Maintenance

Service > Download > Maintenance

Reliable long service life

If spring-applied brakes are expected to function optimally and safely, they must be checked and maintained at regular intervals. INTORQ spring-applied brakes are wear-resistant and designed for long maintenance intervals. Friction linings, teeth between brake rotor and hub, as well as the brake mechanism are nevertheless subject to physical wear depending on their functionality.

In order to speed up inspection and maintenance work, these steps can be carried out together with other facility maintenance work. This work can often be carried out much faster if the brakes are easily accessible. This must be considered when installing the drives in the facility.  

Why wait?

Malfunctions, breakdowns or facility damage can occur when regular maintenance is not carried out. To optimize maintenance, every application requires a maintenance strategy adapted to the operating conditions and loads of the particular brake. (The QR code on our brakes takes you directly to the correct documents, so that you can read the operating instructions to order spare parts.)

You can find an overview of maintenance intervals and procedures for the INTORQ spring-applied brakes here:


Wartungsintervalle & -arbeiten
Model series

Time interval

Maintenance procedure

BFK457-XX
BFK460-XX
BFK461-XX
BFK458-XXX
BFK468-XXX

For operating brakes:

  • according to the service life calculation,
  • or else every six months,
  • after 4000 operating hours at the latest

Inspections with assembled brake:

  • Check release function and control
  • Measure the air gap (adjust if required)
  • Measure the rotor thickness (replace rotor if required)
  • Thermal damage of armature plate or flange (dark-blue tarnishing)

Inspections after the brake has been removed:

  • Check the play of the rotor gear teeth (replace worn-out rotors)
  • Check for breaking out of the torque support at the sleeve bolts and the armature plate
  • Check the springs for damage
  • Check armature plate and flange
    – Flatness for sizes BG06-BG12 < 0.06 mm
    – Flatness for sizes BG14-BG25 < 0.1 mm
    – Max. run-in depth = rated air gap of size

Brakes with defective armature plates, threaded sleeves, springs or flanges must be replaced completely.

For holding brakes with emergency stop:

  • at least every 2 years
  • after 1 million cycles at the latest
BFK458-XXL
For operating brakes:
  • according to the service life calculation,
  • or else every six months,
  • after 4000 operating hours at the latest
For holding brakes with emergency stop:
  • at least every 2 years
  • after 10 million cycles at the latest
  • plan shorter intervals for frequent emergency stops.
BFK418-XXR
For holding brakes with emergency stop: 
  • at least every 2 years
  • after 5 million cycles at the latest
  • Plan shorter intervals for frequent emergency stops.
Inspecting the brake installed in the motor:  
  • Check release function and control
  • The wear can only be checked by measuring the release current (current value?)
A worn BFK418 must be completely replaced; no repair is possible.
The following applies to all inspection and maintenance work:
  • Maintenance work must be carried out as described in the corresponding operating instructions.
  • Contamination by oils and greases should be removed using brake cleaner, or the brake should be replaced after determining the cause. Dirt and particles in the air gap between the stator and the armature plate endanger the functionality!
  • After replacing the rotor, the original braking torque will not be reached until the run-in operation for the friction surfaces has been completed. After replacing the rotor, the run-in armature plates and the flanges have an increased initial rate of wear. Adjust the air gap earlier if necessary.

Calculating the maintenance intervals

The maintenance intervals for working brakes are primarily determined by their load. All causes of wear and the influencing factors are included in the calculation. For brakes with a low load (e.g. holding brakes with emergency stop), we recommend a regular inspection. The standard inspection intervals can be found in the corresponding operating instructions.

We have put together here an overview of the normal causes of wear for individual components, as well as the influencing factors and effects.

Wartungsintervalle berechnen

Component

Causes for wear

Influencing factors

Effect

Friction lining
  • Braking during operation
  • Emergency stops
  • Overlapping wear during start and stop of drive
  • Active braking via the drive motor with support of brake (quick stop)
  • Starting wear in case of motor mounting position with vertical shaft, even when the brake is not applied
  • Friction work
  • Number of start/stop cycles
Wear of friction lining
Armature plate and flange Rubbing and friction of the brake lining Friction work Armature plate and flange are run in
Gear teeth of brake rotor Relative movements and shocks between brake rotor and brake shaft Number of start/stop cycles Wear of gear teeth (primarily on the rotor side)
Armature plate support Load reversals and jerks in the backlash between armature plate, adjustment tubes and guide pins Number of start/stop cycles, level of braking torque Breaking of armature plate, sleeve bolts and pins
Springs Axial load cycle and shear stress of springs through radial backlash on reversal of armature plate Number of switching operations of brake Reduced spring force or fatigue failure
  • The influential factors must be quantified so that the service life of the rotor and brake can be calculated and so that the maintenance intervals can be specified accurately. The most important factors in this context are the applied friction work, the initial speed of rotation of braking and the operating frequency.
  • If several of the causes of wear occur in an application at the same time, the influencing factors should be added together when the amount of wear is calculated.