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The general rules for the installation, use, and storage of vortex flowmeters are a summary by Changhui Instruments regarding the application of these devices. These technical requirements apply to the installation and use of all vortex flowmeters and can serve as a model for vortex flowmeter installation techniques. http://yunrun.com.cn/upload/202010/02/202010021421258223.png Vortex flow meter yunrun.com.cn/product/175.html Preparations before installation Before installation, check whether the packaging of the vortex flow meter is intact, and ensure that the model and designation of the vortex flow meter match those of the instrument required. Selection of installation location: 1. Although vortex flowmeters are designed to operate under harsh conditions, in order to maintain their accuracy and stability over the long term, the following factors should be taken into account when selecting the installation location: ① Ambient temperature. Try to avoid installing vortex flowmeters in areas with high temperatures or large temperature fluctuations. When exposed to the thermal radiation from production equipment, insulation and ventilation measures must be taken. If the temperature of the transmitter housing exceeds 85°C, it will cause abnormal operation of the instrument. When local display is available, the ambient temperature must not exceed -20~+60°C to prevent abnormal display on the LCD or even permanent damage to it. ②Atmospheric conditions: Avoid installing the flow meter in environments with corrosive gases or prolonged humidity. If installation is necessary in such environments, it should be specified at the time of ordering. And ventilation measures must be provided. ③Mechanical vibration or shock: Although vibration-resistant vortex flowmeters have strong capabilities for suppressing vibration disturbances, they should still be installed in locations with minimal vibration or shock, to prevent the vibration levels from exceeding the limits that the vortex flowmeter can tolerate. Weaker vibration interference helps to achieve a lower measurement limit. ④Pay attention to the process pipelines and installation methods; the length of the straight sections before and after the flow meter should meet the \"minimum requirements for straight sections\", and the inner diameter of these straight sections must not be smaller than that of the flow meter ； During installation, the center of the flow meter must be aligned with the center of the pipe. Installation notes: Note: Be sure that the gaskets on both sides of the vortex flow meter do not protrude into the pipeline, to avoid unpredictable fluctuations and errors in the readings. http://yunrun.com.cn/upload/202010/02/202010021534110315.png 2. The connection bolts of the flange must be tightened. 3. The pipe joints must be leak-proof ； The applied pressure must not exceed the specified maximum operating pressure. 4. When the component is under compression, do not loosen the sealing fastening bolts of the flange. 5. To ensure the measurement accuracy of the vortex flow meter, it must be installed in a straight pipe section, with sufficient lengths of straight pipe upstream and downstream to create the flow field distribution required by the meter. When the total length of the straight pipe is insufficient, priority is given to the length of the upstream straight pipe section; for details, please refer to the figure below. A. Reducing sleeves: Changhui Instruments recommends the use of concentric reducing sleeves; it is sufficient to ensure that the total straight-line length of the upstream components, including the large pipe and the diameter-changing section, is greater than 5D for flange-type or clamp-type vortex flowmeters, and 7D for insert-type vortex flowmeters. http://yunrun.com.cn/upload/202010/02/202010021541295306.png http://yunrun.com.cn/upload/202010/02/202010021549583835.png Eccentric reducer installation is not recommended, as it imposes strict requirements regarding the length of straight sections: it is necessary to ensure that the smaller pipe after the diameter change has at least 20d worth of straight section for the installation of the vortex flow meter. http://yunrun.com.cn/upload/202010/02/202010021544303260.png http://yunrun.com.cn/upload/202010/02/202010021554233563.png Note: D is the inner diameter of the large pipe ； d is the inner diameter of the tube. For vortex flow meters installed with flanges or clamps, when such meters are placed downstream of a bend, it is necessary to ensure that there is a straight pipe section of at least 5D in length upstream of the vortex flow meter ； No need to consider the downstream side ； For plug-in vortex flowmeters: there should be a straight pipe section of at least 7D in length upstream ； There should be a straight pipe section of at least 3D downstream. http://yunrun.com.cn/upload/202010/02/202010021647509704.png http://yunrun.com.cn/upload/202010/02/202010021648460015.png C. Valve position and length of the straight pipe section: The non-streamlined flow-blocking elements upstream of the vortex flow meter create vortices and severe distortions in the flow field; a straight pipe section with a length of at least 30D, or a flow regulator, is required to restore the flow field conditions necessary for proper operation of the vortex flow meter. Common flow restrictors include orifice plates, thermal resistors, and thermocouples. The effects caused by pressure-taking devices of the insertion structure are similar to those of valves. However, a valve with a small opening installed upstream of the vortex flow meter helps to absorb the pulsations in the fluid flow. a. For vortex flowmeters with a diameter of DN80 and above, Changhui Instruments recommends installing them upstream of the control valve. The length of the straight pipe section upstream of the vortex flowmeter depends on the conditions of the upstream pipeline (such as reducers, bends, etc., as described above). The downstream part can be ignored. http://yunrun.com.cn/upload/202010/02/202010021657009891.png b. For vortex flowmeters with a diameter of DN80 or less, in order to reduce flow pulsations, Changhui Instruments recommends installing the vortex flowmeter downstream of the control valve, with a straight pipe section of at least 30D in length between them. http://yunrun.com.cn/upload/202010/02/202010021659408927.png D. Solutions for pulsating flow a. Effects of pulsating flow: Pulsating flow can occur in the gas pipelines used with piston or Roots-type blowers or air compressors, or in the high-pressure liquid pipelines used with piston or Roots-type pumps. To address this, a pulsation flow attenuator such as a rectifier or an expansion section (expander) can be installed upstream of the vortex flow meter. The valve can also be installed upstream of the vortex flow meter, but this requires a longer straight pipe section upstream. http://yunrun.com.cn/upload/202010/02/202010021709207134.png b. Piston or plunger pumps: An accumulator is installed upstream of the vortex flow meter, while a throttle plate or valve is placed downstream to reduce fluid vibration. http://yunrun.com.cn/upload/202010/02/202010021716175959.png 6. Vortex flow meters can be installed vertically, horizontally, or at any other angle. However, when measuring wet gases, condensable gases, high-temperature media, or liquids, it is necessary to determine an appropriate installation method based on the actual conditions, to ensure that the fluid within the pipe flows in a single phase and to avoid additional interference and excessive use. For details, please refer to Figure ① below: The installation location of the vortex flow meter for detecting the flow rate of gases at normal temperature and in dry conditions can be anywhere along the pipeline; it can be installed within a full 360° range. http://yunrun.com.cn/upload/202010/02/202010021820467220.png ② Installation of vortex flowmeters for measuring the flow rate of gases and humid gases at room temperature: Changhui Instruments recommends installing them in pipes that run vertically from the ground; they can also be installed in horizontal pipes at a higher elevation, in order to avoid interference from condensed liquids. http://yunrun.com.cn/upload/202010/02/202010021824510965.png ③ Installation of vortex flow meters for measuring the flow rate of high-temperature gases such as steam: Changhui Instruments recommends installing them in pipelines at ground level or in horizontal pipelines at a higher position. When installed in horizontal pipelines, the vortex flow meters should be placed at an angle of ±30° from the vertical direction, in order to reduce the high-temperature radiation from the pipeline on the electronic components. http://yunrun.com.cn/upload/202010/02/202010021828077092.png ④ Installation of vortex flow meters for measuring the flow rate of liquids at normal or low temperatures: Changhui Instruments recommends installing them in upward-flowing pipes; they can also be installed in horizontal pipes at lower positions, in order to ensure that the liquid level is full and to prevent two-phase flow from occurring. Installation is also allowed over a full 360° range. http://yunrun.com.cn/upload/202010/02/202010021847479969.png ⑤ Installation of vortex flowmeters for measuring the flow rate of high-temperature liquids: Changhui Instruments recommends installing them in upward-flowing pipes; they can also be installed in horizontal pipes at lower positions, to ensure that the liquid fills the pipe completely and to prevent two-phase flow from occurring. When installed in horizontal pipes, vortex flow meters must be mounted at an angle of ±30° relative to a vertically vertical direction, in order to reduce the high-temperature radiation from the pipes on the electronic circuits. http://yunrun.com.cn/upload/202010/02/202010022044338685.png 7. Although anti-vibration vortex flow meters have strong capabilities for suppressing vibration disturbances, they should still be installed in locations with minimal vibration or shock, to prevent the vibration levels from exceeding what the vortex flow meter can handle (vibration acceleration ≤ 20 m/s2, with continuous vibrations within the frequency range of 10 Hz–110 Hz). In situations where vibration is particularly severe, measures such as reinforcement or vibration reduction should be considered. http://yunrun.com.cn/upload/202010/02/202010021529494489.png 8. Pressure detection and temperature detection should be located downstream of the vortex flow meter. When pressure measurement is required, the pressure tap must be placed 2D-7D downstream of the vortex flow meter. When temperature measurement is required, place the temperature sensor between 1D and 2D downstream of the pressure measurement point; please refer to the diagram below for details. http://yunrun.com.cn/upload/202010/02/202010021448053861.png Installation steps: For the installation steps of the vortex flow meter, refer to the instrument’s installation diagram and dimensional drawings. 1. Cut out a section of pipe whose length is related to that of the vortex flowmeter itself; the required cutting length can be found in the instrument’s dimensional specifications and relevant flange standards. 2. Pipe cutting and fracture finishing: Remove burrs and grind to facilitate proper fitting and flange alignment. Note: Burrs, weld scars, slag, or protrusions from gaskets into the inner wall of the pipe directly result in the loss of straight pipe sections, and these must be eliminated. Otherwise, it will lead to unacceptable measurement errors. The smaller the flow meter diameter, the more pronounced the effect. 3. Careful adjustment should be made in the welded flange to ensure that the flange face is perpendicular to the axis of the process pipeline, and that the flange is concentric with the process pipeline. Note: Except for those vortex flowmeters whose bodies can be directly welded to the pipeline, it is absolutely forbidden to weld the flange connected to the vortex flowmeter directly to the process pipeline, as the high temperatures generated by continuous full welding will cause the piezoelectric crystals in the sensor to permanently lose their piezoelectric properties, rendering the sensor completely unusable! 4. Verify that the flow direction indicator of the vortex flow meter is consistent with the flow direction of the fluid. The flange, gasket, and flow meter are clamped together concentrically with bolts to form a single unit. 5. Tighten the nuts diagonally, and finally fasten them in sequence to ensure even stress distribution across all screws and parallel sealing surfaces, thus guaranteeing a reliable seal. 6. Complete the cable connection. Insulation: When insulating pipes that transport fluids at high or low temperatures, be careful not to use insulation material to cover the heat sinks of vortex flow meters. http://yunrun.com.cn/upload/202010/02/202010022057517007.png Cleaning pipes: For newly installed pipes or those that have been repaired, it is necessary to clean and purge them before putting them into use, in order to remove rust, scale, and sediment from within the pipes. During cleaning, the fluid should flow through the bypass pipe to avoid damaging the vortex flow meter. If there is no bypass pipe, a short section of pipe should be temporarily installed to replace the vortex flow meter. http://yunrun.com.cn/upload/202010/02/202010022059556359.png