Maintenance and repair
Kendrion INTORQ | BA 14.0224 | 02/2021
37
8
Maintenance and repair
8.1
Wear of spring-applied brakes
WARNING
Braking torque reduction
The system must
not
be allowed to continue operations after the maximum air gap s
Lmax
has been exceeded. Exceeding the maximum air gap can cause a major reduction in the
braking torque!
The table below shows the different causes of wear and their impact on the components of the spring-ap-
plied brake. The influencing factors must be quantified in order to calculate the service life and prescribed
maintenance intervals of the rotor and brake accurately. The most important factors in this context are the
applied friction work, the initial speed of rotation before braking and the operating frequency. If several of
the causes of friction lining wear occur in an application at the same time, the effects should be added to-
gether when the amount of wear is calculated.
Component
Cause
Effect
Influencing factors
Rotor
Service braking
Wear of the friction lining
Friction work
Emergency stops
Overlapping wear during start and
stop of drive
Active braking via the drive motor
with support of brake (quick stop)
Start-up wear in case of motor
mounting position with vertical
shaft, even when the brake is not
applied
Number of start/stop cycles
Armature plate and
counter friction sur-
face
Rubbing and friction of the brake
lining
Run-in of armature plate and
counter friction surface
Friction work
Gear teeth of brake
rotor
Relative movements and shocks
between brake rotor and brake
shaft
Wear of gear teeth (primarily
on the rotor side)
Number of start/stop cycles
Armature plate sup-
port
Load reversals and shocks in
backlash during reversals be-
tween armature plate and arma-
ture plate guide
Running in the armature plate
into the armature plate guide
Number of start/stop cycles,
braking torque
Springs
Axial load cycle and shear stress
of springs through radial backlash
on reversal of armature plate
Reduced spring force or fa-
tigue failure
Number of switching opera-
tions of brake
Tab. 7:
Causes for wear