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How To Accurately Measure The Steam And Vortex Flowmeter Conservation

Mar 20, 2017

Steam flowmeter As a frequently used measuring instrument in industrial measurement, the frequency of use is very high. How to correctly measure it, the following talk about a talk.
First, the density of steam compensation to be scientific and accurate
In  order to properly measure the mass flow of steam, the steam pressure  and the temperature must be taken into account, and the steam density  should be compensated by the flow totalizer. The  platinum resistance of the steam temperature must be installed. The  platinum thermal resistance is inserted into the center of the pipeline.  The platinum thermal resistance is installed at 5 times downstream of  the flowmeter. The location of the pipe where the platinum thermal  resistance is installed adopts the insulation measures. The temperature value is accurate. It  is important to note that in the measurement of vapor pressure, it is  necessary to carry out zero migration if the pressure is applied with a  pressurized tube (since the gravity of the condensate in the pressurized  tube causes a certain amount of pressure between the pressure measured  by the pressure transmitter and the actual pressure Difference, resulting in density compensation error), can also be corrected in the flow totalizer. Pressure  transmitter installed in the steam flowmeter downstream of the 4 times  the diameter, the pressure transmitter before the valve, the gasket  should be smooth, to ensure accurate measurement of steam pressure. If you use the set pressure, temperature compensation, the value  should be set to close to the actual value, otherwise the error is very  large, generally not recommended.
In  the flow totalizer to correctly set the steam flow meter operating  status, which is the correct calculation of steam costs is essential. For the use of the steam state is not clear to determine the occasion,  it is recommended to use intelligent flow totalizer, with platinum  resistance, pressure transmitter temperature and pressure compensation,  so that the measured mass flow of steam the most accurate.
Second, the presence of vibration and electromagnetic interference should be avoided
The  maximum number of vortex flowmeter used in steam metering is affected  by the design principle, sensitive to mechanical vibration, the  measurement results are susceptible to vibration interference, and the  steam flowmeter should be used as a reliable support design, and  vibration buffering components such as pipe vibration Inevitably,  should use anti-interference ability relatively strong steam flow meter  (such as gas ultrasonic flowmeter, intelligent vortex flowmeter,  differential pressure flowmeter, etc.). If  the steam flowmeter on-site vibration interference, will be used in the  vortex steam flow meter to produce low-frequency pulse signal, the  steam flow meter will be the flow of these signals as a flow signal to  the flow totalizer, the cumulative flow, Resulting  in some vortex steam flowmeter in a period of time without steam in the  case there will be a certain amount of numerical accumulation. This is the "no steam and flow meter to take the word" reasons, so the  steam users in the absence of steam, but also with the steam unit to  share the table together to prevent the steam flow meter "air run."
Third, the steam flow meter range to be reasonable
The  range ratio is the ratio of the maximum flow rate and the minimum flow  rate that a flow meter can measure within a given range of accuracy. The  user according to their actual use of the choice of flow meter,  theoretically the steam flow meter to be selected range to fully cover  the user's range. Above the upper and lower flow rates will result in a serious risk of steam flowmeters. For  example: the actual average flow of 5t / h vortex steam flowmeter,  generally should choose a diameter of 150mm vortex flowmeter, but when  the flow down to 0.3t / h or more than 15t / h, the flowmeter will be  serious Metering inaccurate.
Fourth, the steam flow meter upstream and downstream straight pipe of the correct installation
For  the traditional vortex flowmeter, before and after the installation of  straight pipe requirements are 20 times the diameter and 5 times the  diameter (which is the front of the flow meter without obstacles and  other technical requirements; obstacles but also increase the straight  pipe, See the manufacturer's instructions). If  the upstream and downstream straight pipe is not enough, it will lead  to pipeline steam flow is not fully developed in the flow velocity  distribution profile distortion. The  user can adjust the flow rate distribution of the pipe by installing  the flow regulator or adding straight pipe before the steam flow meter  so that the fluid at the steam flow meter is fully developed. For some large diameter steam flow meter, to meet the upstream and  downstream straight pipe installation requirements are more important.

In modern industry, intelligent vortex flowmeter is used to measure steam medium. So how to better use in the protection of vortex flowmeter to make it a longer life? Talking  about the vortex flowmeter, I believe we are not unfamiliar, vortex  flowmeter as a commonly used industrial measurement of measuring  instruments, the frequency is very high. In  today's rapid industrial development, vortex flowmeter as a commonly  used measurement instrument in industrial measurement, in the case of  long and high frequency use, the use of vortex flowmeter internal  measurement components for its loss of life Have a certain impact. How to reduce the damage to the instrument?
1,  the vortex flowmeter due to the great distance in the vortex is  determined by the K-factor, the accuracy of the K-factor directly  affects the accuracy of the loop, the replacement of the instrument  parts wear and the process piping can affect the coefficient. Many chemical plant means and the lack of calibration, only through  the calibration, the impact of the operation process, will be sent to  the vortex of better respect for time.
2, vortex flowmeter regular inspection and shielding, eliminating the  interference of the outside, sometimes the problem due to interference.
3, vortex flowmeter should be discussed regularly cleaning, found to  check, individual probe detection hole was dirt or even wrapped in  plastic, affecting the normal measurement.
4, vortex flowmeter installation of the probe in a humid environment, should be dry or curing time. Because the detector itself to do moisture treatment, after the operation of the damp.
5, vortex flow meter data management should cause enough attention to the vortex flowmeter to facilitate future work.