The bursting resistance and bursting index of cardboard are common indicators for evaluating the strength and durability of cardboard.
Bursting Strength: Bursting Strength is a measure of the ability of cardboard to resist internal pressure and external forces to break. It refers to the maximum pressure value that cardboard can withstand under gradually increasing pressure. Bursting strength is usually expressed in terms of pressure per unit area, such as kilopascals (kPa) or pounds per square inch (psi).
Bursting Strength Index: Bursting Strength Index is the ratio between bursting strength and the base weight of the cardboard. It represents the bursting resistance of the cardboard per unit weight. Bursting Strength Index is calculated as: Bursting Strength Index = Bursting Strength/Base Weight. Usually expressed in kilopascals/gram (kPa/g) or pound force/pound (psi/lb).

Burst resistance and bursting index are usually measured using a Burst Tester, which applies pressure by gradually increasing the internal air pressure until the cardboard breaks. This determines the bursting resistance of the cardboard and calculates the bursting index.
Burst Resistance and Burst Resistance Index are very important for the quality control and evaluation of cardboard. Higher Burst Resistance and Burst Resistance Index means that the cardboard has better strength and durability, which can provide better performance when transporting, packaging and protecting products. These indicators are widely used in the cardboard manufacturing and packaging industries to ensure that the quality of the cardboard meets the requirements and meets the needs of specific applications.
