Introduction to the classification of orifice plate flowmeters

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　　Orifice plate flow meters are widely used in many industries. There are two most common types of orifice plate flowmeters that can meet their requirements, namely integrated orifice plate flowmeters and intelligent orifice plate flowmeters. Next, our factory’s technical specialist will explain the differences between the two as follows: 1. The integrated orifice flow meter is a differential pressure generation device used for measuring flow rates; it can be used in conjunction with various differential pressure gauges or transmitters to measure the flow of various fluids in pipelines. The throttling components of an orifice flow meter include ring chamber orifices, nozzles, etc. 　　2. The intelligent orifice plate flow meter is a next-generation flow meter that integrates functions for measuring flow rate, temperature, and pressure, and it can also perform automatic compensation for temperature and pressure. Utilizing advanced microcomputer technology and low-power consumption techniques, this flow meter features strong functionality, a compact design, simple operation, and ease of use. 　　Conditions for pipeline installation: (1) The straight sections before and after the throttling element must be straight, with no visible bends. 　　(2) The straight pipe section used for installing the throttle element should be smooth; if it is not smooth, the flow coefficient should be multiplied by a roughness correction factor. 　　(3) To ensure that a fully developed turbulent velocity distribution is formed 1D in front of the throttling element, and to make this distribution uniformly axially symmetric, it is necessary that: 1) the straight pipe section be circular, and within a range of 2D in front of the throttling element, high precision is required regarding its circularity, with specific circularity criteria to be met. Specific measurement method: At the four vertical pipe sections of OD, D/2, D, and 2D in section (A), measure at least four individual inner diameter values of the pipes at roughly equal angular intervals each, and take the average as D. The difference between any single inner diameter measurement and the average value shall not exceed ±0.3%. 　　(B) Behind the throttle element, 8 individual inner diameter measurements were taken at the OD and 2D positions using the aforementioned method; the maximum deviation of any individual measurement from D shall not exceed ±2%. 　　2) A sufficiently long straight pipe section is required before and after the throttling element; the length of this straight pipe section depends on the type of local resistance element prior to the throttling element as well as on the diameter ratio β. 　　(4) The length of the straight pipe section between the first resistance element and the second resistance element on the upstream side of the throttle element can be taken as 1/2 of the values listed, depending on the form of the second resistance element and with β=0.7 (regardless of the actual value of β). 　　(5) When the area upstream of the throttle element is an open space or a large container with a diameter of ≥2D, the length of the straight pipe between the open space or large container and the throttle element must not be less than 30D (15D). The total length of the straight pipe section between the open space and the throttle element must also be no less than 30D (15D). 　　As a highly precise instrument, a flow meter requires strict adherence to its specifications not only during manufacturing and use, but also requires special attention during maintenance in order to prevent it from reaching the end of its useful life prematurely.