Overview
ISO 2759:2014 - Board - Determination of bursting strength defines a standardized hydraulic test method for measuring the bursting strength of board materials. The method applies to all types of board (including corrugated and solid fibreboard) with bursting strengths from 350 kPa to 5 500 kPa, and to component papers or boards down to 250 kPa when they are used in higher-strength assemblies. The standard covers apparatus, calibration, sampling/conditioning, test procedure, result expression and test reporting.
Key topics and technical requirements
- Scope and limits: Applicable range 350–5 500 kPa (250 kPa for component materials); alternative method ISO 2758 applies for many lower-strength materials.
- Principle: A test piece is clamped over a circular elastic diaphragm and subjected to increasing hydraulic pressure until rupture; bursting strength is the maximum pressure recorded.
- Apparatus essentials:
- Clamping system - annular, plane, parallel plates with grooved surfaces; clamping pressure repeatability required; concentricity within 0.25 mm.
- Diaphragm - natural or synthetic rubber, specific recessed mounting and bulge-height/pressure characteristics (e.g., 10 mm bulge at ~170–220 kPa; 18 mm bulge at ~250–350 kPa).
- Hydraulic system - motor-driven piston using compatible fluid (e.g., glycerol, glycol or low-viscosity silicone oil); pumping rate 170 ml/min ± 15 ml/min; system free of air.
- Pressure-measuring system - accuracy ±10 kPa or ±3%, response such that peak reading is within ±3% of true peak (see Annex D).
- Calibration and checks: Regular calibration of pressure and clamping systems; instrument warm-up and in-situ calibration recommended.
- Sampling & conditioning: Samples should be representative; condition in standard atmosphere per ISO 187; sampling guidance per ISO 186.
- Procedure & test counts: Use appropriate clamping pressures (guideline: up to 1 500 kPa → 400 kPa clamp; 1 500–2 000 → 600 kPa; 2 000–2 500 → 800 kPa; >2 500 → 1 000 kPa). Perform 20 valid tests (or 10 per side if separate surface results required).
- Results: Report mean bursting strength (kPa), standard deviation and optionally the burst index = p / g (kPa·m²/g), where p = mean burst pressure and g = grammage per ISO 536.
Applications and users
ISO 2759:2014 is used by:
- Packaging manufacturers (corrugated and solid board)
- Paper and board test laboratories and QC departments
- Raw material suppliers and converters assessing component strength
- Product designers and certification bodies verifying material performance
Practical applications include quality control, material specification, batch acceptance, and comparative testing of board/packaging materials.
Related standards
- ISO 2758 - alternative bursting test for many lower-strength materials
- ISO 536 - determination of grammage (used for burst index)
- ISO 187 - standard atmosphere for conditioning/testing
- ISO 186 - sampling to determine average quality
Keywords: ISO 2759:2014, bursting strength, burst index, board testing, corrugated board, hydraulic burst test, diaphragm, clamping pressure, ISO 2758, ISO 536.
