Overview
ISO 7719:2012 specifies the characteristics of prevailing torque type all‑metal hexagon regular nuts (metric) with threads from M5 to M36, and with property classes 5, 8 and 10. It covers dimensional limits, product grades, material and general requirements, and references related ISO standards for thread, mechanical, coating and inspection requirements. Dimensions correspond with ISO 4032 (except for the height h), and the prevailing‑torque feature form is at the manufacturer's discretion.
Key topics and requirements
- Scope of parts: All‑metal hexagon regular nuts with prevailing torque - threads M5 up to and including M36.
- Property classes: 5, 8 and 10 (mechanical/performance classification).
- Product grades: Grade A for D ≤ M16; Grade B for D > M16.
- Material: Steel (general requirements referenced).
- Thread tolerance: Class 6H.
- Dimensional data: Provided in the standard (Figure 1 and Table 1); many dimensions match ISO 4032 except h. Geometric guidance for the prevailing‑torque element is included (e.g., β = 15°–30°, θ = 90°–120°).
- Surface and finishing: Electroplating per ISO 4042; non‑electrolytic zinc‑flake coatings per ISO 10683; other finishes by agreement. Surface discontinuities limits per ISO 6157‑2.
- Mechanical and performance references: ISO 898‑2 and ISO 2320 for mechanical properties and prevailing torque performance.
- Tolerances and acceptance: Product grade tolerances per ISO 4759‑1; acceptance inspection per ISO 3269.
- Designation example: Prevailing torque type hexagon regular nut ISO 7719 - M12 - 8
Applications and who uses it
- Manufacturers of metric fasteners use ISO 7719 to design and produce prevailing‑torque all‑metal hex nuts that meet consistent dimensional and mechanical requirements.
- Design engineers and specifiers in machinery, automotive, heavy equipment, and general industrial sectors reference ISO 7719 when selecting self‑locking hex nuts for vibration‑prone assemblies.
- Purchasing and quality teams rely on the standard to define procurement specifications, inspection criteria and acceptance testing for prevailing‑torque nuts.
- Standards and compliance professionals use ISO 7719 together with related ISO fastener standards to ensure interoperability and traceability.
Related standards
ISO 7719 cross‑references key fastener standards, including: ISO 225, ISO 261, ISO 724, ISO 898‑2, ISO 965‑2, ISO 2320, ISO 3269, ISO 4042, ISO 4759‑1, ISO 6157‑2, ISO 8992 and ISO 10683. Use these together for complete specifications covering threads, mechanical properties, coatings and inspection.
Keywords: ISO 7719, prevailing torque nuts, all‑metal hexagon nuts, metric nuts M5‑M36, property class 5 8 10, product grade A B, fastener standards, self‑locking hex nuts.