What is a steam flow meter?
This article describes in detail what is a steam flowmeter, as well as the classification of the steam flowmeter; if you feel that the answer is helpful to you, please raise your hand, give the U.S. Weidun VTON flowmeter point a praise!
Steam flowmeter is a flowmeter that can measure the flow of steam. Steam flowmeter classification are: steam vortex flowmeter, orifice plate flowmeter, elbow, Williba, float type and rotary wing flow and so on.
If the frequency of use in accordance with the VTON is commonly used steam flowmeter is divided into two kinds:
One, vortex flowmeter (usually called steam vortex flowmeter)
1, the site has a vibration will affect the accuracy of the flowmeter, vortex and other mechanical vibration-sensitive flowmeter, in the process of installation, in addition to try to meet the front and rear of the straight pipe section, etc., should also pay attention to the flowmeter before and after piping for reliable support. Flow meter before and after the pipeline for reliable support design. External vibration will make the vortex flowmeter measurement error, or even can not work properly. If pipeline vibration is unavoidable, should be used to anti-interference ability of the differential pressure flowmeter.
2, temperature sensor quality, or damage will affect the accuracy of the flow meter.
Pressure sensor quality or damage will affect the accuracy of the flow meter.
1) zero drift. Differential pressure transmitter installed to the site when put into use, often found that the zero position and factory calibration of the zero position is not consistent. This zero output deviation is called static pressure error. Adjustment method is to the positive and negative pressure chamber into the same static pressure, the three-valve high and low pressure valves in one open, the other closed, the balance valve open, if you suspect that the positive and negative pressure chamber is not yet full of the measured medium, the positive and negative pressure chamber through the pressure relief valve on the exhaust of the accumulated gas or liquid, and then check the output of the transmitter.
2)Pressure-relief pipe arrangement is unreasonable. Pilot line should ensure that a reasonable slope so that the pipe may appear in the bubble faster to the mother tube, the pipe impurities such as faster sink to the drain valve. The pilot line should be regularly inspected and maintained to ensure that there is no leakage or blockage. The inner diameter of the pilot pipe is related to the nature of the fluid being measured and the total length of the pilot pipe. For steam systems, the inner diameter of the pilot pipe is generally about 10mm. In order to avoid inconsistent temperature of the medium in the positive and negative pressure pipes, resulting in differences in density and transmission distortion, the positive and negative pressure pipes should be arranged as close as possible. When used in outdoor or cold areas, the liquid in the pilot tube may freeze, so need to accompany the heat insulation, but should avoid accompanying the heat pipe directly around the pilot tube, resulting in partial vaporization of the medium, false error.
3, flowmeter probe installation method, probe quality is also an important factor affecting the accuracy of the flowmeter.
4, steam flow rate changes
In order to ensure that the flow rate information can be accurately expressed in the whole range of conditions or demand for steam flow, steam flowmeter must be able to measure from the extreme low load to the zui big load of the whole range, that is, the steam flowmeter should have a sufficiently large range ratio. However, care must be taken when it comes to range ratios because they are based on actual flow rates. Steam systems generally have a maximum allowable flow rate of 35 m/s, and higher flow rates can cause erosion and noise in the system. And different flow meters allow zui low flow rate is different, for example, general vortex flowmeter, can measure the zui low steam flow rate of 2.8 m / s. Therefore, for the flow rate changes in the system, it is very easy to cause in the low flow rate when some flowmeter can not be accurately measured or can not measure the fact.
5, field installation methods: a, straight pipe section required before ten after five, b, before and after the end to keep free of obstacles and leaks.
Two, orifice plate flowmeter
1. Vortex flowmeter to achieve excellent metering effect of the range ratio is 1:10, that is, the minimum flow rate: the maximum flow rate
2. Temperature sensor quality, or damage will affect the accuracy of the flowmeter.
3. Pressure sensor quality or damage will affect the accuracy of the flow meter.
4. On-site installation methods: a. Straight pipe section requires the front ten and five, b. Front and rear ends to remain free of obstacles and leaks, and so on