Pressure and temperature selection
The actual working pressure of the fluid in the pipeline should be less than the rated working pressure of the flowmeter. Pay attention to whether there is negative pressure in the pipeline, such as the evaporation process, and the negative pressure is up to -60KPa. Such working conditions should be communicated with the manufacturer's technicians when ordering. Strict requirements are imposed on the lining material. The actual temperature should meet the temperature requirements specified by the flowmeter.
Power supply selection
The choice of the electromagnetic flowmeter power supply should be selected according to the flowmeter itself and the environment of the site. If the site allows, the power supply is convenient, safe and easy to maintain. As a chemical company, more than 90% of the raw materials and process links are in the liquid phase. During operation, the internal humidity of the workshop is large, and no flammable gas is generated during the whole operation. It is safer to use DC24V for power supply. Outdoor dry environment, choose AC220V power supply, convenient lead wire, good maintenance and low cost.
Some explosion-proof occasions, such as flowmeters used in gas boilers, are ideal for battery-powered electromagnetic flowmeters.
Advantages of turbine flow meters
The pressure loss is small, and the impeller has anti-corrosion function;
1.Adopt advanced ultra-low power single-chip microcomputer technology, the whole machine has strong functions, low power consumption and superior performance.
2.Intelligent flow display with nonlinear accuracy compensation. Correction formula accuracy is better than ±0.02%
3.The meter factor can be set online by button and can be displayed on the LCD screen. The LCD screen is intuitive and clear, and the reliability is strong.
4.EEPROM is used to accumulate the flow and the meter coefficient is powered down. The protection time is more than 10 years.
5.Using high-performance MCU central processing unit to complete data acquisition and processing display output, cumulative flow instantaneous flow
6.The screen displays a convenient man-machine interface for data transfer in standard 485 format.
7.Fully hard alloy (tungsten carbide) shielded cantilever beam structure bearing, integrating rotary bearing and pressure bearing, greatly improving bearing life and working in medium with a small amount of sediment and dirt.
8.It adopts 1Cr18Ni9Ti all stainless steel structure (the turbine adopts 2Cr13) and has good anti-corrosion performance.
9.Easy to maintain, self-rectifying structure, small and light, simple structure, which can be combined in a short time.
10.Internal cleaning is simple.
11.Strong anti-magnetic interference and vibration capability, reliable performance and long life
12.The lower limit flow rate is low and the measuring range is wide.
13.The on-site display type LCD screen is clear and intuitive, with low power consumption. The 3V lithium battery can be operated continuously for more than 5 years.
Corrosion resistant, suitable for acid and alkali solutions
Fourth, the liquid turbine flowmeter put into operation the opening and closing sequence
1. The sequence of opening and closing of the operation
For flow sensors without a bypass line, first open the flow sensor upstream valve at a medium opening and then slowly open the downstream valve. Run at a small flow rate for a period of time (eg 10 minutes), then fully open the upstream valve, then open the large downstream valve opening to adjust to the required normal flow.
The flow sensor equipped with the bypass pipe first opens the bypass pipe valve to open the upstream valve at a medium opening degree, slowly opens the downstream valve, and closes the opening of the small bypass valve to make the instrument run for a period of time with a small flow rate. Then fully open the upstream valve, fully close the bypass valve (to ensure no leakage), and finally adjust the downstream valve opening to the required flow.
2. Activation of low temperature and high temperature fluids
The low-temperature fluid pipeline should drain the water in the pipeline before the flow, and then run for 15 minutes at a small flow rate, and then gradually increase to the normal flow. Slow down when stopping, so that the pipe temperature and ambient temperature are gradually approaching. High temperature fluid operation is similar to this.