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The spiral vortex flowmeter is a type of gas flowmeter. When the gas medium enters the inlet of the flow sensor, the spiral blades force the fluid to move in a rotational motion, thereby creating a vortex flow at the center of the vortex generator. This vortex flow moves forward through the Venturi tube; upon reaching the constricted section, it is suddenly throttled, which accelerates the vortex flow. Once the vortex flow enters the diffuser section, backflow forces it to undergo a second rotational movement in a spiral pattern. At this point, the rotation frequency of the vortex flow is proportional to the flow velocity of the medium, and it is linear. The weak charge signals detected by the two piezoelectric sensors of the helical vortex flowmeter are simultaneously amplified, filtered, and shaped by pre-amplifiers, resulting in two pulse signals whose frequencies are proportional to the flow velocity. The processing circuit in the flow integrator compares and analyzes the pulse signals from the two channels, eliminates interference signals, and counts the normal flow signals. An intelligent swirl vortex flowmeter is mainly composed of a vortex generator, housing, vortex detection components, a de-swirl rectifier, temperature interface, pressure interface, and signal output interface. I. Advantages of the swirl vortex flowmeter It achieves mechatronics, eliminating the need for manual supervision during routine measurement. During process installation, the upper and lower straight sections of the pipeline for the instrument can be **shorter** than those of a orifice plate flow meter. It has a wide flow measurement range, allowing it to operate effectively in low-flow areas where orifice plate flow meters cannot be used. The flow signal can be displayed locally or transmitted remotely as needed. There are no moving parts, so there is no mechanical wear of the instrument for routine measurements. II. Disadvantages of the swirl vortex flowmeter It is relatively sensitive to interference signals such as noise or vibration. If there is a strong magnetic field in the vicinity of the measuring instrument, or if there is significant noise or disturbance upstream of the instrument (such as howling sounds and other mechanical vibrations caused by throttling or changes in flow direction), then the operation of the instrument will be affected to some extent; there is no historical record of the measured parameters. Since flow measurement is an important basis for process control and cost assessment, it is sometimes necessary to conduct comparative analyses of measurement data from different periods in history. This requires access to historical records of pressure, temperature, and instantaneous (accumulated) flow rates. Therefore, without regular manual data collection or the development of secondary instruments, the required information cannot be obtained. The reliability and stability of these instruments still need to be tested under various complex operating conditions. Additionally, the sensitivity of the instruments’ measurement accuracy to flow patterns and medium contamination also requires further study. Such instruments can determine their starting flow rate autonomously by setting a cutoff frequency, based on the production conditions at the measurement site. However, if the cutoff frequency is set too high, the starting flow rate of the instrument increases, which may lead to undercounting of flow volume. If the cutoff frequency is set too low, the sensitivity of the instrument increases, and minor external vibrations or stray signals may cause the instrument to activate even when no fluid is passing through, resulting in overcounting of flow volume. III. Precautions during use When installed outdoors, the flow meter should be covered at the top to prevent rainwater from entering and direct sunlight from damaging it, thus ensuring its long service life. In winter, it is necessary to insulate the flow meter housing to prevent liquid accumulation from freezing and causing damage to the flow meter. The area around the flow meter must be free from strong external magnetic field interference and intense mechanical vibrations. It should be kept away from elements that can disrupt the flow pattern (such as compressors, pressure regulators, tees, elbows, etc.), the straight sections before and after the instrument must be concentric, its inner walls must be smooth and straight, and the fluid being measured must be a clean, single-phase fluid. The flow meter should be reliably grounded, but it must not share the ground wire with high-voltage electrical systems. Before installing the flow meter, the pipes should be cleaned of debris such as fragments, slag, stones, dust, etc. When putting the flow meter into operation, the valve should be opened or closed slowly to prevent damage to the pipelines and instruments caused by sudden air currents. Instruments should be calibrated regularly to ensure their accuracy and reliability over the long term (to avoid unexpected shutdowns and data loss). For vortex flowmeters of the same specification, their core components such as the vortex generator and guide vane cannot be interchanged; otherwise, it is necessary to recalibrate the meter’s coefficient of measurement and perform systematic adjustments to the temperature and pressure sensors attached to it.