Balancing of Rotating Machinery - CAT III & CAT IV

This course covers single-plane balancing techniques for both rigid and flexible rotors. It includes both field balancing and shop (balancing machine) balancing. Topics such as pre-balance checks, influence coefficients and case histories are included.  This course partial preparation for the Vibration Analyst Category III and IV, and Balancing Specialist Certification Exams.

Dec 7-11, 2020

San Diego, CA

Balancing of Rotating Machinery


This course covers single and basic two-plane balancing techniques. It includes both field balancing and shop (balancing machine) balancing. Topics included are pre-balance checks, influence coefficients, balance quality and tolerances, residual unbalance testing and case histories. It is partial preparation for the Vibration Analyst Category III and IV, and Balancing Specialist Certification Exams.


BILL PRYOR is the Technical Director for PDM Solutions, Inc. He has over 35 years experience in the vibration analysis and rotating machinery field. Field experiences includes machinery troubleshooting, balancing, alignment, structural analysis, transient testing, and the commissioning of rotating equipment. In addition, he has assisted in the establishment of many PDM programs throughout the industry. Before joining PDMS, Pryor was with PSEG Power from 1986 to 1999 as a Senior Test Engineer and then moved to the Bently Nevada Corporation from 1977 to 1986. He has an AAS in Product and Machine Design from the State University of New York at Alfred. He sits on the Board of Directors at the Vibration Institute. Before joining the Institute’s training department he was actively involved in the Vibration Institute’s certification committee. Pryor is certified Vibration Analyst Category IV.

Course Materials

Course PowerPoint follow-along deck
Course notes
Workbook containing examples, workshop problems and the Body of Knowledge found in Vibration Institute Guideline No. 1

Requirement for qualification and assessment of balancing personnel
Training course examination study guide
Calculator, ruler and balancing tools
Certificate of completion (3.7 CEUs)

Course Agenda

Monday, Noon – 5:00 p.m.
Tuesday – Friday, 8:00 a.m. – 5:00 p.m.
Balancing exam – Saturday, 8:00 a.m. – 12:00 p.m.

Registration Fees

$1,995 USD Nonmember ($1,900 VI Members)
$100 expidited materials fee for registrations received within 1 week of course starting.

Course Content

Basic Aspects of Machine Balancing
Purpose, mass unbalance force and causes, rotor classification, techniques, equipment, pre-balancing checks, critical speeds, trial weight selection/placement, and pitfalls.

Single-Plane Balancing Techniques
Vector and four-run methods, critical speeds, modes, heavy spot high-spot relationship, balance sensitivity, phase lag, trial weight selection, weight splitting, criteria and standards, one-shot method.

Workshop I: Balancing Topics
Class exercises on basic principles.

Workshop II: Single-Plane Balancing
Hands-on exercises using a rotor kit, vector method, single-plane balancing; registrants can bring an instrument or use the Institute’s equipment.

Two-Plane Balancing Techniques
Basic Influence coefficient and static/couple methods, one-shot balancing, two-plane balancing, strategy, and procedures.

Workshop III: Two-Plane Balancing
Static-couple method, class exercises.

Workshop IV: Two-Plane Balancing
Influence co-efficient method, class exercises.

Turbine/Generator Balancing
Procedures, static/couple method, influence coefficient method, plane/sensor selections, strategy for least runs.

Roll Balancing
Weight placement, critical speeds, bow effects.

Fan Balancing
Balancing techniques (single- and two-plane), overhung fans, balance sensitivity, critical speeds, case histories.

Shop Balancing Techniques
Balance machine procedures and calibration.

Balancing Case Histories
Balancing in the field, procedures, strategies, and pitfalls.

Course Review

Training Examination on Course Content (1.5 hours)

Training Examination Review

Get Certified

Certification Exams are offered:

  1. The day AFTER VI training courses 
  2. Anytime at VI offices
  3. At a USA location near you with a pre-approved VI proctor
  4. Through our International Representatives


  1. Register for a course and exam
  2. Register for just the exam (if you already have the training requirement, or are getting training elsewhere)
  3. Find a USA proctor by contacting us
  4. Contact an International Representative in your country

The cancellation of and transfer to a training course within the same calendar year will be honored, provided that written notification is received by the Institute office via e-mail or mail no later than ten (10) business days before the first day of the scheduled course. If registration for a training course is cancelled without transfer to another course within the same calendar year, a $250 cancellation fee will be assessed. A $500 administrative fee will be charged for cancellations received less than ten (10) days from the start date of the registered training course. Additional cancellation fees will be applied for exam cancellations. Absentees for the course will not receive a refund. Please contact the Vibration Institute staff directly regarding discounts for multiple registrations from the same organization.