一、进口一体式涡街流量计概述

一体式涡街流量计具有良好的介质适应能力，无需温度压力补偿即可直接测量蒸汽、空气、气体、水、液体的工况体积的流量，配备温度、压力传感器可用于测量标况体积流量和质量流量。参数能长期稳定工作，采用压电应力式传感器可在-20℃～+250℃的工作温度范围内工作。有模拟标准信号，也有数字脉冲信号输出，可以与计算机等数字系统配套使用。

The integrated vortex flowmeter has good medium adaptability and can directly measure the volume flow of steam, air, gas, water, and liquid without temperature and pressure compensation. Equipped with temperature and pressure sensors, it can be used to measure standard volume flow and mass flow. The parameters can work stably for a long time, and the piezoelectric stress sensor can operate within the working temperature range of -20 ℃ to+250 ℃. There are analog standard signals and digital pulse signal outputs, which can be used in conjunction with digital systems such as computers.

二、进口一体式涡街流量计工作原理

一体式涡街流量计在测量管中垂直插入一个柱状物时，流体通过柱状物两侧就交替地产生有规则的旋涡，这种旋涡列被称为卡门涡街。卡门涡街的释放频率与流体速度及柱状物的宽度有关，可用下式表示：

f＝St・v/d

式中：f－卡门涡街的释放频率

St－系数（称为斯特罗哈数）

v－流速

d－柱状物的宽度

卡门涡街释放频率f和流速v成正比，因此通过测量卡门涡街释放频率就可算出瞬时流量。

斯特罗哈数是涡街流量计的重要系数。在曲数的St≈0.17的平直部分，旋涡的释放频率与流速成正比，所以检出频率f就可求得流速v，由v求出体积流量。

涡街流量传感器得旋涡释放频率是由旋涡交替地作用于检测传感器（探头）上地应力通过在它内部地压电元件来检出地。

三、进口一体式涡街流量计主要技术指标

四、进口一体式涡街流量计的特点

1、无可动部件，长期稳定，结构简单便于安装和维护。

2、传感器输出为脉冲频率，其频率与被测流体的实际流量成线性，零点无漂移，性能十分稳定，结构形式多样，有管道式、插入式流量传感器形式。

3、精确度较高，通长气体的测量精度为1.5%。

4、测量量程范围宽。

5、压损小，属于节能流量仪表。

6、安装方式灵活，根据现场工艺管道不同，可水平，垂直和不同角度倾斜安装。

7、本仪器可广泛用压缩空气、饱和及过热蒸汽、天然气及各种介质流量的计量涡街流量计分为夹持式和一体化法兰型。

1. No movable parts, long-term stability, simple structure, easy installation and maintenance.

2. The output of the sensor is a pulse frequency, which is linear with the actual flow rate of the measured fluid. The zero point has no drift, and the performance is very stable. There are various structural forms, including pipeline and plug-in flow sensors.

3. High accuracy, with a measurement accuracy of 1.5% for full length gas.

4. Wide measurement range.

5. Low pressure loss, belonging to energy-saving flow instruments.

6. The installation method is flexible, and can be installed horizontally, vertically, and at different angles according to the different process pipelines on site.

7. This instrument can be widely used for measuring the flow rate of compressed air, saturated and superheated steam, natural gas, and various media. Vortex flow meters are divided into clamp type and integrated flange type.

五、进口一体式涡街流量计选型要求

1、流量计的选型尽可能不要使用流量工作在下限极限值，故流量计的口径应尽可能小，以获得更大的流速和流量范围。

2、流量计应使用在介质工作压力和温度范围的技术参数内。不要刻意选用高压力等级和超高温度的仪表，应根据实际工作压力和温度选用仪表，后者价格要高些。

3、在爆炸危险场所，应选用防爆型流量计。

4、涡街流量计的下限流量取决于介质的工况密度和运动粘度，其上限流量一般不受介质压力和温度的影响，因此确定流量范围只要确定实际可用的下限流量即可。计算出下限流量后，查流量范围表即可确定相应口径。

1. The selection of flow meters should avoid using flow operating at the lower limit value as much as possible, so the diameter of the flow meter should be as small as possible to obtain a larger flow rate and flow range.

2. The flowmeter should be used within the technical parameters of the working pressure and temperature range of the medium. Do not deliberately choose instruments with high pressure levels and ultra-high temperatures. Instruments should be selected based on actual working pressure and temperature, with the latter being more expensive.

3. In explosive hazardous areas, explosion-proof flow meters should be selected.

4. The lower limit flow rate of a vortex flowmeter depends on the operating density and kinematic viscosity of the medium, and its upper limit flow rate is generally not affected by the pressure and temperature of the medium. Therefore, determining the flow range only requires determining the actual available lower limit flow rate. After calculating the lower limit flow rate, check the flow range table to determine the corresponding caliber.

六、进口一体式涡街流量计安装环境

1、尽可能避开强电设备、高频设备、强开关电源设备。仪表的供电电源尽可能与这些设备分离。

2、避开高温热源和辐射源的直接影响。若必须安装，须有隔热通风措施。

3、避开高湿环境和强腐蚀气体环境。若必须安装，须有通风措施。

4、涡街流量仪表应尽量避免安装在振动较强的管道上。若必须安装，须在其上下游2D处加设管道紧固装置，并加防振垫，加强抗振效果。

5、仪表很好安装在室内，安装在室外应注意防水，特别注意在电气接口处应将电缆线弯成U形，避免水顺着电缆线进入放大器壳内。

6、仪表安装点周围应该留有较充裕的空间，以便安装接线和定期维护。

1. Try to avoid strong electrical equipment, high-frequency equipment, and strong switching power supply equipment as much as possible. The power supply of the instrument should be separated from these devices as much as possible.

2. Avoid the direct impact of high-temperature heat sources and radiation sources. If installation is necessary, insulation and ventilation measures must be taken.

3. Avoid high humidity and strong corrosive gas environments. If installation is necessary, ventilation measures must be taken.

4. Vortex flow meters should be installed on pipelines with strong vibrations as much as possible. If installation is necessary, pipeline fastening devices must be installed at the 2D upstream and downstream, and anti vibration pads must be added to enhance the anti vibration effect.

5. The instrument is easy to install indoors, but when installed outdoors, attention should be paid to waterproofing. Special attention should be paid to bending the cable into a U-shaped shape at the electrical interface to prevent water from entering the amplifier housing along the cable.

6. There should be ample space around the instrument installation point for installation wiring and regular maintenance.