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Free-fall tests are generally conducted as the last verification step in the cushioning package design process. However, in practice, design requirements are often not met in a single pass of verification testing and two or three repetitions of the ‘design and test’ steps are typically required, necessitating significant amounts of labour and material resources. Therefore, if the product is a prototype or an expensive product, repeated testing is difficult due to the limited quantity or high cost of samples. For such cases, a new method called the ‘hybrid free-fall test’ is proposed for preventing damage to a tested product. Using this method, the peak shock acceleration occurring during a target (high) free-fall height test can be predicted using the data from a safety free-fall height test. The packaged product is usually conceptually modelled to assist in packaging research, and so far, several physical models have been proposed. In this study, we review one such model, the friction-viscous damping model, and propose a new prediction method for the hybrid free-fall test in which a reconsidered friction-viscous damping model is applied. Furthermore, we used expanded polyethylene and structured corrugated sleeve cushioning materials for verification and considered an effective physical model for each cushioning material.

To verify the cushion performance of transport packaging, two traditional drop test methods – free fall and controlled shock tests – and a traditional simulation method are often used. However, it is difficult to assure the safety of a test product when the traditional drop test method is applied, and results from the traditional simulation method are not sufficiently accurate to be used to test packaging material. Therefore, we propose a new test method called ‘the hybrid drop test’ by integrating the traditional drop test and simulation methods. The hybrid drop test ensures the safety of the test product and improves test efficiency. The results of the verification test show that this new drop test method can be applied to test the cushion performance of pulp mould transport packaging. Copyright © 2013 John Wiley & Sons, Ltd.

To investigate the influence of different combinations of peak acceleration and velocity change on repetitive-shock-induced damages leading to cumulative fatigue in products, we performed drop tests of products packaged similar to those in actual transportation, from several different drop heights and with two kinds of cushioning materials. The damage boundary curves (DBCs), corresponding to the degree of damage per shock, were prepared to investigate the possibility of DBC application for the evaluation of repetitive-shock-induced damage. The drop test showed erroneous results, when predicting repetitive-shock-induced damage, if based only on the relationship between peak acceleration and the degree of damage per shock, as have been carried out in previously reported studies. In our study, the DBCs for a specific degree of damage per shock were prepared, although the ranges of the peak acceleration and velocity change were limited. Preparation of DBC corresponding to the degree of damage per shock, as determined from the peak acceleration and velocity change beforehand, may increase the accuracy of predicting repetitive-shock-induced damage to products from cumulative fatigue. Copyright © 2013 John Wiley & Sons, Ltd.

In this study, the reliability of the traditional equivalent drop theory for transport packaging was experimentally evaluated, and a new physical model that considers the factor of friction was proposed. Using this new model, mathematical shock response equations of a shock test and a test at free-fall were deduced. In addition, a correcting condition was reached. To let the equivalent free-fall height be exactly equivalent, a new friction equivalent drop theory was proposed. This theory not only significantly reduces experimental errors and improves the accuracy of equivalent experiments but also provides a new theoretical basis for experimental analysis of structural cushioning materials. Copyright © 2012 John Wiley & Sons, Ltd.

Moulded pulp has been used as an alternative to plastic in certain packaging applications, but some problems in the production system lead to higher costs including energy consumption. Industry tends to operate on the basis of experience rather than through scientific evaluation and systematic design methods. The research aims at detecting the problems in the production system by a multidimensional life cycle assessment (MLCA) with transparent analysis. The MLCA measures the performance of the moulded pulp production system with regard to technical, economic and environmental aspects and produces quantitative results (in monetary units), and finally indicates the overall efficiency of the production system using a sustainability index (SI). A life cycle impact assessment method based on endpoint modelling (LIME) is mainly adopted in the MLCA. Three existing moulded pulp production systems for industrial packaging in China were assessed in this study. The results show that the main environmental impacts Of the three production systems are the atmospheric emissions and landfill waste; the drying stage in the production systems, which is dominated by consumption of resources and environmental impacts, is the key to controlling costs; steam should be the first preferred heat source in the drying process for achieving sustainability in the moulded pulp production system. The optimum for the three cases is identified by calculating the newly developed SI. The MLCA approach can be used to assist in identifying potential improvements and practical new packaging designs. Copyright (C) 2009 John Wiley & Sons, Ltd.