Overview
ISO 3936:1993 defines the dimensions and tolerances for reduction sleeves with tenon drive using the 7/24 taper system. Published as the third edition in 1993, the standard covers specific external and internal 7/24 taper sizes and references ISO 297 for the detailed 7/24 taper geometry. The document contains dimensional drawings (figure 1) and a tolerance table (table 1) with measurements in millimetres.
Key topics
- Scope and nominal sizes
- External 7/24 taper sleeves: Nos. 40, 45, 50 and 60
- Internal 7/24 taper sleeves: Nos. 30, 40, 45 and 50
- Dimensional definitions and drawing references
- Provides a figure for key dimensions and a measurement plane; some dimension labels (D, DA, l1, i, n) are defined by reference to ISO 297.
- Tolerances
- Includes a tolerance table (in millimetres) covering allowable deviations for the listed taper sizes to ensure proper fit and performance.
- Normative reference
- 7/24 taper geometry and related dimensions are governed by ISO 297:1988, cited as a normative reference.
- Quality control considerations
- The standard addresses tolerances relevant to concentricity and fit (including total radial runout considerations noted in the foreword), supporting consistent interchangeability of sleeves and toolholders.
Applications
ISO 3936:1993 is directly applicable where reduction sleeves with tenon drives are used to adapt tool shank sizes on milling machines and other machine tools. Typical uses include:
- Adapting larger spindles or toolholders to accept smaller tool shanks
- Manufacturing and inspection of reduction sleeves and tenon-drive adapters
- Ensuring interchangeability and safe mechanical fit between toolholders, milling cutters, and machine spindles
- Specifying procurement and acceptance criteria for tooling accessories in production and maintenance
Who uses this standard:
- Tool and holder manufacturers
- Machine-tool OEMs and maintenance shops
- Quality and metrology engineers verifying dimensional conformity
- Purchasing and standards compliance teams specifying tooling accessories
Related standards
- ISO 297:1988 - 7/24 tapers for tool shanks for manual changing (normative reference for taper geometry)
- Technical context: prepared by ISO/TC 29 (Small tools), Sub‑Committee SC 7 (Milling cutters and milling-machine accessories)
Keywords: ISO 3936, reduction sleeves, tenon drive, 7/24 taper, dimensions, tolerances, ISO 297, toolholders, milling machine accessories.