Installation requirements for mass flow meters

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Installation requirements for mass flow meters 1.1 Selection of installation location (1) The installation location should be far away from any sources that could cause mechanical vibrations in the pipeline, such as pumps on the process pipelines. If sensors are used in series on the same pipeline, it is necessary to prevent interference caused by resonance; the distance between sensors should be at least three times the width of the sensor’s physical dimensions. (2) Attention should be paid to the installation location of sensors with regard to the expansion and deformation of the process pipeline due to temperature changes, and they must not be installed near the expansion joints of the process pipeline. If installed near an expansion joint, the expansion and contraction of the pipeline will generate lateral stresses, causing changes in the sensor’s zero point and affecting measurement accuracy. 　　(3) The installation location of the sensor should be far away from industrial electromagnetic interference sources such as high-power motors and transformers; otherwise, the self-oscillation of the measuring tube in the sensor will be disturbed, and the weak signals detected by the speed sensor may be drowned out by the noise caused by electromagnetic interference. Sensors should be placed at a distance of at least 5 meters away from transformers and motors. 　　4) The installation location of the mass flow meter when measuring liquids should be such that the sensor is positioned in a way that ensures the liquid fills the pipe, thereby reducing the impact of density changes on the accuracy of measurements. And when the process pipeline needs to be cleaned, the installation location should allow for complete drainage of the liquid. To prevent gas from accumulating inside the sensor, it should be avoided to install the sensor at the lowest point of the piping system. 　　(5) The installation location of the mass flow meter when measuring gases should avoid the lowest point of the pipeline, so as to prevent liquid from accumulating inside the sensor. 　　1.2 Selection of installation method The installation method for sensors is primarily determined by the phase of the fluid and the conditions of the process; there are three possible installation methods. 　　(1) If the fluid being measured is a liquid, it is generally advisable to install the sensor with its housing facing downward, in order to prevent air from accumulating inside the sensor’s vibration tube and thus ensure accurate measurement of the mass flow rate. (2) If the fluid being measured is a gas, it is usually better to install the sensor with its housing facing upward, so as to avoid the accumulation of condensation inside the sensor’s vibration tube. 　　(3) If the fluid under test is a mixed slurry of liquids and solids, the sensor should be installed in a vertical pipe; this prevents particles from accumulating inside the sensor’s Coriolis force measurement tube. Furthermore, if the process pipeline needs to be cleaned using gas and steam, this installation method also facilitates cleaning; however, it is more difficult to secure than the first two methods, and it results in higher pressure losses. 　　1.3 Flow direction of installation 　　Regardless of the flow direction, the flow sensor can accurately measure the flow rate. Arrows are generally used on sensors to indicate the normal flow direction of the fluid. 　　That’s all for today’s discussion on the installation location, method, and flow direction of mass flow meters. I hope this will be helpful for everyone when using this equipment in the future.