Overview
EN ISO 2759:2014 - "Board: Determination of bursting strength (ISO 2759:2014)" is a CEN-endorsed test standard that specifies a hydraulic method to measure the bursting strength of paper and board. The method uses an elastic diaphragm pressed against a clamped circular test piece while hydraulic pressure is increased until rupture. It applies to all board types (including corrugated and solid fibreboard) with bursting strengths from 350 kPa to 5 500 kPa, and to papers/boards down to 250 kPa when they are components of stronger combined materials.
Key topics and technical requirements
- Principle: Maximum hydraulic pressure required to force a rubber diaphragm through a clamped circular area until rupture (bursting pressure).
- Applicable range: 350–5 500 kPa (250 kPa minimum for component testing).
- Apparatus essentials:
- Clamping system with annular, parallel, grooved plates; clamping pressure repeatable and within 700–1 200 kPa.
- Elastic diaphragm (natural or synthetic rubber) with specified recess and bulge characteristics (e.g., 10 mm ±0.2 mm bulge: 170–220 kPa; 18 mm ±0.2 mm bulge: 250–350 kPa).
- Hydraulic system using compatible liquid (e.g., glycerol, ethylene glycol, silicone oil) with pumping rate 170 ml/min ±15 ml/min; system must be free of air.
- Pressure-measuring system with display accuracy of ±10 kPa or ±3% (whichever greater) and response such that peak pressure is within ±3% of true peak (see Annex D).
- Calibration & maintenance: Regular calibration of pumping rate, pressure-sensor and clamping indicators; diaphragms checked and replaced when bulge specs fail.
- Sampling & conditioning: Test pieces must be representative (ISO 186) and conditioned per ISO 187; grammage used for derived burst index (ISO 536).
- Precision & testing guidance: Precision data and clamp dimensions/testing procedures provided in normative annexes (Annexes A–E).
Applications
- Quality control and acceptance testing of paper, board and carton materials.
- Specification verification for packaging (flat or corrugated) and converted products.
- R&D and material comparison (bursting strength and burst index).
- Supplier qualification and production troubleshooting where mechanical strength under pressure is critical.
Who should use this standard
- Paper and board manufacturers
- Corrugated converters and pack design engineers
- Independent testing laboratories and QA departments
- Procurement/specification engineers requiring standardized performance data
Related standards
- ISO 2758 - alternative method for lower bursting strengths
- ISO 186 - sampling to determine average quality
- ISO 187 - standard atmosphere for conditioning and testing
- ISO 536 - determination of grammage
Using EN ISO 2759:2014 ensures consistent, reproducible bursting-strength data for product specification, regulatory compliance and quality assurance in paper and board industries.
