Choice of caliber
The choice of the diameter of the electromagnetic flowmeter is not necessarily the same as the diameter of the pipe, and should be determined by the flow rate and flow rate. However, as the chemical raw materials and intermediate liquid of Salt Lake, the viscosity is large and the flow rate is low (generally 2.0 to 4.0 m/s). The electromagnetic flowmeter is used on such a pipe, and the diameter of the sensor is the same as the diameter of the pipe. If the flow rate is lower than 1.0m/s, an electromagnetic flowmeter of appropriate flow rate can be selected to ensure measurement accuracy and relatively reduce investment.
Selection of flow rate and range
Basically, they are anti-corrosion plastic pipes, and considering the lining of the flow meter, the flow rate is generally controlled at 2m/s. For some materials that are easy to crystallize (such as sodium carbonate solution, compounding liquid: crystallized mainly boron and magnesium double salt), the flow rate is increased to 3.0 to 4.0 m/s by taking measures. The flow rate will increase the flow noise, and the vibration of the pipeline will affect the measurement accuracy. Under the condition that the electromagnetic flowmeter is installed, the shock absorber should be installed before and after. The full scale of the meter is greater than the expected maximum flow value, which is typically 1.2 times the estimated maximum flow. The normal measurement flow is greater than 50% of the full scale of the meter to ensure a certain measurement accuracy.
The main technical parameters of ultrasonic external clamp flowmeter:
Measurement accuracy: better than 1%
Repeatability: better than 0.2%
Measurement period: 500ms (2 times per second, 128 sets of data collected per cycle)
Working power: 220VAC/8~36VDC
Maximum flow rate: 64m / s (flow rate resolution 0.001m / s)
Display: 2 × 10 Chinese characters backlit LCD can display instantaneous flow and positive, negative, net cumulative flow, flow rate, etc.
Operation: 4×4 touch keyboard (F4 main unit magnetic 4 button) operation
Signal input: 3 channels of 4-20mA analog input, accuracy 0.1%, can input pressure, liquid level, temperature and other signals
2-way three-wire PT100 platinum resistor
Signal output: 1 isolated RS485 output
1 way 4-20mA or 0-20mA output
1 channel isolated OCT (programmable between pulse width 6~1000ms, default 200ms)
1 relay output (pulse width 200ms)
Data storage: Optional built-in data storage (SD card) can store time, instantaneous flow, accumulated flow, signal status, etc., through special software, can import data into computer for statistical and management
Communication protocol: MODBUS protocol, M-BUS protocol, FUJI extension protocol, and compatible with communication protocols of similar products of other domestic manufacturers
Other functions: automatic memory before 512 days, the first 128 months, the first 10 years of positive / negative / net cumulative flow
Automatically remember the first 30 times of power-on and power-off time and flow rate, and can realize automatic or manual addition of traffic, which can be read by MODBUS protocol.
Programmable batch (quantitative) controller, fault self-diagnosis function
Software upgrade via code file transmitted via E-mail
Protection level: sensor IP68, F4 host IP68, remaining host IP65
Explosion-proof grade: EXdIIBT4 (JN-100F2 type)
Gas turbine flowmeter and screwing vortex flowmeter measurement difference
Keywords: gas turbine flowmeter, Tianxin gas turbine flowmeter, gas gas turbine flowmeter
First, the characteristics of gas turbine flowmeter and spiral vortex flowmeter
Gas turbine flowmeter and screwing vortex flowmeter are the main gas metering instruments in China. In foreign countries, almost no one uses gas to swirl into the vortex flow meter. At present, there are certain applications in the domestic vortex flowmeter. In terms of standard conditions. The international standard ISO9551 promulgated by the International Organization for Standardization and the international recommendations R6, R32 promulgated by the International Organization of Legal Metrology (OIML) have corresponding national standards and regulations in China and developed countries. The above documents guarantee the authority of gas turbine flowmeters in gas metering. Sex. Gas-introducing vortex flowmeters have not yet established relevant standards. It is difficult to guarantee the authority of the flow meter in gas metering. At present, in domestic flow meters for gas measurement, gas turbine flowmeters dominate, and the vortex flowmeters also have a certain market. The use of the two is similar, and users often have doubts about the choice of the two.