大口径钢管圆度测量喷标系统设计与误差补偿研究

Error Compensation and Design of Roundness Measurement and Stenciling System for Large Diameter Steel Pipe

摘要:

为满足大口径钢管测量精度的需要，设计了一种龙门架式钢管在线测量及喷标系统。利用龙门架两侧立柱激光传感器的竖直运动，测量钢管截面外径上点的坐标，利用最小二乘法求其圆心坐标，采用近似直径法求取该截面的最大直径和最小直径，从而求得该截面的圆度。实例证明该系统及数据处理算法可实现钢管外径及圆度的测量，并具有相当高的精度。对测量结果进行误差分析，得知影响测量结果的主要来源是钢管的摆放姿态，通过投影及坐标变换对误差进行补偿，补偿后结果得到了一定的改善，从而验证了误差分析的合理性和补偿方法的可行性，该系统可用于大口径钢管的在线测量。

Abstract:

In order to satisfy the accuracy measurement demand of large diameter steel pipe, a gantry system for on-line measurement and stencil was designed. The coordinates of outer diameter points of the section could be measured by utilizing the vertical motion of laser sensor installed inside column of gantry. Coordinate of circle center was obtained by using least square method. The maximum and minimum of diameter were obtained by approximate diameter method, and then the roundness could be calculated. An example proved that the proposed system and data processing could be used to measure the outer diameter and roundness with high precision. Analysis of result showed that the gesture of steel was the main source of the error, which could be compensated through coordinate transformation and projection. It was verified the rationality of error analysis and the feasibility of compensation method. This system could be used for on line measurement of large diameter steel pipe.