Containers such as bottles or jars are generally sealed by screw or lug-style closures. At various stages during the life cycle of such closures their performance can be characterised by a number of critical torques.
The original ‘Orbis’, a digital closure torque tester introduced by Mecmesin Limited in May 2003, has proved extremely popular for capturing the torques associated with the first opening, resealing, and re-opening of a closure. However the torque characteristics of tamper-evident closures are more complex. Therefore at Total 2004 Mecmesin will be launching an additional instrument especially designed for testing tamper-evident closures.
Consider, for example, the roll-on pilfer-proof (ROPP) aluminium cap used for sealing bottles of alcoholic drink including spirits, and increasingly, wine. Alternatively consider the aluminium lid and tamper-evident drop-ring sealing a jar of baby food, or the plastic closure sealing a PET soft drink bottle. When increasing release torque is applied to a closure, a peak torque value is associated with the point at which the closure begins to move. However in the case of TE-closures, torque must continue to be applied both to overcome friction and to apply tensile load to the ‘bridges’ connecting the closure to the tamper-evident ring. Eventually one bridge will fail, and a second (lower) torque peak will occur.
The Orbis-TE will capture both peaks. A single button push will then allow both values to be recorded on a PC or printer.