ISO 8051:2016

Overview

ISO 8051:2016 specifies dimensional requirements for long shank machine taps with full‑diameter shanks and recesses, covering nominal thread diameters M3 to M10. This third edition (2016) is a minor revision that adds an informative annex linking the standard’s designations to the ISO 13399 cutting‑tool data model. ISO 8051 complements ISO 2283 (which covers relieved/reduced shank taps) and refers to ISO 8830 for technical specifications and marking.

Key topics and requirements

• Scope: Dimensions for full‑diameter shank taps with recess, nominal diameters M3–M10; intended for long shank machine taps.
• Dimensions and lengths: Threaded lengths follow ISO 529. Shank lengths (L – l) are increased by 50% compared with ISO 529, so overall lengths vary accordingly. Dimension details are given in the standard’s Figure 1 and Table 1.
• Recess: The recess is optional at the manufacturer’s discretion; when omitted the thread length is adjusted per the note in the standard.
• Tolerances: Shank and square tolerances refer to ISO 237 - precision shanks use h9, non‑precision h11, and form/position errors of the square can increase tolerance to h12.
• Marking: Marking requirements are specified by reference to ISO 8830.
• Data mapping: Annex A provides a relationship between ISO 8051 designations and preferred symbols in ISO 13399 for tool data representation and exchange.

Applications and who uses it

• Tool manufacturers: to design and produce long shank full‑diameter taps that meet standardized dimensions and tolerances.
• Machining and production engineers: for selection and specification of taps in CNC and machine‑tool operations requiring long‑reach tapping.
• Procurement and quality control: to verify dimensional conformity, marking, and interchangeability of taps from different suppliers.
• CAD/CAM and tooling data managers: use the Annex A mapping to ISO 13399 to integrate tap data into digital tool libraries and tool‑management systems.
• Standards and compliance teams: ensure shop practices and documentation reference the correct series (ISO 8051 for full‑diameter shank taps; ISO 2283 for reduced shanks).

Related standards

• ISO 2283 - Long shank taps (reduced shank)
• ISO 8830 - High‑speed steel machine taps: technical specifications and marking
• ISO 529 - Short machine taps and hand taps (threaded lengths reference)
• ISO 237 - Rotating tool shank diameters and drive square sizes (tolerances)
• ISO 13399 - Cutting tool data representation and exchange (Annex A mapping)

Keywords: ISO 8051, long shank taps, full‑diameter shank taps with recess, M3 to M10 taps, tap dimensions, machine taps standard, ISO 8830, ISO 2283, ISO 13399.