Correction Methods in Dynamic Balancing

Once a dynamic balancing machine detects the magnitude and angular location of an unbalance, the excess mass must be removed or counterweighted to bring the rotor within acceptable ISO standards.

Here are the primary correction methods used in industrial manufacturing:

1. Material Removal Methods 

These methods involve removing material from the "heavy spot" of the rotor to restore balance. They are clean, permanent, and widely used in automated or high-speed production lines.

• Drilling :

  • How it works: A drilling machine or automated drill unit removes material by drilling axial or radial holes into a designated correction plane.

  • Best for: Rotors like flywheels, brake discs, pulleys, and fan hubs.

• Milling :

  • How it works: A CNC milling cutter removes a specific segment or slot of material from the edge or face of the rotor.

  • Best for: Clutch pressure plates, heavy industrial armatures, and large disc-shaped components where precise pocket cutting is needed.

• Grinding / Turning :

  • How it works: Material is shaved or ground away along the outer diameter or face of the component.

  • Best for: Cylindrical rotors or shafts where uniform surface reduction is feasible.

2. Material Addition Methods 

These methods involve adding mass directly opposite the heavy spot (at the "light spot"). They are typically used when the parent material cannot be safely drilled or cut into.

• Welding :

  • How it works: Balancing weights (such as steel plates, clips, or slugs) are welded onto the rotor.

  • Best for: Heavy-duty industrial components like large fan impellers, blower wheels, and drive shaft tubes. Requires careful weld integrity to withstand high centrifugal stresses.

• Adding Counterweights / Balance Clips :

  • How it works: Pre-manufactured weights are screwed, bolted, riveted, or clipped onto designated slots or rims.

  • Best for: Automotive wheels (clip-on weights), cooling fans, and certain types of electric motor rotors.

• Balancing Glue / Resin :

  • How it works: Specialized epoxy or balancing paste is applied and cured on the component.

  • Best for: Small electric armatures or lightweight consumer appliance rotors where mechanical fastening is impractical.

3. Specialized / Automated Correction

• Laser or Plasma Cutting: Used in high-precision, automated balancing lines to instantly vaporize or cut away small amounts of material without mechanical stress.

• Automatic Balancing Machines: Many modern industrial machines integrate the correction step directly into the cycle (e.g., auto-drilling or auto-welding integrated with the measuring unit), significantly reducing cycle times for mass production.