Molykote® High Performance
Specialty Lubricants
Technical Training: “Machine components“
Dr Michael Schütz
Dr.
Content
•
•
Introduction
Components
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–
•
Bolts and studs
Springs
Rolling-element bearings
Sliding-contact bearings
Sliding guides and linear sliding systems
Seals
B d cables
Bowden
bl
Gears
Chains
Shaft-hub
Shaft
hub connections
Clutches
Ball joints
Press-fit joints
j
Maintenance and repair
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Introduction
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Introduction
StribeckDiagram
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Introduction
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Introduction: Glossary
•
•
•
•
•
•
•
•
Seizure, or Scuffing: Damage and wear to material surface through inadequate supply of
lubricant, or as a result of overloading.
g The lubricating
g film is broken ((more adhesive wear).
)
Scoring: Formation of trench-shaped marks (scratches) in the metal in the sliding direction
(more abrasive wear)
Fretting corrosion (or Fretting): Better described as "frictional wear", occurring at metallic
j i t and
joints
db
beatings
ti
d
due tto vibrations
ib ti
off very llow amplitude
lit d and
d hi
high
h ffrequency. A
As a rule,
l
the very small iron wear particles are quickly converted by oxygen into rust, eventually
causing seizure of the joint.
Stick-Slip:
p Stop-start
p
relative movements of two sliding
g surfaces,, caused byy the difference
in coefficient of friction between hydrodynamic and boundary lubrication.
Swelling Shrinkage: Under the action of lubricants, vapors or gases, sealing materials
made from rubber, elastomers, etc., can be negatively affected by swelling or shrinking.
S
Stress
cracks: Cracks
C
in materials ((being subject to high stresses)) caused by changes off
the surface structure after penetration of undesirable elements i.e. base oil of a grease
Running-in: Surface asperities of new sliding surfaces are modified (smoothened) during
the running
running-in
in period.
Routing of cable: Three-dimensional course of the cable in i.e. car body
80-3648-01
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Molykote® Specialty Lubricants
M h i lC
Mechanical
Component:
t Bolts
B lt and
d Studs
St d
Bolts and Studs
• Bolts are used to produce non-destructive releasable
connections consisting of two or more parts using one or
connections,
more bolts i.e. machine housings / tube flanges
80-3648-01
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Bolts and Studs – General
•
Lubrication Engineering:
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–
–
–
•
Frictional state: Boundary Friction
Contact zone: Line to area
Friction factor: goal 0.1 – 0.14, practical values: 0.15 – 0.35
Main Type of Lubricants: Pastes and AFCs
Failures:
– Fretting and seizure on bolts made of austenitic stainless steel (no oxide
layer)
– Fretting and seizure on bolts with galvanized surface (high friction factor)
– Broken bolts and stripped threads owing to scatter of friction coefficient
coefficient.
– Broken bolts due to stress cracks on thread surfaces.
•
Automotive examples: Cylinder head gaskets
gaskets, exhaust system
80-3648-01
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Bolts and Studs - Problems and potential solutions
Your problem
Potential Solutions
Potential Results
Fretting and seizure on
bolts made of austenitic
stainless steel.
• MOLYKOTE® D Assembly Paste
• MOLYKOTE® D-321 R AFC*
Reduced or no fretting nor
seizure during
g assembly,
y
damage-free /-reduced
disassembly.
Fretting and seizure on
bolts with galvanized
surface.
• MOLYKOTE® G-Rapid Plus Assembly
Paste
• MOLYKOTE® D-321 R AFC*
Reduced or no fretting or seizure
during assembly,
assembly damage-free/reduced disassembly.
Broken bolts and stripped
threads owing to scatter
of friction coefficient.
• MOLYKOTE® 1000 Thread Paste
• MOLYKOTE® 7405 AFC*
Constant pre-tensioning force of
fasteners from specified
tightening torque even after
repeated tightening.
Broken bolts due to
stress cracks on thread
surfaces.
• MOLYKOTE® P 37 Thread Paste
No detrimental influences on
metal surfaces
* AFC = Anti Friction Coating
80-3648-01
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Molykote® Specialty Lubricants
M h i lC
Mechanical
Component:
t Springs
S i
Springs
• The essential requirement of a spring is to absorb external
loads by elastic deformations
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Springs – General
• Lubrication Engineering:
– Frictional state: Boundary friction/mixed friction (inner friction
friction,
friction of guides, friction between several spring cups/friction at end
layers)
– Contact zone: all
– Friction factor: 0.03 – 0.2
– Main Type of Lubricants: Pastes and AFCs
• Failures:
–
–
–
–
Fretting and seizure on springs (fretting corrosion)
High
g frictional losses ((high
g frictional hysteresis)
y
)
Fracture of springs
Fretting corrosion
• Automotive examples: Suspensions, Window lifter
80-3648-01
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Springs - Problems and potential solutions
Your p
problem
Potential Solutions
MOLYKOTE® D
MOLYKOTE® DX
MOLYKOTE® X
MOLYKOTE® P 1500
Potential Results
Fretting and seizure on
springs,
•
•
•
•
High frictional losses
(broad hysteresis).
• MOLYKOTE® G-Rapid Plus
Assembly Paste
• MOLYKOTE® D 321 R AFC*
Smaller hysteresis
Fracture of springs
• MOLYKOTE® G-Rapid Plus
Assembly Paste
• MOLYKOTE® TP 42
Lower friction, Reduced failures
Fretting Corrosion
•
•
•
•
Reduced or no Fretting
corrosion anymore
MOLYKOTE® D
MOLYKOTE® DX
MOLYKOTE® TP 42
MOLYKOTE® 7409 AFC*
Reduced or no fretting nor
seizure during assembly
and long term lubrication
* AFC = Anti Friction Coating
80-3648-01
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Molykote® Specialty Lubricants
M h i lC
Mechanical
Component:
t Rolling
R lli Element
El
t Bearings
B
i
Rolling-element bearings
• Rolling element bearings are used for the precise guidance of
rotating
t ti parts
t especially
i ll shafts.
h ft Frictional
F i ti
l llosses are extremely
t
l
low as the bearing works with intermediate bodies. Main
g
movement is rolling
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Rolling-element bearings
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Rolling-element bearings – General
• Lubrication Engineering:
–
–
–
–
Frictional state: elastohydrodynamic friction
Friction factor: 0.001 – 0.01
Contact zone: point , line
Main Type of Lubricants: Greases (~90%)
• Failures:
– Short life due to high loads (solid lubricants)
– Short life due to extremely high temperatures (synthetic greases)
– Lubricant failure because of aggressive environmental influence
• Automotive examples: Wheel bearings, gear box bearings
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Rolling-element bearings – Problems and
potential solutions
Your problem
Potential Solutions
Potential Results
Short life due to high loads
• MOLYKOTE® BR2 Plus
• MOLYKOTE® Longterm 2 Plus
High load carrying
capacity securing
extended life
Short life due to extremely
high temperatures
•
•
•
•
•
Reduced or trouble-free
problems at high
temperatures.
Lubricant failure because
of aggressive
environmental influence
• MOLYKOTE® HP-870
• MOLYKOTE® 1292
• MOLYKOTE® 3451 bearing grease
MOLYKOTE® BG 20
MOLYKOTE® HP-870 (BG 87)
MOLYKOTE® FB 180 (good seals needed)
MOLYKOTE® 3451 (FS 3451)
MOLYKOTE® 7348 bearing grease
Greases resistant to most
solvents and many other
chemicals.
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Molykote® Specialty Lubricants
M h i lC
Mechanical
Component:
t Sliding-contact
Slidi
t tb
bearings
i
Sliding-contact bearings
• Sliding-contact bearings permit relative motion in shaft and
axle systems via sliding of shaft against bushing
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Sliding-contact bearings
a)
Brass
c) PE (annular groove)
e) PA 6.6 (annular groove)
b)
Bronze
d) POM (annular groove)
f), g) rolled composite bearings,
grease reservoirs (holes)
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Sliding-contact bearings
•
Lubrication Engineering:
– Frictional state: hydrodynamic friction (seldom mixed friction or dry running)
– Friction factor: 0.001 – 0.05 ((0.1 dry
y running)
g)
– Contact zone: area
– Main Type of Lubricants: Oils
•
Failures:
– Metal bearings
•
•
•
•
Stick-slip and damage during assembly and running-in
S ffi
Scuffing,
scoring,
i
hi
high
h wear.
Short life due to high loads
Short life and lubrication intervals owing to wet environment
– Plastic bearings
g
• Running-in damage, stick-slip, scuffing, seizure.
• High wear and short life owing to high temperatures or heavy loads. Swelling, shrinking,
stress cracks, change in strength characteristics due to inadequate lubricant.
•
Automotive examples: metal: engine bearings, Plastic: many small sliding-contact
bearings (i.e. pedal bearings)
80-3648-01
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Sliding-contact bearings: steel
Problems and potential solutions
Your problem
Potential Solutions
Potential Results
Stick-slip and damage
during assembly and
running-in
• MOLYKOTE® D-321 R AF-Coating
• MOLYKOTE® G-n plus
• MOLYKOTE® G-Rapid plus
assembly paste.
Solid lubricant film reduces or
prevents scoring and ensures
smooth and properly run-in
surfaces.
Scuffing, scoring, high
wear.
Short life due to high load
load.
• MOLYKOTE® BR 2 plus
• MOLYKOTE® Longterm 2 plus
bearing grease.
grease
High load carrying capacity
protects against metal-to-metal
contact and reduces wear
wear.
Short life and lubrication
intervals owing to wet
environment.
i
t
• MOLYKOTE® Longterm W2
• MOLYKOTE® Longterm 2 plus
b i grease
bearing
• MOLYKOTE® G-0102
Water resistant greases prevent
water entrance and longer by
th t service
that
i lifetime
lif ti
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Sliding-contact bearings: plastic
Problems and potential solutions
Your problem
Potential Solutions
Running-in damage, stick-slip,
scuffing, seizure
• MOLYKOTE® EM-30L
• MOLYKOTE® X5-6020
High wear
wear, stiff operation
operation, stress
cracks, swelling, shrinking,
effect on hardness due to
inadequate lubricant, short life
owing to high temperatures or
high loads
•
•
•
•
•
•
MOLYKOTE® PG 21
MOLYKOTE® EM-30L
MOLYKOTE® PG 54
MOLYKOTE® PG 75
MOLYKOTE® X5
X5-6020
6020
MOLYKOTE® YM-103
Potential Results
Specially developed
formulations ensure good to very
good compatibility with plastic
materials, reduces or minimize
the coefficient of friction,
increase the component life and
often reduce the running noise.
PG = Plastic Grease / EM = Electrical Molykote / YM = Yellow Molykote /
HP = High Performance / BG = Bearing Grease
EM-30L = PG 30L, X5-6020 =PG 602
80-3648-01
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Molykote® Specialty Lubricants
Mechanical
M
h i lC
Component:
t Sliding
Slidi
Guides
G id and
d
Linear Guide
5. Sliding Guides and Linear Guide Systems
• Sliding guides permit precise movements in machines and
units even under heavy loads.
loads Depending on the construction,
construction
loads can be absorbed perpendicularly to the guide way or in
transverse direction
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Sliding Guides
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Sliding Guides Systems
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Sliding Guides and Linear Guide Systems
• Lubrication Engineering:
–
–
–
–
Frictional state: old: mixed friction
friction, new: elasto
elasto-hydrodynamic
hydrodynamic friction
Friction Factor: 0.01 – 0.1
Contact zone: old: area, new: point
Main Type of Lubricants: Greases, oils
• Failures:
–
–
–
–
–
Stick-slip and damage during assembly and running-in
Scuffing, scoring, high wear.
Short life due to high load
Short life and lubrication intervals owing to wet environment
Fretting corrosion.
• Automotive examples: Seat adjustment
80-3648-01
©2011 all rights reserved – Dow Corning Corporation
Sliding guides – Problems and potential solutions
Your problem
Potential Solutions
Potential Results
Stick-slip and damage
during assembly and
running-in.
g
• Pre-treat with MOLYKOTE® G-n plus
or
MOLYKOTE® G-Rapid plus assemblyy
paste
Prevents stick-slip and scuffing,
reduces friction and wear
providing
g extended lubrication
intervals and service life time.
Scuffing, scoring, high
wear short life due to
wear,
high load.
• re-lubricate with MOLYKOTE® BR 2
plus or MOLYKOTE® Longterm 2 plus
bearing grease
Short life and lubrication
intervals owing to wet
environment.
• MOLYKOTE® Longterm W2
• MOLYKOTE® Longterm 2 plus
bearing grease
Protection against corrosion and
water wash-out.
Fretting corrosion.
• MOLYKOTE® DX grease paste
• MOLYKOTE® Longterm W2 bearing
grease.
Special solid lubricant
formulation in paste and grease
protects from fretting corrosion
80-3648-01
©2011 all rights reserved – Dow Corning Corporation
Sliding guides systems – Problems and
potential solutions
Your problem
Potential Solutions
Potential Results
High lubricant usage with
oil lubrication.
• Coating the guides with MOLYKOTE®
3402-C AF Coating or thin-film
lubrication with MOLYKOTE® DX
grease paste.
Replacement of oil lubrication by
dry or thin-film lubrication with
MOLYKOTE® products reduces
contamination
High wear due to
intermittent operation or
by small movement.
• Where travel distances are short and
operations few, one coat of
MOLYKOTE® 3402-C is enough. For
increased load, additional lubrication
with MOLYKOTE® DX and at high
load and speed, with Longterm 2 plus
bearing grease.
The solid lubricants contained in
the MOLYKOTE® products
reduce wear and allow
considerably longer roll-over
distances and running times.
MOLYKOTE® DX also largely
prevents fretting corrosion.
Insufficient accuracy as a
result of surface rolling
and wear.
80-3648-01
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Molykote® Specialty Lubricants
M h i lC
Mechanical
Component:
t Seal
S l
Seals
• A seal is used to act as barrier between spaces containing
different materials or different pressures
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Seals
Rubber case
Metal casing
Pressure side
Lip
Spiral
Spring
p g
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Seals
•
Lubrication Engineering:
– Frictional state: all states,
states gap seals (no contact possible)
– Friction factor: 0.001 up to values > 1
– Contact zone: line , area
– Main Type off Lubricants: Oils,
O
greases, fluid
f
that has to be sealed
•
Failures:
– Damage due to lubrication failure under aggressive environmental
influences.
– Shrinkage,
Sh i k
swelling
lli and
d stress
t
cracking
ki d
due tto llubricant
bi
t
incompatibility to the plastics involved. Stick-slip and damage during
assembly and running-in (O-ring assembly).
•
Automotive examples: Engine seals, cylinder head gasket
80-3648-01
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Seals: Problems and potential solutions
Your problem
Potential Solutions
Potential Results
Damage due to
lubrication failure under
aggressive environmental
influences
• MOLYKOTE® HP- 870
• MOLYKOTE® 3451, 3452 grease
Greases withstand chemical
attacks and hence protect seals
from dry running, which cuses
higher wear
Shrinkage, swelling and
stress cracking due to
lubricant incompatibility
• MOLYKOTE® EM-30L
• MOLYKOTE® HP- 870
• MOLYKOTE® 111 grease
Compatibility with most plastic
materials, therefore less or no
risk of fretting due to swelling,
less or no change in the strength
characteristics, little or no stress
cracking
80-3648-01
©2011 all rights reserved – Dow Corning Corporation
Molykote® Specialty Lubricants
M h i lC
Mechanical
Component:
t Bowden
B d C
Cables
bl
Bowden Cables
• Brief description: Bowden Cables are flexible connections
t
transmitting
itti axial
i l movementt
Grease
Inner member
Plastic tube,
HDPE, PP
Liner member
PA 6.6
Plastic mantle
Double metal
covering band
80-3648-01
©2011 all rights reserved – Dow Corning Corporation
Bowden Cables
• Lubrication Engineering:
–
–
–
–
Frictional
F
i ti
l state:
t t Mi
Mixed
d ffriction
i ti (h
(hydrodynamic
d d
i ffriction)
i ti )
Friction factor: 0.01 – 0.05
Contact zone: area
Main Type of Lubricants: Oils, greases
• Failures:
Fail res
– Damages due to lubrication failures (entrance of water)
– unfavourable routing
– Shrinkage, swelling and stress cracking due to lubricant incompatibility.
• A
Automotive
t
ti examples:
l
Gas
G cables,
bl
window
i d
lift
lifter cable,
bl h
handbrake
db k
cable
80-3648-01
©2011 all rights reserved – Dow Corning Corporation
Lubrication of Bowden control cables (1/2)
Hand Brake
MOLYKOTE® EM 30 L (very seldom) (PAO)
MOLYKOTE® 33 light (SI)
MOLYKOTE® G 56, G 72 (SI)
Clutch
MOLYKOTE® 33 Light / Med (SI)
MOLYKOTE® G 56 ((SI),
) G72 ((SI))
Gas Cable
MOLYKOTE® 33 Light /Med (SI)
MOLYKOTE® G 72 (SI)
MIN: Mineral oil
/ PAO: Polyalphaolefin / SI: Silicone Oil
80-3648-01
©2011 all rights reserved – Dow Corning Corporation
Lubrication of Bowden control cables (2/2)
Cables for seat
adjustment and safety
systems
MOLYKOTE® PG 21 (SI)
MOLYKOTE® PG 75 (MIN/PAO)
MOLYKOTE® EM 30L (PG-30L) (PAO)
General applications
window lifter, heating and
air-conditioning system,
system
engine bonnet
MOLYKOTE® PG 21 (SI)
Push-pull-system
Gear-shifting
MOLYKOTE® G 72 (SI)
MOLYKOTE® PG 75 (MIN/PAO)
MOLYKOTE® EM 30L (PG-30L) (PAO)
MOLYKOTE® G-5100 (new fluid grease) SI
PDMS, 1468 (SI, viscosities around 1000 cSt)
MIN: Mineral oil
/ PAO: Polyalphaolefin / SI: Silicone Oil
80-3648-01
©2011 all rights reserved – Dow Corning Corporation
Molykote® Specialty Lubricants
M h i lC
Mechanical
Component:
t Gears
G
Gears
• Gear wheels transmit torque via the engagement of suitably
arranged teeth without any slip
slip. Transmission of torque and
motion via gear wheels involves a reversal of the direction of
motion and a change of torque and speed
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Forms: Spur gears
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Gears
•
Lubrication Engineering:
– Frictional state: Boundary,
Boundary mixed friction
friction, hydrodynamic
– friction (all together on one gear tooth)
– Contact zone: line
– Efficiency: 95% for spur gears, ~ 50 (30-70)% for worm gears
– Main Type of Lubricants: Oils, fluid greases (pastes, AFCs for running-in, noises)
•
Failures:
– Steel gears:
• Running-in damage
• Wear, pittings
– Plastic gears:
• Running-in damage, stick-slip, scuffing, seizure
• High wear and short life owing to high temperatures or heavy loads. Swelling, shrinking,
stress cracks, change in strength characteristics due to inadequate lubricant
•
Automotive examples: Engine gear box, small actuators
80-3648-01
©2011 all rights reserved – Dow Corning Corporation
Steel gear wheels in enclosed gears
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©2011 all rights reserved – Dow Corning Corporation
Steel gear wheels in enclosed gears –
Problems and potential solutions
Your Problem
Potential Solutions
Potential Results
Running-in damage.
• Pre-treatment with MOLYKOTE® GRapid plus assembly paste
• MOLYKOTE® D-321 R AF Coating.
Solid lubricants enable
smoothing down of surface
asperities with less or without out
risk of fretting and scoring
resulting in very good mating
surfaces
Wear pittings
Wear,
• Add MOLYKOTE® M 55 plus
dispersion to gear oil
• For grease lubrication use
MOLYKOTE® Longterm 00
Prevents or reduces pitting
pitting,
protects against galling and
fretting
80-3648-01
©2011 all rights reserved – Dow Corning Corporation
Plastic gear wheels in enclosed gears
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©2011 all rights reserved – Dow Corning Corporation
Plastic gear wheels in enclosed gears –
Problems and potential solutions
Your Problem
Potential Solutions
Running-in damage, stick-slip,
scuffing, seizure
• MOLYKOTE® EM-30L
• MOLYKOTE® X5-6020 grease
High wear and short life owing
to high temperatures or heavy
loads. Swelling, shrinking,
stress
t
cracks,
k change
h
in
i
strength characteristics due to
inadequate lubricant.
•
•
•
•
•
•
MOLYKOTE® PG 21
MOLYKOTE® EM-30L
MOLYKOTE® PG 54
MOLYKOTE® PG 75
MOLYKOTE® X5-6020
MOLYKOTE® YM-103 grease
Potential Results
Specially developed formulations
ensure very good compatibility
with plastic materials, minimize
coefficient
ffi i t off friction,
f i ti
increase
i
component life and often reduce
running noise.
80-3648-01
©2011 all rights reserved – Dow Corning Corporation
Steel gear wheels in open gears
80-3648-01
©2011 all rights reserved – Dow Corning Corporation
Steel gear wheels in open gears – Problems
and olutions
Your Problem
High wear, pitting or corrosion
on gear wheels running at low to
medium speeds (up to 2 m/s),
Potential Solutions
S
• Pre-treat tooth flanks with
MOLYKOTE® G-n
G n plus or
MOLYKOTE® G-Rapid plus
assembly paste
• re
re-lubricate
lubricate with MOLYKOTE®
TP 42 grease paste,
MOLYKOTE® 165 LT or
MOLYKOTE® 1122 grease.
at high speeds (up to 6 m/s).
Potential Results
Solid lubricants enable
smoothing down of surface
asperities without or with less risk
of fretting and scoring resulting in
optimum mating surface finish.
Prevents or reduces pitting
pitting,
galling and fretting and protects
against wear caused by high
loads and difficult operating
conditions
• MOLYKOTE® 1122 grease.
80-3648-01
©2011 all rights reserved – Dow Corning Corporation
Molykote® Specialty Lubricants
M h i lC
Mechanical
Component:
t Chains
Ch i
Chains
• Chain Drives are used to transmit forces between parallel
shafts,
h ft whenever
h
spindle/shaft
i dl / h ft spacing
i iis ttoo hi
high
h or b
belt
lt
drives cannot be used
because of unfavourable
conditions (conveyor chains
are using
the same
principles).
80-3648-01
©2011 all rights reserved – Dow Corning Corporation
Chains
• Manual application
– Lubricant is applied using a brush or oil can
can, or by spray can or
hand spraying device, grease gun, or by dipping the chain in grease
containing a solvent, which then penetrates the critical wear areas
between pins and bushes, thereby producing adequate wetting of
the surfaces which are subject to wear. After about 30 minutes, the
solvent has evaporated and the chain is ready for use.
• Drip
Drip-feed
feed lubrication
– Using a drip-feed device, the chain lubricating oil is selectively
applied between the inner and outer plates of the chain links. This
place on the unloaded side of the drive. The q
quantity
y of oil
takes p
dependent on chain speed should be approx. 4 to 10 drops per
minute. The quantity of oil must be increased for temperatures in
excess of 60°C.
80-3648-01
©2011 all rights reserved – Dow Corning Corporation
Chains (Cont’d)
• Splash lubrication in oil bath
– Here the chain passes through an oil bath
bath. The chain is only
immersed as far as the middle of the link, in order to prevent
splash losses.
• Forced-feed
F
d f d circulatory
i
l t
lubrication
l b i ti
– The chain oil is distributed in a uniform flow over the entire chain
by means of pressurized central oil-lubrication. The returning oil
may be filtered and cooled, prior to being re-used.
• Oil/air lubrication (spray lubrication)
– This type of lubrication is economical
economical, but not environmentally
friendly. Environmental and health-at-work requirements can
only be met by exercising great care. A quantity of oil drops
appropriate to the lubricant requirement is atomized by a passing
stream of air and conveyed to the lubrication points. By virtue of
the fine distribution of droplets, they almost all reach the chain
linkss
80-3648-01
©2011 all rights reserved – Dow Corning Corporation
Chains
• Lubrication Engineering:
–
–
–
–
Frictional state: Mixed friction
friction, hydrodynamic friction
Contact zone: area
Efficiency: 95%: (Optimum)
Main Type of Lubricants: Oils, greases, pastes (adhesion improver)
• Failures:
F il
– High wear and short service life caused by high temperatures or
heavy load
– Insufficient lubrication because of high speeds
• Automotive examples: valve drive
80-3648-01
©2011 all rights reserved – Dow Corning Corporation
Chains: Problems and potential solutions
Your Problem
Potential Solutions
Potential Results
High
g wear and short
service life caused by high
temperatures or heavy load
• Apply
pp y MOLYKOTE® M 30 dispersion
p
q
lubrication up
p to +200 °C
Liquid
and dry lubrication by solid
lubricants up to +450 °C
• MOLYKOTE® CO 220 chain oil
• MOLYKOTE® S-15XX series
Temperature stable up to +250
°C, virtually no residues
• For grease lubrication use
MOLYKOTE®
O
O ® MKL-N chain grease
• MOLYKOTE® P 40
Strong adherence protects
lubricant from
f
spinning off
ff even
at higher speeds.
• in case of grease nipples
MOLYKOTE® 1122 chain grease
Long lasting lubrication up to
+160 °C
C with protection against
corrosion
Insufficient lubrication
because off high speeds
80-3648-01
©2011 all rights reserved – Dow Corning Corporation
Molykote® Specialty Lubricants
M h i lC
Mechanical
Component:
t Shaft-Hub
Sh ft H b Connections
C
ti
Shaft-Hub Connections
• Connections between shafts and hubs in a variety of forms like
splined shafts,
shafts shrink disks etc
etc.
80-3648-01
©2011 all rights reserved – Dow Corning Corporation
Shaft-Hub Connections: Shrink fit
80-3648-01
©2011 all rights reserved – Dow Corning Corporation
Shaft-Hub Connections
• Lubrication Engineering:
–
–
–
–
Frictional state: Mixed friction
friction, boundary friction
Contact zone: line (area)
Friction factor: 0.05 – 0.15 for press fittings
M i Type
Main
T
off Lubricants:
L bi
t G
Greases, pastes
t
• Failures:
– Stick-slip and damage during assembly and running-in
– High wear, stiff operation, fretting corrosion, increased tolerances
– Short
Sh t life
lif and
d lubrication
l b i ti iintervals
t
l owing
i tto wett environment
i
t
• Automotive examples: Clutch to gear box connection
connection, transaxles
80-3648-01
©2011 all rights reserved – Dow Corning Corporation
Shaft-Hub-Connections – Problems and
potential solutions
Your Problem
Potential Solutions
Potential Results
Stick-slip and damage
during assembly and
running-in
• MOLYKOTE® D-321 R AFC*
• MOLYKOTE® G-Rapid plus
• MOLYKOTE® G-n plus assembly
paste
p
Pre-treatment with MOLYKOTE®
AFC or assembly paste ensures
very good run-in.
High wear, stiff operation,
fretting corrosion,
increased tolerances
• MOLYKOTE® BR 2 plus
• MOLYKOTE® Longterm 2 plus
bearing grease
• MOLYKOTE® P 40
Re-lubrification with
MOLYKOTE® bearing grease
provides protection against wear
and fretting corrosion.
corrosion
Short life and lubrication
intervals owing to wet
environment
• MOLYKOTE® Longterm W2 or
MOLYKOTE® Longterm 2 plus
bearing grease.
Good protection against water
80-3648-01
©2011 all rights reserved – Dow Corning Corporation
Molykote® Specialty Lubricants
M h i lC
Mechanical
Component:
t Clutches
Cl t h
Clutches
• Clutches and couplings are used to connect two shafts
80-3648-01
©2011 all rights reserved – Dow Corning Corporation
Clutches
• Lubrication Engineering:
–
–
–
–
Frictional state: Dry friction
friction, boundary friction
friction, mixed friction
Contact zone: all
Friction factor: 0.1-0.3
M i T
Main
Type off Lubricants:
L bi
t greases, oils,
il iincorporated
t d solid
lid llubricants
bi
t
• Failures:
– High wear of mechanical components
– Fretting on splined shaft
– Shrinkage,
Sh i k
swelling
lli and
d stress
t
cracking
ki d
due tto llubricant
bi
t iincompatibility
tibilit
especially in hydraulic clutch engagement
• Automotive examples: Engine clutch
80-3648-01
©2011 all rights reserved – Dow Corning Corporation
Clutches – Problems and Solutions
Your Problem
Potential Solutions
Potential Results
High wear
• MOLYKOTE G-Rapid plus
• MOLYKOTE Longterm 2 plus
Pre-treatment with assembly paste
ensures very good running
running-in.
in ReRe
lubrication with grease
Fretting
g corrosion
• MOLYKOTE BR 2 plus,
• MOLYKOTE G-n plus,
• MOLYKOTE P 40
Re-lubrification with MOLYKOTE
greases or paste provides protection
against wear and fretting corrosion
especially for splined shafts.
Shrinkage, swelling and
stress cracking due to
lubricant incompatibility
• MOLYKOTE G-807
MOLYKOTE G-807 in use in hydraulic
clutch engagement systems
80-3648-01
©2011 all rights reserved – Dow Corning Corporation
Molykote® Specialty Lubricants
M h i lC
Mechanical
Component:
t Ball
B ll Joints
J i t
Ball Joints
• Joints are used as a economical and reliable transmission
componentt off forces
f
and
d torques
t
i.e.
i ball
b ll and
d socket
k t joints,
j i t
universal joint, constant velocity joints
Shaft
Bellow
Plastic
bushing
Labyrinth sealing of bellow
Ball
80-3648-01
©2011 all rights reserved – Dow Corning Corporation
Ball Joints
• Lubrication Engineering:
–
–
–
–
Frictional state: Mixed friction
friction, hydrodynamic friction
Contact zone: area
Friction factor: 0.01 – 0.1
M i Type
Main
T
off Lubricants:
L bi
t G
Greases
• Failures:
– Damage due to high loads, water entrance and hereby corrosion
– Shrinkage, swelling and stress cracking due to lubricant incompatibility.
– Stick-slip
S
and damage during assembly and running-in
• Automotive examples: Ball joints for suspension and steering rack
80-3648-01
©2011 all rights reserved – Dow Corning Corporation
Ball Joints: Problems and potential solutions
Your Problem
Potential Solutions
Potential Results
Damage due to high loads
loads,
water entrance and hereby
corrosion
• MOLYKOTE® G 72 for plastic
bushings
• MOLYKOTE® Longterm 2/78G for
plastic and steel bushings
Good load carrying capacities
capacities,
very good resistant to water
Shrinkage, swelling and stress
cracking due to lubricant
incompatibility
• MOLYKOTE® G 72
Good plastic compatibility
Stick-slip and damage during
assembly and running-in
• MOLYKOTE® G-Rapid plus
Easy to assemble
80-3648-01
©2011 all rights reserved – Dow Corning Corporation
Molykote® Specialty Lubricants
M h i lC
Mechanical
Component:
t Press-fit
P
fit joints
j i t
Press-fit joints
80-3648-01
©2011 all rights reserved – Dow Corning Corporation
Press fit Joints – Problems and potential solutions
Your Problem
Difficult and time consuming
assembly because of stick-slip.
Scuffing, scoring or other
component damage during
press fitting
press-fitting.
Potential Solutions
Pre-treat
Pre
treat contact surfaces with
• MOLYKOTE® D
• MOLYKOTE® G-n plus
• MOLYKOTE® G-Rapid plus
assembly paste.
paste
Potential Results
Smooth press-fitting
press fitting and easy
dismantling - even after long
service time.
80-3648-01
©2011 all rights reserved – Dow Corning Corporation
Molykote® Specialty Lubricants
M i t
Maintenance
and
d Repair
R
i
Maintenance and Repair
80-3648-01
©2011 all rights reserved – Dow Corning Corporation
Maintenance and Repair - Problems and
potential solutions
Y
Your
Problem
P bl
P
Potential
i l Solutions
S l i
P
Potential
i l Results
R
l
Difficult dismantling
owing to corrosion and
rust
• Spray MOLYKOTE® Multigliss or
MOLYKOTE® Supergliss onto the
components
Penetrates and loosens rust
resulting normally in non
nondestructive dismantling
Contaminated
components.
• MOLYKOTE® Metal Cleaner/Brake
Cleaner
Quick and effective degreasing
Stick-slip and damage
during assembly and
running-in
• MOLYKOTE® G-n plus or
MOLYKOTE® G-Rapid plus
assembly paste
Solid lubricant film reduces or
prevents scoring and ensures
smooth and properly run-in surfaces
Corroded components
due to corrosive
environment
• MOLYKOTE® Copper paste Cu7439 plus MOLYKOTE® P 40
Provides both long term lubrication
and excellent corrosion protection
Seized or broken bolted
connections
• MOLYKOTE® thread pastes (see
components, Bolts, studs)
Good protection against corrosion
80-3648-01
©2011 all rights reserved – Dow Corning Corporation