Overview
ISO 6545:1992 - "Acceptance conditions for gear hobbing machines - Testing of the accuracy" defines how to verify the geometric and kinematic accuracy of general-purpose and normal-accuracy gear hobbing machines (vertical or horizontal spindle). The standard specifies geometrical tests, practical finishing-cut tests and kinematic checks (accuracy of transmission of motion), gives machine-element terminology, and references measurement and installation practices in ISO 230‑1. Dimensions and permissible deviations are given in millimetres and inches.
Key topics and requirements
- Scope of testing
- Geometrical tests for sub-assemblies (work-table, work-steady, axial/tangential slides, spindles).
- Practical tests carried out with finishing cuts (not roughing) to reflect real machining accuracy.
- Kinematic tests to assess transmission accuracy (angular, tangential and axial transmission deviations).
- Measurement rules
- Test setup, warm-up and instrument mounting follow ISO 230‑1 guidance.
- Results and permissible deviations are expressed in mm/in; rounding rules and minimum tolerance (e.g., lowest tolerance value guidance) are specified.
- Instruments and permissible deviations for individual tests are referenced back to ISO 230‑1 acceptance code.
- Terminology and symbols
- Definitions for main machine elements (hob, work-arbor, work-table, work-steady, slides) and symbols for deviations and parameters (pitch, helix, profile, transmission deviations).
- Multilingual term list (official ISO languages + German terms provided for information).
- Test selection and sequencing
- The sequence of geometrical tests in the standard follows machine sub-assemblies but may be reordered for practical instrument mounting.
- Users and manufacturers agree which tests to perform; not all tests are mandatory for every inspection.
Practical applications and users
- Used for factory acceptance testing (FAT) and site commissioning of gear hobbing machines.
- Applied by: machine tool manufacturers, quality and metrology engineers, production managers, maintenance teams, and purchasers specifying acceptance criteria.
- Typical uses: procurement specifications, acceptance/inspection procedures, periodic accuracy verification, and troubleshooting runout, parallelism, coaxiality and transmission errors that affect gear quality.
Related standards
- ISO 230‑1 - Acceptance code for machine tools (geometric accuracy, instrument use, warm-up and installation)
- ISO 701 - International gear notation (symbols)
- ISO 1328 - Parallel involute gears (accuracy system)
Keywords: ISO 6545, gear hobbing machine testing, acceptance conditions, geometrical tests, kinematic tests, ISO 230‑1, transmission accuracy, work‑table, work‑steady.
