ISO 3077:2001

Overview

ISO 3077:2001 specifies requirements for short-link, fine-tolerance hoist chain of Grade T - types T, DAT and DT - intended for use in manually operated or power-driven chain hoists. The standard applies to electrically welded, round steel short-link chain, heat-treated and tested per ISO 1834, in the nominal chain size range 3 mm to 22 mm. It covers dimensional tolerances, material and heat-treatment requirements, mechanical properties, verification tests, marking and documentation.

Key topics and technical requirements

• Scope & chain types
  • Types DAT and DT: surface-hardened (case depth) for power-driven hoists only.
  • Type T: may be used in lifting equipment other than hoists.
• Dimensions & tolerances
  • Nominal sizes 3–22 mm, pitch based on 3·d (up to 3.2·d), weld diameter limited to max +8% over nominal.
  • Detailed dimensioning and tolerance calculations are given in Annex A.
• Material & metallurgy
  • Steel made by electric or oxygen-blown processes, fully killed, grain size ≤ 5 (ISO 643).
  • Minimum alloying elements (e.g., Ni, Cr, Mo as appropriate per chain type) and limits for S + P to control brittleness.
• Heat treatment
  • Chains shall be hardened, case-hardened, or both, and tempered from above the AC3 point before proof testing.
• Mechanical properties & loading
  • Working Load Limits (WLL) specified for each nominal size and type (e.g., DAT 3 mm = 0.28 t up to DAT 22 mm = 15 t).
  • Manufacturing Proof Force (MPF), breaking force, elongation and mean stress criteria are defined; calculation methods in Annex A.
• Verification & testing
  • Sampling, MPF tests, breaking force, total ultimate elongation, bend deflection, Vickers hardness testing (ISO 6507-1) and fatigue resistance tests for types DAT/DT.
• Identification & documentation
  • Requirements for grade marking, identification, inspection marks and manufacturer’s certificate; guidance on assembly, inspection and in-service use.

Applications - who uses ISO 3077:2001

• Chain manufacturers - to design, heat-treat and certify fine-tolerance hoist chain.
• Hoist and lifting-equipment designers - for component selection and WLL verification.
• Procurement and QA teams - to specify compliant chain for manual and power-driven hoists.
• Test laboratories and inspectors - for mechanical and fatigue testing, hardness checks and acceptance sampling.
• Maintenance and safety officers - to apply inspection intervals and replacement criteria stated in the standard.

Related standards

• ISO 1834 - Short link chain for lifting purposes: general conditions of acceptance
• ISO 643 - Steel: micrographic grain size
• ISO 6507-1 - Vickers hardness test
• ISO 4301-1, ISO 4965, EN 10002-2 - referenced for testing and classification

ISO 3077:2001 is essential when specifying fine-tolerance short-link hoist chain, ensuring dimensional control, material quality, heat treatment and verified mechanical performance for safe lifting operations.