In order to make the electromagnetic flowmeter work stably and reliably, the following aspects should be noted when selecting the installation location:
1. Try to avoid ferromagnetic objects and equipment with strong electromagnetic fields (large motors, large transformers, etc.) to prevent the magnetic field from affecting the working magnetic field and flow signal of the sensor.
2. It should be installed in a dry and ventilated place to avoid sun and rain. The ambient temperature should be -20~+60°C, and the relative humidity is less than 85%.
3. There should be plenty of space around the flowmeter for easy installation and maintenance.
Installation suggestions:
The measurement principle of the electromagnetic flowmeter does not depend on the characteristics of the flow. If there is a certain turbulence and vortex in the pipeline, it will be generated in the non-measurement zone (such as elbow, tangential current limit or half-opening shut-off valve upstream). Nothing.
If steady-state eddy currents in the measurement zone affect the stability of the measurement and the accuracy of the measurement, then some measures should be taken to stabilize the flow rate distribution:
a.increase the length of the straight pipe before and after; b. use a flow stabilizer; c. reduce the cross section of the measuring point.
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.
Precautions before gas turbine flowmeter is enabled
Keywords: gas turbine flowmeter, Tianxin gas turbine flowmeter, gas gas turbine flowmeter
First, the precautions before the gas turbine flowmeter is enabled
In order to ensure trouble-free, safe start-up and commissioning of the ultrasonic flowmeter, the following pre-checks must be carried out:
1. Before starting the flowmeter officially, be sure to handle each leak point;
2. Check the power supply voltage on the terminal block and the corresponding positive and negative polarity;
3. Check the polarity of the frequency output lead connected to the RS485 converter;
4. Check whether the gas turbine flowmeter and temperature/pressure transmitter display are correct and reliable, including the installation direction and verticality of the flowmeter; the sealing performance of all joints;
5, wiring inspection: should be in accordance with the system wiring diagram provided by Jiangsu Tianxin Instrument Co., Ltd., check all wiring is correct.
Second, the gas turbine flowmeter projection operation steps
1. Open the bypass shut-off valve;
2. Open the flow upstream shutoff valve;
3. Slowly open the downstream shutoff valve of the flowmeter;
4. Slowly close the bypass shutoff valve.
Third, the gas turbine flowmeter stop table operation steps
1. Open the bypass shut-off valve;
2. Turn off the downstream shutoff valve of the flowmeter;
3. Close the flow upstream shutoff valve;
Fourth, gas turbine flowmeter use precautions
1. The newly installed or repaired pipeline must be purged. When purging the metering line, the flow meter must be removed and the corresponding short section replaced the flow meter for purging.
2. When the gas turbine flowmeter pipeline is put into production, it should be slowly boosted and gradually increase the flow rate. When the production is stopped, it should be slowly depressurized.
3. Check the sound of the gas turbine flowmeter or the vibration of the casing during operation to determine whether the turbine blades and bearings are working properly. At low flow rates, attention should be paid to the change in sound, and the vibration of the casing is observed at high flow rates.