to the current development and application of sandpaper glass pipe has not been widely promoted, resulting in many applications of its performance, quality and application areas are not fully understood. In addition, many enterprises have not yet reached the production capacity of saturation, so sandpaper glass pipe in the national economy in the application market has yet to be opened up. In the current rapid development of China's economy, the market economy gradually improve the excellent situation, the new composite pipe - sandpaper glass pipe in the field of urban water supply will be its high-quality performance to replace other pipe, which is the inevitable trend of the development of composite materials industry. In China, the use of sandpaper glass pipe is also gradually attracted people's attention, long-distance water delivery projects are more and more, the market prospects are bright. According to the Ministry of Construction predicted that in our country during the "Ninth Five-Year Plan" period of China's annual need to lay the pipeline about 1,600 km, which shows that the potential market of sandwich glass pipe is a broad prospect.
1.3 characteristics of sandpaper and its adaptability with the times
Sandpaper glass pipe with its excellent corrosion resistance, light high strength, transport flow, easy installation, short duration and low comprehensive investment advantages, as the chemical industry and water transport project the best choice. It has other metal pipe can not be compared to the superiority, mainly has the following characteristics:
1. Has excellent corrosion resistance.
Compared with the traditional pipe has excellent resistance to chemical corrosion, can be acid, alkali, salt, oxidants, organic solvents, all kinds of oil, sewage, sea water. Its lining with excellent corrosion resistance of the resin (drinking water pipe using food grade resin) as a raw material, so do not need any anti-corrosion treatment.
2. No toxic, no secondary pollution.
In the course of the use of non-scaling, no rust, do not breed algae and other microorganisms, do not need cathodic protection and other protective measures, will not produce secondary pollution to water quality or other media.
3. Small proportion, light weight
The proportion of steel, cast iron pipe 1 / 4-1 / 5, concrete 2/3. Pipeline weighs about the same size, with the length of ductile iron pipe 1/4, concrete pipe 1/10. Therefore, easy loading and unloading, easy to install.
4. Single pipe length is long.
The length of the pipeline is generally: 6m, 8m, 10m, 12m, 16m (can also be produced according to customer requirements of the special length of the pipeline). Single pipe length, the number of interfaces is small, thus speeding up the installation speed, reduce the probability of failure, improve the quality of the entire pipeline installation.
5 mechanical good, excellent insulation performance.
Pipeline tensile strength lower than the steel, higher than the ductile iron pipe and concrete pipe, and the strength is about 3 times the steel pipe, ductile iron pipe 10 times, 25 times the concrete pipe. In addition, its thermal conductivity is only 1% of the steel pipe, with excellent insulation, to adapt to the use of transmission, telecommunications line-intensive areas and mine areas. The performance comparison is shown in Table 1.
Table 1 the performance of the various materials of the pipeline
performance
RPMP
Steel Pipe
Cast iron pipe
Concrete pipe
Ring tensile strength (Mpa)
360
480
150
2.1
Axial tensile strength (Mpa)
55
480
135
2.1
Specific strength (Mpa)
200
61.5
20.8
0.8
Thermal conductivity (kcal / m · h · ° C)
0.25
27.2
15.0
2.1
6. Excellent hydraulics performance, saving energy.
The sandwich glass pipe has a smooth inner surface, suitable for large diameter (≥ φ500mm) water pipeline characteristics, grinding coefficient is small, hydraulic fluid characteristics, and the greater the diameter of the more obvious advantages. It is this feature that the same diameter of the pipe flow, RPMP maximum. On the contrary, in the case of pipeline traffic flow the same, the project can be used smaller diameter sandwich glass pipe instead, thereby reducing the one-time project investment. Filled glass fiber reinforced plastic pipe in the process of conveying water compared with other pipe, can greatly reduce the loss of pressure, saving pump power and energy.
7. Thermal expansion coefficient is small.
As the RPMP thermal expansion coefficient is small, in the use of no need to add temperature compensation measures, in the surface, underground, overhead, submarine, alpine, desert, frozen, wet, acid and other adverse conditions under normal conditions.
8. Long life, safe and reliable.
The sandwich glass pipe is designed to be durable and the safety factor is generally above 4. According to the laboratory simulation test table: the general water supply, drainage sandpaper glass pipe life of up to 50 years, is the steel pipe and concrete pipe 2 times. For corrosive media, its service life is several times higher than that of steel pipes and stainless steel tubes.
9. Flexible design, product adaptability
Sandwich glass fiber reinforced plastic pipe can be based on the user's various special requirements, by changing the design, to create a variety of specifications, pressure level, stiffness level or other special performance products for a wide range.
10. Use corrosion-resistant quick connector.
Joints generally use two connections: two "O" -shaped ring and the reaction of elastic seal ring (Figure 1). Easy to install, reliable, sealed, good corrosion resistance, joints can be in a small angle within the scope of arbitrary adjustment of the direction of the pipeline.
11. Comprehensive low cost, long-term economic benefits.
For the same diameter of the pipe, RPMP single pipe prices slightly higher than the concrete pipe, and lower than the cast iron pipe and steel pipe. The larger the pipe diameter, the greater the difference in pipe cost. Therefore, taking into account the long-term use of pipeline maintenance costs and power consumption and other operating costs, as well as the useful life and delivery capacity and other factors, RPMP comprehensive benefits are better than other pipe.
It is precisely because the sandwich glass pipe has a series of advantages, will gradually replace the traditional steel pipe, cast iron pipe and other pipe, with the era of adaptability. This kind of adaptability is mainly manifested in the following aspects: First, the novelty of the product is reflected in the advanced technology, structural selection is more reasonable; Second, the economy of the product [more reflected in the unique sandwich glass pipe outstanding Performance, and product prices are gradually reduced; third, the product is more practical. It can be applied to a variety of soil conditions, even in high acid, high alkali soil does not require chemical protection, greatly improving the service life of the pipe. In short, sandpaper glass pipe will be with China's economic development, will be promoted and applied.
