Definition
A breakage resistance meter is an instrument used to determine the ability of a material to resist breakage when subjected to uniform vertical pressure. This device is widely used to evaluate the mechanical strength of flakes or corrugated materials, and its measurements are typically expressed in bursting strength in kilopascals or pound-force per square inch.
How it works:
The instrument works on the principle of hydraulic incrementation. During testing, the specimen is fixed between two ring clamps with the lower clamp connected to an expandable rubber membrane. The rubber film expands at a uniform speed through the hydraulic system and applies uniform increasing pressure to the specimen. When the specimen is ruptured, the maximum pressure recorded by the system is the bursting strength value. The whole process conforms to the laws of energy conservation and fluid mechanics, which can be expressed as:
P = F/A
where P is the bursting strength, F is the force value at the moment of rupture, and A is the stress area of the specimen.
Measurement method
The standard measurement process includes four stages: specimen preparation, instrument calibration, test execution, and result analysis. Start by cutting the specimen to standard specifications to ensure no creases or damage. The specimen is placed between the fixtures and the specified clamping force is applied. The hydraulic system is activated to expand the rubber membrane at a standard rate until the specimen breaks. Each group of samples needs to be repeated many times, and the arithmetic average is taken as the final result after eliminating the outliers. The measurement process needs to strictly control the ambient temperature and humidity, usually requiring a temperature of 23°C±2°C and a relative humidity of 50%±5%.
Influencing factors
The fiber structure, thickness and density of the material itself are intrinsic factors that determine the bursting strength. External influences include specimen clamping pressure, rubber film properties, hydraulic ramp rate, and test environmental conditions. Insufficient fixture pressure may cause specimen slippage, while excessive pressure can cause premature rupture. The thickness and elasticity of the rubber film directly affect the pressure transfer efficiency. The incremental rate of the hydraulic system must comply with the relevant standards, and the rate deviation will cause the measurement results to deviate from the true value. The change of ambient temperature and humidity will cause the change of the moisture content of the material, which in turn will affect its mechanical properties.
Applications:
This instrument is used in the paper industry to assess the packaging strength of paper, cardboard, and corrugated boxes; The rupture resistance of composite film and flexible packaging was measured in the testing of packaging materials. In the textile field, the mechanical durability of non-woven fabrics, canvas and other materials is tested; It is used as an important tool for material access verification in quality inspection institutions. In addition, it is widely used in printed product strength assessment, industrial filter media testing, etc.
Key points of selection
When selecting an instrument, consider the measurement range and accuracy requirements to ensure that the strength range of the material to be measured is covered. The size of the fixture should meet the specifications of the specimen, and the common fixture aperture is 30.5 mm or 31.5 mm. The hydraulic system should have stable pressure increase control capabilities, and the resolution should not be less than 0.5% of the full scale. The equipment needs to support a variety of international standards, such as ISO 2758, ASTM D774, GB/T 1539, etc. The operation interface should be clear and intuitive, and the data output format should be easy to integrate into the laboratory information management system. Ease of maintenance and calibration intervals are also important considerations, and it is recommended to choose equipment with a modular design to reduce maintenance costs.