Bursting strength is widely used as a measure of resistance to rupture in many kinds of paper. The test is
relatively easy and inexpensive to make and appears to simulate some end use requirements.
Bursting strength of a material is defined as the maximum hydrostatic pressure required to produce rupture of the
material when a controlled and constantly increasing pressure is applied through a rubber diaphragm to a circular area, 30.5 mm (1.20 in.) diameter. The area of the material under test is initially flat and held rigidly at the circumference but is free to bulge during the test.
The test specimen, held between annular clamps, is subjected to an increasing pressure by a rubber diaphragm,
which is expanded by hydraulic pressure at a controlled rate, until the test specimen ruptures. The maximum pressure reading up to the rupture point is recorded as the bursting strength.
This method is designed to measure the maximum bursting strength of paper and paper products having a bursting strength of 50 kPa up to 1200 kPa (0.5 – 12.0 kg/cm2) and in the form of flat sheets of up to 0.6 mm (0.025 in.) thick.
It is not intended for use in testing corrugated, fiberboard, linerboard, or hardboards that tend to cut the thin rubber diaphragm of the bursting tester.