Practical Field Balancing


  • 3-Day Class
  • Optional Certification Testing is available in the afternoon on the last day of the course.

Primary Objectives

  1. Instruct how to confirm that unbalance is one of the dominant problems (using straightforward spectral & phase analysis).
  2. Use Hands-on Demonstrations to teach how to properly balance a variety of machinery using both graphical methods and data collectors with balancing programs.
  3. Teach single-plane and two-plane field balancing techniques using a variety of today’s data collectors.
  4. Teach special balancing techniques required on overhung rotors.
  5. Provide and clearly explain today’s balancing tolerances.


  • Previous vibration analysis experience is recommended but is not required prior to attending this seminar.
  • Previous field balancing experience is helpful but is not required prior to attending this seminar.
  • General familiarity with using today’s data collectors or portable balancing instruments is also beneficial (a variety of such instruments will be demonstrated during interactive class exercises).
  • Good math skills and the ability to use and interpret graphs and tabular information will be beneficial in order to maximize understanding.

Seminar Agenda

Definition of Unbalance

  • Static Unbalance
  • Couple Unbalance
  • Quasi-Static Unbalance
  • Dynamic Unbalance

Types of Unbalance:

Rigid Versus Flexible Rotors

  • Assembly Errors
  • Casting Blow Holes
  • Fabrication Tolerance Problems
  • Key Length Problems
  • Rotational Distortion
  • Deposit Buildup or Erosion
  • Unsymmetrical Design

Causes of Unbalance:

Technical Associates: Practical Field Balancing Training; gears

How to Ensure the Dominant Problem is Unbalance:

  • Review of Typical Spectra and Phase Behaviors For Common Machinery Problems
    • Mass Unbalance
    • Eccentric Rotor
    • Bent Shaft
    • Misalignment
    • Resonance
    • Mechanical Looseness/Weakness
  • Summary of Phase Relationships For Various Machinery Problems
  • Summary of Normal Unbalance Symptoms

Field Balancing Techniques:

  • Recommended Trial Weight Size and Placement
  • Single-Plane Balancing Using a Portable Data Collector
  • Two-Plane Balancing Using a Portable Data Collector
  • Balancing Overhung Rotors
    • By Classic Single-Plane Static-Couple Method
    • By Classic Two-Plane Static-Couple Method
  • Splitting Balance Correction Weights
  • Combining Balance Correction Weights
  • Effect of Angular Measurement Errors On Potential Unbalance Reduction
  • Commonly Encountered Balancing Problems

Recommended Vibration and Balance Tolerances:

  • Vibration Tolerances
    • Overall Vibration Specifications
    • Spectral Alarm Band Specifications
  • Balance Tolerances on Allowable Residual Unbalance
    • ISO 1940 Balance Quality Grades
    • How to Determine Residual Unbalance Remaining in a Rotor After Balancing
    • API Balance Tolerances

Hands-On Instruction:

  • Hands-On Demonstration of Single-Plane Balancing
    • Using a Portable Data Collector
  • Hands-On Demonstration of Two-Plane Balancing
    • Using a Portable Data Collector
  • Hands-On Demonstration of Balancing Overhung Rotors
    • Using Classic Single-Plane Static-Couple Method
    • Using Classic Two-Plane Static-Couple Method
  • Demonstration of Splitting Balance Correction Weights
  • Demonstration of Combining Balance Correction Weights

Balancing Machines - Soft Versus Hard Bearing

Seminar Fee: $1095     (will increase to $1195 starting January 1, 2018)

A $100 DISCOUNT will be given for payments at least 60 DAYS prior to the seminar start date.

Seminar Fees include textbook, breaks and lunches.





1230 West Morehead Street, Suite 400

Charlotte, North Carolina  28208