ISO 26623-2:2014

Overview

ISO 26623-2:2014 defines the dimensions and designation of polygon-receivers for polygonal taper interfaces with a flange contact surface. This standard applies to polygon-receivers used for automatic and manual tool exchange on machine tools (turning, drilling, milling, turn/mill centres and grinding machines). Torque is transmitted by form lock (polygon) and the flange contact surface is decisive for interface stiffness and seating.

Key Topics and Requirements

• Dimensions and sizes: Specifies polygon-receiver geometry and dimensional data (figures and Table 1) for a range of nominal sizes up to 100 mm. The detailed receiver dimensions are given together with surface and profile notes.
• Tolerances: Linear and angular tolerances without individual indications are to be applied as tolerance class “m” (ISO 2768-1); geometrical tolerances as class “K” (ISO 2768-2).
• Clamping forces: Defines recommended clamping forces (Annex A) to ensure proper flange contact and elastic seating of the taper. Typical guidance:
  • Nominal size 32 → 15 kN
  • 40 → 20 kN
  • 50 → 25 kN
  • 63 → 30 kN
  • 80 / 80X → 40 kN
  • 100 → 60 kN These values ensure at least 80% of the clamping action acts on the flange surface under tolerance variations.
• Designation: Standardized naming convention for receivers: e.g. POLYGON-RECEIVER ISO 26623-2 - PSC 32.
• Clamping system responsibility: The clamping system should be specified by the receiver or spindle manufacturer; permissible speeds, torque capacities and bending loads should be supplied by the manufacturer.

Applications and Users

ISO 26623-2 is directly relevant for:

• Machine tool builders and spindle designers specifying polygonal taper interfaces.
• Tool and holder manufacturers producing compatible polygon-receivers for automatic/manual tool change.
• Maintenance engineers, quality and procurement teams verifying dimensional conformity and ensuring correct clamping force selection.
• Fixture designers and integrators who need consistent torque transmission by form lock and reliable flange seating for stiffness.

Practical benefits include standardized interoperability between shanks and receivers, predictable torque capacity, and clearer specification for clamping systems and maintenance.

Related Standards

• ISO 26623-1 - Part 1: Dimensions and designation of shanks (complements Part 2)
• ISO 2768-1 / ISO 2768-2 - General tolerances (linear/angular and geometrical)
• ISO 1101 - Geometrical tolerancing (referenced for form/orientation/run-out)

Keywords: ISO 26623-2, polygonal taper interface, polygon-receiver, flange contact surface, dimensions, clamping forces, machine tools, tool exchange, form lock, spindle designation.