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2021

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What is the flowmeter?

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The English name of the flowmeter is flowmeter, which is defined by the National Scientific and Technical Terms Review Committee as an instrument for measuring flow and/or representing the total amount of fluid within a selected time interval. In short, it is an instrument used to measure fluid flow in pipes or open channels.

 

Flowmeters include differential pressure flowmeter, rotary flowmeter, throttling flowmeter, micro slit flowmeter, volumetric flowmeter, electromagnetic flowmeter, ultrasonic flowmeter, etc. Classification by medium: liquid flowmeter and gas flowmeter.

 

Measurement is the eye of industrial production. Flow measurement is one of the components of measurement science and technology, which is closely related to national economy, national defense construction and scientific research. Doing this work well will play an important role in ensuring product quality, improving productivity and promoting the development of science and technology. Especially in the current era of energy crisis and the improvement of industrial production automation level, flowmeter plays a more prominent role in the national economy.

 

The unit m3/h commonly used in the project can be divided into "Flow Rate" and "Total Flow". Instantaneous flow refers to the amount that passes through an effective section of a closed pipe or open channel in a unit time. The flowing substances can be gases, liquids and solids. Cumulative flow refers to the cumulative flow of fluid through the effective section of closed pipes or open channels in a period of time (1 day, 1 week, 1 month, 1 year). The cumulative flow of time integration can also be obtained through the instantaneous flow, so the instantaneous flowmeter and the cumulative flowmeter can also be converted to each other.

 

There are many kinds of flow measurement methods and instruments, and there are also many classification methods. Before 2011, there are 60 types of flow meters available for industrial use. The reason why there are so many varieties is that there is no flowmeter applicable to any fluid, any distance, any flow state and any service conditions. However, with the development of the times, in this era of technology explosion, a new product mass flowmeter has finally emerged. The mass flowmeter can be applied to any fluid, any distance, any flow state, and any service conditions, but not just because the price is relatively expensive

 

There are more than 60 kinds of old flow meters, each of which has its specific applicability and limitations. There are two main categories by measurement object: closed pipe and open channel. According to the measurement purpose, it can be divided into total amount measurement and flow measurement, and its meters are called total amount meter and flowmeter respectively.

 

The flowmeter performance, fluid characteristics, installation conditions, environmental conditions and economic factors can be considered. The details of the five aspects are as follows:

Instrument performance: precision, repeatability, linearity, range, flow range, signal output characteristics, response time, pressure loss, etc.

 

Fluid characteristics: temperature, pressure, density, viscosity, chemical corrosion, wear, scaling, mixing, phase change, conductivity, sound speed, thermal conductivity, specific heat capacity, isentropic index, installation conditions: pipeline placement direction, flow direction, length of straight line upstream and downstream of the sensor, pipeline diameter, maintenance space, power supply, grounding, auxiliary equipment (filter, air eliminator), installation, etc.

 

Environmental conditions: ambient temperature, humidity, electromagnetic interference, safety, explosion-proof, pipeline vibration, etc

 

Economic factors: instrument purchase cost, installation cost, operation cost, inspection cost, repair cost, instrument life, spare parts, etc.

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