Entity ferrule needle bearing and with or without inner ring needle roller bearings

Entity ferrule needle roller bearing structure is compact, small radial size, large load capacity, suitable for the radial dimensions constrained components, under the condition of the shaft or housing have oscillating motion is also widely used. Needle roller bearing A can bear radial load, can't carry axial load. When there are axial load, combined with other bearing, it does not limit shaft or the shell axial displacement. Needle roller bearing limit rotational speed is low, the main engine rate of revolution under the condition of high, should choose as far as possible with the needle roller bearing cage, compared with those of other types of rolling bearing in the radial direction under the condition of the same size, needle roller bearing load capacity is the largest, its rigidity is higher, but the friction torque is bigger also. This kind of bearing has a variety of structure and dimension series for journal or shell surface hardness of roll surface, the machining accuracy and surface roughness should be the same as the bearing ring. G2 grade needle assembly, grouped batch change quantity within 2 microns in diameter, in addition to the full needle bearing, adopt high rigid retainer, correctly guide the needle parallel to the axis. Without inner ring needle roller bearing RNA, NK model without inner ring needle roller bearing is suitable for the limited size of the radial components, because without the inner ring, and cooperate with the surface of the shaft neck directly as a rolling surface. Its surface hardness is not lower than HRC60, the surface roughness Ra value is not greater than zero. 63 microns, this kind of bearing does not limit the shaft or the shell axial displacement, limit rotational speed is higher. Have inner ring needle roller bearing type NA, NKl due to this kind of bearing inner ring no guard, so can be installed separately inner ring and outer ring, a full set of needle roller and cage, don't limit the shaft or the shell axial displacement. Because the needle roller with cage is separated, reduced friction, so can be used in high speed components.