Frictional Resistance
Sliding friction measurement evaluates the coefficient of kinetic friction between corrugated board surfaces under specified normal loads. TAPPI T577 establishes this sliding resistance by dragging a sled across a horizontal specimen plane at a constant velocity. Packaging engineers apply the resulting friction values to predict box stability during high speed palletizing and automated warehousing operations.
Low surface friction causes stacks to destabilize on conveyor belts while excessive drag prevents proper automatic separation of flat blanks in high output folding carton machines.
Surface Friction
Coated substrates and untreated linerboards exhibit distinct frictional behaviors under identical normal forces due to binder variations and calendering treatments. TAPPI T577 quantitates these differences by recording the steady force required to maintain relative motion between mating faces. Corrugated converters monitor this response parameter to adjust wax applications and aqueous coating weights before running commercial orders through high speed case erectors.
Insufficient slip control leads to conveyor jams and feeder stalls on automated packaging lines, whereas overtreated surfaces trigger load shifting inside transport vehicles.
Tribological Boundary
Measurement precision depends entirely on sled mass and pull rate consistency because electrostatic charges and ambient humidity alter immediate contact mechanics. TAPPI T577 specifies precise conditioning parameters to eliminate moisture variations that distort surface topography readings during testing protocols. Laboratory technicians isolate the kinetic phase from initial static peak readings to isolate steady sliding behavior from surface adhesion anomalies.
Standardized test geometries ensure that corrugated board manufacturers produce packaging materials capable of maintaining secure friction profiles throughout global distribution chains.
