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【PE】 February 24 Shanghai Petrochemical PE pipe material prices
China shuo po network core tips: First, using buried polyethylene gas pipeline system development history of this century occurred in the area in the pipeline a revolutionary progress, namely, "plastic on behalf of the steel." With the leap in polymer materials science and technology progress,
1, gas using buried polyethylene pipe systems development history of this century occurred in the area in the pipeline a revolutionary progress, namely, "plastic on behalf of the steel." With the leap in polymer materials science and technology progress, development and utilization of plastic pipe deepening of the continuous improvement of production process, plastic pipe vividly demonstrate the superior performance. Today, plastic pipe is no longer mistaken for a metal pipe that people "low-cost substitutes." In this revolution, polyethylene pipe, the acclaimed, eye-catching ever issued by the brilliant, widely used in gas transmission, water supply, sewage, agriculture, irrigation, mines fine particles of solid conveying,
As well as oil, chemicals, and postal and telecommunications services in areas such as extraordinary in the gas transport has been generally on the application. 1. Foreign polyethylene gas pipe development history in 1933 found the company was the first British ICI polyethylene. Development to date, polyethylene is produced by a variety of process methods, with a variety of structures and properties and a series of varieties of multi-purpose resin, synthetic resin production accounts for one third of the world, ranking first. World War II, due to the shortage of copper and steel, began to study abroad in areas such as the use of plastic gas distribution pipes. Gas transmission and distribution of materials to use plastic pipe applications, start by age are as follows:
acetic acid - acid fiber Su, hard PVC, impact-resistant polyvinyl chloride, epoxy glass fiber reinforced plastic, polyethylene, polyester and nylon. With the passage of time and gas engineering experience in running constantly sum up, people become familiar with the plastic tube should be considered in the application of the following factors:
a. economy b. interface, stability, and rigor c. Environmental Stress Cracking Resistance d. corrosion resistance and chemical resistance e. aging f. toughness g. soft, flexible h. intensity and temperature durability i. j. a long-term hydrostatic strength of the relationship between the size of the order of elimination through to the late 60s, leaving only PVC pipe and polyethylene pipe. Although the strength of PVC pipe, low cost, but has the following disadvantages when compared with polyethylene: a. brittle, easy to produce fracture phenomena; b. lack of flexibility can not be coiled, etc.; c. the reliability of solvent exposure and poor .
Therefore, using a substantial reduction in the number of PVC pipe, while the significant increase in the use of polyethylene pipes. Since 1956, the laying of the first polyethylene gas pipelines since the 70's, in Europe and North America, polyethylene pipe, gas fields in the rapid popularization and application. Polyethylene pipes in various countries on the wider use of gas pipelines has become a pipeline of the most remarkable achievements in the field. This is because polyethylene pipe material has a very unique technical and economic advantages, and partly because the raw material properties of polyethylene pipe, pipe, pipe fittings manufacturing process, the connection method, connection equipment, and maintenance of the operation means the many years of practice, has reached the perfect auxiliary systems. Today, in the gas collar
Domain, whether it is for new installation or repair and update the old pipes and polyethylene pipes are the main options. PE gas pipe penetration in Europe is extremely high, such as the United Kingdom, Denmark and other countries more than 90%, France's newly installed gas pipeline in 1998 is almost 100% use of polyethylene pipe. As early as in 1988, held in Munich in conjunction with the International Coal Gas Committee meeting, members agreed that the use of polyethylene for Buried Gas Pipeline reliable quality, safety, maintenance is simple, cost the economy. This consensus is clearly five decades of polyethylene pipe and other pipes repeated comparisons, competition reached. It should be noted that not only should be attributed to the excellent PE pipe
Overall performance, but due to performance of PE pipe materials, pipe, pipe fittings manufacturing process, the connection method, connection equipment, and maintenance of the operation means in practice for many years and continued to make revolutionary progress. In case of PE pipes, one of the most important factor affecting the performance of raw materials, with the polymerization process improvement and eighties the level of PE pipe raw material compared with the level of the seventies, that made tremendous progress. After nearly half a century of continuous development, to date, polyethylene pipe has become the most mature one of the varieties of plastic pipe.
Since the early sixties, and explore polyethylene pipe for gas transportation has been around the various aspects of polyethylene piping systems for research and development work have been without interruption, and very active. Many countries in the world polyethylene resin manufacturers, pipe manufacturers, pipe fittings and pipe accessories manufacturers, pipe extrusion equipment manufacturers, pipeline construction and the use of units, construction equipment manufacturers, product certification bodies, the universities and scientific research institutions are a great enthusiasm to put into this work. Research and development of the breadth, depth and speed, is difficult for other types of plastic piping with the match. Polyethylene pipe systems outstanding performance of the high level of maturity in:
The continuous development of polyethylene pipe grade raw materials, the late eighties the third generation of polyethylene pipe resins have enabled the use of large diameter pipe also has an advantage. Rigorous and scientific pipeline design. Long-term use of polyethylene pipe materials, the formation of a systematic evaluation of the performance standards of scientific evaluation method, which is designed to ensure the long-term use of the performance and the use of security. A highly sophisticated manufacturing equipment and extrusion process. Synchronous development with the pipe, multi-species matching fittings. Pipe connections, construction and maintenance of mature technology and equipment. A wealth of research results, a large number of successful engineering practice and systems complete standard system.
From raw materials to construction, from the product requirements to quality control methods, polyethylene piping systems with a comprehensive ISO standard. The high level of standard and systematic, marks a highly sophisticated development of polyethylene pipe. 2. Domestic polyethylene gas pipe development history of China from the early 80s the research work of polyethylene gas pipe, the earliest use of polyethylene pipes conveying town gas in 1982 in Shanghai. In order to study PE gas pipe be taken seriously and carried out smoothly, the State Science and Technology Commission in 1987 of "PE Gas Pipe Compound for application development and process technology development" as a state "7
5 "science and technology research project, from the special raw material ─ pipe, pipe fittings processing ─ ─ engineering application of standards and norms developed to conduct systematic research and achieved fruitful results. In 1995, Bureau of Technical Supervision, the Ministry of Construction were awarded the PE gas pipe, pipe fittings National Institute of Standards and engineering industry procedures. At present, PE gas pipe is promoting the use of domestic fast. In PE gas pipe under the impetus of domestic basically grasp the PE Pipeline production and use of technology, the introduction of a considerable number of world-class production line, the formation of a considerable scale production capacity. This is the development of polyethylene gas pipe laying a solid A strong foundation. 99 years of domestic production of polyethylene gas pipe nearly 10,000 tons, and 20% annual growth rate of forward. 2, polyethylene gas pipe materials properties and their development in accordance with customary density polyethylene pipe is divided into low-density and linear low density polyethylene pipe, medium-density polyethylene pipe and high-density polyethylene pipe. As the material advances, according to the different stages of development and performance, resulting in the level of differentiation of the material, density polyethylene as the pipe does not reflect the nature of performance, so the current international on the basis of polyethylene pipes for the long-term hydrostatic strength of pipe and raw material be classified and named. The long-term hydrostatic strength of
Refers to the continuous imposition of polyethylene resin in the tube wall when the 50 years when calculating damage caused by pipes in the wall of the circumferential tensile stress, the value is the basis for structural design of pipe. The concept of the engineering design of polyethylene pipe and metal pipe is different from the metal tube design, extensive use of ambient temperature yield strength coefficient. The polyethylene pipe and metal pipe is different from it is subject to continuous stress and temperature change, so the design of polyethylene pipe stress should be based on long-term strength to decide, that is, under constant temperature by drawing the curve of time, stress and damage to determine. According to the long-term polyethylene pipe hydrostatic strength, the international polyethylene pipe materials will be divided into PE32, PE40, P E63, PE80 and PE100 five grades. At present the international use of the largest pipe resin MRS value of 8.0MPa, and the MRS value of 10MPa pipe resin has been successfully developed, this resin using bimodal distribution, hexene copolymerization technology, in improving the long-term hydrostatic strength at the same time , but also increased resistance to slow crack growth and resistance to rapid crack extension performance, and has a good processability, in order to improve the pressure transmission pipeline network, increasing the pipe diameter to expand the scope of application to create the conditions for the pipeline. The current use of PE100 pipe, extraordinary in the large-diameter pipe on the dosage, is growing rapidly. Table 1 lists the current European PE100-level pressure on the actual use of polyethylene gas pipe. |
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