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For new flow meters with orifice plates, or those that have been taken out of service for a period of time and then restarted, it is necessary to check the pressure guiding pipelines for any blockages or leaks before putting them into use. For liquid media, the pressure guiding pipelines should be filled with clean water or some other fluid suitable for transmitting pressure; attention should also be paid to removing any gas that may have entered the pipelines. For gas media, care must be taken to eliminate any liquid that has accumulated in the pipelines. (1) Before commissioning, open the balance valve in the \"three-valve assembly\", close tightly the valves on the positive and negative pressure sampling pipelines, and check and adjust the zero point of the differential pressure transmitter. Be sure to note that the \"zero point\" is determined when the pressure in the positive and negative pressure chambers is exactly equal (i.e., the differential pressure is 0); verify and adjust the differential pressure transmitter under these conditions. (2) Even with the \"balance valve\" fully opened under fluid flow conditions, the zero point cannot be checked unless the pressure-taking valves on the positive and negative pressure-taking pipelines are tightly closed. Because the balance valve itself has resistance, it cannot fully balance the pressures in the positive and negative pressure chambers; thus, a \"zero differential pressure\" state cannot be achieved. (3) When measuring the flow rate of dirty fluids, a settler or isolator must be installed. Pay attention to how to reasonably select the locations of the inlet, outlet, and drain port for the pressure-guiding fluid in order to achieve waste discharge. (4) When measuring the flow rate of corrosive fluids, it is essential to choose an appropriate isolator, select a suitable isolation fluid based on the specific gravity of the medium, and pay attention to properly selecting the location where the isolation fluid meets the fluid being measured. (5) Whether the design parameters of the orifice plate flow meter match the actual parameters is directly related to the measurement accuracy. When a orifice plate flow meter is put into use, if the measured parameters fall within the range of the design parameters, the measurement accuracy generally does not exceed the accuracy specified in the design calculations ； However, if the measured parameters are far from the range of the design parameters (assuming that the selection, manufacturing, and installation of the standard orifice plate and differential pressure transmitter are all proper), it is possible that the provided design parameters are incorrect; in such cases, the design parameters should be altered, and the standard orifice plate should be redesigned and recalculated. For more information, please visit the company’s official website at http://www.yb1518.com/. Please retain this link when reproducing the content! http://www.yb1518.com/UploadFiles/2012118173632146.jpg