Measuring device and measuring method for geometric parameters of inner wall of elbow

Abstract

The invention relates to a measuring device and a measuring method for geometric parameters of an inner wall of an elbow, belonging to the testing instrument and meter field. The measuring device is provided with three motional freedom degrees and one rotational freedom degree, a measuring pin is installed at the tail end of a measuring arm for measuring overhanging and can rotate around the axle center of the measuring arm, and the pivot angle of the measuring pin can be manually regulated. In the measuring method for the geometric parameters of the elbow, the inner diameter and the bending radius of the elbow are measured by the measuring device, and the measuring process sequentially comprises the following steps: determining the center line plane of the elbow, measuring the bending radius and measuring the inner diameter of the elbow. The measuring method solves the problem on the measurement of the geometric parameters of the inner cavity of the elbow, and no locating surface needs to be additionally arranged in the measuring process, thus the invention achieves a large caliber application scope, and is especially applicable to occasions having higher requirements for the measurement accuracy of the geometric parameters of the elbow.

Description

technical field [0001] The invention belongs to the field of testing instruments and meters, and in particular relates to a measuring device and a measuring method for geometric parameters of the inner wall of an elbow, which are used for measuring the bending radius and the inner diameter of the elbow. Background technique [0002] Elbow flowmeter is a new type of differential pressure flowmeter, which uses the pressure difference between the inside and outside of the elbow at the right-angle bend on the pipeline and the geometric parameters of the inner wall of the elbow to calculate the fluid flow in the pipe. The ratio of the radius of curvature R of the centerline of the inner wall of the elbow to the diameter D of the inner wall of the elbow is called the bend diameter ratio K. Bend-to-diameter ratio is the most important geometric parameter affecting the flow characteristics of elbow flowmeters. Therefore, how to accurately measure the bending radius and inner diamet...

AI Technical Summary

Problems solved by technology

[0004] Since the geometric parameters of the outer wall of the elbow have no effect on the velocity and pressure of the fluid in the pipe, usually only the inner wall of the pipe needs to be processed and measured. The wall thickness of the elbow is not uniform, and it is difficult to determine the rotation center and centerline of the elbow by manual methods. Universal measuring tools such as dial indicators and vernier calipers cannot accurately measure the inner diameter and bending radius of elbows

This seriously affects the test accuracy of the elbow flowmeter

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