Overview
EN ISO 1179-3:2008 / ISO 1179-3:2007 defines dimensions, performance requirements and test procedures for light-duty (L series) stud ends with ISO 228-1 threads that seal by O-ring with a retaining ring (types G - non‑adjustable, and H - adjustable). The standard applies to stud ends used in general-purpose and fluid‑power connections (hydraulic and pneumatic) and specifies materials and testing to ensure safe working and burst performance.
Key topics and requirements
- Scope and types: Covers non‑adjustable (type G) and adjustable (type H) light‑duty stud ends (L series) with O‑ring plus retaining ring sealing.
- Threads and dimensions: Uses ISO 228-1 pipe threads; detailed dimensional tables and figures for stud ends, locknuts and washers are provided.
- Materials: Typical construction is low carbon steel, plated; specific material and plating requirements are referenced.
- Working pressure: Design working pressures stated up to 31.5 MPa (315 bar) for non‑adjustable (G) and up to 20 MPa (200 bar) for adjustable (H); actual permissible pressure depends on size, material and application.
- Performance tests: Includes burst (failure) tests, impulse testing and other verification; burst-to-working pressure ratio requirement is 4:1 (three samples tested).
- Sealing components: O‑ring and retaining ring dimensions and quality are specified; O‑rings referenced to ISO 3601‑3 quality grades.
- Assembly and torques: Specifies assembly practices and torque values for testing (manufacturer must follow torque values listed in the standard).
- Design/identification: Rules for designation and identification statements for stud ends to ensure correct interoperability.
- Manufacturer responsibility: Conformance to dimensions alone does not guarantee rated performance - manufacturers must perform the specified tests to certify performance.
Applications and users
- Who uses it: Hydraulic and pneumatic component manufacturers, connector and fitting producers, system integrators, test labs, and procurement/specification engineers.
- Typical applications: Tube and hose connectors, shaped fittings (tees, elbows, crosses) where light‑duty stud ends with O‑ring sealing are required; general fluid‑power assemblies and retrofit or legacy systems that already use ISO 1179 series components.
- Design guidance: While ISO 1179‑3 remains maintained for existing systems, ISO committees recommend using newer preferred series (e.g., ISO 6149) for new hydraulic designs; ISO 1179‑3 is important for compatibility in existing installations.
Related standards
Keywords: EN ISO 1179-3:2008, ISO 1179-3, stud ends, ISO 228-1 threads, O‑ring seal, retaining ring, light‑duty L series, fluid power connectors, hydraulic fittings.
