Ply bond testing is used to determine the internal strength of paper and board materials. The ply bond test measures the energy required to delaminate a multiply board structure. Results are quoted in mJ.
Scott internal bond strength testing is included in Smithers Pira's Paper Proficiency Service.
Standards and Accreditation
Our testing is performed using a Scott plybond tester to the Tappi standard T833.
Smithers Pira Liner Cleavage Test
A drawback of the Scott ply bond test is that it often causes delamination towards the centre of the board structure, and not always at the weakest ply bond.
To assess the liner strength of carton boards and corrugated liners for various packaging applications including machine carton erection, Smithers Pira have developed a liner cleavage test which measures the force to pull a rod through the weakest ply bond.