Parker F11/12 Series F12-040 F12-060 F12-080 F12-090 F12-110 F12-125 F12-152 F12-162 Hydraulic Pump Motor F12-040-MS-SV-S-000-00

General information Bearing life can be calculated for that part of the load/ life curve (shown below) that is designated 'Bearing fatigue'. 'Rotating group fatigue and wear' and 'Other' caused by material fatigue, fluid contamination, etc. should also be taken into consideration when estimating the service life of a motor/pump in a specific application. Bearing life calculations are mainly used when comparing different frame sizes. Bearing life, designated B10 (or L10), is dependent of system pressure, operating speed, external shaft loads, fluid viscosity in the case, and fluid contamination level. The B10 value means that 90% of the bearings survive, at a minimum, the number of hours calculated. Statistically, 50% of the bearings will survive at least five times the B10 life

Bearing life calculation An application is usually governed by a certain duty or work cycle where pressure and speed vary with time during the cycle. In addition, bearing life depends on external shaft forces, fluid viscosity in the case and fluid contamination. Parker Hannifin (Mobile Controls Division) has a computer program for calculating bearing life and will assist in determining F11 or F12 motor/pump life in a specific application

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