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A mass flow meter is a flow measurement instrument that continuously measures the flow rate of the medium being measured, with the results displayed in weight-based units such as kilograms or tons. A mass flow meter cannot control the flow rate; it can only measure the mass flow of liquids or gases, and outputs the flow value via analog voltage, current, or serial communication. However, a mass flow controller is a device that can both detect and control. 1. Why do ordinary flow meters require straight pipe sections? Sufficient straight pipe sections allow the flow pattern of the medium to develop fully, resulting in a stable flow field as it passes through the velocity-type flow meter, thereby improving measurement accuracy ； For some flowmeters with numerous mechanical components, the straight pipe section reduces the impact of flow regime changes and extends their service life ； For some velocity-type flowmeters, the required straight pipe section upstream is 40 times the diameter! 2. Why do mass flow meters not require a straight pipe section? Pipeline flanges, reducers, expanders, flow regulators, elbows, and valves can all have an impact on the fluid ； All flow meters based on flow velocity have certain requirements regarding straight pipe sections, with the aim of making the conditions under which the flow meter measures flow similar to those used for laboratory calibration ； The mass flow meter has no relation to the flow velocity of the medium, eliminating the need for a straight pipe section entirely. 3. Installation location of the mass flow meter: Easy access to data; easy for daily maintenance; protection from direct sunlight; protection from vibrations; ambient temperature within specified limits; far away from devices that generate strong electromagnetic interference. 4. Installation orientation of the sensor: 5. Installation of the sensor pipeline: Avoid twisting/bending stresses; do not use the sensor to align the pipelines; do not use the sensor to support the pipelines; do not support it directly on the sensor. Downstream valves are used for zeroing. Elbows should prevent condensation water from entering the wiring box. The maximum cable length between the sensor and the transmitter is 1000 ft (300 m). There should be at least 0.6m of distance between the sensor and large transmitters or motors. Since the operation of sensors relies on electromagnetic fields, it is essential to avoid installing them in areas with strong interfering electromagnetic fields. The installation location should also be carefully selected to minimize vibration as much as possible. 6. Other factors to consider regarding installation: Installation of stop valves and control valves – To ensure no flow during zeroing, stop valves should be installed upstream and downstream of the mass flow meter to prevent leaks. The control valve should be installed downstream of the mass flow meter, with the mass flow meter maintaining as high a static pressure as possible to prevent cavitation and flashing. Installation – Pulsation and Vibration To prevent mechanical vibrations that occur within the process or from external sources, it is necessary to inquire with the manufacturer regarding the resonance frequency range of the mass flow meter provided. The manufacturer can also be consulted about the vibration conditions on site to determine whether measures such as the installation of pulsation dampeners, vibration dampeners or flexible connection pipes, or special mounting devices for the flow sensor, are needed. Installation – Preventing interference between mass flow meters. When two mass flow meters of the same model are installed in series, or when multiple mass flow meters are installed closely together in parallel (or in series), especially when they are mounted on the same support frame, vibrations of the measurement tubes can cause interference between the various mass flow meters, leading to abnormal vibrations. In severe cases, this can render the instruments unusable. Precautions should be taken during installation, such as: requesting the manufacturer to set a resonance frequency value that is different from that of the instrument ； Increase the distance between the flow sensors; do not place them on the same frame, rather use separate support frames for each one ； Flow sensor installed in the opposite direction ； Methods such as using vibration-damping materials for isolation between flow sensors are employed. 7. Loading and unloading measurement: In loading and unloading measurement applications, the sensor housing should be installed with its top facing up or vertically. A check valve should be installed downstream of the sensor to prevent backflow of the medium. The check valve should be installed as close as possible to the sensor. In some cases, the process medium cannot be completely removed from the pipes; in such situations, a flag-type installation is generally recommended. When loading or unloading the application, it is advisable to follow these operating steps: Install shut-off valves upstream and downstream of the sensor; Close the upstream valve; Open part of the downstream valve; Slowly open the upstream valve to release air and allow the medium to fill the sensor; Once the flow system starts measuring, slowly open the downstream valve until it is fully open.