Page 20 - The Tribology Handbook

Selection of journal bearings A2

Selection of journal bearings with continuous rotation for special environmental conditions

Tjpt of btarin,i High &m@. Low hp. Vacuum Wet and Dirt ana' External GPe of
humid dust Vibration bearing
Rubbing plain Goodupto Good Excellent Good but Good but Good
bearings the tem- shaft must sealing
(non-metallic) peratuire be incor- helps
limit of rodible
material
Porous metal Poor since Fair; may Possible Good Sealing Good
plain bearings lubricant havehigh with essential
oil oxidises starting special
impregnated torque lubricant
Rolling Consult Good Fair with Fair with Sealing Fair;
bearings makers special seals essential consult
above lubricant makers
150°C

Fluid film plain Good to tem- Good; may Possible Good Goodwith Good
bearings perature have high with seals and
limit of starting special filtration
lubricant torque lubricant
Externally Excellent Good No ; Good Good ; Excellent
pressurised with gas lubricant excellent
plain beariings lubrication feed affects when gas
vacuum lubricated
General Watch effect of thermal Watch Watch
comments expansion on fits corrosion fretting

Selection of journal bearings with continuous rotation for special performance
requirements
Accurate Axial load Low Standard simple aype
Tyje of bearing radial capacip as starting Silent running parts lubrication of
bearing
location well torque available
Rubbing plain Poor Some in Poor
bearings most
(non-metallic) cases

Porous metal Good Some Good Excellent YeS Excellent
plain
bearings oil1
impregnated
Rolling bearings Good Yes in most Very good Usually Yes Good when
cases satis- grease
factory lubricated

Fluid film plain Fair No ; Good Excellent Some Usually
bearings separate requires a
thrust circulation
bearing system
needed
Externally Excellent No ; Excellent Excellent No Poor ;
pressurised separate special
plain thrust system
bearings bearing needed
needed

A2.2