Analysis And Research On Shafting And Top Components Of Large Heavy-duty CNC Roll Grinders

Center-locating CNC roll grinder is compared with traditional bracket-locating CNC roll grinders, because of high efficiency, high accuracy and high reliability, favored by the roller manufacturer. So it has a broad market prospects and development space. The spindle system and are the most critical parts of the support structure in heavy center-locating CNC roll grinder. Their structural strength and stiffness affects the overall performance of the grinding machine, which has a direct influence on machining precision.In this paper, the being developed MK84 type center-locating roller grinding machine in XianFeng Machine Tool Works was taken as the main body, the center assembly and spindle system and 100 t roll was taken as the object, with the finite element software ABAQUS and the finite element method as the tool, carried out analysis and research work. Main research work and results in the following 5 aspects:(1) Analysis of the relationship between the center load-bearing capacity and its influencing factors. Taking grinder center as the object, using control variable method and creating multiple sets of CAE analysis model, the influence law on center load-bearing capacity was researched from center angle, contact length and center friction coefficient. Stress, deformation, strain and contact force was used as the index of carrying capacity, and corresponding trend curve was fitted out according to index data, each index curve was studied and the optimal design interval of each influencing factor is obtained.(2) Analysis of the stress and deformation of the center bearing 100 t roll. Dynamic contact simulation analysis model was created and the workpiece was simulated by rotating the 10r/min, the stress, strain, deformation and stress of the center were analyzed. The results show that the center bear alternating stress, stress concentrate on grinding wheel groove, which is center of the risk of fracture section, and the deformation of head cantilever end is too large.(3) Center structure optimization. Study of the center statics results, the weak link are grinding wheel groove stress concentrate and head cantilever end deformation is too large. Taking the center diameter, the circle radius of the grinding wheel groove and the length of the head cantilever end as design variables, and step search optimization method was used to the center structure optimization design. The results show that the stress concentration distribution of the grinding wheel groove was improved, and the maximum deformation was reduced by 48.54%.(4) Statics analysis of the spindle system. Study on the stress distribution and deformation law of the spindle under bearing 100 t roll, the results show that the bigger stress area is located at the front end, the rear section of the solid region is smaller, and there is a big space for optimization. Because of spindle's middle and back end fixed support type, led to the deformation form of forward bending and back upturned.(5) Spindle topology optimization. Using ABAQUS the condition-based algorithm, topology optimization design was carried out for the internal material region of the rear section, which less contribution to the strength. After optimization, original spindle become a hollow structure, and the quality(3t) was reduced by 27.6%, about 0.83 t. The topology structure of the spindle can be provided reference for the structure optimization design and the second development.