Vortex flowmeter temperature and pressure compensation one flange type intelligent meter head

Overview.

LUGB series vortex flow meter, is a velocity flow meter, mainly used for industrial pipeline fluid medium flow measurement, such as gas, liquid, steam and a variety of media measurement.

It is characterized by small pressure loss, a large range, high accuracy, in measuring the volume flow of working conditions almost independent of fluid density, pressure, temperature, viscosity and other parameters. No movable mechanical parts, so high reliability, low maintenance, instrument constants can be long-term stability. Among them, the insertion type vortex flowmeter, in the large pipeline welded base, and with the installation of ball valves, can be loaded and unloaded in a constant flow, so as to facilitate operation in dirty media and regular cleaning and maintenance.

The meter adopts piezoelectric stress sensor, can be used for a long time in the working temperature range of -20 ℃ to +300 ℃, widely used in petroleum, chemical, metallurgical, pharmaceutical, water treatment and other industries in the field of flow measurement and measurement and control work. The output of this instrument, with analog standard signal, also has a digital pulse signal output, easy to use with computers and other digital systems, is a more advanced, ideal flow meter.

◆Product implementation standard: JB/T9249-2015 (industry standard)

◆General flange standard: GB/T9119-2010 (national standard)

◆Type approval certificate: 2010F450-33 2006F414-33

Working principle.

When a columnar resistance body is inserted vertically in the fluid, vortices will be generated alternately on both sides of it, with the fluid moving in the downstream direction, called Carman vortex street, see the figure below. The resistance body that generates the vortex street is called the vortex generator. Experimentally, it is proved that the frequency of vortex is proportional to the flow velocity, which can be expressed by the following equation：

Experimentally proven: when the distance h between two columns of vortices and the distance L between two vortices in the same column meet the formula h/L = 0.281, the asymmetric vortex column can maintain a stable state. When the fluid Reynolds number Re in the range of 5000-150000, Sr is basically unchanged, so when the vortex generator column width d and Strohal number Sr for a fixed value of the vortex generator frequency transmission fluid is proportional to the average flow rate, that is, proportional to the flow Q and pressure, temperature, density and other parameters are not relevant.

When the vortex is generated on both sides of the column, the sensor is subject to the effect of alternating lift force perpendicular to the direction of flow induction signal, the frequency of change of the lift force is the vortex frequency, the sensor will send the signal to the converter to amplify and shape the pulse signal with the flow rate is linearly proportional to the direct output or will be converted into a 4 ~ 20mA standard signal output, the relationship between flow Q and frequency is as follows：

可以测量瞬间量(气)和记录应用的水的总量(Qa)。气率水被泵,如20加仑每分钟,每分钟550加仑,等等。总数量将随着时间的推移被记录为加仑,数万加仑,数百加仑或千余加仑。累积应用加仑是规范米。假如记录必须Qa在平方英尺-英寸,客户务必顺序规定。针对大部分应用在农业、记录Qa在平方英尺-英寸好的。假如累积Qa平方英尺-英寸不能用,随后顺序千余加仑计记录,或1万加仑,假如可能的话。一旦安装完毕,保证电磁流量计厂商解释如何高效阅读仪表和记录读值。

管的尺寸是非常重要的。一些系统管道安装在管道的直径比为必要的。在那些情况下,它不大可能,一米的合理的成本系统将是可用的。建议是小直径管在小直径部分系统和安装一个优质涡街流量计,测量小流量。