产品概述
文丘里管（Venturi Tube）
文丘里管的入口和出口均为流线型。标准设计配有均压环（在入口和喉部圆周设置多个取压孔并以环形环包围的结构）。
测量浆料等非均质液体时，为便于高效吹扫取压孔，通常拆除均压环。文丘里管被认为是最适合测量高固体浓度液体的差压式一次元件。
作为泵等设备验收试验的标准测量手段，单独校准的文丘里管与经校准的孔板测量管段一样，具有将取压口特性的影响也纳入校准的优点。
入口和喉部配有均压环的经典文丘里管，其试验数据的标准偏差为 0.3 ~ 0.4%；正确制造、安装的此类文丘里管，在管道雷诺数至 200,000 的范围内，95% 的安装与数据的一致性在 ±0.75% 以内。
English description
The Venturi tube is streamlined at both entrance and exit. Standard designs are equipped with piezo meter rings (i.e., multiple tap holes around the periphery of inlet and throat, surrounded by an annular ring). For measurement of slurries and similar nonhomogenous liquids, the piezo meter rings are usually eliminated to permit efficient purging of the pressure tap holes. The Venturi tube is considered the best type of head meter primary device for measuring liquids containing large concentrations of solids. As a standard measurement for acceptance tests on pumping and similar equipment, the individually calibrated Venturi tube has certain advantages. Like a calibrated orifice meter run, the calibration includes the effect of tap characteristics. The standard deviation of the test data, on classical type Venturi tubes with piezo meter rings at inlet and throat connections, is between 0.3 and 0.4%. The coefficients of properly constructed and installed Venturi tubes of this type should agree with the data within ±0.75% on any pipe Reynolds number down to 200,000 on 95% of the installations.
