The Relevance of Drop Tester Accuracy

Abstract

Abstract ASTM D 5276-98 “Standard Test Method for Drop Test of Loaded Containers by Free Fall,” [1] was written as the general test specification for permitting free-fall drop tests for packaged products. One of the fundamental characteristics for drop testers used to perform ASTM D 5276 is that they must produce a flat drop with tolerance limit set at ±2 deg. For drops other than flat drops, such as edges and corners, tolerance limits of ±5 deg have been specified. Although most drop testers are calibrated during manufacturing, they are often not checked for accuracy at their lab locations. This is primarily due to the lack of a calibration standard. This paper investigates the importance of drop test accuracy and reports observations, measurements, and documentation of changes in acceleration and velocity change measured on a test specimen as it is subjected to drops with increasing deviation from the desired impact orientation. A statistical analysis of accelerations as impact orientations deviated is provided and statistical trends in the data as impact angles change are reported. The results suggested that the existing tolerances for performing drops within ±2 deg as recommended by ASTM D 5276 are acceptable for flat drops and the tolerances for performing edge and corner drops within ±5 deg are not acceptable as they can result in larger deviations as the offset is increased beyond ±2 deg.