Volume 21, Issue 1 (January 1993)
More Rapid Edgewise Crush Test Methods
The use of paraffin wax to reinforce the loading edges of corrugated fiberboard edge-crush specimens requires that the specimens be reconditioned after waxing. The traditional practice employing a 24-h reconditioning period is a conservative approach based on the moisture response rate of corrugated containers. An interlaboratory study was conducted to determine the effect of reconditioning time on edgewise compressive strength of waxed specimen prepared by standard test methods. Results showed that reconditioning time can be reduced from 24 h to 2 h wish no significant change in test values. The results apply to flexible-beam and rigidplaten loading machines, but at conventional loading speeds, the flexible-beam machine yielded higher overall streagth values. Other tests were conducted to evaluate the performance of an edge-clamping fixture for use with unwaxed specimens. When tested with heavy basis weight materials, the fixture did not yield equivalent results compared to those obtained with lighter grade waxed apecimens.