Automatic Collection Method of Machining Progress Information for Large-size Workpieces Based on Reference Power Curve

Abstract

Large-size workpieces are the common parts in the large equipment manufacturing industry. It is very significant for management staff to know the on-site machining progress information of the large-size workpieces in order to ensure the timely completion of jobs,improve production efficiency,optimize production management and support dynamic optimal schedule. Because the machining period of a large-size workpiece is long and in many cases only a single workpiece is machined,it is difficult to automatically collect the machining progress information. Based on this,the automatic collection method of machining progress information for large-size workpieces is proposed by using the power consumption information of the machine tool's main transmission system. The reference power curve of the machining workpiece is established based on the starting power database and the idle power database of the spindle transmission system of machine tools,which is obtained in advance,and the relative machining parameters,such as cutting parameters,workpiece material,and process time. Although the reference power curve is not exactly precise,the shape of the curve is enough to reflect the machining process of the workpiece. The machining progress information of the workpiece is collected by comparing the real-time data power curve with the reference power curve. The qualitative information is obtained by comparison of the shape characteristics of the two power curves ,and the quantitative progress data is calculated by analyzing the time of the two power curve. The case study of machining the large-size workpiece in a certain metallurgical equipment manufacturing workshop shows the method is practical.