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.
1. Requirements for straight pipe sections
Inlet/outlet straight pipe section: inlet should be ≥10×DN; outlet should be ≥5×DN
2. Grounding point requirement
In order to make the instrument work reliably, improve the measurement accuracy, free from external parasitic potential / the sensor should have good grounding, the grounding resistance is less than 10. (If the metal pipe is well grounded, no special grounding device is required) 3.3 Pair installation Location requirements as shown
Insert the electromagnetic flowmeter according to the situation of the pipeline in the field. If the flowmeter without the ball valve is installed, it should be installed on the pipeline without overpressure (that is, the flowmeter without the ball valve can be installed without pressure), and the hole is opened in the pipeline. Diameter 50, ready to weld the connecting welded pipe to the opening of the pipe; for occasions requiring constant flow loading or unloading or no media spillage, a ball valve must be installed, that is, a plug-in electromagnetic flowmeter with a ball valve structure is selected; With a diameter of 50, it is ready to weld the connecting welded pipe to the opening of the pipe.
Measuring range : Recommended range: 0.5m/s to 10m/s continuously adjustable. Maximum use range: continuously adjustable from 0.2m/s to 15m/s
Signal output: 1, the switch quantity can be set to: pulse output (up to 1000HZ); high/low flow alarm; empty pipe alarm; flow direction indication;
Fault alarm; 2, current output: 4-20mA output
Configuration method: 1. Field configuration through three manual keys. 2. Field configuration via remote control. 3. Perform on-site configuration through the handheld communicator.
Memory: The memory that the EEPROM does not disappear, no battery saving.
Flowmeter challenges
Traditional mechanical flowmeters, such as differential pressure flowmeters, positive displacement flowmeters, and variable area flowmeters, are already in the stage of popularization, with fierce price competition, decreasing profit margins, less technological innovation, and relatively mature markets. . Frost & Sullivan believes that achieving product differentiation and customized production is an important breakthrough for manufacturers in the fierce competition in mature markets. Based on Frost & Sullivan's analysis of the needs of industry users, the user community expects manufacturers to provide automated equipment that will bring tangible benefits to the production process. Users will have specific requirements in the application process, such as: application in the special environment of the petrochemical industry, the need for rugged design and explosion-proof certification; user demand for Coriolis flowmeter designed for straight pipe. How to effectively obtain the actual needs of users and improve the traditional products is a challenge to the manufacturer's differentiated and customized production process.
Guiding users to accept and use new technology flow meters, such as ultrasonic flow meters, electromagnetic flow meters, and thermal mass flow meters, is another challenge for manufacturers to make the market bigger and stronger. In fact, the new technology flowmeter mentioned above has been developed and applied more than ten years ago. How to make customers realize that using the new technology flowmeter can effectively improve the production efficiency is an important issue for manufacturers.
In addition, new technology flowmeters are constantly being introduced into various industries, and fast and efficient after-sales service is also crucial for manufacturers. In particular, the use of Flowfield based on Foundation Fieldbus and Profibus PA bus has certain requirements for software technology. Effective services can provide users with more suitable solutions and close to users.