Proteus Industries Inc. – Liquid Flow Meters

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Proteus Industries Inc. – Liquid Flow Meters A liquid flow meter is a device, which is utilized to calculate linear, non-liner, mass or volumetric flow rate of a liquid. Liquid flow measurement is the procedure of calculating liquid stream in an industrial plant. A liquid flow can be calculated through a range of various different liquid flow meters such ultrasonic, magnetic, vortex mass flow meter, differential pressure, Coriolis, turbine and positive displacement meters. A positive displacement meter calculates the liquid flow by collecting a fixed amount of fluid and then the flow of liquid is gauged by the number of times the chamber is filled and emptied. Further flow measurement techniques are based on forces created by the flowing streams as it overpowers an identified compression to gauge the flow indirectly. A liquid flow can also be calculated by determining the speed of the liquid stream over an identified area. For comparatively large sized liquid streams, tracer method can be utilized to evaluate the rate of flow from the change in concentration of a radioactive isotope or a dye.

When it comes to select a liquid flow meter for a specific plant or industrial setting, it is also imperative to consider some intangible factors such as familiarity of personnel working at the plant and their knowhow with the maintenance and calibration, availability of the spare parts and the average duration between two events of failure. Among a few most common mistakes in liquid flow measurement is that instead of opting for a device that may function accurately, an effort is made to validate the use of a device for the reason of it being low in cost, however, such low cost strategies can turn out to be costliest mistakes when it comes to installations. In such applications where products are purchased and sold based on the reading of the liquid flow meter, it is critical to have the liquid flow meter in place with absolute accuracy. On the other hand, in certain settings repeatability can be more significant than complete precision. That is why it is recommended to individually establish the requirement for precision and repeatability for every application and to state both in the specifications. In case satisfactory metering performance is obtained from the liquid flow meters of two different categories where one has moving parts, and another has no moving parts then it is suggested to select the one, which does not have moving parts because they are considered as a possible cause of complications. Not simply because of apparent wear, sensitivity to coating and lubrication but also for the reason that moving parts demand clearance tolerances, which may at times lead to a failure in meeting the standard when it comes to calculation of flow. Even with highly maintained and standardized


flow meters, this uncalculated stream differs with variations in viscosity and temperature of the fluid. Variation in temperature also alters the dimension within the liquid flow meter and demands for reparation. On the other hand, if the similar performance is obtained from a single point sensor and full flow meter both, then it is mostly recommended to go for the latter one because the former one does not consider the full flow. They calculate when deployed to a depth where the speed of the flow is the average of the velocity profile throughout the pipe. Additionally, even if this point is determined carefully during the calibration, it is still not guaranteed that it will stay unchanged because the velocity profile varies with the temperature, viscosity, flow rate and several other factors. Prior to specifying a liquid flow meter, it is also suggested to analyze if the flow information is going to be more useful when displayed in mass or volumetric units. When it comes to measuring the flow of compressible materials, volumetric flow is not that useful until density and viscosity is constant. When the volumetric flow of incompressible fluids is calculated, the existence of suspended bubbles will cause error.

Even though in ideal circumstances, the flow meter should not be impacted by its environmental factors, in reality, this not the case. Most of the times, error in the calculation occurs because of incorrect installation of the liquid flow meter or the environment related factors. Information can be collected without any impact of external environmental factors when the liquid flow meter is calibrated in the specified flow conditions. The outcome of a liquid flow meter calibration will lead towards two associated indicators, which are a performance indicator metric and a flow rate metric. It must be kept in mind that in regard to these considerations, mass flow meters are not sensitive to variations in viscosity, pressure, and density and are not influenced by variations in the Reynolds number. In addition to that, various flumes that are underutilized in chemical industry can calculate flow in partially full pipes and can let through large settleable or floating solids.


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