Flowmeter is a very common use of liquid flow measurement instruments in industrial and agricultural production, environmental protection, energy measurement, transportation and many other fields will see its figure, the correct rational use of flow meter for the national economic industry development provides a reliable guarantee. Due to the presence of factors involved in the working process of artificial flowmeter, so by the different factors in the use of phase interference will decrease the measurement accuracy, for the comprehensive utilization of various resources measurement and distribution mechanism is quite disadvantageous. As a professional manufacturer of the instrument, the instrument has a considerable understanding of the use of various types of flow meter. The analysis of this paper can be used to understand the function of the flowmeter, and the related factors that affect the accuracy of the flow meter.

As we know, the core measure of industrial development, for the accurate measurement can realize the standardization of production, it is particularly important to reduce material consumption problems of various processes, can enhance the comprehensive utilization efficiency of various resources. With the popularization and application of flowmeter in various fields, people are more and more high precision of the flow meter, which is the basic condition for the following operation. Therefore, the operator must ensure that the flow of the flow direction of the regional resources can be better with the accuracy of the flow meter. This is also the meaning of the content of this article.

Function analysis of flow meter

Measurement operation is a water conservancy project must have the control content, through measurement can grasp the actual situation of water resources use, for local resources allocation and utilization of advanced guidance. As early as in the ancient water conservancy projects, the use of water resources has been related to the measurement system, convenient for the daily distribution of drinking water. So far, our country has adopted more types of flow measurement instruments as a measurement tool, the main function of the flowmeter:

1, measurement function. Measurement is the leading power of modern industrial production, all industrial production activities must be completed under the specific conditions in order to achieve the standardization process of industrial production. Using the meter as the instrument device, can improve the overall efficiency of industrial resources regulation, the water use plan for each project has produced a clear measurement system. For example, the urban drinking water distribution system uses flow meter as the main control tool, time and quantity to measure the water demand, and the water should be used to achieve good results.

2, guiding function. Industrial instrument is to better guide the production, and obtain the data content related to the actual application of resources, reasonable guidance to all kinds of data operations. Flow meter guidance function is mainly reflected in the water resources control scheme, with the help of the instrument facilities can be set up special guidance for the water supply operation of hydropower station, and accelerate the reform of the regional resources. For example, a regional industrial and agricultural water allocation scheme, the two major industrial water consumption, distribution programs are significantly different, the use of flow meter can guide the use of water resources, water pollution monitoring program, the flow meter for industrial sewage, sewage and other guiding role, improve the operation efficiency of flue gas emissions, sewage treatment.

Two, the relevant factors that affect the accuracy of the flow meter

At present, whether it is industrial or agricultural water use, the use of data to measure the flow of data for the reference, to further the preparation of feasible water use mechanism. Flow meter is a common tool for modern industrial measurement, and it can get accurate data for the professional personnel to perform the operation according to the standard. However, the flow meter is also faced with different stability in the use phase, the low accuracy coefficient is a relatively common phenomenon, this problem will affect the final water allocation efficiency. According to the author's work experience, the factors that affect the accuracy of the flow meter include personnel, instrument, data, etc..

1, instrument factor. With the deepening development of Industrial Science and technology research, product type flowmeter more style, only from the flow meter division, flow meter can be divided into rotor flow meter, throttle flowmeter, slit flowmeter, volumetric flowmeter, electromagnetic flowmeter, ultrasonic flowmeter and weirs. If according to the media, the main liquid flow meter, gas flowmeter. Each kind of flowmeter use range is different, if the choice of instrument product does not meet the actual application requirements, the overall measurement will reduce the standard coefficient of the income data, the uncertainty of the accuracy of the flowmeter, greatly affect the accuracy of the use of the instrument operation.

2, personnel factors. As professional instruments in industrial production, environmental protection, energy measurement and other operations, the use of flow meter has professional standards, and the measurement of the operational process is not standardized, not professional, not uniform, it is the subjective factor to reduce the accuracy of traffic flow calculation. Taking water conservancy survey as an example, the survey personnel set up the instrument position, measuring range and other operational errors, misleading the measurement and control process, the final data and the actual measurement indicators have a big difference. In addition, the personnel of the instrument is familiar and blind control, but also reduce the accuracy of the instrument.

Three, improve the accuracy of the use of the comprehensive measures

Flowmeter is an indispensable instrument in the development of national economy. It can realize the optimal allocation of resources and provide reliable data reference for industrial production, environmental protection and energy distribution. In view of the problems existing in the use of the above flow meter, we must adjust the instrument control to improve the accuracy of the flow meter measurement. In order to introduce the precision control measures in detail, several kinds of flow meters are mentioned in this paper.

1, throttle device. The accuracy of this kind of instrument is generally do not need fluid calibration, the factory inspection more than the "dry standard" method, the basic accuracy is able to calculate. The calculation is based on the provided "ratings", the density of the medium can be used for automatic compensation, intelligent display, this case is the need to focus on the instrument installation site is in accordance with the requirements of the instrument, such as the length of straight pipe, if not up to the requirements of the calculation and error to reference the instrument the instructions.

2, volume type flowmeter. In the actual working condition, the additional error caused by the volume type flowmeter is usually due to the influence of temperature and pressure of the fluid medium to the volume of the cavity, and can calculate the volume of the change. The viscosity of the actual fluid may have an effect on the meter reading, according to the manual of the instrument to consider, as far as possible the establishment of automatic flow data processing mode. The establishment of automatic measurement and control mode, fully embodies the characteristics of a number of flow meter.

3, electromagnetic flowmeter. The internal diameter of the electromagnetic flowmeter sensor (flow area) has an effect on the measured value, the pressure temperature of the fluid medium is different from the reference condition. The instrument measures the volume flow in the working condition. If the volume flow or mass flow in the standard state, it is still necessary to carry out the density compensation, and the accuracy coefficient is further tested according to the instrument work.

4, turbine flowmeter. This instrument is sensitive to the condition of the field. When the temperature and pressure of the fluid medium are different from the reference conditions, the volume changes of the sensor casing can be calculated according to the material and temperature pressure. When the viscosity of the fluid medium and the viscosity of the calibration fluid vary greatly, it should be corrected according to the viscosity correction curve provided by the instrument manufacturer, which can improve the accuracy of data transmission.

5, vortex flowmeter. When the temperature, pressure and reference conditions of the fluid medium are different, the volume changes of the sensor casing can be calculated according to the material and temperature and pressure of the sensor. The vortex flowmeter is a high demand on the upper and lower reaches of the straight length, especially in high precision requirements of users, if you want to know the standard volume or mass flow, also need to constantly optimize the density compensation, data flow meter.