College】 【weak vortex flowmeter in use Common Problems and Solutions --- Power By 【China】 weak home network.

<br> vortex flowmeter is mainly used for industrial pipe medium fluid flow measurement, such as gas, liquid, vapor and other media. .Pressure loss is characterized by small, measuring range, high precision in the measurement conditions are not nearly the volume density of the fluid flow, pressure, temperature, viscosity and other parameters. .No moving mechanical parts, so high reliability and little maintenance. .Long-term stability of the instrument parameters. .This instrument uses piezoelectric stress sensors, high reliability, can be -20 ℃ ~ +250 ℃ operating temperature range. .With analog standard signal, but also digital pulse signal output, easily supporting the use of computers and other digital systems is a more advanced and ideal flow meter. .<BR> <BR> <BR> <BR> Major problems are: ① indicates the long-term are not allowed; ② has never been instructed; ③ indicate large-scale fluctuations, can not read; ④ instructed to not return to zero; ⑤ no small flow .instructions; ⑧ instructions can also be a large flow and small flow direction are not allowed; ⑦ changes indicate changes in flow can not keep up; ⑧ meter K factor can not be determined, many data are inconsistent. .<BR> <BR> Analysis and solution of major issues <BR> <BR> analysis and solution of these problems take Suke Instrument Co., Ltd, Jiangsu Province, the Ministry of all the comrades of the past six months, since the issue complicated, juice from the design installation, .parameter tuning, routine maintenance, operating environment, there are varying degrees of problems, many issues are entwined, and some problems running the process to wait a certain time, so the solution to the problems brought great difficulties. .Some of the problems common for several reasons by different causes, some of the reasons are different on several issues. .<BR> <BR> Summarize the main cause of these problems, mainly related to the following areas: <BR> <BR> 1, selection issues. .Some selection of vortex sensor in diameter or in the design and selection of process conditions, after the change, make a big choice - a specification, the actual selection of the diameter should be chosen as small as possible in order to improve the measurement accuracy, the main reasons in this regard with .problem ①, ③, ⑥ related. .For example, a vortex line to use several devices designed for reference, sometimes due to process some of the equipment is not used, resulting in the actual use of the current flow decreases, causing the original design and selection of the actual use of large diameter, equivalent to improve the flow can be measured .lower limit, process piping can not guarantee a small flow direction, flow rate, can have use, because sometimes too difficult to reinvent. .Changes in process conditions is only temporary. .Parameters can be combined with the re-tuning to improve the accuracy of instructions. .<BR> <BR> 2, installation problems. .The main straight in front of the sensor length is not enough, affect the measurement accuracy, the main reasons this problem ① the same. .For example: The sensor in front of straight pipe is obviously inadequate, since FIC203 not used for measurement, only for the control, so you can use the equivalent of the accuracy of the current downgrade. .<BR> <BR> 3, the reasons for the direction of parameter tuning. .For that parameter, resulting in the wrong direction instrument. .Parameter error makes the secondary instrument full-scale frequency calculation error, the main reasons for this same problem ①, ③ related. .Almost the same degree of frequency over the long term are not allowed to make the instructions, the actual frequency of big full-scale computing makes full-scale frequency fluctuations in a wide range of directions, not reading, and data on the inconsistency of the parameters will affect the final determination of the parameters, and ultimately through the .re-determine the calibration parameters compared with each other to solve this problem. .<BR> <BR> 4, secondary instrument failure. .This part of the fault more, including: an instrument circuit board has broken place, individual bit display range setting bad, K factor setting individual bits show the bad, making it impossible to determine the range of settings, and set the K factor, which .The main reason to question some of ①, ② related. .By the corresponding fault repair, the problem is resolved. .<BR> <BR> 5, four-line connection problems. .Part of the circuit surface, good connections, double check, and some loose joints caused by the actual circuit has been interrupted, although the connection is tight and some joint Vice-line issue However, screws are tightened in the line of the skin, but also makes circuit .interruption, this is partly because the main problem ② the same. .The corresponding line problem solving, problems resolved accordingly. .<BR> <BR> 6, secondary instrument and meter follow-up to the connection problem. .As follow-up questions or because of instrument maintenance follow-up instrument, making the secondary instrument mA output loop interrupted, for this type of secondary instrument, this part of the main reasons related to the same problem ②. . Especially for follow-up of the recorder, the recorder can not fix long-term damage to the case, we must pay attention to short the output of the second instrument. .<BR> <BR> 7, the secondary instrument cable fault caused the horizontal axis loop has no instructions. .Due to the long run, coupled by the dust, creating a horizontal axis cable fault, clean or replace the horizontal axis through the wires, the problem is resolved. .<BR> <BR> 8, the problem was mainly due to the secondary instrument ⑦ indicator head coil fixed screw worked loose, causing subsidence header, pointer and the case friction, action not working, by adjusting the meter and re-fixed, .solve the problem accordingly. .<BR> <BR> 9, use of environmental problems. .Particular sensor installed in the ground part of the well, due to environmental humidity, resulting in circuit board damp, this part of the main reasons for the same problem ②, ② related. .Technical innovation through appropriate measures on the part of environmental humidity sensor re-made part of the probe separation and conversion of part of the deal, use a separate sensor, Gushan the working environment, has this part of the instrument to work well. .<BR> <BR> 10, the on-site calibration is not good, or because the adjustment of the actual situation after the re-change. .As on-site noise and vibration and sensitivity adjustment balance adjustment is not good. .Or because after running for some time to adjust the scene after the situation changes again, resulting in direct questions, this part of the main reasons for the same problem ④, ⑤ related. .Using the oscilloscope, together with process operation, re-adjustment. .<BR> <BR> 11, ⑧ The reason for the problem separately, based on the impact of this problem for a long time to analyze and solve the problem, because the East does not have the K factor calibration of chemical conditions, K factor can only be provided by the manufacturer based .information, manufacturers own some of the changes, resulting in several information provided on the K factor is not - To affect the problem-solving. .Re-calibration by finding the conditions, or changes through repeated comparison, they finally established a unified instrument parameters. .<BR> <BR> Through a period of careful analysis summary, the vortex can be basically solved the problems, now this part of the instrument is running well, basically to meet the needs of factory production process. .<BR> <BR> Summary <BR> <BR> 1, the K coefficient of the vortex street in a very importantpart of playing the whole, K factor directly affects the accuracy or the accuracy of loops, instrument replacement parts, and .wear process piping, etc., may affect the K factor. .The Dongfang Chemical Plant and lack the means and capacity calibration, calibration can only be sent by the impact of process operation, removed from the vortex tube sent to the calibration time of 5,6 days, technology is difficult to meet, which can not be determined .K factor. .This year, through the transformation between the flow meter, although already has a smaller diameter vortex calibration conditions, but for larger diameter vortex is still powerless, after the vortex should be taken in the field calibration method, using standard frequency and portable ultrasound .flow meter, measure the instantaneous flow pipe and sensor pulse output frequency, on-site computing K factor. .<BR> <BR> 2, should be cleaned regularly vortex flowmeter probe, the inspection had found that the detection of individual probe holes have been blocked dirt, and even wrapped in plastic sheeting, affecting the normal measurements. .<BR> <BR> 3, grounding and shielding conditions regularly checked to eliminate outside interference. .Sometimes the problem is due to direct interference in electronics distribution. .<BR> <BR> 4, the installation environment humidity probe. .Drying time should be on a regular basis, or for moisture treatment. .Since the end of the probe itself as a moisture treatment, wet after the impact of running. .<BR> <BR> 5, meter data management should be taken seriously enough, in order to facilitate future work. .<BR> <BR>.