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发布日期:2021年01月24日
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TITLE: PPR feed pipe
Specification:
Scope of application:
Detailed

 

Pp-r pipe

Pp-r (polypropylene random) call also called three type polypropylene pipe and random copolymerization polypropylene pipe or PPR pipe, energy saving material saving, environmental protection, light weight, high strength, corrosion resistance, smooth inner wall does not scale, construction and maintenance is simple, long life and other advantages, is widely used in building water supply and drainage, urban and rural water supply and drainage, city gas, electricity and cable sheath, industrial fluid transportation, agricultural irrigation, construction, municipal, industrial and agricultural areas. PP - R tube is made into pipe by extruding polypropylene, which is extruded into pipe.

Summary of pp-r pipe

PPR pipe with the traditional cast iron pipe, galvanized steel pipe, cement pipe and other pipe, compared with energy saving material, environmental protection, light weight, high strength, corrosion resistance, smooth inner wall does not scale, construction and maintenance is simple, long life and other advantages, is widely used in building water supply and drainage, urban and rural water supply and drainage, city gas, electricity and cable sheath, industrial fluid transportation, agricultural irrigation, construction, municipal, industrial and agricultural areas.

In recent years, along with the construction, municipal engineering, hydraulic engineering, agricultural and industrial sectors such as increasing market demand, PPR pipe industry in China presents a rapid development momentum. According to the survey, the volume of plastic pipe production in 2009 was 584,000 tons, up 18.9% year on year, and the plastic pipe production in January to September 2010 was 5528,000 tons, up 28.23% year on year. At the same time, as consumers of product environmental protection, health, durable quality requirement enhances unceasingly, along with the increase of the plastic pipe in our country in the production, product quality level enhances unceasingly, the technical progress of industry continues to increase, the brand enterprise scale increasing, new material, new structure constantly emerging varieties, advanced system design LiNianCeng out one after another, the functionality of the product more clearly, further broaden the application area. The analysis suggests that the market share of China's plastic pipe market is more than 30% in all pipelines.

To 2015, in the building, rebuilding and expansion projects, construction of drainage pipe with 85% plastic pipe, building rainwater drain 80% using plastic pipe, plastic pipe usage of urban drainage pipe reached 50%, 85% of building water supply, hot water supply and heating pipe with plastic pipe, urban water supply pipe (below DN400mm) 80% by plastic pipe, rural water supply pipeline by plastic pipe, 90% (low pressure pipe) in the city gas plastic tubing are reached 40%, building wire thread casing 90% using plastic tube. It is predicted that during the twelfth five-year plastic pipe production in our country will keep growth of around 10%, to 2015, the national plastic pipe production is expected to close to 12 million tons, the plastic pipe market share of more than 60% in all kinds of pipeline in the country.

The PPR tube is officially called the copolymerization polypropylene tube, which is one of the most used water pipes in the home construction project. PPR pipe raw material quality control, PPR is made (PP and PE) gas phase synthesis of random copolymerization polypropylene, its structure is characterized by PE molecular ruleless links among PP molecules, molecular weight ranged from 300000 ~ 800000. Using PPR raw materials, it is a plastic pipe that was developed in the late 1980s and early 1990s. With its excellent performance and wide range of applications, it has gained a foothold in the plastic pipe market and is recognized as a green product. But in recent years, market operation, the PPR plastic pipes quality problem analysis, for example, it turned out that PPR pipe market, a lot of problems to a large extent these problems restricted the healthy development of PPR pipes.

PPR connection technology:

It doesn't leak, it's very reliable. But this is not to say that PPR pipe is no defect of the pipe, high temperature resistance, pressure resistance is a bit poor, long-term working temperature should not exceed 70 ℃; Each length is limited, and can not bend the construction, if the pipe is laid long or on the corner, a large number of joints will be used in the construction. The pipes are cheap but the price of accessories is relatively high. In terms of overall performance, PPR tube is the most cost-effective pipe material, so it is the first choice material for house water pipe renovation.

PPR tube color:

There are several colors in the PPR tube that are sold on the market. Why do you make this distinction between white, gray, green and curry

Pp-r pipethe color mother is different. General advice to buy white PPR pipe, because a small number of unscrupulous manufacturers will use recycled material production PPR pipe, by adding color masterbatch to cover defects caused by raw material is not pure.

PPR installation recommendation:

Generally in the water and electricity transformation, the original pipes will be replaced, and businesses of domestic outfit company is decorated in the recommended when installing the PPR pipe all use hot water pipe, even is the place that flows through the cold water with hot water pipe. They say that the water pipes are more expensive than the cold ones, and the price is not so different.

Diameter of the PPR pipe diameter (according to outer diameter) from 20 mm to 160 mm, mainly used in the home installs 20 mm (PPR is 4 in charge, and galvanized pipe have distinction), 25 mm (PPR is 6 in charge, and galvanized pipe have distinction) two kinds, including 20 mm used more. If the economy is allowed, we suggest using the PPR pipe diameter is 25 mm, especially the cold water inlet pipe, because modern highly centralized family lives, water is more and more, at the same time, the probability of water is very high, this will minimize, small flow of water down.

Pp-r pipe MPa

MPa is the pressure unit

For example:

PPR tube 25 * 2.3 1.25 Mpa means: PPR tube outside 25mm, pipe wall thick 2.3 mm, belong to S5 series pipe material, under normal temperature under pressure 12.5kg. 老头鸡儿硬微博,免费学生v片在线观看

The development of the PP - R tube

The PP - R tube is called the three-type polypropylene tube, which is extruded and made into pipe by the use of the random polypropylene. It was a new type of plastic piping product developed in Europe in the early 1990s. The pp-r, which was adopted in the late 1980s, was adopted by the gas phase copolymerization process to make about 5 percent of PE in the PP's molecular chain randomly polymerized (without the rules) and became a new generation of pipeline materials. It has good impact performance and long-term creep performance.

Pp-r pipe difference

In the previous period, PP - C pipes and fittings were found in the domestic market, and the installation method was consistent with PP - R. Many people don't know what the difference between PP and PP is, and there is a lot of misunderstanding and confusion. In international standards, PP - H, PP -b, PP - R three, no PP - C. The difference between these three kinds of PP is that the stiffness of PP, PP, PP and PP is decreasing in turn and the intensity of impact increases in turn.

In three kinds of PP pipes, tube resistance impact performance PP - R> PP - B> PP - H, tube heat deformation temperature. PP - B> PP - R, tube rigid PP - H> PP - B> PP - R, high temperature of the pipe. PP - B and PP - R. PP - B and PP - R. Relative to other PP pipe, pp-r pipe prominent advantage is not only improved the low temperature brittleness of PP - H, and at high temperature (60 ℃) has a good ability of resistance to water pressure for a long time, especially when used for hot water pipe, long-term strength than PP - H and PP - B.

The PP - C tube in the market is actually the PP - B tube, which is made from the special materials for the polymer polypropylene. The PP - B tube is a kind of cold hot water pipe, which is cheaper, and the difference between the heat-resistant, pressure-resistant performance and the PP -r is very large. For example, using condition grading 2, design pressure 0.6 MPa DN25mm tube, PP - R tube wall thick 3.5 mm, PP -b (PP - C) pipe wall is 5.1 mm thick. Design pressure 0.8 MPa DN25mm, PP - R tube wall thick 4.2 mm, and PP -b (PP -c) cannot be used. Because the wall is too thick. Market structure size PP - C consistent with PP - R tube and its conditions of use is much lower, cannot be used with pp-r pipe, more cannot be used in determining the conditions, after PP - C tube instead of pp-r pipe. Conditions of use 2 said design temperature 70 ℃, heating water.

PP - R tube processing temperature

Due to the crystallization of polypropylene is a typical polymers, the melt viscosity is very sensitive to temperature, so the processing temperature control in pp-r pipe extrusion forming process is very important. Mold temperature control in commonly 210 ~ 260 ℃, extrusion temperature is exorbitant, can lead to a word of mould material accumulation, leading to degradation of raw materials, make the pipe products performance degradation. [1]

Pp-r pipe characteristics

In addition to the characteristics of light, corrosion, non-scale and long life, the PP has the following characteristics:

1、Non-toxic and hygienic. Pp-r raw material molecules only carbon, hydrogen, there is no harmful toxic elements, reliable health, not only for hot and cold water pipes, can also be used in pure water system.

2、Heat preservation and heat insulation. The PP's thermal conductivity is 0.21 w/mk, which is only 1/200 of the pipe.

3、Good heat resistance. Pp-r pipe vicat softening point 131.5 ℃. The highest working temperature is 95 ℃, can meet the use requirements of the building water supply and drainage in the specification of hot water systems.

4、Long service life. Pp-r pipe in working temperature 70 ℃, under the condition of working pressure (P.N) 1.0 MPa, the service life can reach more than 50 years (if the pipes must be S3.2 S2.5 series and above); Room temperature (20 ℃) service life can reach more than 100.

5、Convenient installation and reliable connection. Pp-r has good welding performance, pipes, pipe fittings can be used hot melt and fused connection, convenient installation, reliable joint, the connection parts of the strength is greater than the strength of the pipe itself.

6、Material can be recycled. The pp-r waste is cleaned, broken and recycled into pipe and pipe production. The amount of recycled materials should not exceed 10%, not affecting the quality of the product.

PP - R operation instructions

PPR installation tools, including thermal melt tools and cutting tools, such as pressure regulator, electric fuse, heating device, cutting machine, and complete set of integrated tools. Heating power choice of fusion tool: usually 700-800 w is less than 63mm diameter pipe; 1200-1500 W for pipe outer diameter is greater than 75mm.

PP - R main advantage

1、The quality of light

20 ℃ when the density is 0.90 g/cm3, weight is only one 9 of the steel tube, one over ten of the copper tube, light weight, reduce construction intensity greatly.

2、Heat resistant performance is good

Instantaneous temperature is 95 ℃, use for a long time, the temperature can reach 75 ℃, is by far the most ideal indoor hot and cold water pipes.

3、Corrosion resistance of

Non-polar materials, all ions and structures in the water are chemically resistant to rust and corrosion.

4、Low thermal conductivity

With good thermal insulation, no additional insulation is required for hot water system.

5、Small pipe resistance

The smooth inner wall of the pipe makes it smaller than the metal pipe and less energy.

6、Pipe connection

With good thermal melt properties, the heat fuse links the pipe and pipe of the same material into a perfect whole, eliminating the leakage problem.

7、Health, non-toxic

In the process of production, construction and use, the environment is free of pollution and belongs to the green building materials.

 

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