CARBÂ® toroidal roller bearings â a revolutionary ... - Acorn Bearings

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1 Product information 2 Recommendations 3 Product data Page ............. 3 Page ............. 12 Bearing data Cages Depending on their size, CARB toroidal bearings are fitted with one of the following as standard (➔ fig 5 ): • injection moulded cage of glass fibre reinforced polyamide 4,6, roller centred, designation suffix TN9 (a), • window-type steel cage, roller centred, no designation suffix (b), • window-type brass cage, roller centred, designation suffix M (c), or • machined brass cage, inner ring centred, designation suffix MB (d). CARB bearings with polyamide 4,6 cages can be operated at temperatures up to +120 °C. With the exception of a few synthetic oils and greases with a synthetic oil base, and lubricants containing a high proportion of EP additives when used at high temperatures, the lubricants generally used for rolling bearings do not have a detrimental effect on cage properties. For bearing arrangements that are to be operated at continuously high temperatures or under arduous conditions, SKF recommends using steel or brass cages. Influence of operating temperature on bearing material All CARB bearing rings undergo a special heat treatment so that they can operate at higher temperatures for extended periods without causing detrimental dimensional changes. Of course, the maximum temperature is dependant on the cage, lubricant and seals, However, the rings are heat treated to withstand 200 °C for 2 500 h, or for short periods, even higher temperatures. Minimum load In order to provide satisfactory operation, CARB toroidal roller bearings, like all ball and roller bearings, must always be subjected to a given minimum load, particularly if they are to operate at high speeds or are subjected to high accelerations or rapid changes in the direction of load. Under such conditions the inertia forces of rollers and cage, and the friction in the lubricant, can have a detrimental effect on the rolling conditions in the bearing arrangement and may cause damaging sliding movements to occur between the rollers and the raceways. The requisite minimum load to be applied to a CARB toroidal roller bearing with cage can be estimated using P 0m = 0,007 C 0 and for a full complement bearing using P 0m = 0,01 C 0 where P 0m = minimum equivalent static load, kN C 0 = basic static load rating, kN (➔ product tables) In some applications it is not possible to obtain the requisite minimum load. However, for caged bearings that are oil lubricated, lower minimum loads are permissible. These loads can be calculated when n/n r ≤ 0,3 from P 0m = 0,002 C 0 and when 0,3 < n/n r ≤ 2 from Fig 5 P n 0m = 0,002 C 0 ( 1 + 2 n – 0,3 r ) where P 0m = minimum equivalent static bearing load, kN C 0 = basic static load rating, kN (➔ product tables) n = rotational speed, r/min n r = reference speed, r/min (➔ product tables) When starting up at low temperatures or when the lubricant is highly viscous, even greater minimum loads than P 0m = 0,007 C 0 and 0,01 C 0 respectively may be required. The weight of the components supported by the bearing, together with external forces, generally exceeds the requisite minimum load. If this is not the case, the CARB bearing must be subjected to an additional radial load. Equivalent dynamic bearing load For CARB toroidal roller bearings P = F r Equivalent static bearing load For CARB toroidal roller bearings P 0 = F r CARB bearings on adapter sleeves For CARB bearings with a tapered bore, SKF also supplies adapter sleeves (➔ fig 6 ) and withdrawal sleeves. These enable the bearings to be quickly and easily secured on smooth or stepped shafts. Detailed information on CARB bearings on adapter sleeves can be found in the product table starting on page 58. Where appropriate, modified adapter sleeves of the E, L and TL designs, e.g. H 310 E, are available for CARB toroidal roller bearings, to prevent the locking device from fouling the cage. With adapter sleeves of • series H … E, the standard lock nut with locking washer (KM + MB) is replaced by a KMFE lock nut (➔ fig 7 ), a b c d Cages for CARB bearings 42
1 Product information 2 Recommendations 3 Product data Page ............. 3 Page ............. 12 Designation scheme • series OH … HE the standard lock nut HM is replaced by a HME nut with a changed front face (➔ fig 8 ), • L-design differs from the standard design in that the standard lock nut KM and locking washer MB have been replaced by a KML nut with MBL locking washer; these have a lower sectional height (➔ fig 9 ), • TL-design, the standard HM 31 lock nut with MS 31 locking clip have been replaced with the corresponding HM 30 nut and MS 30 locking clip; these have a lower sectional height. CARB bearing on adapter sleeve Examples C 2215 TN9/C3 C 22 15 TN9/C3 C 3160 K/HA3C4 C 31 60 K HA3C4 Prefix C BSC- Bearing with standardised dimensions Special bearing ISO-Dimension Series 39, 49, 59, 69 ISO Diameter Series 9 30, 40, 50, 60 ISO Diameter Series 0 31, 41 ISO Diameter Series 1 22, 32 ISO Diameter Series 2 23 ISO Diameter Series 3 Size identification 05 × 5 25 mm bore diameter to 96 × 5 480 mm bore diameter from /500 Bore diameter uncoded in millimetres Diagram 2 3 Fig 6 Bore – Cylindrical bore K Tapered bore, taper 1:12 K30 Tapered bore, taper 1:30 Other features Fig Fig 7 8 Sleeve of series H … E with a KMFE lock nut – Steel window-type cage – Normal radial internal clearance C1 Radial internal clearance smaller than C2 C2 Radial internal clearance smaller than Normal C3 Radial internal clearance greater than Normal C4 Radial internal clearance greater than C3 C5 Radial internal clearance greater than C4 2CS Sheet steel reinforced nitrile rubber seals (NBR) on both sides of the bearing 1) 2CS5 Sheet steel reinforced hydrogenated nitirile rubber seals (HNBR) on both sides of the bearing 2) HA3 Case hardened inner ring M Machined brass window-type cage MB Machined inner ring centred brass cage 2NS Highly efficient nitrile rubber seals on both sides of the bearing 2) TN9 Injection moulded cage of glass fibre reinforced polyamide 4,6 V Full complement of rollers (no cage) VG114 Surface hardened pressed steel cage VE240 Bearing modified for greater axial displacement 1) Bearings with CS seals are filled to 40 % of the free space in the bearing 2) Bearings with CS5 seals as well as with NS seals are filled to between 70 and 100 % of the free space in the bearing Sleeve of series OH … HE with a modified HME lock nut Designation scheme for CARB toroidal roller bearings Fig 9 Designation The complete designation of a CARB toroidal roller bearing is made up of • any supplementary designations used to identify certain features of the bearing. Sleeve of series H … L with a KML lock nut plus an MBL locking washer • the prefix C, • the ISO Dimension Series identification, • the size identification, and Diagram 2 shows the designation scheme and the meaning of the various letters and figures in the order in which they appear. 43
Page 1 and 2: CARB ® toroidal roller bearings -
Page 3 and 4: 1 Product information 2 Recommendat
Page 41: 1 Product information 2 Recommendat
Page 79 and 80: The sleeve is located on the shaft
Page 81 and 82: Condition monitoring equipment The
Page 83 and 84: Creating a new “cold remedy” In

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CARBÂ® toroidal roller bearings â a revolutionary ... - Acorn Bearings