Tham khảo tài liệu 'fag_rolling_bearing_lubrication part 6', kỹ thuật - công nghệ, cơ khí - chế tạo máy phục vụ nhu cầu học tập, nghiên cứu và làm việc hiệu quả | Lubricant Supply Oil Fig. 58 The bottom rollers of the spherical roller bearing are immersed in a small oil sump. Oil losses are compensated for by oil supplied from the larger oil sump below the spherical roller bearing. The ring oiler R has a diameter which is considerably larger than the shaft diameter it dips into the lower oil sump which is not connected with the bearing. In operation the ring oiler R turns on the shaft and feeds the oil to the bearing. Excess oil returns to the lower oil sump through bores A. Ring oilers can be used up to a speed index of n dm 400 000 min-1 mm. At higher speeds the ring oiler shows heavy wear. Fig. 59 Like all bearing types with an asymmetrical cross section tapered roller bearings have a pumping effect. It depends heavily on the circumferential velocity of the bearing and can be utilized for circulating oil lubrication. The drain holes must be large enough to prevent oil retention at the bearing sides. Fig. 60 Vertical high-speed spindles are sometimes designed with a tapered end or a separate cone which rotates along with the spindle is fitted to them the tapered end dipping into the oil reservoir. The oil is pumped up through the gap S into the circular groove from where it flows into an overhead dispenser. With this arrangement relatively large oil quantities can be supplied if the feed height is short and the oil viscosity is low. Fig. 61 In gearboxes transmissions etc. the oil thrown off the gears often provides for adequate bearing lubrication. However the oil must actually enter the bearings under all operating conditions. In the example shown the oil thrown off is collected in a pocket above the cylindrical roller bearing and fed to the bearing through grooves. A baffle plate is arranged beside the cylindrical roller bearing. It ensures that a certain amount of oil is always retained in the bearing and that the bearing is lubricated at start-up. Figs. 62 and 63 With oil jet lubrication the oil jet is forced between .
