】 【Weak current College of U-PVC tube in the water supply pipe application.

<br> <br> Summary: Describes U-PVC tube in the water supply pipeline application, combined with construction practice, describes the application of some U-PVC tube. <br> Keywords: water supply pipe U-PVC pipes <br> .I. introduction <br> As the city's development, the improvement of living standards on drinking water quality put forward higher requirements. At the same time, in order to guarantee the water supply network, the National Ministry of construction, chemical industry, China light .industry association, is, China Petrochemical Corporation jointly issued pipeline do not use galvanized pipe, out of grey cast iron pipe. <br> Through the analysis of water quality, integrated network, grey cast iron pipe particularly galvanized pipe is affecting water quality and network .damage one of the main causes of leakage, and as a result of grey cast iron pipe, galvanized steel pipe wall scaling enables the ability to reduce the water pipe network, increase the water resistance, a serious threat to the security and reliability of water delivery .. <br> II. application of U-PVC tube <br> Currently on the market for a wide variety of plastic pipes for water supply, various plastic pipe has advantages and disadvantages, so you must use the actual selection of suitable plastic pipes. .To do this through research and demonstration, repeatedly identified a selection of basic principles of the new tubing: <br> Complete 1, technical regulations, product standards and the design, construction and acceptance is complete; <br> 2. pipe specifications, supporting .pipe specification, the category is complete; <br> 3. ease of construction, operation, and requires no special tools, fast and reliable; <br> 4, easy to add pipes, constancy to open links next branch pipe <br> 5 ., easy maintenance, the repair method is simple, complete maintenance and fittings; <br> 6. pipe from sewage, industrial effluents and various corrosion of harmful gases, etc.; <br> Combined with the above a few basic principles, carefully on .the market, many manufacturers of products for analysis, and reference to other successful experiences and problems, according to their own practice, determine the U-PVC pipe as grey cast pipe and galvanized pipe replacement products. U-PVC tube has the weight lightly, .not rusty, non-scaling, smooth inner wall, hydraulic conditions, will not produce piping secondary pollution, but compared to other U-PVC pipe plastic tubing, mature technology, pipes, pipe fittings, specifications, ease of maintenance, etc, and have .successfully used in practice, promoting the use of U-PVC pipes. Taking into account the current production of U-PVC pipes, pipe fittings manufacturers General not very good. <br> In addition, combined with a variety of connection methods, U- .PVC construction personnel practice habits, clear DN300, DN200, DN150, DN100 tubing selection U-PVC socket rubber ring connection. <br> Third, some experience in the application of <br> U-PVC tube as buried pipes, application there are in .the country for several years, in contrast, we use later, through a period of time after use, are made in application of experience: 1, trench excavation and backfilling. <br> And ductile iron pipe and steel pipe, U-PVC tube .light weight, easy to install pipe, using fewer, on construction equipment requirements. It is based on the above characteristics, construction, construction unit to save costs, trench excavation width sometimes up to specifications, such as pipe trench width sometimes DN200 0.6-0.7 .M. Despite not affect pipeline installation, but the backfill quality difficult to ensure that the soil compaction cannot be guaranteed. Especially with the new road construction project at the same time, the General number for road units do well after the lime-stone floors, .the pipeline before excavation Groove, General piping design depth is about actual 1.5M just dug around 0.8-1M, grooves and narrow and shallow, backfill is very difficult to meet the requirement, the surface layer of pressed immediately, it is easy to cause the .pipeline rupture, also affect the quality of road works. <br> Additionally, the Groove bottom should ensure that not less than · adjustment sand layer thickness, especially in the old town, the Groove bottom construction rubbish, must strictly implement the spec, guarantee .the quality, the pipeline back to safe operation. Because of U-PVC itself pipe, pipe trench excavation should try to select the sidewalk or green belt, avoid planting in the fast lane. <br> 2, pipe installation <br> A metal .pipe U-PVC tube is important. When installed, the installation of artificial little you want lower-cost, their connection with rubber ring interface, greatly improving the efficiency of the installation, pipe diameter, the greater the more obvious superiority. Its deficiency is .the pipeline port without jacking depth marker line, not easy to grasp the depth at jacking, especially at night when you install, the greater impact, easily lead to leakage or pressure test is not successful. In addition, pipeline installation is often necessary to cut .the pipe. The cut surface must be carefully Groove, particularly over other underground facilities, because many U-PVC elbow double socket, different from the line installation. If the Groove is not in place, it is difficult to install, easy-to- .top bad rubber ring or plastic ring. For part of the pipe connections shall be glue stick, must lay, to guarantee the construction quality. <br> 3, the pipeline pressure <br> Pipe pressure test, the specification provides for hydrostatic testing of .hydrostatic pressure must not be less than the design of internal water pressure, and shall not be less than the established ductile iron pipe 0.8Mpa. test standards, test pressure regulators for 1.OMPa, 30 minutes, the U-PVC pipe axis linear expansion .coefficient than metal pipe, Division I standard specification for high pressure test, pressure test is interface usually slide out 2-5MM, so when the backfill earth pressure must meet the requirement of compactness, pipe support Pier design strength, back safe at the same time ., suppress the interface when the observation to ensure smooth pressure test, ensure that the quality of the project. <br> 4, pipe support Pier <br> As water pipes, U-PVC pipes application some time, but the related standards and specifications .are not very complete, such as pipe buttress, metal tubing buttress practices have a relatively complete standard Atlas, construction personnel on metal pipe buttress practices already familiar with the practice, the construction personnel often press metal pipe buttress practices masonry U-PVC pipes village Pier ., and U-PVC pipes and metallic pipe because of its material characteristics are very different, should distinguish between analysis, specification explicitly "U-PVC pipes shall be 360 °" full package concrete foundation treatment or enhanced pipeline carrying capacity ". To avoid stress .concentration telescopic partial damage effects tube water supply pipelines, security and reliability, combined with the relevant norms and local soil characteristics, to buttress a specification for masonry, develop construction standard, specification, construction, and ensure project quality. <br> Combined with the .experience of construction practices, to promote the implementation of the use of U-PVC pipes, based on national standards, specifications, combining the enterprise features of the design specifications for enterprises, construction standards, acceptance criteria. At the same time doing training, better .promotion U-PVC tube. <br> IV. concluding remarks <br> U-PVC tube as a new kind of urban water supply tube to tube, it has advantages in water supply project in the increasingly widespread, in production also need wrap- .up, further improvement of sound technical specifications and related standards, u-PVC pipes application promotion to make a greater contribution. The above is in construction practice of making, deficiencies, peer correction..