Method and device for assessing machining accuracy of ultra-large type curved surface parts

Abstract

The invention discloses a method and a device for assessing the machining accuracy of ultra-large type curved surface parts. The method comprises the steps of performing data preprocessing to obtain relatively-evenly sampled data sets on the curved surfaces of the parts, initially positioning the sampled data sets according to the transformation relation between a measurement coordinate system and a theoretical coordinate system of a theoretical curved surface model so as to obtain initial iteration vectors roughly matched with the curved surfaces; utilizing the sampled data sets and the initial iteration vectors to solve the nonlinear optimization problem and obtain optimal coordinate transformation enabling the sampled data sets and the theoretical curved surface model to be matched; performing error analysis based on the sampled data sets and the optimal coordinate transformation and analyzing the machining accuracy of the ultra-large type curved surface parts. By adopting the method and the device for assessing the machining accuracy of the ultra-large type curved surface parts, assessment of the machining accuracy of the ultra-large type curved surface parts including steel safety casings of nuclear power plants and the like can be quickly, efficiently and accurately achieved.

Description

technical field [0001] Exemplary embodiments of the present invention generally relate to the evaluation of processing accuracy of super-large parts, and specifically relate to a method and device for evaluating processing accuracy of super-large parts. Background technique [0002] A lot of research has been done on the problem of machining accuracy evaluation of curved surface parts of general scale and shape. However, there is still no effective method to evaluate the machining accuracy of very large curved surface parts. A typical super large curved surface component is the steel plate of the steel containment vessel (CV) of a nuclear power plant. As an important nuclear secondary equipment unique to nuclear power plants (AP series), CV is an important equipment in the passive safety system and an important protection boundary in the nuclear island protection system. The containment contains the main process system equipment such as reactor, steam generator, and pressur...

AI Technical Summary

Problems solved by technology

In addition, when the data points (or ellipsoid) are fitted by the least squares method after coordinate transformation, the objective function will become very complex, non-linear, and sensitive to the initial value

Therefore, the linear optimization method (such as the linear least squares method) used in traditional technology cannot be applied to the evaluation of the machining accuracy of super large curved surface parts like CV steel plates.

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