ISO 21940-14:2012/Amd 1:2022

Overview

ISO 21940-14:2012/Amd 1:2022 is an amendment to the international standard focusing on mechanical vibration and rotor balancing. Specifically, it updates Part 14 of the ISO 21940 series, which covers procedures for assessing balance errors in rotating machinery. This amendment refines existing evaluation methodologies to enhance accuracy and clarity in determining rotor balance quality.

Maintained by ISO Technical Committee ISO/TC 108, Subcommittee SC 2, this document ensures harmonization of testing methods related to mechanical vibrations and rotor balancing for machines, vehicles, and structures.

Key Topics

• Rotor Balancing Procedures
  The amendment revises procedures for assessing rotor balance errors, emphasizing the correct summation of uncorrected errors assuming they occur in the same angular direction.

• Measurement Error Accounting
  The updated guidance stresses the importance of incorporating measurement errors into balance quality verification, in accordance with ISO 21940-11:2016 Clause 10. This ensures that tolerance assessments consider all potential sources of error.

• Inter-standard References
  ISO 21940-14:2012/Amd 1:2022 references related parts of the ISO 21940 series, including:

  • ISO 21940-11:2016 (Procedures and tolerances for rotors with rigid behaviour)
  • Replacement of older documents by ISO 21940-2, ISO 21940-11, and ISO 21940-12 parts for consistency.

• Balance Quality Verification
  The amendment clarifies that acceptance of rotor unbalance states involves mutual agreement between parties, highlighting that standardization does not dictate these acceptance criteria.

Applications

ISO 21940-14:2012/Amd 1:2022 is essential for industries relying on precision rotor balancing to minimize mechanical vibration and enhance equipment reliability. Practical applications include:

• Rotating Machinery Maintenance
  Use in monitoring and correcting rotors in turbines, motors, compressors, and fans to prevent vibration-related failures.

• Manufacturing Quality Control
  Ensures that rotor components meet balance tolerances during production, improving product quality and operational safety.

• Automotive and Aerospace Engineering
  Critical for balancing rotating parts such as engine components, propellers, and driveshafts to maintain smooth operation and reduce noise and wear.

• Condition Monitoring and Predictive Maintenance
  Supports assessment protocols for operational rotors, aiding in early detection of imbalance-related issues.

By adhering to the procedures set forth in this amendment, engineers and technicians can enhance the accuracy of balance error assessments, ultimately extending machinery life cycles and reducing maintenance costs.

Related Standards

This amendment integrates closely with several parts of the ISO 21940 series and other mechanical vibration standards:

• ISO 21940-11:2016 – Procedures and tolerances for rotors with rigid behaviour, critical for applying the measurement error considerations introduced in this amendment.

• ISO 21940-2 – Replacing earlier withdrawn documents, it defines terms and parameters fundamental to rotor balancing.

• ISO 21940-12 – Addresses balancing procedures for rotors exhibiting flexible behavior.

• General Standards on Mechanical Vibration – Other ISO/TC 108 standards covering vibration measurement and evaluation complement the rotor balancing series for comprehensive assessment and diagnostics.

Using this amendment in conjunction with related standards ensures a systematic and standardized approach to rotor vibration analysis and balancing across industries.

For detailed guidance, practitioners should consult the full ISO 21940-14:2012/Amd 1:2022 document and coordinate with their national standards body for implementation and compliance advice. This amendment aids in maintaining global consistency and reliability in rotor balancing assessments, supporting industrial efficiency and equipment safety.