Several factors that make meter accurate

The instrument that measures the amount of water used by the user is a water meter, which is the basis for the user to pay the water fee. Urban water supply requires the use of a large number of water meters. The operating profit of the water supply company is inextricably linked to the accuracy of the water meter measurement. This is also an important part of our work to reduce the water leakage rate of the pipe network. How to make a good measurement accuracy of water meters, we must first clear certain conditions and factors to ensure accurate measurement of water meters.

1 The quality of the water meter and the quality of the water meter are directly related to the accuracy of the meter. The selection of the meter directly affects the use of the meter. We must use qualified and high-quality water meters, and the water meter diameter should be selected so that the user's normal water flow is between the nominal flow rate and the initial flow rate of the water meter. The diameter of the water meter cannot be determined simply by the pipe diameter.

2 Water Meter Verification Before the meter is used, it must be tested one by one or sampled to detect and repair or remove water meters that are permanently inaccurate due to various factors. The so-called permanent inaccuracy is the water meter in the installation before the outlier and due to external factors make the water meter movement and accessories wear and damage.

3 Installation quality of the water meter The installation quality of the water meter is an accurate precondition for water meter metering, including the selection of installation location and environment, and the technical requirements of the installation process. Common influencing factors are the following.

(1) The damp surface or corrosion of the gas easily corrodes the water meter.

(2) Long-term exposure makes it easy for water to emanate in the water to affect metering. Not only does condensation on the dial prevent water metering and it is easier to grow mosses.

(3) The vibration of the outside world makes it easy to wear the water meter movement.

(4) Non-standard installations, such as the installation of a water meter that must be installed horizontally or the front and back pipes of the meter group are not on a horizontal surface, and the water meter does not meet the requirements of the straight pipe before and after the water meter will affect the normal metering of the water meter.

4 Water Supply Quality The better the water meter is, the more accurate the water meter will be, and the worse the water quality will be, the greater the meter deviation will be, and the water quality will adversely affect the accuracy of the meter. There are two cases: First, the solid impurity particles entrained in the water, such as gravel, hemp, and the peeling of the inner wall of the pipe. Second, the water contained in the machine exceeds the standard, such as iron salt, etc. easily in the filter, impeller box adjustment hole, water inlet hole scale, when the water contains algae high, easy to grow moss in the dial.

5 The service life of water meters Based on extensive investigation and understanding of the use of water meters over a certain period of time, the mechanical performance will be reduced, and the rotation of the water meter tends to be slow. This leads to factors such as external environment, installation quality, and water quality, as well as the performance of the water meter itself.

6 Others If the pressure of the pipe network often changes, it will also cause the water meter movement to wear out. The mixing of air in the water meter will make the water meter faster. If the user does not use it continuously, opening and closing the water tap will cause an abnormal difference. At the same time, the water meter caused by the above situation Turning and rotation phenomena and man-made damage to the water meter and so on. To this end, to ensure the accurate measurement of water meters, we must take appropriate measures in accordance with the above circumstances, as follows.

(1) When selecting a high-quality water meter, the quality of the water supply and the change in water pressure must be considered comprehensively. Products with high accuracy, practicality, low resistance and durability must be selected as far as possible. We have conducted several on-site investigations and found that, in particular, the rust on the internal and external surfaces of the water meter below the DN50 is severe. Therefore, it is hoped that the internal material of the water meter or the 3232 can have anti-rust ability.

(2) Dynamic selection of water meter model. In general, for households with stable water consumption, they will not be changed after determining the diameter of the water meter on the initial loading water meter. However, if the water consumption of factories, stores, etc., varies greatly with changes in the production process, operating efficiency, etc., we must establish The water tracking mechanism is used to timely analyze and consider the necessity of changing the specification of the water meter according to the change of water quantity. For example, the initial installation of the meter is DNl50, but in the past six months, the amount of water used has only reached the amount of DNl00 caliber water meter, then you can consider Replace the water meter specifications.

(3) Check the water meter. Early detection, early repair and early replacement.

(4) Installation of water meters and precautions for installation Water meter installation principles: to ensure the accuracy of metering, it is easy to copy and remove water meters.

1 The water meter group adopts surface-mounted equipment, but no surface-mounted equipment is allowed to be concealed but the well requires that the water in the well be discharged in time. The well cover requirements can prevent the infiltration of rainwater on the ground, such as raising the height of the well cover, or using a double-layer well cover (outer layer is commonly used Pressure resistant manhole cover with a solid cover with a convex shackle.

2 The water meter should be placed in a cool and dry place as far as possible to avoid direct sunlight. A meter box can be built for the residents' row of outdoor water meters. In the past, the steel case was easy to rust, heavy, and easily damaged, and the cost was not low (the price of each meter box was 540RMB). If we could find a plywood box or a plastic box, we couldn't prevent it from being used. .

3 When installing the water meters side by side, you must leave enough space to open the cover.

4 before and after the water meter must ensure that the straight section requirements: the length of the straight section upstream of the water meter is 8D ~ 10D, the downstream not less than 5D (D is the nominal diameter of the water meter); when the straight section can not meet the requirements, (such as caused by the centrifugal pump after the bend Situation) The rectifier must be installed in front of the straight pipe section. The valve adopts a copper core valve, and requires the front and rear parts of the water meter, such as valves, retractors, check valves, etc., and their respective opening and closing do not affect each other.

5 The water meter must not be pressurized, and it must not be disassembled and disassembled. The water meter must be protected from strong vibration during transportation. Handle it with care.

6 Before installing the meter group, the construction pipeline must be flushed and the air inside the tube must be excluded.

7 After the water meter set is installed, the filter must be cleaned periodically.

(5) Improve water quality. It is necessary to strictly control the turbidity of the factory water, prevent the filter from leaking sand, and regularly clean the clean water tank. At the same time, strict implementation of the rules relating to flushing and effluent discharge in pipeline laying and repair, increase the quality of the coating on the inner wall of the pipeline, and update the old pipe network.

(6) The problem water meter should be promptly replaced and dealt with promptly. The water meter that exceeds the service life must be forcibly replaced. The state stipulates that the water meter with a caliber of 15 mm to 20 mm must not exceed 6 years, and the water meter with a caliber of 25 mm to 50 mm should not exceed 4 years. Therefore, in order to reduce the leakage rate of the water supply network, it is necessary to strengthen the management of the water meter while strengthening the management of the pipe network, and to do a good job of daily maintenance. Serious efforts must be made to ensure the accurate metering of water meters. At present, with the development of science and technology and the needs of society, new types of water meters are continuously available. There are large-diameter horizontal spiral-wing water meters and vertical screw-type water meters that are suitable for modern remote meter reading, remote monitoring, and centralized management. A small-caliber intelligent water meter. How to ensure the accurate metering of these meters is the key to the use and management of water meters by water supply companies. Water companies must continuously summarize and continuously improve the use of water meters.