The mediums that need to be measured in the site are different. Now, a brief introduction is made on the selection of flow meters for different media.
The selection of large water flow meter: suitable for electromagnetic flowmeter, ultrasonic flowmeter. Other applications such as vortex flowmeters, orifice flowmeters, etc. have faded out of this application, and these two types of flow meters are the most important in the industry. In particular, it should be mentioned that the application of Kaifeng Shengda's plug-in flowmeter and electromagnetic flowmeter are better.
Sewage, pulp and other turbid liquid meter selection: electromagnetic flowmeter can be used. However, when choosing an electromagnetic flowmeter, consider that the liquid does not contain more air or bubbles.
The meter with more bubbles of liquid selection: Doppler ultrasonic flowmeter can be selected, using this type of flowmeter to measure the fluid with bubbles, the effect is very good.
Flow meter selection with low conductivity such as pure water and demineralized water: Turbine flow meter is very suitable for measuring such fluids.
Flow meter selection for strong corrosive media such as acid and lye: 1. Electromagnetic flowmeter with acid and alkali lining. 2. clamp type ultrasonic flowmeter.
Selection of flowmeters for mediums with large concentration and large solid particle content such as mortar and electric powder slurry: electromagnetic flowmeter.
Flow meter selection for oil media such as oil and diesel: turbine flow meter and ultrasonic flow meter.
Gas flow meter selection: vortex flowmeter.
Third, gas turbine flowmeter daily inspection
1. Look at the display: Observe the total amount, instantaneous, temperature, pressure, and battery power. If the abnormality is reported in time.
2. Listen to the running sound of the flowmeter. (Method) The flowmeter should have no noise when it is running normally. If there is a large abnormal noise, it can be judged as damage to the movement of the movement (for example). It needs to be reported and processed in time.
3, data comparison, the output of the first 3 to 5 days before the statistics, if there is no major change, the flowmeter runs normally, such as the successive decrement phenomenon, the gas turbine flowmeter impeller (shaft, shaft core), filtration There is a problem with the device. Need to be reported in time for processing
4, gas turbine flowmeter filling lubricant
(1) Instrument refueling is an important part of the daily maintenance work of the instrument. Lubricating oil is mainly for instrument bearing; lubricating oil can protect the instrument bearing, reduce friction, reduce wear and prolong the operation cycle of the instrument;
(2) Regularly adding lubricating oil can effectively reduce the maintenance rate of the instrument and reduce the maintenance cost;
(3) Ensure the measurement accuracy of the flowmeter. "Measuring is counting money." why would you said this? The management of production and operation accounting, energy saving, cost accounting, etc. is an important production link of enterprise management. If the measurement is not in place, it will affect the economic efficiency and reputation of the enterprise. Therefore, the daily maintenance of the instrument is very important.
Second, choose from the type of flow meter
Various flow meters, such as volumetric flowmeters, speedmeters, and differential pressuremeters, have different characteristics. Different flowmeter types have different turndown ratios. The turbine flowmeter has a turndown ratio of 1:20 to 1:30, the Roots flowmeter has a turndown ratio of 1:20 to 1:160, and the film gauge has a turndown ratio of 1: 160 (The error characteristic curves of these three kinds of flow meters are shown in Figure 1), and the appropriate flow meter should be selected according to the actual situation.
By comparing the error characteristics of the above flowmeters, it can be seen that the starting flow of the membrane meter and the Roots flowmeter is small, the initial flow of the turbine meter is relatively large, and the membrane surface exhibits a positive deviation in the small flow state. The Roots flowmeter exhibits a negative deviation. At low flow rates, the gas supply company is more willing to select a membrane meter for metering.