【 Weak current College 】 meter's rotation causes and control

Abstract: this paper for work in the meter's rotation, analyzed the resulting rotation of reason, and several more effective solutions made a brief introduction.

1. the background as the MOC requirements for water supply enterprises to meter reading to households, a household, one table at national city water enterprise in full swing, so that is reduced by many users and water supply enterprises old conflicts, such as total table does not match the leaking water disputes and sufficient water pressure pipe online and user home water pressure problems. But as one household, a table work continued to deepen, and produced many new problems, meter installation location, the winter warmth, meter reading and the meter's rotation, but this particular problem is the first meter rotation.
In the early days because the user is always meter does not deal directly with the water supply companies, and the trend of indoor plumbing and water meter installation location is tiered installation, table and table spacing is large, user home piping arrangement is relatively simple, mostly only have a washing basin, a lavatory basin and a toilet, water meter produce rotation less likely. Therefore, the user has not reflected a water meter rotation problem. As living standards improve, house ware, piping arrangement is relatively complex, water consumption increases, with a table of one of the operators, users and the water supply enterprises directly between clearing water charges, and water prices are also rising. Thus, users are concerned about their own water meter runs, the rotation of this water meter is highlighted.
2. the rotation of the meter's rotation problem is caused by a variety of factors, this article from the characteristics of the water supply network and present the characteristics of the meter itself to analysis, mainly has following several causes:
2.1 pressure fluctuations, because water is a liquid, in the General case of physics characteristics is not compressed, but in tap water pipe, pipe pressure higher, then water will exhibit a certain compressibility. In tap water pipe, pressure fluctuations are inevitable, but currently our water meter is a mechanical watch, the water in which the flows of kinetic energy to spur gear operation, so as to achieve the purpose of measuring water. When no water, the water meter at both ends of the connection of the pipe is a certain amount of fixed pressure water; therefore, when the municipal pipe pressure rise after the table in the tap water volume increase due to pressure, this time there will be a trace of water through water meter, produce forward; when the pressure decreases, the table is compressed in the Shui reduced due to the pressure will be the expansion of water through the meter, as this is the reverse.
We all know, General machinery when the water table is entered on the drive gears forward and reverse when the water is motivated by the promotion of gear reverse, two-phase water drag, while the second head into the water, but reflect on the water meter readings are quite different. According to statistics, in the pipeline without air, resulting in very little water, about 0.5-1m3/month. Typically, this water users will not notice; at the same time, this is the measurement level normal results.
2.2 balloon, for this reason the rotation of the water. Tap water business was the production process of open construction, in the production process will dissolve in the water in a large number of gas, both in the construction process, the pipeline will also be brought into gas, if the pipe exhaust valve set unreasonable, gas will not be able to exclude. So if home long without water or pipeline design, the highest point in the pipeline or protruding point will produce a balloon. We all know, the compressibility of the gas is high, then if the pipe online pressure fluctuation, table space within the pipeline after expansion will be very large, so the meter's rotation rate. According to statistics, the resulting quantity from a few 2-3m3/month, more than a month there will be dozens of cubic meters of water. According to reports, statistics, existing users of water rotation phone 26, site survey process found that table has a balloon after pipeline whereas produce rotation of 21 families 80.8%, table 5 pipes leak after.
Therefore, at present most of the household water meter produce rotation phenomena are Canal due to a table in memory after the balloon.
2.3 installation and installation of quality
2.3.1 because most of the water meter out home now is a unit of the meter are concentrated in a box installed on the first floor. Considering that the winter cold, Frost and meter reading is convenient, with a 40 m-Φ Φ 50 m m m pipe received 6 or 12 meter, table and table spacing is small, and that the water meter set aside are also less straight pipe, this also affects water meter normal metering, water rotation.
2.3.2 installation quality, pipeline project basically buried in the ground or the walls, in the case of concealed work. National pipeline construction specifications provides for various pipe pipeline construction installation requirements, construction procedures, acceptance criteria and considerations, but the site construction, some managers and not complying with the requirements specification, there are some more or less caused pipe quality.
3. the solution
Before loading the table 3.1 check valve, given that the water meter rotation because of pressure fluctuations, caused by water is compressed, you can consider the installation of check valves, check valves can serve to prevent backflow of water. This pressure, the water is compressed, the resulting positive rotation meter; when the pressure decreases, the check valve closed automatically, the meter will not produce rotation. When the pressure rises again, as long as the pressure is not high pressure over the check valve, water meter won't go; water rotation mainly water meter only reciprocating metering accumulated several times out of a lot of water, the installation of check valves can reduce the frequency of rotation of a meter, which can be a good solution to pressure fluctuation caused by the rotation of the meter. However, due to residential water more frequently, and pipeline pressure fluctuation is relatively small, so the requirements check valves high sensitivity higher quality.
3.2 statistical analysis from the field investigation and treatment results, causing a meter to the rotation of the main reasons apart from indoor plumbing and leaking water apparatus mainly indoor plumbing installation not reasonable cause indoor pipes produce airbag, therefore in future work should be done.
3.2.1 in design-time features under rational arrangement of the exhaust valve pipe, timely analysis of exclusionary pipeOut of gas; new pipeline or a new installation of household water table for the first time, you should slowly open the valve, try emptying pipe air, reducing the air content in water.
3.2.2 on new meter installation, residents in the pipeline, the pipeline along the angle up laying, pipe-bending point reduction, discount points, and the highest point of the pipeline is often used in the design of a faucet, reduce pipeline network in the balloon.
3.2.3 on household reconstruction, in table water meter out home, you may void the user's home into the direction of change resulting in indoor stagnant water pipe segment appears in part, this part of the billing meter segment of "dead water" or higher, or pipe in pipe prominent, easy to produce airbags, in construction should be the removal or modification of the pipe.
3.2.4 meter out home is uninhabited, the pipeline has a lot of gas. Recommended that the water meter out home, to investigate the situation for the user, when the water meter installation acceptance, close no habitable user table after the valve meter and meter out home contract with the user when, and why. If you later need water to open the valve will be after the table.
3.3 from statistical analysis to see that the water meter rotation of the main reasons or by gas, therefore you can consider installing the exhaust valve. But higher prices due to the exhaust valve, and the location of the installation, piping layout and check valves require a higher sensitivity, etc., and also to network maintenance management is a certain amount of work, so unless it is necessary, as few installed exhaust valve.
4. conclusions
Cause water rotation for various reasons, but generally can be categorized into two: the first is subjective factors, namely human subjective, such as construction and acceptance, the human sense of the original gas leakage, etc., you can do this by strengthening the construction management, improve staff level and sense of responsibility to perfection. Second, objective factors, the main characteristics of the water itself, the pipe character and skill levels of development and other external objective factors, that regard must in future work in the trial and improvement can be improved.