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SKF bearing greases: The perfect solution
for every application
Even the very best bearing can only show optimum performance when it is
lubricated correctly. Here, it is extremely important to choose the
right bearing grease and to apply the most suitable lubrication
intervals and methods. This realisation has prompted SKF, the world's
leading manufacturer of rolling bearings, to look intensively into the
subject of lubrication. SKF engineers consider grease to be a
"fundamental" component of the bearing arrangement and thus, as
important as the bearing, housing and sealing. SKF's vast experience in
the development of rolling bearings forms the basis for the development
of a special range of lubricants, the superior quality of which is
obtained through continuous testing and studies.
The strict standards and testing
parameters developed and applied at the SKF Engineering and Research
Centre have become internationally recognised benchmarks for bearing
greases. The comprehensive range of SKF bearing greases is the result of
many decades of research and development. Each individual lubricant is
precisely adjusted to the respective field of application.
SKF sets the standard
Tangible performance parameters mean more to SKF than the chemical
composition of the lubricant. The chemical composition is not the only
factor in determining the quality of a particular grease, since modern
lubricants are extremely complex. SKF has set the standards for
developing special testing parameters.
Bearing grease selection
Incorrect lubrication accounts for up to 36 % of premature bearing
failures. All–purpose greases are inadequate for specialised bearing
needs and can cause problems rather than be beneficial. Bearing
applications have wide variations of operating conditions and correct
lubrication calls for matching the grease precisely to the application.
Bearing greases help ensure smooth,
trouble–free operation and maximum reliability even under the most
extreme conditions. They help prevent contamination from penetrating the
bearing, cushion any shock loads and protect against corrosion.
Selecting the right bearing grease for a certain application is
essential for achieving the maximum service life of a bearing.
Selection criteria for correct lubrication
include bearing type and size, temperatures, speeds and loads, as well
as the desired service life and re–lubrication intervals.
SKF Traffic light concept and Grease
Performance Factor
The temperature range over which a grease can be used depends largely on
the type of base oil and thickener used as well as the additives. The
relevant temperatures are schematically illustrated in the following
diagrams in the form of a “double traffic light”.
Operating temperature range of greases:
LTL – Low–temperature limit:
The lowest temperature at which the grease will allow the bearing to be
started up without difficulty.
LTPL – Low–temperature performance
limit:
Below this limit, the supply of grease to the contact surfaces of
rolling elements and raceways may become insufficient. Values are
different for roller and ball bearings.
HTPL – High–temperature performance
limit:
Above this limit the grease will oxidise in an uncontrolled way, so that
grease life cannot be determined accurately.
HTL – High–temperature limit:
When exceeding this limit, the grease loses its structure permanently
(e.g., the dropping point for soap–base greases).
Effect of temperature on grease
functioning
The values shown in these diagrams are
based on extensive tests conducted in SKF laboratories. These tests
allow us to accurately determine the temperature range of the SKF
bearing greases given in the selection charts included in this
catalogue.
The results of these tests are also used
to evaluate the grease life. The performance of each grease is then
translated into a Grease Performance Factor (GPF). Greases with highest
values offer the longest life. This factor, used in correlation with the
SKF re–lubrication diagram (see SKF General Catalogue GC 5000), allows
you to determine the correct re–lubrication intervals for the chosen
grease.
Re–lubrication intervals
Choosing the right bearing grease for a certain application is critical
to bearing performance. Applying the correct quantity of grease at the
right intervals is of equal importance. Over– or under–greasing as well
as inadequate lubrication methods can shorten the bearing’s service
life. For determining the right amount of grease and the correct
re–lubrication intervals for a specific application, SKF has developed
DialSet, a simple computerised re–lubrication calculation program.
Calculated re–lubrication intervals are based on the latest lubrication
theories published in the SKF General Catalogue (GC 5000) and depend on
bearing type used, application conditions and properties of selected
bearing grease.
Lubrication methods
The lubrication method used is equally important to the right bearing
grease, quantity and lubrication intervals. Using lubricators, manual or
automatic, facilitates proper lubricant supply to the application.
Maintaining cleanliness when lubricating bearings is crucial, as
contamination can cause the bearing to fail prematurely.
Using a grease meter in combination with a
grease gun or pump during manual lubrication helps ensure the supply of
the right quantity of grease. SKF’s range of grease guns, pumps and
lubrication accessories is designed for contamination–free grease supply
as well as ease–of–use.
Continuous lubrication using automatic lubricators, single or
multiple–point, provides the application with consistent and controlled
supply of bearing grease. This reduces the risk of over– or
under–greasing and positively contributes to optimising the bearing’s
service life. Additionally, automatic re–lubrication reduces the risk of
contamination. Around the clock solutions offered by SKF, such as SYSTEM
24 and SYSTEM MultiPoint, provide precise and reliable grease supply,
exactly adjusted to the application’s needs.
SKF bearing greases and their applications
SKF Greases
LGMT 2
SKF general purpose industrial and
automotive bearing grease
LGMT 3
SKF general purpose industrial and
automotive bearing grease
-
Bearings >100 mm (3,9 in) shaft size
-
Outer bearing ring rotation
-
Vertical shaft applications
-
Continuous high ambient temperatures
>35 °C (95 °F)
-
Propeller shafts
-
Agricultural equipment
-
Car, truck and trailer wheel bearings
-
Large electric motors
LGEP 2
SKF high load, extreme pressure (EP)
bearing grease
-
Pulp and paper making machines
-
Jaw crushers
-
Traction motors for rail vehicles
-
Dam gates
-
Work roll bearings in steel industry
-
Heavy machinery, vibrating screens
-
Crane wheels, sheaves
LGFP 2
SKF food compatible bearing grease
LGFB 2
SKF food compatible, high load bearing
grease
LGEM 2
SKF High viscosity bearing grease with
solid lubricants
-
Rolling element bearings running at
low speed and very high loads
-
Jaw crushers
-
Track laying machines
-
Lift mast wheels
-
Building machines such as mechanical
rams, crane arms and crane hooks
LGEV 2
SKF Extremely high viscosity bearing
grease with solid lubricants
-
Trunnion bearings on rotating drums
-
Support and thrust rollers on rotary
kilns and dryers
-
Bucket wheel excavators
-
Slewing ring bearings
-
High pressure roller mills
-
Crushers
LGLT 2
SKF low temperature, extremely high speed
bearing grease
-
Textile spinning spindles
-
Machine tool spindles
-
Instruments and control equipment
-
Small electric motors used in medical
and dental equipment
-
In–line skates
-
Printing cylinders
-
Robots
LGFL 1
SKF food compatible, low temperature
bearing grease
LGGB 2
SKF green biodegradable bearing grease
-
Agricultural and forestry equipment
-
Construction and earthmoving equipment
-
Mining and conveying equipment
-
Water treatment and irrigation
-
Locks, dams, bridges
-
Linkages, rod ends
-
Other applications where contamination
of the environment is a concern
LGWM 1
SKF extreme pressure low temperature
bearing grease
LGWA 2
SKF high load, extreme pressure, wide
temperature range bearing grease
LGHB 2
SKF high load, high temperature, high
viscosity bearing grease
-
Steel on steel plain bearings
-
Pulp and paper making machines
-
Asphalt vibrating screens
-
Continuous casting machines
-
Sealed spherical roller bearings
operating up to 150 °C (302 °F)
-
Withstands peak temperatures of 200 °C
(392 °F)
-
Work roll bearings in steel industry
-
Mast rollers of fork lift trucks
LGHP 2
SKF high performance, high temperature
bearing grease
-
Electric motors: Small, medium and
large
-
Industrial fans, including high speed
fans
-
Water pumps
-
Rolling bearings in textile, paper
processing and drying machines
-
Applications with high speed ball
bearings operating at medium and high temperatures
-
Clutch release bearings
-
Vertical shaft applications
-
Kiln trucks and rollers
-
Vibrating applications
LGET 2
SKF extreme temperature, extreme
condition bearing grease
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