Shock Transmissibility of a Palletized Load Caused by Forklift Truck Handling

摘要

Palletizing individual shipping containers for distribution is a common practice. The movement of these unitized loads through distribution exposes them to physical (shock, vibration and compression) and ambient (temperature and humidity) hazards. Shocks may occur due to drops or impacts during mechanical handling of these units. Millions of dollars in damage occurs due to loss of product from improper forklift handling. Fresh produce in particular is highly susceptible to damage which leaves the product unsalable, leading to its eventual disposal. Though there are several industry accepted test procedures that accommodate the validation of palletized loads against the anticipated distribution scenario, none provide an understanding of the shocks experienced by products within the shippers. This paper provides details of a preliminary study undertaken towards understanding the transmissibility of shocks originating from mechanical handling of palletized loads to the product carried within the shippers. The study utilized data recorders to analyze a variety of standardized shock tests commonly prescribed towards the simulation of distribution as published by ASTM and ISTA. Peak acceleration values were recorded at different locations within palletized loads. The transmitted shocks were observed to increase proportionally with increasing velocities of impact. Regardless of direction of shock input, the centrally located shippers tend to experience attenuated shocks. Interlock patterns tend to transmit higher shocks in comparison to the column pallet pattern.