是专门测量气体的一种常用流量计，东祥仪表研发生产涡街流量计有蒸汽涡街流量计、法兰安装、插入式、一体式、带温压补偿式等，应用非常广泛。 Vortex flowmeter is a commonly used flowmeter for measuring gas. Dongxiang Instrument developed and produced vortex flowmeters including steam vortex flowmeters, flange installation, plug-in type, integrated type, and temperature and pressure compensation type. widely. In normal times, we have explained how to choose a vortex flowmeter, but we have not separately talked about how to properly select the appropriate flange diameter of the vortex flowmeter. Below, the technical staff of Jiangsu Dongxiang Instrument will answer the questions for users. 1. Considering the maximum pressure loss of the vortex flowmeter, for liquids, the pressure loss generated by the vortex flowmeter at the maximum flow rate (that is, the maximum flow rate) should also be calculated to ensure that no cavitation will occur at the minimum working pressure. . 2. In order to ensure the measurement accuracy of the vortex flowmeter, the vortex flowmeter should be operated in a linear region under the premise of meeting the measurement range, that is, the minimum Reynolds number is not lower than the lower limit Reynolds number; Considering the sensitivity of the detection element, the nominal diameter of the vortex flowmeter is selected according to the minimum flow rate (minimum flow rate) of the vortex flowmeter in the instruction manual, that is, the lower limit of the flow of the vortex flowmeter should be less than the minimum flow rate of the actual working condition. ; Economics proposes the concept of the market from the perspective of reminding the nature of the economy. Economists think that the market is a range of commodity economy. Under the premise of a market economy, the so-called market refers to the sum of commodity exchange relations. The four basic elements of the exchange relationship that constitutes the city include: goods, buyers, sellers, rules and regulations, and prerequisites. Commodities refer to products or services used for communication; buyers refer to entities that have certain needs or desires and purchasing ability; sellers refer to entities that can supply products or services that meet the needs of consumers; rules and prerequisites for buying and selling are: Refers to the price, time, space, information and service methods on both sides. If according to the above three points, you can choose the appropriate flange diameter of the vortex flowmeter, and these three points have their own emphasis and basis, according to the first two points to consider the calculation of the selected diameter and the third point to consider the calculation There may be contradictions in the diameter, such as high flow velocity and large pressure loss. If you encounter this situation, you need to make a compromise according to the specific situation. The American Marketing Association refers to the market sales community as: after the planning and implementation of goods, labor services and strategies, pricing, distribution, promotion and other aspects, to complete the short-term communication process between individuals and organizations. In addition, in order to make the instrument work stably, when determining the diameter of the vortex flowmeter, the common flow rate should be more than 30% of its measurable flow range, and it is best to make the common flow rate within 30% to 70% of the vortex flowmeter range Within range
在测焦炉煤气不稳定时，输出信号不稳定，原因有以下几点： 1、涡街流量计不适宜安装在强振动的场合是应用者广为熟知的，但在磁场频繁变化的场合，涡街流量传感器会测出高于正常值的信号输出。 When the coke oven gas is unstable, the output signal of the vortex flowmeter is unstable. The reasons are as follows: 1. The vortex flowmeter is not suitable for installation in places with strong vibration. It is widely known by users, but it is frequently used in magnetic fields. When changing, the vortex flow sensor will detect a signal output higher than normal. Practice has proved that in a scene where no gas flows, when the vortex flow sensor is in a changing magnetic field, the vortex flow sensor will sense an error signal and output it when the magnetic field changes. When the change is over, the meter is in a stable magnetic field. The meter will output a normal signal. 2. Due to the high temperature and high humidity of the coke oven gas when it leaves the factory, there will be moisture in the gas transportation process. The gas flow drives the water back and forth to form a pulsating flow. When the vortex flow sensor is in this fluid state, the output data is suddenly large or small, and it cannot reflect the production status at all. 3. The crimping wire is not solid during the instrument wiring process, which causes the signal to be intermittent during transmission. 4. The ground wire of the instrument does not meet the requirements of the specification, so that 50Hz interference in strong electricity enters. When the normal signal is higher than 50Hz, a normal signal is output, otherwise an error signal is output. 5. Because the coke oven gas has many impurities, it is easy to crystallize, and the impurities are condensed on the sensor head, which causes measurement inaccuracy. When the temperature increases, the impurities evaporate, the sensitivity increases, and the signal increases; on the contrary, it decreases. As a result, data is unstable. Generally speaking, after excluding the quality problem of the flowmeter itself, most of them are field installation problems. For common speed flowmeters, the possible situations are: 1. Is the straight pipe section in front of the flowmeter long enough (generally 10) Times the inner diameter of the pipe), and must not contain elbows, bypass pipes or other impurities, flow blocking parts, etc. 2. Is the flowmeter installed upstream of the regulating valve? 3. Is there any vibration on site? 4. Is the flow rate too small to reach the lower limit of the flowmeter's measured value?
测焦炉煤气不稳定解决办法： 1、在仪表安装、连接过程中，应确保每一个环节的准确无误，其中包括安装前对现场的考察、安装过程中仪表接线、系统接地线等方面，从而确保检测到真实数据并能够准确输出。 Vortex flowmeter measuring coke oven gas instability solution: 1. In the process of instrument installation and connection, ensure that each link is accurate, including site inspection before installation, instrument wiring during installation, and system ground wire And other aspects to ensure that real data is detected and accurately output. 2. For the measurement system in operation, the method of “dual-track measurement, comparison and confirmation”, and the “replacement method” can be used to confirm and eliminate the measurement instrument failure in operation. 3. Regularly drain the pipeline, especially the water before the straight pipe section, and set a special person to discharge it regularly according to the specific conditions, reduce the water in the metering pipe section as much as possible, and eliminate the pulsation in the fluid to the maximum extent. 4. Strengthen the management of the measurement system data, set the timing printing function, and analyze the operation of the instrument based on the printed data combined with the production status. 5. Regularly clean the instrument as a whole. If necessary, purge the sensor head to avoid condensation of impurities at the sensor head. In the cold season, adding a heat tracing device to the metering straight pipe section and the meter part is also beneficial to alleviate the condensation of impurities at the metering meter.