Overview
ISO 3655:1986 specifies acceptance conditions and accuracy tests for vertical turning and boring lathes with one or two columns and a single fixed or movable table. The standard defines the machining operations that can be performed, describes machine types and nomenclature (English, French and Russian; equivalents in German, Italian and Swedish), and sets out geometrical and practical tests together with the corresponding permissible deviations for general-purpose, normal-accuracy machines. ISO 3655 deals only with verification of machine accuracy - it does not cover machine running behavior (vibration, noise, stick‑slip) or machine performance characteristics (speeds, feeds).
Key topics and technical requirements
- Machine classification and nomenclature: single-column and two-column configurations; fixed vs movable table; components such as table, base, column, rail, railhead, ram and side head.
- Defined machining operations: turning, facing, threading, scroll cutting and other typical vertical-lathe processes.
- Geometrical tests and practical tests referenced to ISO 230/1 (installation, warm-up, measuring methods). Tests include:
- Table flatness and camming (run‑out)
- Table bore and external table cylindrical run‑out
- Squareness of vertical slideways to the table surface
- Parallelism of railhead and tool slide movements to the table axis
- Turret housing axis alignment relative to slide movement
- Measuring instruments and methods: use of dial gauges, straightedges, precision levels, gauge blocks and test mandrels as referenced in ISO 230/1.
- Tolerancing guidance: permissible deviations are provided for the listed tests; the standard also notes practical constraints (e.g., minimum measurable tolerance of 0.005 mm / 0.0002 in for geometrical and practical tests).
Practical applications and users
Who uses ISO 3655:
- Machine tool manufacturers and designers - to specify acceptance tests and nominal accuracy for vertical lathes.
- Purchasing agents and end users - to define acceptance criteria when ordering or receiving machines.
- Test laboratories and QA/inspection teams - to perform standardized geometric and practical accuracy checks during acceptance and after major maintenance.
- Service and maintenance engineers - to verify alignment and reprovision machines to standard tolerances.
Practical value:
- Ensures consistent acceptance criteria across suppliers and buyers.
- Helps confirm that a vertical lathe meets the positional and geometric accuracy required for intended machining tasks (facing, boring, threading, scroll cutting).
- Facilitates objective pass/fail decisions based on standardized measurement methods.
Related standards
- ISO 230/1 - Machine tools - Acceptance code: geometrical accuracy (referenced extensively for methods and measuring accuracy)
- ISO 841 - Numerical control axis and motion nomenclature
- ISO 1101 - Geometrical tolerancing (form, orientation, location, run-out)
Keywords: ISO 3655, vertical turning and boring lathes, acceptance conditions, testing accuracy, geometrical tests, permissible deviations, ISO 230/1, table run-out, railhead, dial gauge.