Overview
ISO 10104:2018 specifies the outside dimensions for double-headed box wrenches used as assembly tools for screws and nuts. The standard covers both modified offset (Form A) and deep offset (Form B) double-headed box wrenches and defines overall lengths and the maximum head thicknesses for specified wrench pairings. It applies to the wrench types referenced in ISO 1703:2005 and is intended to ensure dimensional consistency for procurement, manufacturing and tool selection. The document does not set detailed technical specifications (those are in ISO 1711‑1:2016, series A).
Key Topics
- Scope and purpose: Defines overall length (l) and maximum head thickness (e) for double-headed box wrenches (Forms A and B). It focuses on outside dimensions to promote interchangeability and consistent clearances.
- Dimension rules: Table 1 in the standard lists lengths and maximum head thicknesses for nominal flat pairings (s × s) ranging from small pairings (e.g. 6 × 7) up to larger pairings (e.g. 55 × 60). For many nominal sizes, the overall length is determined by simple linear formulas - for example:
- l = s × 9 + 80 mm (for certain pairings)
- l = s × 9 + 60 mm (for larger pairings)
Figure 1 is included as an illustrative example only and does not constrain manufacturer design.
- Designation and marking: A compliant wrench must be designated with the reference to ISO 10104, the form (A or B) and the nominal pairing (s × s). Marking must include at least the nominal flat dimensions and the manufacturer or supplier name/mark.
- Related dimensional standards: The standard references ISO 691 (tolerances on openings) and ISO 3318 (maximum head envelope widths) for complementary dimensional requirements.
Applications
ISO 10104:2018 is practical for:
- Manufacturers designing and producing double-headed box wrenches to meet consistent length and head-thickness limits.
- Procurement teams specifying tooling for maintenance, service kits, and assembly operations to ensure interchangeability.
- Quality and inspection teams verifying compliance of wrench outside dimensions against a recognized international standard.
- Technical writers and cataloguers who must label and designate wrenches correctly (example designation: "Clé ISO 10104, B 13 × 15").
Benefits include improved fit in confined spaces, predictable clearance for offset forms, and standardized marking for traceability.
Related Standards
- ISO 1703:2005 - Nomenclature and designation for assembly tools (reference numbers referenced by ISO 10104).
- ISO 1711‑1:2016, series A - Technical specifications for hand wrenches and sockets (detailed product specs).
- ISO 691 - Tolerances for key openings and bit sockets.
- ISO 3318 - Maximum head envelope widths for spanner heads.
For manufacturer guidance and procurement, consult ISO 10104:2018 together with the referenced ISO documents to cover tolerances, head envelopes and product technical specifications.