Lloyd Instruments has added a new packaging test fixture to its range of specialised grips and accessories for the Plus range of materials testing machines
. This new fixture is designed to allow a pre-scored section of cardboard
to be bent through 90 degrees and the maximum force required to perform this bending to be measured. The fixture is supplied with NEXYGENPlus software
to compensate for any residual forces with moving the mechanism before the card sample is fitted.
The new accessory consists of a lower fixture with a rotating assembly, an upper cord mounting block and specialised software. Since there is a residual force required to move the fixture when there is no card sample fitted, this value must be removed from the test measurement to obtain the actual force required to bend the card. This is automatically carried out using the software supplied.
To perform the test, the cord is attached to the pulley on the lower fixture and any slack is removed by moving the crosshead. The forces required to move the fixture are measured and stored in a reference file. The cardboard
is then inserted into the fixture and the test repeated. The software automatically removes the residual force and displays a graph of "Test Load" against "Extension" or "Load" (total load including the load required to move the fixture) against "XHead". The software is configured to allow batch testing and to archive test results.