INA angular contact ball bearing of cold extrusion technology

Cold extrusion plastic deformation of metal material is used to obtain the required shape, size, and a kind of mechanical parts forming process, so the blank size is equal to the volume of parts. Determination of blank diameter size is critical, it determines the deformation degree of the milled parts, can ensure that the diameter of the reasonable size twice extrusion deformation degree of balance, to reduce the deformation resistance of the extrusion, avoid extrusion defects imported bearing parts, prolong the service life of mould. According to the experience of the extrusion of bearing steel, complex beginning part is crowded section cut rate is best controlled within 50%. One, the cold extrusion process according to the shape and dimension precision angular contact ball bearing parts, the preparation of high quality billet lathe cutting method is adopted, the billet after annealing softening, tumbling, pickling, phosphating, and then saponification process, finally by extruding. Two, on the strength theory and design calculation of cold extrusion concave die, the die is generally regarded as the uniform pressure thick wall cylinder. To work INA bearing internal pressure thick wall cylinder, appeared at the inner diameter is too large of the tangential stress is the main cause of die cracking and damage, and in the strength calculation and checking, should check each synthesis of stress of the inner surface, make it less than the tensile yield limit of material. Three, the maximum shear stress strength theory, material damage reason is that the maximum shear stress, as long as the maximum shear stress reaches a certain value ( When the simple tension compression destruction of maximum shear stress) , material will be destroyed. To reduce the vibration of the rolling surface grinding superfinishing, obtain good surface processing precision and surface shape grain quality in order to reduce vibration, super grinding machine tools must have good vibration resistance, lathe bed and other important structures with vibration absorption, superfinishing machine oil stone oscillation system has good vibration resistance; Raising the speed of the grinding, grinding abroad 6202 outer raceway generally used 60000 motorized spindle, grinding speed of 60 m/s above, domestic generally much lower, mainly restricted by main shaft and main bearing performance. Small when high speed grinding, grinding force, grinding metamorphic layer thin, is not easy to burn, and can improve the machining precision and efficiency, a great influence on low noise angular contact ball bearing; The spindle static stiffness and speed characteristic of low noise INA bearings grinding vibration influence is very big, the higher the stiffness, the less sensitive to the change of grinding force in grinding speed and grinding system vibration is smaller; To improve the spindle bearing stiffness, the random dynamic balance technology, improve the grinding spindle vibration resistance. Foreign grinding head vibration velocity ( Such as Gamfior) About one over ten of the domestic general spindle; Improve the quality of grinding wheel abrasive cutting performance and dressing is very important. Grinding wheel sharpening stone in our country at present the main problem is the organizational structure uniformity is poor, the serious influence low noise angular contact ball bearing grinding processing quality; Cooled sufficiently, improve the filtering accuracy; Improve the feed of essence to system resolution, reduce feed inertia; Reasonable grinding machining process parameters and machining process are the factors that can not be ignored, grinding allowance, shape tolerance strictly, small and medium-sized ball bearing outside diameter is unfavorable use ultra lapping, coarse fine grinding ultra should not be separated, to ensure the good surface quality. INA bearing installation method, because the bearing structure, cooperate, conditions vary, in general, as more as the axis of rotation, so the inner circle need interference fit. Cylindrical hole bearing, multi-purpose press pressure into, or multi-purpose hot charging method. Taper hole, installed directly on the taper shaft, or use the socket installation. When installed on the shell, clearance fit more commonly, outer ring have surplus quantity, usually use the pressure into the press and or have shrink fit method of cooling after installation. Use dry ice as coolant, shrink fit installation, the moisture in the air condenses on the surface of angular contact bearings. So, need a good rust prevention measures.