EN ISO 898-5:2012 PDF

Overview

EN ISO 898-5:2012 (ISO 898-5:2012) specifies the mechanical and physical properties of set screws and similar threaded fasteners made of carbon steel or alloy steel. It covers fasteners with ISO metric triangular threads (coarse and fine pitch) tested at an ambient temperature of 10 °C to 35 °C. Fasteners conforming to this part are classified by specified hardness classes and are intended for use under compressive stress only. The standard applies to common metric sizes (coarse thread M1.6 to M30; fine pitch M8×1 to M30×2) and references established thread dimensions and tolerances.

Key topics and requirements

• Hardness classes and designation: hardening classes are designated as 14H, 22H, 33H and 45H. The numerical part equals one-tenth of the minimum Vickers hardness (HV min: 140, 220, 330, 450 respectively).
• Material and heat treatment limits: requirements for carbon/alloy steels and basic chemical composition limits for each class.
• Thread form and sizes: ISO metric triangular thread per ISO 68-1; diameter/pitch per ISO 261/262; thread tolerances per ISO 965-1/2.
• Test methods: specified procedures include hardness testing, decarburization and carburization assessment, and a proof torque test (for certain hexagonal/hexalobular socket set screws of hardness class 45H).
• Inspection levels: manufacturer, supplier and purchaser inspection applicability and responsibilities.
• Marking and traceability: rules for manufacturer identification, hardness-class marking and package labelling.
• Hydrogen embrittlement: informative Annex A covers hydrogen embrittlement relief after electroplating.
• Limitations: the standard does not specify tensile/shear strength, weldability, corrosion resistance or suitability outside the -50 °C to +150 °C application guidance (users must consult metallurgists for extreme temperatures up to +300 °C).

Applications

• Standardizes set screws and similar threaded fasteners used to locate or secure components where compressive loading is primary (e.g., mechanical assemblies, locking components, machine tool fixtures).
• Ensures consistent hardness, surface integrity and testing so fasteners perform predictably in assembly, maintenance and production environments.
• Supports procurement specifications, quality control, and conformity assessment for manufacturers and suppliers of metric set screws.

Who uses this standard

• Fastener manufacturers and heat-treatment shops
• Design and mechanical engineers specifying fasteners
• Quality assurance, inspection labs and procurement teams
• Metallurgists advising on material and temperature suitability

Related standards

• ISO 68-1 (metric thread form), ISO 261 / ISO 262 (diameter/pitch), ISO 965-1 / ISO 965-2 (thread tolerances)
• ISO 225 (symbols), ISO 6506 / 6507 / 6508 (hardness tests), ISO 6157-1 (surface discontinuities), ISO 16426 (quality assurance)
• Other parts of ISO 898 (Parts 1, 2, 6, 7) for complementary fastener properties

Keywords: EN ISO 898-5:2012, ISO 898-5, set screws, fasteners, hardness classes, metric thread, mechanical properties, hardness testing.