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Applications of mass flow meters: Since mass flow meters measure the mass flow rate of a fluid, they are not affected by changes in parameters such as fluid temperature, pressure, or density. They also offer high measurement accuracy (up to 0.1%), and no straight pipe section is required. Therefore, they are often used for flow measurement in situations where precise measurements and strict control of feed rates are necessary, as well as for accounting purposes in trade transactions. However, due to their high cost, they are not widely used. Composition of a mass flow meter: It consists of three parts – the sensor, the transmitter, and the display unit. The sensitive element of the sensor is the measurement tube, which is installed within the pipeline. The transmitter and the display unit (simple models do not have a display unit) are installed separately next to the sensor in a location that facilitates observation and maintenance. A dedicated multi-core shielded cable is used to establish an electrical connection between them. Structural classification of Coriolis mass flowmeters: Based on the shape of the measurement tube, they can be divided into straight-tube and bent-tube types; based on the number of measurement tubes, they can be divided into single-tube and double-tube types (the double-tube type is commonly used). Installation requirements for mass flow meters: A. The installation location should not have any significant sources of vibration, and reinforcement measures should be taken to stabilize the pipes in the vicinity of the instrument ； B. It cannot be installed near devices that generate strong magnetic fields, such as large transformers, motors, and pumps, to avoid interference from those strong magnetic fields ； C. No stress should be present when the sensor is connected to the pipeline ； D. Straight-tube mass flow meters should be installed vertically; if horizontal installation is required, the two measurement tubes must be at the same level. E. When using a bent-tube mass flow meter to measure liquids, the bent section should face downward; when measuring gases, it should face upward. Methods for putting a mass flow meter into operation and shutting it down: A. Before putting a mass flow meter into operation, it is necessary to check whether its installation meets the requirements, whether the pipes have been thoroughly cleaned, and whether the pressure test has been completed ； B. After preheating for 30 minutes under power, start the fluid flow until the sensor temperature equals the operating temperature of the fluid; then close the downstream valve, ensure there are no leaks, and zero the flow meter when the pipe is full ； C. Open the upstream and downstream valves, close the bypass valve, and put the flow meter into use ； D. When the flow meter is out of use, for media prone to scaling, the drain valve should be opened to empty the medium from the flow meter; for media prone to solidification, the medium must be completely removed and the pipe should be cleaned with low-pressure steam or plant air to ensure that no medium remains inside the measuring tube.