ISO 5609-5:2012

Overview

ISO 5609-5:2012 specifies the characteristics of tool holders for internal turning with cylindrical shank - Style U. It covers tool holders with a reduced (stepped) cylindrical shank and a cutting edge angle κ = 93°, intended for use with indexable inserts (hardmetal, ceramic or other cutting materials) mounted by clamping for internal turning operations. The standard is part of the ISO 5609 series that defines designation, dimensions and design principles for internal turning tool holders.

Key topics and technical requirements

• Scope and purpose: Defines geometric characteristics, designation rules and basic design constraints for Style U internal turning holders.
• Dimensions and symbols: Provides preferred symbols aligned with ISO 13399 and tables of nominal dimensions (shank diameter d, overall length l, cutting-edge length l1, distance f, insert width D, insert thickness s) for rhombic insert shapes D and V.
• Cutting geometry: Style U holders have a cutting edge angle of 93° (κ) and are intended for inserts with included angles (ε) such as 35° or 55° depending on shape.
• Designation system: Specifies how to designate a tool holder (reference to ISO 5609-5 plus supplementary symbols for diameter, length, mounting type, insert shape, clearance angle, hand/right-left, cutting-edge length).
• Materials: Permits manufacture from high‑strength steel (≥1 000 N/mm² tensile), brazed carbide heads on steel, or heavy metal - material choice is left to the manufacturer.
• Design options: Allows variants with or without lubrication holes and with or without antivibration devices; mounting types follow tables but may be modified by agreement.
• Corner radii and inserts: Defines nominal corner radii and how f and l are related to insert corner radius r; alternative radii follow ISO 5609‑1 rules.
• Delivery and marking: Tool holders are supplied complete with clamping devices but without inserts; marking must include the manufacturer’s symbol and ISO 5609-5 reference on packaging.

Applications and users

ISO 5609-5:2012 is used by:

• CNC tool designers and tooling engineers specifying internal turning tool holders for bores and internal profiles
• Cutting tool manufacturers and suppliers producing or verifying Style U holders
• Production and maintenance engineers selecting holders for indexable inserts (carbide, ceramic)
• Purchasing and quality teams ensuring conformity to international tooling dimensions and designation Practical applications include precision boring, internal profiling, and turning operations in metalworking industries where standardized holder geometry ensures tool interchangeability and predictable cutting performance.

Related standards

• ISO 5609-1: Designation, styles, dimensions and calculation for corrections (normative reference)
• ISO 5609 (Parts 1–6): Other styles (F, K, L, Q)
• ISO 1832: Indexable inserts - Designation
• ISO 13399: Cutting tool data representation and exchange

Keywords: ISO 5609-5:2012, tool holders, internal turning, cylindrical shank, Style U, indexable inserts, cutting edge angle 93°, internal boring, tooling standard.