【 Weak current College 】 no discussion on the application of vacuum equipment for water supply

【 Summary 】 article is targeted at non-vacuum equipment for aquatic background, characteristics, classification and application currently markets analyzed, it is recommended that early establishment perfect market access system and uniform industry standards and specifications, so that no negative pressure water supply equipment market healthy development.

【 Words】 no negative pressure water supply system; market access; industry standards and specifications
　　
With the development of the city, the second municipal water pressure pump station is residential and urban high-rise building water is an indispensable component of this is because the local water distribution system water pressure is not high enough, could not put water directly to the senior user, so you must first be municipal tap water discharge to water tank or water, then second booster pumping station will supply water to the user, to ensure that every user of water requirements. But due to mismanagement, pool, water tank and lack of regular cleaning and disinfection measures fail twice, as well as the defects of the system itself, causing secondary pollution of water quality has a direct impact on water safety, even serious water pollution accidents. Therefore protect secondary pressure pump station of potable water quality and safety is not only the health, water supply, water supply company, a top priority for the Government sector, and is also a user management units and water supply equipment manufacturers need to figure out. In addition, with the height of the national economy development and social progress, the water company water supply capacity strengthening, has scheduled a quantitative water supply has become history, but also for the development and manufacture of new environment-friendly energy supply equipment provides decisive criteria.
It is in the above context, no-pressure water sharing equipment of the successful development and introduction of a market made up for the inadequacies of traditional water supply. China's first non-vacuum water supply equipment in the mid-1990s and the successful development of the market, but because of the water supply system of regulatory requirements and consumer perception of the lag, no negative pressure products haven't been able to get promotion. In the town water supply Ordinance had stipulated: "the prohibition in the urban network of public water supply pipeline directly pumped. " This is because the pumping time of vacuum interfere with hydraulic regime, the impact on the surrounding water, or even network damage. So in the engineering design to build a pond when first or water tank with pump pressure water supply pipe network to the user. Until 2003 the "SARS" period, people only secondary water pollution severity have a clear understanding, especially after Beijing local area after use, no-pressure water supply equipment have completely resolved secondary water-pollution, save energy, etc., and finally aroused widespread interest. In 2004, the Beijing Municipal Government file above the town water supply Ordinance related articles of the lifting of the ban, Shandong provinces followed unveiled details of the trial. Now these products in Beijing has nearly 1000 sets of products in use, Shandong province, Fujian province, Tianjin, Guangzhou, etc. larger regional application also. Coupled with this device in energy, water, land, construction funds, has significant advantages, became the place of water tank, water tanks, and other traditional secondary water supply facilities in the preferred device, causing a sudden warming market demand.
No negative pressure water supply system is in traditional frequency conversion water supply system developed on the basis of a new water supply, it is not a water pump, pipe fittings, valves, tanks and control cabinet of simple combination, but a set of mechanics, electronics, information and control technology as one of the high-tech products. With no negative pressure water supply in-depth conceptual development, more and more scientific research and production enterprise on non-vacuum technology for in-depth research, and scored. Domestic non-vacuum technology according to market an existing non-vacuum water supply equipment works, no-pressure water supply system is mainly composed of variable speed pump, steady flow compensator, vacuum suppressor, pressure and flow sensors, preloading since balancer, control cabinet, filters, backflow device components. According to the implementation of the principle of non-vacuum function, generally can be divided into the following forms:
(A) stationary stream compensators and vaccum suppressor control mode
When the municipal water supply pipe network or user consumption greater than municipal pipe supply capacity, vacuum suppressor open, steady-flow of air into the Compensator, the originally closed becomes river water compensators, suppression of vacuum generation, others in a steady stream of compensator setting liquid level control, when less than low position, pump stop working.
(Ii) automatic current limiter mode
When the municipal water supply pipe network or user consumption greater than municipal pipe supply capacity, through pressure sensor signal feedback, take limit frequency converter, the pump does not excess water, when the municipal supply meet demand, the system back to normal.
(3) pressure control mode
When the municipal water supply pipe network or user consumption greater than municipal pipe supply capacity, straight up variable flow pump constant pressure water supply to meet the requirements, the system back to normal.

Despite the fact that no negative pressure water supply equipment enterprises have developed rapidly over the past few years, but it's in the relevant standards and technical links etc or there are insufficient: first of all, its application has certain limitations. Because it is missing a second storage device, municipal water supply in case of failure, the device stops running and is shut off, so for those who cannot stop water supply of special users, it does not apply. Secondly, because it is a new type of equipment, technical links has yet to be further developed, application conditions are also to be municipal water supply conditions change and continuous improvement. Once again, the more critical point, the entire industry, no national uniform standards to follow, viable, various enterprises according to your own corporate standards for production, so the actual application process will inevitably be some problems. According to incomplete statistics, the now non-vacuum equipment manufacturing enterprises have from three to four years ago ten home soared to nearly one thousand. These enterprise-scale size, technology and service also vary, the biggest asset of 100 million Yuan, has advanced digital production line, small, only a dozen or so people hand made production, technical factors aside, the gap between its quality may be a world of difference. Just how to make the product does not have a negative one, all the way to the enterprise use, resulting in uneven quality of products. Additionally the device is under certain conditions, to apply pressure to the network, water supply,A set of requirements, but some companies ignore these requirements, the appointed water intake in one place, pumping excess, resulting in insufficient water supply. So if unrestricted allows non-vacuum devices access network, it is possible to make the network more than tolerance, it is also possible to fly the inferior products market, to the user and network security vulnerabilities.
Because no negative pressure water supply equipment has the particularity and importance of the masses of the life and health, so now no negative pressure condition of water supply equipment industry. Therefore, the necessary measures are: first, to reference the successful experience abroad and the practical application of the domestic situation, as soon as possible to develop national standards and norms to guide enterprise production and management, and encourages the enterprise of independent innovation, be developed both in line with national standards and the enterprise features of advanced technology, excellent product quality, and enhance service awareness and participation; and secondly to protect intellectual property rights, to examine the source of enterprise technology to eliminate those plagiarism technology, illegal acts against intellectual property; once again should establish scientific, rational enterprise access conditions, by one or several enterprises monopolize the market is certainly not conducive to technology improvement and advancement of industry, but because of the influx of the same swarm is not the true interpretation of the market economy. Therefore reference and related (172 pages under Add) (continued from p. 171) industry, the size of the enterprise capital, production conditions, the technical force, after-sales service to develop a mandatory targets, qualified enterprise mainly engaged in the project must be of a water supply products, which ensures the strength and production enterprises or their products and their take on the responsibility of the service, but also conducive to match industry orderly, specifications development; last should develop a real sense of Association, the association with the enterprises join hands to develop rules of the game, the maintenance of users, enterprises and national interests, to ensure that the industry can benefit from the sustainable development. Through the above measures, believe that the direction to guide social investment, to non-vacuum industry, consumer interests and intellectual property protection and the healthy development of the national economy will have a positive meaning, so that no negative pressure water supply equipment for the use of more science, more rational, more ecological, more energy efficient, truly benefit the masses.
【 References 】
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