To insure that the vertical strength of PET bottles is sufficient to meet minimum performance standards for vertical loading as might be encountered during bottle filling, capping and stacking of filled product.
Twelve test samples are individually placed under the test platen on an Instron test device. The downward movement of the load platen is initiated at a constant rate, and continues downward until the bottle’s resistance to loading peaks and the bottle loses column strength and deforms. The maximum load and deflection at max load are recorded and reported by the machine, and the failure location is added by the operator. Loads at other preset points may also be included in the recorded data.