Overview
ISO 12090-1:2011 - Rolling bearings - Profiled rail guides for linear motion rolling bearings - Part 1: Boundary dimensions and tolerances for series 1, 2 and 3 - specifies the boundary dimensions and tolerances for profiled rail guides (monorail guidance systems) used in linear motion rolling bearings. The standard covers typical sizes (series 1, 2 and 3, including carriage and rail sizes from about 15 up to 125), defines datum faces, symbols and terms, and provides the tables, figures and tolerance rules needed for mechanical design, manufacture and inspection. It also states that the internal design of the profiled rail guides is at the manufacturer’s discretion and that interchangeability between assemblies is limited to the manufacturer’s permitted combinations.
Key Topics and Requirements
- Boundary dimensions: nominal carriage widths, carriage lengths, profiled rail widths and heights, and other envelope dimensions defined in tables and figures for series 1–3.
- Tolerances: dimensional tolerances and running-parallelism limits (vertical and horizontal) for reliable interchange and predictable performance.
- Design types: standard and long carriages (e.g., 1M, 1L, 2M, 2L, 3M, 3L) and profiled rail fixing methods (from above “T” or from below “B”).
- Mounting provisions: mounting hole patterns, thread/through-hole options, bolt-hole centres and recommended bolt diameters for different sizes.
- Measurement and symbols: definitions of reference faces, nominal distances (A, H, W, B, J, etc.), variation metrics (∆A, V_A, ∆H, V_H) and other symbols per ISO 15241.
- Interchangeability note: assemblies (one or more carriages on a rail) must follow manufacturer-specified combinations; full interchangeability is not guaranteed beyond those limits.
Applications and Who Uses This Standard
ISO 12090-1:2011 is intended for:
- Machine designers and mechanical engineers specifying linear guides for automation, CNC machines, robotics, semiconductor equipment, medical devices and material handling systems.
- Manufacturers and suppliers of linear motion systems for consistent product envelopes and mounting compatibility.
- Quality, test and inspection teams ensuring parts meet boundary dimensions and tolerance requirements.
- Purchasing and integration engineers verifying mechanical interchangeability across suppliers (within manufacturer limits).
Practical benefits include simplified CAD integration, reduced design rework, clearer procurement specifications and improved assembly alignment and performance.
Related Standards
Keywords: ISO 12090-1:2011, rolling bearings, profiled rail guides, linear motion rolling bearings, boundary dimensions, tolerances, carriages, profiled rails, running parallelism, interchangeability.
Open preview (PDF)Rolling bearings — Profiled rail guides for linear motion rolling bearings — Part 1: Boundary dimensions and tolerances for series 1, 2 and 3