ISO 5609-3:2012

Overview

ISO 5609-3:2012 specifies requirements for tool holders for internal turning with cylindrical shank - Part 3: Style K. Style K tool holders have a reduced (step) shank and a cutting edge angle κ = 75°, and are intended for use with indexable inserts (hardmetal, ceramic or other cutting materials) mounted by clamping for internal turning operations. The standard defines key dimensions, designation rules, materials, design options and delivery/marking requirements.

Key topics and technical requirements

• Scope and purpose: Standardizes physical and identification characteristics of style K internal turning holders to ensure interchangeability and reliable performance in internal boring/tuning operations.
• Dimensions: Preferred symbols and dimensional data (see Table 1 in the standard) cover shank diameters, lengths, cutting-edge lengths, insert thickness (s), and mounting features. The standard aligns symbols with ISO 13399 for cutting tool data representation.
• Designation: Prescribes the designation format combining the part reference (ISO 5609-3), mounting/type symbols, diameter/length codes and insert/handing codes. Example format is provided in the document.
• Materials: Permitted materials include high-strength steel (≥1 000 N/mm2 tensile), brazed hardmetal heads, or heavy metal tools - material selection is left to the manufacturer.
• Design options: Allows variants with or without lubrication holes and antivibration devices; mounting types follow Table 1 unless otherwise agreed.
• Corner radius and insert thickness: Specifies nominal corner radii applicable to listed cutting-edge lengths and gives rules to determine f and l dimensions for non-standard radii or insert thicknesses (see ISO 5609-1 for calculations).
• Extent of delivery and marking: Tool holders are delivered with clamping device but without inserts. Marking must include the manufacturer and letter symbol; packaging should reference ISO 5609-3.

Practical applications and users

Who benefits:

• Tooling manufacturers and designers creating internal turning holders to conform to international norms.
• Machine shops and CNC programmers specifying tooling for internal turning/boring jobs.
• Procurement and quality engineers ensuring compatibility and traceability across suppliers.
• CAD/CAM libraries and parts-data managers using standardized symbols and dimensions for tooling data exchange.

Typical applications:

• Internal turning/boring operations on lathes and boring bars where indexable inserts are used for efficient tool changes.
• Situations requiring standardized interchangeability for tooling spares and multi-supplier sourcing.

Related standards

• ISO 5609-1 (Designation, styles, dimensions and calculation for corrections)
• ISO 5609-2, -4, -5, -6 (other styles: F, L, U, Q)
• ISO 1832 (Indexable inserts designation)
• ISO 13399 (Cutting tool data representation and exchange)

Keywords: ISO 5609-3:2012, tool holders for internal turning, cylindrical shank, style K, indexable inserts, cutting edge angle 75°, designation, dimensions, corner radius, insert thickness, clamping.