TIMKEN tapered roller bearings can be installed in various forms. In different installation forms, there are various methods to set the bearing clearance to the required axial clearance or preload. In the back-to-back installation of the inner ring clearance device, usually only one inner ring is supported by a fixed shoulder, while the other inner ring is movable and supported by some kind of setting clearance device. The required bearing clearance can be obtained with a slotted nut (fig. 20). The nut is locked by a cotter pin. Nuts and washers must be sized to provide adequate support for the inner ring. The two cotter pin holes on the shaft, spaced 90 degrees apart, allow twice as many locked positions in one revolution of the nut, and therefore a correspondingly tighter bearing play. A self-locking nut, knurled washer, and lock washer can be used in place of the slotted nut (Figure 21). For the use of other lock nuts, see the Auxiliary Parts section of the Timken Tapered Roller Bearings Catalog. The bearing clearance can be set using the stake nut (fig. 22), which is locked by tapping the thin end into the keyway. The play shown in Figure 23 is obtained by means of bolts, spacers secured to the shaft ends and end caps. The end caps can be slotted to measure gasket clearance. A TDO bearing with an inner ring spacer (above the centerline, Figure 24) and a TNA bearing (above the centerline) are manufactured with a fixed internal clearance. As shown, TDO bearings have an inner ring spacer that is clamped onto the shaft by an end cap and shoulder. TNA bearings have the inner ring clamped directly onto the shaft by means of a shoulder. No additional clearance adjustment procedure is required in each case. During the face-to-face installation of the outer ring clearance setting device, usually only one outer ring is supported by the fixed shoulder, and the other movable outer ring can be adjusted by a suitable clearance setting device. An outer ring bushing (above the centerline, Figure 25) and an outer ring end cap (below the centerline) are shims for clearance, and the bushing or end cap is bolted. Clearance can be set by selecting an outer ring spacer and using end caps that are bolted to the housing (fig. 26). TDI bearings with outer ring spacers (fig. 27) can be provided with a specific fixed internal clearance by the outer ring spacer. The bearing clamps the outer ring and spacer ring through the outer ring end cap and the housing shoulder. No additional clearance adjustment process is required. Summary Compared to other types of bearings, one of the advantages of tapered roller bearings is that the clearance can be adjusted during installation. Manual setting of clearance has been accepted by many manufacturers and will continue to be used. However, due to cost and stricter performance requirements, more manufacturers prefer the method of automatically setting bearing clearance. It is best to choose the method of automatically setting the bearing clearance at the design stage. However, if the equipment has been designed and manufactured, one or a combination of clearance setting methods can also be used to improve the reliability of clearance setting and reduce assembly time. Contact a Timken bearing sales engineer for further support in selecting the appropriate method of automatically setting bearing clearance. The Qingdao Ruijing Electromechanical Equipment Co., Ltd. team can provide assistance in fixture design, prototype testing, and production process implementation.