Servicing torque motors is essential to ensure optimal performance in applications where high precision and constant torque are required. These motors are often used in industrial applications for direct drive without gearboxes and offer high efficiency and precision. Torque motors are found, for example, in CNC rotary table centres. Regular maintenance and servicing can prevent costly breakdowns and ensure longer motor life.

Steps in servicing torque motors

  1. Diagnostics and screening

  • Torque and speed measurement: checking that the engine is delivering the intended torque and running at the correct speed.
  • Vibration analysis: unusual vibrations are often a sign of problems with bearings or unbalanced rotating parts.
  • Electrical parameter verification: winding resistance measurement, insulation resistance measurement, insulation resistance measurement on power cables, temperature sensor diagnostics

  1. Inspection of bearings, moving parts and cooling system

  • Inspecting and replacing bearings: worn bearings are often the cause of vibration, noise and excessive heating. Replacing bearings is essential to keep the engine running smoothly.
  • Lubrication check: ensure that all moving parts are properly lubricated, as insufficient lubrication leads to wear and damage.
  • If the cooling medium is used incorrectly, the cooling system may become clogged due to rust or other impurities and the torque motor will start to

  1. Electrical inspection

  • Winding testing: measuring the resistance of windings to detect insulation damage and checking for possible inter-phase contacts.
  • Checking the temperature sensors: It is necessary to ensure that the temperature sensors , as they prevent the engine from overheating.

  1. Balancing the rotor

  • Balancing the rotor: it is important that the rotor is correctly balanced to reduce vibration and bearing wear for smooth engine operation.

  1. Cleaning and dirt removal

  • Removing dust and particles: torque motors must be kept clean as dust and dirt can cause overheating or damage internal components.
  • Inspection of cooling systems:If the engine is cooled by a coolant, the cooling system must be inspected and cleaned to ensure proper cooling.

  1. Testing magnets

  • Magnet test: measuring the magnetic field strength of the magnets ensures the motor has the correct torque and is linked to positioning accuracy and continuous motion. The test shall be carried out prior to the actual servicing and shall form the basis for action and remediation.

  1. Testing after repair

  • Vibration and thermal tests: after the service, additional vibration and temperature tests are carried out to ensure that the engine operates correctly under realistic conditions.
  • Long-term testing: to ensure the reliability and durability of the engine, it is recommended to carry out long-term running tests.

Signs that a torque motor needs servicing

  • Unusual sounds or vibrations.
  • Increased temperature during operation.
  • Reduced performance or accuracy.
  • Uneven operation or sudden loss of power.
  • Positioning errors.

Regular maintenance

It is recommended that torque motors are serviced regularly, especially when used under high loads. Preventive maintenance reduces the risk of failure and prolongs the life of the motor. The best time for preventive servicing is at the time of replacement or servicing of the machine where the torque motor is installed.