ISO 1120:2012

Overview

ISO 1120:2012 - Conveyor belts - Determination of strength of mechanical fastenings - Static test method - specifies a standard static test to measure the breaking strength of mechanical fastenings used on conveyor belts. The procedure applies to mechanical joints that either employ a connecting rod or do not employ a connecting rod. This standard does not cover vulcanized joints and is not applicable to light conveyor belts (see ISO 21183-1).

Key topics and requirements

• Test principle: apply an increasing tensile force to a prepared test piece until the mechanical fastening fails; record the maximum force.
• Apparatus: metallic adapter plate (for joints with connecting rods) and a dynamometer in accordance with ISO 283.
• Test piece preparation:
  • Full-thickness belt specimens cut longitudinally, minimum 150 mm width and at least 100 mm + gripped length.
  • Fastening (overall width) must be ≥ 100 mm; number of hooks determined by 100 ÷ pitch, rounded up.
  • Three test pieces are required per test.
• Conditioning and test conditions:
  • Tests start ≥ 24 h after manufacture (includes 8 h conditioning at specified temperatures).
  • Conditioning/testing temperatures: (23 ± 2) °C or (20 ± 2) °C (temperate) or (27 ± 2) °C (tropical).
  • In case of dispute, conditioning period is 72 h.
• Procedure:
  • Grips separated at rate (100 ± 10) mm/min; ensure symmetric loading to avoid edge-initiated rupture.
  • Record maximum breaking force.
• Results and reporting:
  • Report average breaking strength as newtons per millimetre (N/mm) of fastening width and as a percentage of full-thickness nominal tensile strength (reference ISO 283-1).
  • Test report must include fastening width, fastener and belt brand/type, results, failure mode, and conditioning/test temperature.

Applications and users

ISO 1120:2012 is used by:

• Conveyor belt manufacturers and fastener suppliers for quality control and product development.
• Testing laboratories and inspection bodies performing mechanical fastening strength verification.
• Mining, bulk material handling, and heavy-industry operations that rely on robust mechanical splices. Practical benefits include eliminating mechanically inadequate fastenings and establishing consistent, repeatable static-strength data for procurement and safety decisions.

Related standards

• ISO 283 - referenced for dynamometer and tensile properties (full-thickness tensile strength).
• ISO 21183-1 - covers light conveyor belts (ISO 1120:2012 is not applicable to these).

Keywords: ISO 1120:2012, conveyor belts, mechanical fastenings, static test method, breaking strength, dynamometer, connecting rod, N/mm, conveyor belt testing.