Instruments that measure fluid flow are collectively referred to as flow meters or flow meters. The flowmeter is one of the important instruments in industrial measurement. With the development of industrial production, the accuracy and range of flow measurement requirements are getting higher and higher, and the flow measurement technology is changing with each passing day. Various types of flow meters have been introduced to suit various applications. More than 100 flow meters have been put into use. From different perspectives, flow meters have different classification methods. There are two commonly used classification methods. One is to classify according to the measurement principle adopted by the flowmeter: the second is to classify according to the structural principle of the flowmeter.
Sort by measurement principle
a. Mechanical principle:
Instruments belonging to such principles have differential pressure type, rotor type using Bernoulli's theorem;
Impulse type using the momentum theorem, movable tube type;
Direct mass equation using Newton's second law;
a target using the principle of fluid momentum;
Turbine using the angular momentum theorem;
Vortex type using vortex principle of fluid oscillation;
Use the total static pressure difference of the pitot tube type as well as volumetric and sputum, trough and so on.
b. Electrical principle:
Electromagnetic,
Differential capacitor type,
Inductive,
Strain resistance type, etc.
c. Acoustic principle:
Ultrasonic.
d. Thermal principles:
Thermal type,
Direct calorimetry,
Indirect calorimetry and so on.
Flowmeter product features:
Using intelligent judgment, the measurement correction setting is not used, and the air traffic control alarm and electrode detection application are more convenient;
Advanced "rough error handling" technology, which can remove fluids such as slurry to measure sharp disturbances, reduce output runout, maintain high precision measurement and make output more stable;
With a fluid density setting, it can display mass flow;
Constant current excitation current range, 125mA, 250mA optional, can be used with different manufacturers, different types of electromagnetic flow sensors;
Control function with remote reset of the totalizer, with contact signal input for starting and stopping accumulation, suitable for total inspection and batch processing applications;
With self-test and self-diagnosis function;
Advanced non-volatile memory for higher circuit reliability and effective protection of setup and measurement parameters;
The meter can be equipped with an unpowered clock and memory for recording the power down time, power-on time and power-down time;
The meter has an optional hour recording function that can store flow and electrode resistance measurements for more than 30 days.
The new keyboard processing method avoids the keyboard operation affecting the measurement, and can enter and return the operation menu to make the parameter setting more convenient;
The total display uses 10-bit decimal 9999999999 full-value carry, which solves the practice of double-word full value 4294967285 (hexadecimal FFFF) carry-in habit;
With wireless transmission, the mesh network is organized by the wireless HART protocol.
Executive Standard: JB/T 9248-1999
Nominal diameter: 15, 20, 25, 32, 40, 50, 65, 80, 100, 125, 150, 200, 250, 300, 350, 400, 450, 500, 600, 700, 800, 900, 1000, 1200, 1400, 1600, 1800, 2000, 2200, 2400, 2600, 2800, 3000
Maximum flow rate: 15m/s
Accuracy: DNl5~DN600, indication: ±0.3% (flow rate ≥1m/s); ±3mm/s (flow rate <1m/s)
DN700-DN3000, ±0.5% of the indicated value (flow rate ≥0.8m/S); ±4mm/s (flow rate <0.8m/S)
Fluid conductivity ≥5uS/cm
Nominal pressure:
DNl5～DN: 1504.0MPa, DNl5～DN600: 1.6MPa, DN200～DN1000: 1.0MPa, DN700～DN3000: 0.6MPa, Special order: 6.3, 10MPa
Ambient temperature
Sensor: -25 °C - ten 60 °C
Converter and integrated type: -10 ° C - ten 60 °C
Lining material: PTFE, neoprene, polyurethane, polytetrafluoroethylene (F46), screened PFA
Maximum fluid temperature
- Body type 70 °C
Separate type: Polychloroprene lining 80 ° C; 120 °C (specify when ordering)
Polyurethane lining 80 °C
PTFE lining
Polytetrafluoroethylene propylene (F46) 100 °C; 150 °C (specify when ordering)
Screening PFA
Signal electrode and grounding electrode material: stainless steel 0Crl8Nil2M02Ti, Hastelloy C, Hastelloy B, titanium, tantalum, platinum/rhodium alloy, stainless steel coated tungsten carbide
Electrode scraper mechanism: DN300-DN3000
Connecting flange material: carbon steel
Grounding flange material: stainless steel 1Crl8Ni9Ti
Import protection:
DN65—DNl50: Stainless steel 1Crl8Ni9Ti
Flange material
DN200～DNl600: Carbon steel ten stainless steel 1Crl8Ni9Ti
Shell protection
DNl5～DN3000 separate rubber or polyurethane lining sensor: IP65 or IP68
Other sensors, body flow meters and split converters: IP65
Spacing (separate type): The converter distance sensor generally does not exceed 100m