Overview
ISO 6779:2023 - Test conditions for vertical internal type broaching machines - Testing of accuracy defines the procedures and acceptance guidelines for verifying the geometric accuracy of vertical internal broaching machines whose main cutting axis (Z‑axis) is vertical. With reference to ISO 230‑1, this standard explains machine concepts, axis designation and terminology, lists geometric tests (Clause 6) and machining tests (Clause 7), and gives tolerances for normal‑accuracy machines. NOTE: ISO 6779:2023 covers accuracy verification only - it does not address operational testing (vibration, abnormal noise, speeds/feeds).
Key technical topics and requirements
- Scope & reference: Measurement and test methods are given with explicit reference to ISO 230‑1:2012 for installation, levelling, warm‑up and measurement uncertainty.
- Terminology and axis designation: Defines components and axis names for vertical internal broaching machines (pull‑type/table‑up configurations).
- Measurement units: Linear dimensions in millimetres; angular deviations primarily expressed as ratios (conversion formulas provided).
- Permitted measuring instruments: Examples include precision levels, dial test indicators (DTIs), LVDTs, straightedges, squares, test mandrels; equivalent instruments with equal or better uncertainty may be used.
- Representative geometric tests and tolerances (examples from Clause 6):
- Flatness of work table (G1): 0.040 mm for measuring length up to 1 000 mm.
- Squareness of pulling chuck (Z‑axis) to work table (G2): 0.050 / 300 (0.165 / 1 000) (or the angular equivalent as given).
- Squareness of retrieving chuck (W‑axis) to work table (G3): 0.030 / 300 (0.100 / 1 000).
- Radial offset / coaxiality of pulling chuck hole relative to table centre (G4): 0.050 mm.
- Testing notes: Tests may be performed in any practical order to ease instrumentation setup. Tolerances in the standard are guideline values and can be adapted by mutual agreement between purchaser and supplier.
Practical applications
- Ensures geometric accuracy and traceable acceptance criteria during:
- Factory acceptance testing (FAT) and on‑site acceptance of broaching machines.
- Quality control and periodic verification programs in production shops.
- Supplier / purchaser contracts specifying agreed tolerances for delivered machines.
- Useful for establishing calibration procedures and documenting machine capability before production of high‑precision internal features (e.g., keyways, splines, internal profiles).
Who should use this standard
- Machine tool manufacturers and OEMs
- Metrology and test laboratories
- Plant quality, maintenance and production engineers
- Purchasing/specification teams procuring vertical internal broaching machines
Related standards
- ISO 230‑1:2012 - Test code for machine tools - Part 1: Geometric accuracy of machines operating under no‑load or quasi‑static conditions (normative reference used by ISO 6779:2023).
For implementation or purchasing, refer to the full ISO 6779:2023 document and coordinate test selection and tolerances with the machine supplier or national standards body.