Page 347 - The Tribology Handbook

Selection of lubrication systems c13

METHODS OF SELECTION

Table 13.1 Oil systems Table 13.3 Relative merits of grease and oil systems

=YP. Characterzstics Application Component or
performance Grease Oil
Hand Oil can Simple bearings, requirement
Type D Small numbers, __ ~___ __________
T low duty, Removing heat No Yes. Amount
0 easy access depends on
T- __~_____ system
A Centralised Intermittent feed Small heat
L Type D removal, Keep out dirt Yes. Forms own No. But total loss
difficult access, seal systems can
L large numbers flush
0 _______ .___~- -___~
S Mist Aerosol spray. Rolling bearings, Operate in any Yes. Check No. Unless
S Tvpr H mechanisms attitude design of specially
______.______ grease valves designed
s Splash Lubrication by Enclosed
E Type G mist mechanisms, Plain bearings Limited (slow Extensive
L gearboxes speed or light
F __-_~ load)
Dip Ring or disc Plain bearings- ~-
C TypeF systems. Oil slow or Rolling bearings Extensive Extensive
0 circulates moderate duty
N Sealed rolling Almost universal No
bearings
T Wick Pad or wick feed Plain bearings, ~-
A Type E from low duty.
I reservoir- Light loaded Very low No. Except for Yes (check pour
N total loss or mechanisms temperatures some special point of oil)
E limited greases
D circulation
Very high No. Except for Yes. With correct
Circulating Oil from tank or Almost all temperatures some special system
Type J sump fed by applications greases
pressure pump where cost is -
to bearings justified Very high speeds No. Except small Yes
or sprays rolling
bearings

Very low or Yes Hydrodynamic
intermittent bearings-
speeds iimi ted.
Table 53.2 Grease systems Hydrostatic
bearings- yes
7ype Characteristics Applications
____ Rubbing plain Yes Yes. With limited
Non Bearings packed Rolling bearings, bearings feed
replenishable on assembly. some plastic
Type '4 Refilling bushings
impossible
without
stripping

Local - hand Grease nipple to Small numbers,
Type B, each beariilg easy, access,
cheap Table 13.4 Selection by heat removal
___ ._______~____________
Centralised - Feed pipes Reasonable System Effect
hand brought to nu rn bers. -
Type B, manifold or lna((wihIc Total loss grease or oil Will not remove heat
Pump bearings -
Dip or splash Will remove heat from hot spots.
Centralised - Grease pump Large numbers, Will remove some heat from the
automatic feed to bearing important body of the components
Type c and sets of bearings, great __
bearings from distances. Mist Will remove considerable heat
automatic Where frequent __ __~~_____
Pump relubrication Recirculating. Oil May be designed to remove almost
is required any amount of heat
C13.2