孔板流量计取压方式的研究

Research on Pressure Taking Mode of Orifice Flowmeter

孔板流量计是一种测量流体流量的差压类流量计,广泛应用于石油、化工、电力等领域。孔板流量计主要的取压方式为法兰取压、角接取压和径距取压,其取压方式是影响测量精度的重要因素之一,现如今没有一个选取取压方式的标准。该文通过实验的方式将孔板流量计分别采用法兰取压、角接取压、径距取压计算得到的流出系数与GB/T2624.2中给出的各种不同取压方式理论流出系数进行比较,由实验结果可知环室角接取压的测量精度最高。通过比较加工精度和现场环境等因素,给出了3种取压方式的适用条件。

Orifice flowmeter is a differential pressure flowmeter for measuring fluid flow,which is widely used in petroleum,chemical industry,electric power and other fields.The main pressure-taking methods of orifice flowmeter are flange pressure-taking,angular pressure-taking and radial pressure-taking,and their pressure-taking methods are one of the important factors that affect the measurement accuracy.At present,there is no standard for selecting pressure-taking methods.In this paper,the outflow coefficients of orifice flowmeter calculated by flange pressure,angular pressure and radial pressure are compared with the theoretical outflow coefficients given in GB/T2624.2 and the experimental results show that the measurement accuracy of angular pressure of annular chamber is the highest.By comparing the factors such as machining accuracy and field environment,the applicable conditions of three pressure taking methods are given.