Project Description

Large Servo Motor Repair & Plastic Industry Servos

Whether your equipment is injection molds, single screw extruders or maximum impact feed screws these high-powered machines were traditionally all powered by hydraulics. However, the use of large servo motors to provide torque is growing in this type of machinery. Although servo motors are not new to automated manufacturing, they have been used primarily in machine tooling. Newer styled AC servo motors in particular have terrific torque characteristics at all speeds. So, what kind of servo motor design could replace a hydraulic injection mold machine? A really big one!

Large servo motors are all about torque. Instead of relying on a normal electric motor and a gearbox, these servo motors provide a more efficient power source. Plastics motors utilize strong magnets to optimize torque at low speeds, rather than to limit current at high speeds. In a plastics machine servo motor, neodymium rare earth magnets are utilized to get the most force out of each ampere. , , Baumuller and all offer large servo motors of this style. They feature large frames and connectors to handle the physical demands of the application and the current.

Servotech has all of the advanced capabilities, knowledge and industry connections to repair large servo motors and keep them injecting and extruding.

Large Servo Motor Repair
Simple machines – use of a long large threaded rod enables technicians to overcome the tremendous force of the magnets to remove this from its stator – The rotor needs machine work both on the coupling surface and bearing journal.
Large Servo Motor Repair
After machining, chroming and grinding – a time intensive process – the rotor is safely back inside the stator and ready for duty on this Fanuc servo motor.
Large Servo Motor Repair
An example of a rotor from a plastics servo motor whose failure was so severe the integrity of the magnets and banding material have been compromised.
Large Servo Motor Repair
After epoxied magnets, re-banding and re-magnetizing, the rotor has been restored to operate in this Yaskawa servo motor.

Heavy Duty Servo Repair Procedures – Excessive load causes shaft damage and bearing failure in large servo motors. Servotech can:

  • Weld and Turn – Chrome and grind failed bearing journals and tapered output shafts
  • Bore and bush ruined servo motor bearing fits
  • Machine new keyways into servo output shafts
  • Machine a second keyway 180 degrees from original (why pull a motor when all you’d have to do is rotate the coupling?)
  • Reband rotors that have rubbed, or deteriorated from heat
  • Re-epoxy and re-magnetize servo motor magnets
  • Obtain AC servo motor encoders directly from the manufacturer – we have an established relationship with Fanuc and are and .
  • Create servo motors out of spare parts – the benefit of having a spare servo motor on your shelf cannot be overstated.
Large Servo Motor Repair
Bright shiny copper is visible – this winding got so hot it melted. The re-cooled bare copper shines through where as normal windings are coated in a varnish that gives them a dull color.
Large Servo Motor Repair
A beautifully rewound AC servo motor winding – a tough job on the large servo motors that are often used in the plastics industry.
Large Servo Motor Repair
Large servo motors have many small components, like motor leads, feedback connections and fans. Servotech experts correctly configure large servo motor wiring.
Large Servo Motor Repair
A job well done, this AC Fanuc servo motor is completely re-assembled, aligned, and tests great!