Page 8 - Y-bearing-units

Contents

This is SKF ................................................................................................................. 2
SKF – the knowledge engineering company .................................................................. 4

Foreword .................................................................................................................. 11
1 Principles of selection and application ................................................................. 15
Designs ..................................................................................................................................... 16
Bearing terminology .......................................................................................................... 17
Y-bearings (insert bearings/wide inner ring bearings) .................................................... 18
Y-bearing units (mounted ball bearing, unit ball) ............................................................ 19
Selection of Y-bearing unit type.............................................................................................. 24
Locating on the shaft ......................................................................................................... 25
Loads .................................................................................................................................. 26
Seals ................................................................................................................................... 27
Permissible operating temperatures ................................................................................ 28
Speeds ................................................................................................................................ 29
Application note ................................................................................................................. 29
Selection of Y-bearing unit size .............................................................................................. 30
Load carrying ability and life.............................................................................................. 30
Selecting the bearing unit size using the life equations ................................................... 30
Equivalent dynamic bearing load ...................................................................................... 32
Dynamic bearing loads ...................................................................................................... 34
Requisite minimum load .................................................................................................... 34
Axial load carrying ability ................................................................................................... 34
Selecting the bearing unit size using the static load carrying capacity ........................... 35
Speeds ...................................................................................................................................... 38
Design of Y-bearing arrangements ........................................................................................ 40
Axial displacement ............................................................................................................. 40
Misalignment ..................................................................................................................... 42
Support surfaces ............................................................................................................... 42
Attaching to the support surface ....................................................................................... 43
Shaft tolerances ................................................................................................................. 43
Rubber seating rings.......................................................................................................... 45
End covers .......................................................................................................................... 47
Lubrication and maintenance ................................................................................................. 48
Grease fills .......................................................................................................................... 48
Relubrication ...................................................................................................................... 48
Relubrication intervals ....................................................................................................... 50

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