The Design of Rolling Bearing Mountings

74 Rope return sheaves of a passenger ropewayIn this example of a passenger ropeway, eight sheavesare installed at the mountain station and another eightat the valley station including the sheaves in the valleystation tensioning weight pit. The sheave diameters are2.8 and 3.3 meters.Bearing selection, dimensioningThe valley station sheaves and the tensioning weightsheaves are fitted with spherical roller bearings FAG22234E. The sheaves at the mountain station are supportedby spherical roller bearings FAG 22240B.MB.The load on the bearings FAG 22234E installed in thetensioning weight sheaves is P = 65 kN each; with adynamic load rating C = 1,100 kN and a speed factor f n= 0.838, corresponding to a speed of 60 min –1 , theindex of dynamic stressing:f L = C/P · f n = 1,100/65 · 0.838 = 14.2.This shows that the bearings are more than adequatelydimensioned with regard to fatigue life.The one-piece sleeve carrying the bearings allows convenientchanging of the rope sheaves.Machining tolerancesThe outer rings carry circumferential load and require,therefore, a tight fit. To safeguard the spherical rollerbearings against detrimental axial preloading, the designis of the floating mounting type. The outer ringsare securely locked via the two covers by means of aspacer ring. The centre lip of sleeve H is slightly narrowerthan the spacer so that the sheave can float axiallyon the sleeve via the loosely fitted inner rings. Thesleeve is locked to prevent it from rotating with the innerrings.Sleeve to g6; hub bore to M6;The sleeve has a sliding fit on the shaft.Lubrication, sealingGrease lubrication with FAG rolling bearing greaseArcanol L186V. Relubrication by means of lubricatingholes in the shaft.A shaft seal ring in the covers provides adequate protectionagainst contamination.FAG 104