Design Of Test Systems And Vibration Performance EPE Buffer Drop Impact

Shock and vibration during transportation are the main cause of packagedamage. Traditionally, the product was modeled as a simple lumped mass,neglecting the complex configuration of most products. This will cause thetheory inconsistent with the actual. The cushion and isolation characteristics ofEPE (Expandable Polyethylene) were studied, viscoelastic polynomial tangentconstitutive relation of EPE were established.A set of drop impact testing machine was developed based on the classicaltheory of cushion packaging dynamics in the second chapter. The interference ofrandom signal was effectively reduced by a variety of digital filtering technology.The system can record the acceleration signal of impact process. By processingthe data, the drop process characteristic was recorded. It provides a basis forfurther study on the constitutive model of cushion materials.Drop cushioning characteristic of EPE was studied with aboveexperimental system in the third chapter. Based on the cushioning viscoelastictheory, the drop cushioning constitutive model was established. A nonlinearpackaging model with two degree of freedom containing a critical componentwas established, and the impact response of cushioning system made of EPE anditems with the critical component was studied numerically. It is shown that thedamage boundary of cushion packaging products is like the symbol "√". Theparameter λ is introduced to the ratio between the cushion economy and thesafety of a critical component.In comparison, the isolation constitutive model of EPE was studied in thefourth chapter. The transport model was established based on quarter. Thedynamic response of the vehicle transport packaging products was studied. It isshown that the structural dimension of EPE pad has great effect on the responseof critical component. Best of structural dimensions concentrated in an range ofdamage boundary. Appropriately increasing the pad area can effectively enhancethe protective ability of cushioning packaging products. This paper also studied the cushioning impact and cushioning vibrationisolation of transportation, which covers the main process of packaging productlogistics. The conclusions developed in this paper provide a theoretical basis andexperimental methods to accurate design and effect analysis of vibrationisolators.