Roller Bearing Axle Box
Brief Description :
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Roller bearings are of three types - Cylindrical, Spherical and Tapered.
(a) Cylindrical Roller Bearing :
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Rollers of these bearings are cylindrical in shape. These are provided in BEML Coaches, some engines (viz. WAG7, WDM3D etc.) and some wagons viz. BOX, BCX, BRH, etc.
Fig.: Roller Bearing Axle Box
(b) Spherical Roller Bearing :
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Spherical roller bearings are also called self-aligning roller bearings. When either due to curve or side oscillations, the rollers get displaced, the rollers automatically align themselves to their central position. The bearing consist of an outer ring having a continuous spherical race way within which operate two rows of barrel shaped rollers, which in turn are guided by an inner ring with two raceways separated by a centre rib.
In this type of bearing, diameter of rollers at the ends are slightly lesser than diameter at the centre.
Fig.: Spherical Roller Bearing
Fig.: Spherical Roller Bearing
The axle boxes can tilt up to 20. The roller bearings are so designed that they can get out of alignment by 2 to 3 mm without any detriment to their performance.These type of bearings are used in ICF all coil & some engines.
Fig.: Spherical Roller Bearing
(c) Tapered Cartridge Roller Bearing :
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These bearings are designed to take both radial and lateralloads. It consists of 2 rows of tapered roller bearings kept apartby a spacer ring over the inner race. During therun the outer race is held firm in the adaptor and the inner racerotates along with the axle and the roller bearings, rotating aboutthe axis of journal. But moment of any defect, the outer ringstarts rotating under the adapter producing a loud whistling noiseand thus saves the train from any serious disaster and alsosaves the wheel tread from skidding etc. These are provided insome engines, some wagons viz BOXN, BCN etc. and LHB coaches.
Fig.: Tapered Cartrdige Roller Bearing
Fig.: Tapered Cartrdige Roller Bearing