Vortex flowmeter selection
(1) Selection of vortex flow transmitter
In the measurement of saturated steam, VA type piezoelectric vortex flow transmitter is adopted. Because of the wide range of vortex flowmeter, in practical applications, it is generally considered that the flow of measuring saturated steam should not be lower than that of vortex flowmeter. The lower limit, that is to say, the fluid flow rate must not be less than 5 m/s. According to the size of the steam, the vortex flow transmitters with different calibers are selected, and the caliber of the transmitter cannot be selected by the existing process pipe diameter.
(2) Selection of pressure compensation pressure transmitter
Since the saturated steam line is long and the pressure fluctuates greatly, pressure compensation must be adopted. Considering the corresponding relationship of pressure, temperature and density, only pressure compensation can be used in the measurement, because the saturated steam pressure of Mingtong Company is 0.3-0.7MPa. Range, the range of pressure transmitter can be selected 1MPa.
(3) Display instrument selection
Display instrument intelligent flow display instrument with voltage regulation compensation, instantaneous flow display and cumulative flow accumulation function.
Electrode material
Corrosion resistance and wear resistance
Stainless steel: 0Crl8Nil2M02Ti is used for industrial water, domestic water, sewage and other weakly corrosive media. It is suitable for petroleum, chemical, steel and other industrial sectors as well as municipal, environmental protection and other fields.
Hastelloy B: has good corrosion resistance to hydrochloric acid at all concentrations below the boiling point, and is also resistant to corrosion by non-chlorinated acids, bases, non-oxidizing salts such as sulfuric acid, phosphoric acid, hydrofluoric acid, and organic acids.
Hastelloy C: resistant to non-oxidizing acids, such as nitric acid, mixed acid, or corrosion of mixed media of chromic acid and sulfuric acid, and also resistant to oxidizing salts such as Fe, ", Cu" or other oxidants, such as Corrosion of hypochlorite solution and seawater above normal temperature
Titanium: It is resistant to seawater, various chlorides and hypochlorites, oxidizing acids (including fuming sulfuric acid), organic acids and alkalis. It is not resistant to the corrosion of relatively pure reducing acids (such as sulfuric acid or hydrochloric acid), but if the acid contains an oxidizing agent (such as nitric acid, Fc++, Cu++), the corrosion is greatly reduced.
钽: Excellent corrosion resistance and glass are very similar. In addition to hydrofluoric acid, fuming sulfuric acid, alkali, it is almost resistant to the corrosion of chemical media (including boiling point of hydrochloric acid, nitric acid and sulfuric acid below 50 ° C). Antimony in alkali; corrosion resistant.
Platinum/titanium alloy
Almost resistant - cut chemical media, but not for aqua regia and ammonium salts.
Stainless steel coated tungsten carbide
For non-corrosive, strong abrasive media.
Note: Due to the wide variety of media, its corrosiveness is affected by complex factors such as temperature, concentration and flow rate, so this table is for reference only. The user should make his own choice according to the actual situation. If necessary, the corrosion resistance test of the material to be selected, such as the coupon test.
Battery powered electromagnetic flowmeter features
1. Micro power consumption design, five 3.6V lithium batteries, continuous operation for 5~10 years, and easy to replace the battery.
2. The display adopts LCD large-screen liquid crystal display, which can display multiple flow parameters such as instantaneous flow rate, flow rate (pipe pressure), cumulative total amount of forward and reverse, and alarm prompt.
3. There are no movable and resistance parts in the measuring tube, no entanglement or clogging phenomenon, almost no pressure loss, and long-term reliable and continuous work.
4. Wide measurement range: The flow rate measurement range can reach 0.05m/s~10m/s.
5. High measurement accuracy: ±0.5% ~ ±1.0%.
6. Measurement stability: The measurement accuracy is not affected by changes in physical parameters such as temperature, pressure, viscosity and density of the measured medium.
7, with pulse output and GSM wireless data remote transmission.
8, with data storage function, up to 1000 groups of traffic data can be saved, and the data storage time can be arbitrarily set and data query.