How to do motor bearing chamber machined surface integrity? This must look at

Machined surface integrity ( SurfaceIntegrity) Refers to parts processing surface quality, mainly including formation after machining surface roughness, surface residual stress, and processing of metamorphic layer ( Hardening, phase transformation, defects, etc. ) 。 And the surface roughness is one of the important index to assess the integrity of the machined surface, the surface roughness of the bearing chamber will directly affect the bearing with resistance, wear resistance, friction coefficient, fatigue strength and service life. Affect the reliability of the motor core technology has two: one is the insulation performance, the second is bearing running stability. Two motor bearing installed on both ends of the bearing chamber, respectively, so the bearing chamber of machined surface integrity directly affects the quality of bearing assembly. Along with the progress of The Times, the rail transit industry of the bearing chamber surface roughness quality put forward higher request, from past Ra = 3. 2 microns to 1. 6μm。 Therefore, how to effectively reduce the surface roughness is an important research topic in the rail transit industry. In the past two years, my company to zhuzhou electric locomotive co. , LTD. , zhuzhou lian cheng group co. , LTD. Jointly launched 'based on the research on the effects of different processing methods on the surface quality', has obtained certain achievements, this article will be part of the results to share with readers. 1, turning processing due to the limitation of equipment conditions, some of the larger dimension bearing chamber can only use cutting way to complete the final finishing, such as the exchanges of locomotive traction motor end cover, the overall dimensions of phi 900 mm or so, therefore, choose the rotary worktable for phi 1600 mm nc vertical lathe turning processing is more appropriate. In theory, the calculation formula of surface roughness value for Ra = 1000 & # 65381; f2/8･ R = 125･ f2 / R ( μm） , thus it can be seen that the feed rate f is smaller, the greater the cutting tool radius R, the Ra value is smaller, from figure 1 also can clearly see, Ra value and the relationship between f and R, if you take f = 0. 1毫米/ r, r = 0。 8 mm, Ra = 1. 56 microns, can satisfy the Ra = 1. 6 microns. But the actual machining process, due to the precision of the workpiece material, machine tool, the influence of rotating speed and devolop tumor, Ra actual values are often larger than the theoretical value. The following end cover of the two kinds of different material. ( 1) The end cover turning processing of cast steel material. Actually, by turning method can achieve high surface roughness is the most economic way, therefore, should strive to make an issue of cutting tools and cutting parameters. We chose walter two point arc R0 respectively. 4 mm and R0. 8 mm c-shaped steel blade, respectively according to the parameters of table 1 arrangement of experiment, through the statistical analysis, several conclusions: (1) when the feed rate is less than 0. 15 mm/n, the surface roughness value, can get ideal Ra = 1. 6 microns, as shown in figure 2. (2) the surface roughness value and the correlation of cutting speed and cutting depth is not big, but the higher the cutting speed, Ra value has a tendency to reduce. (3) chip breaker groove on the cutting edge of the blade is processed steel the key to achieve the desired surface roughness value, and the proper cutting depth can make better chip breaker, and avoid the secondary damage on the surface of the chip for processing, as shown in figure 3 cutting model, and the surface quality of the light. (4) with repair the car light blade blade will further reduce the surface roughness value. In addition, we also use a blade for the circular walter import cylindrical turning tool, the blade is 6 mm in diameter, when turning in the same parameter, the bearing chamber surface obtained the very good effect, measuring the Ra value at zero. Under 6 microns. ( 2) The end cover turning processing of cast iron material. As shown in figure 4 is cast iron material of a certain type of locomotive motor end cover, bearing chamber is only 190 mm diameter, turning the linear velocity is relatively low, to the surface of car gets light. We choose a point arc as R0. 8 mm C shape iron blade similar experiment was carried out, to reduce test times, using the orthogonal experiment method to study, to set the number of factors to 3, level number is 3 set, look-up table L9 ( 34) , the data and analysis results are shown in table 2. 2, grinding small end cover is not affected by the size of the equipment, the method of grinding can be taken to improve the quality of surface of the bearing chamber, such as a certain type of emu motor end cover, the surface quality of the higher request such as size, form and position tolerance, adopts the method of grinding is ideal process. In order to select the most suitable grinding parameters, we impact on the four parameters, the interactive combination experiment conclusion for Ra value 0 in all. Within 6 microns, of which the effect of grinding wheel size on the surface roughness value Ra, the largest depth of grinding, grinding wheel speed, workpiece speed affect the minimum, the concrete influence law as shown in figure 8. ( 1) Rolling processing. ( 2) Mg can be processed. 3. Conclusion through the research on the application of several processing methods, the process parameters of different processes on the experiment and optimized for the machining surface quality of the traction motor bearing chamber design new requirements, can be economical to choose suitable processing technology to achieve. 【 Warm prompt. 【 The bearing network] Some information from the Internet, and strive to secure timely, accurate, aims to deliver more information, does not represent our views to its approval or responsibility for their authenticity. If this net reprint information involves the issues such as copyright, please contact with this net. Tel: 0571 - 81630205. Tags: production and processing