ISO 3186:2008

Aerospace - Bolts, large bihexagonal head, normal shank, short or medium length MJ threads, metallic material, coated or uncoated, strength classes 1 250 MPa to 1 800 MPa - Dimensions

ISO 3186:2008 specifies the dimensions of large bihexagonal head bolts, with close or large tolerance normal shank and short or medium length MJ threads, in metallic material, coated or uncoated, with strength classes 1 250 MPa to 1 800 MPa. ISO 3186:2008 is applicable to the compilation of aerospace product standards.

Aéronautique et espace — Vis à tête bihexagonale large, avec tige normale et filetages MJ courts ou de longueur moyenne, en matériau métallique, revêtues ou non revêtues, des classes de résistance 1 250 MPa à 1 800 MPa — Dimensions

General Information

• Status: Published
• Publication Date: 17-Aug-2008
• ICS: 49.030.20 - Bolts, screws, studs
• Technical Committee: ISO/TC 20/SC 4 - Aerospace fastener systems
• Drafting Committee: ISO/TC 20/SC 4 - Aerospace fastener systems
• Current Stage: 9093 - International Standard confirmed
• Start Date: 24-Sep-2023
• Completion Date: 13-Dec-2025

Relations

• Consolidated By: ISO 2420:2017 - Leather - Physical and mechanical tests - Determination of apparent density and mass per unit area
• Effective Date: 06-Jun-2022
• Revises: ISO 3186:1994 - Aerospace - Bolts, large bihexagonal head, normal shank, short or medium length MJ threads, metallic material, coated or uncoated, strength classes 1 250 MPa to 1 800 MPa - Dimensions
• Effective Date: 15-Apr-2008

Overview

ISO 3186:2008 specifies the dimensions and related dimensional requirements for large bihexagonal‑head bolts used in aerospace applications. It covers bolts with normal shank (close or large tolerance), short or medium length MJ threads, made of metallic material (coated or uncoated), and strength classes 1 250 MPa to 1 800 MPa. The standard is intended for inclusion in aerospace product standards and replaces the 1994 edition.

Key topics and technical requirements

• Bolt configuration and dimensions: Detailed geometry is defined by Figure 1 and Table 1 in the standard (major/minor diameters, head geometry, thread length L, grip/shank details).
• Thread form and series: MJ thread forms and limits are referenced and coordinated with ISO 5855-2 and ISO 3353-1 for rolled external threads.
• Tolerances and fits: Dimensional tolerances and tolerances after coating are specified in millimetres; hole and shaft tolerance grades (e.g., H13, h6) conform to ISO 286-2. Tolerances of form and position refer to ISO 7913 unless otherwise stated.
• Coatings and measurement: Dimensions apply after any coating is applied (with specific pre‑coating shank tolerances noted for heat‑cured organic matrix coatings). Measurements are taken before lubricant application.
• Wrenching and drive details: Wrenching configuration and drive dimensions align with ISO 4095 for bihexagonal drives.
• Strength classes: Bolts in the scope are explicitly limited to 1250 MPa – 1800 MPa, covering high‑strength aerospace fasteners.

Applications and users

• Aerospace design engineers specifying fasteners for airframes, engine mounts, landing gear, and structural assemblies.
• Fastener manufacturers and suppliers producing MJ‑threaded, bihexagonal‑head bolts to aerospace dimensional requirements.
• Quality assurance and inspection teams performing dimensional checks, acceptance sampling, and conformity verification.
• Procurement and maintenance organizations ensuring parts ordered or replaced meet aerospace product standard dimensions and tolerances.
• Standards writers and certification bodies incorporating bolt dimension requirements into aircraft product standards and technical specifications.

Related standards

• ISO 5855-2 - MJ threads limit dimensions for bolts and nuts
• ISO 3353-1 - Rolled external threads (lead and runout)
• ISO 4095 - Bihexagonal drives - wrenching configuration
• ISO 286-2 - Limits and fits (tolerance grades)
• ISO 7913 - Tolerances of form and position for aerospace bolts and screws

Keywords: ISO 3186:2008, aerospace bolts, bihexagonal head bolts, MJ threads, bolt dimensions, aerospace fasteners, 1250 MPa, 1800 MPa, ISO standards.

Standards Content (Sample)

INTERNATIONAL ISO
STANDARD 3186
Second edition
2008-08-15
Aerospace — Bolts, large bihexagonal
head, normal shank, short or medium
length MJ threads, metallic material,
coated or uncoated, strength classes
1 250 MPa to 1 800 MPa — Dimensions
Aéronautique et espace — Vis à tête bihexagonale large, avec tige
normale et filetages MJ courts ou de longueur moyenne, en matériau
métallique, revêtues ou non revêtues, des classes de résistance
1 250 MPa à 1 800 MPa — Dimensions

Reference number
©
ISO 2008
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Foreword
ISO (the International Organization for Standardization) is a worldwide federation of national standards bodies
(ISO member bodies). The work of preparing International Standards is normally carried out through ISO
technical committees. Each member body interested in a subject for which a technical committee has been
established has the right to be represented on that committee. International organizations, governmental and
non-governmental, in liaison with ISO, also take part in the work. ISO collaborates closely with the
International Electrotechnical Commission (IEC) on all matters of electrotechnical standardization.
International Standards are drafted in accordance with the rules given in the ISO/IEC Directives, Part 2.
The main task of technical committees is to prepare International Standards. Draft International Standards
adopted by the technical committees are circulated to the member bodies for voting. Publication as an
International Standard requires approval by at least 75 % of the member bodies casting a vote.
Attention is drawn to the possibility that some of the elements of this document may be the subject of patent
rights. ISO shall not be held responsible for identifying any or all such patent rights.
ISO 3186 was prepared by Technical Committee ISO/TC 20, Aircraft and space vehicles, Subcommittee SC 4,
Aerospace fastener systems.
This second edition cancels and replaces the first edition (ISO 3186:1994), which has been technically revised.

INTERNATIONAL STANDARD ISO 3186:2008(E)

Aerospace — Bolts, large bihexagonal head, normal shank,
short or medium length MJ threads, metallic material, coated or
uncoated, strength classes 1 250 MPa to 1 800 MPa —
Dimensions
1 Scope
This International Standard specifies the dimensions of large bihexagonal head bolts, with close or large
tolerance normal shank and short or medium length MJ threads, in metallic material, coated or uncoated, with
strength classes 1 250 MPa to 1 800 MPa.
This International Standard is applicable to the compilation of aerospace product standards.
2 Normative references
The follow
...