ISO 9361-2:2011

Overview

ISO 9361-2:2011 specifies the dimensions and key geometric requirements for indexable ceramic inserts with rounded corners that have a cylindrical fixing hole and 0° normal clearance. These inserts are intended primarily for mounting by top-and-hole clamping or hole clamping alone on external and internal turning tools. The standard covers common insert shapes (triangular, square, rhombic, round) and links designation and measurement practices to other ISO series.

Key technical topics and requirements

• Scope and insert types: Standardizes TN (triangular), SN (square), CN (80° rhombic), DN (55° rhombic), VN (35° rhombic) and RN (round) ceramic inserts with rounded corners and no chip breakers.
• Fixing hole sizing: Fixing hole diameters are related to the insert inscribed circle; example nominal hole diameters given include 3.81, 5.16, 6.35 and 7.94 mm for typical inscribed-circle sizes (9.525, 12.7, 15.875, 19.05 mm). A tolerance of ±0.08 mm for the hole diameter is specified in the standard tables.
• Corner radii and m-dimension: Corner radius values (ε designations) are used to calculate the important m-dimension (mounting reference). Tables provide preferred r values and corresponding m dimensions for standard insert sizes.
• Cutting-edge condition and chamfers: Defines permitted cutting-edge conditions in accordance with ISO 1832, and allows additional chamfer/edge specifications (symbols such as T, S, K, P) to be appended to designations.
• Tolerances and interchangeability: Inserts are supplied in tolerance classes per ISO 1832 to ensure interchangeability. Recommended (first-preference) dimensions are given in the standard tables; non-preferred sizes are indicated for second preference.
• Measurement methods: Annex A gives measurement procedures (dial-gauge and precision roller methods) for m-dimension and inscribed-circle checks to ensure conformity.

Practical applications and users

• Who uses it: Tool manufacturers, insert producers, precision engineering shops, CNC turning tool designers, and procurement/specification engineers.
• Practical value:
  • Ensures interchangeability of ceramic indexable inserts across toolholders and suppliers.
  • Provides clear designation rules and measurement methods to support quality control and inventory management.
  • Helps designers select standardized insert geometries and fixing-hole sizes for robust mounting in turning operations.

Related standards

• ISO 9361-1 - ceramic inserts without fixing hole
• ISO 1832 - designation and tolerance classes for indexable inserts
• ISO 13399 series - data representation mapping (Annex C links ISO 9361-2 designations to ISO 13399 symbols)
• Relevant materials standards for ceramics (oxide, carboxide, nitride formulations) are described conceptually in the standard.

Keywords: ISO 9361-2:2011, indexable ceramic inserts, cylindrical fixing hole, cutting tools, turning inserts, insert dimensions, fixing hole diameter, cutting-edge condition, ISO 1832, ISO 13399.