Research On Recording And Automatic Judging Of Wheelset Press-fit Curve

Wheelset is a key moving component on the bogie frame in locomotive and vehicle, which combines two wheels with an axle together firmly at the mode of keyless and interference fit. There are three assembly modes:press-fit assembly, oil ing assembly and thermal assembly, press-fit assembly is in common use in China. Pressed qualified requirements have two:1.size requirements,2.curve requirements. Here, curve means press-fit curve which records the force and displacement signals during press-fit assembly.Aimed at the shortage of equipment existing, this paper has designed the curve recording and judging system of wheelset assembly machine which is suitable for status of our country, which relies on the opportunity of rapid development of high-speed railway. We used solution of digital storage, used the computer to control and store, data’s collection has used advanced, reliable computer boards. We can enter the parameters of the press-fit wheel into the computer, dynamic display the press-fit curve, and query and manage data, etc.In this article, we mainly analyzes the way of press-fit wheelset and the standard of curve’s eligibility, has achieved a function which can automatically determine press-fit curve’s quality; proposed outlier mining and smoothing method for press-fit curve, eliminate the insufficient of disturbance points, improve authenticity and accuracy of automatic judgment results. Compared to old curve recording system, this curve recording system’s display precision of press-fit curve and degree of automation recorded curves have been greatly improved.The main work of this paper is as follows:(1) Analyze the force change in wheelset press-fit process and the factors which affect the press-fit curve, provide theory basis for curve qualification judgment.(2) Complete hardware selection and design, such as pressure sensors, displacement sensors, data acquisition cards and so on. At the same time programming is to collect data efficient, which is based on C++Builder platform, a method is designed to improve the antijamming capability, which improved the accuracy of data collection.(3) The standard of foreign railway industry was analyzed and summarized, at the same time, with TB/T1463-2006, TB/T1718-2003and other railway industry’s standard of people’s Republic of China, a function that press-fit curve can be determined automatically was achieved in the program, it can judge the quality of the press-fit wheel correctly.(4) It establish a database of wheelset assembly machine’s curve recording system, the system has powerful permissions management, can automatic store information of wheel and press-fit data, at the same time can manage data.The system described in this paper has been successfully used in CNR railway vehicles Co., Ltd. and obtained favorable effect.