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The use of loosely packed items in rigid or semi-rigid containers is widespread. These packages are very often handled by high speed equipment and put in different environmental conditions which includes the possibility of mechanical damage, due to shock, impact and compression. So care must be taken that damage does not occur to both package and contents. The development of analytical and simulation techniques for investigating the dynamic behaviour of a package subject to handling and distribution hazards is becoming more possible by the use of a wide range of available software. The modelling of the dynamic behaviour of packaging systems during handling and transport is achieved by mathematical analysis where possible and supported by computer simulation. The analysis was carried out for a range of body properties in order to test the results against experimental data. Investigations into the applied package force/motion and subsequent package impact and deformation were carried out with a view to gaining an understanding of the forces involved. The dynamic analysis was undertaken using commercially available software but it is necessary to develop special techniques to enable it to be applied to this type of problem. Corrugated fibreboard containers subjected to internal and external loading will be subjected to stress, strain, deflection, and buckling to side panels. A Finite Element method of analysis of the panel was developed. The reaction of the panel to loading can be observed by means of this method. The failure of the container due to the loading can be predicted and the variability of the material and the panel can be changed arbitrarily to test and analyze different packaging designs. Corrugated fibreboard and container elements were treated as engineering structures so the engineering concepts of stress, stain, equilibrium and compatibility could be applied. A Finite Element method using the ANSYS code made it possible to analyze the structure behaviour and helps to partly solve the design optimization process for a corrugated container. The project includes four main aspects: Finite Element analysis of the corrugated fibreboard and container elements subjected to internal and external load. 2 Corrugated fibreboard material tests. 3 Modelling of a package-contents system 4 Simulation of the products-cushion-package system The main area of research that is described in this thesis is concerned with developing the analytical and experimental methods to model and analyze the behaviour of packaging. This enables the size of the cushioning structure to be minimized and the cushioning and package material to be selected appropriately. The final stage of this project was to develop the techniques for the prediction of the susceptibility to damage to packaging systems particularly during the design stage, and to develop a comprehensive technique for the design and justification of the package system.

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For glass bottles to compete with plastic ones they need to be very much lighter. As their present weight is often constrained by their current strength, the glass they are made from needs to be very much stronger. In its virgin state glass is very strong, but handling bottles during manufacture introduces minute flaws, lowering their strength considerably. The aim of this work has been to gain a greater understanding of the meclianisms of thermal and mechanical damage and so to improve existing, and develop new hot glass handling materials which will reduce the amount of damage to the glass during hot-end handling To help gain an understanding of the interaction between thermal and mechanical damage mathematical modelling using finite difference techniques was utilised. Experimental investigations of how controlled contact, including thermal shock, weakened high strength glass were also undertaken. It was concluded from these investigations that the nearest to the ideal a real hot glass handling material could approach would be a material which produces mechanical damage which is limited to such a size that the thermal stresses produced by that material do not exacerbate the damage. A dimensionlessg roup was identified which helped to assessif a material had a selection of material properties which render it a likely hot glass handling material. Zirconium and Titanium were identified as possible hot glass handling materials. Carbon based materials proved to be the best handling materials but they have a limited life as they suffer oxidation in use. The oxidation resistance of various Carbon based materials was investigated with thermal gravimetric analysis and a test was designed to assess the strength retention of laminated Carbon-Carbon composites. Various coatings were developed to increase the life of existing hot glass handling materials. A Tit anium /graphite composite was developed in which the Titanium acted as an oxidation resistant skeleton and the graphite provided optimum glass handling ability.

No description available.

No description available.

Although glass containers are an everyday item the process responsible for their production is not scientifically understood. Developments have occurred slowly over many years, mostly on a trial and error basis and in response to economic pressures. The narrow neck press and blow (NNPB) process has evolved in recent years as a result of attempts to reduce container weight. The fundamental component of the NNPB process is the plunger which is responsible for the initiation of the cavity and control of glass distribution within the container. The NNPB plunger functions as a form tool and as a heat exchanger, thus requiring a carefully selected range of properties. The Engineer responsible for tooling selection and operation has a limited resource of scientific knowledge to enable the performance of the process to be optimised. The current NNPB plunger is subject to high rates of wear and is directly responsible for product defects, thermal instability and limits process speed. The work presented here is a scientific study of current NNPB plunger technology. The plunger has been investigated in relation to the requirements of the glass container forming process. The materials used have been examined, before and after use and their wear modes explained. The thermal properties of the plunger have, as far as is possible, been examined during the forming cycle. When combined with results from the characterisation of transformations occurring in the material, during its service life, operational requirements have been explained. The ability of the NNPB plunger to remove heat from the glass has been investigated, and has illustrated significant deficiencies in the current arrangement. Details are given as to how these deficiencies may be overcome to enable the Engineer to regain control of the process. As a result of the study many phenomena exhibited by the NNPB plunger are now understood and may be related to the performance of the process.

Adhesion aspects of laminated aluminium/polyester systems have been studied before and after mechanical deformation. The work has been carried out in collaboration with a producer of beverage cans, and the reasons for the adhesion reduction observed during the deep drawing and wall ironing process has provided the focal point for the work. Laminates were manufactured from commercial polyester film and commercially anodised (2 types) or chromium phosphated aluminium coil stock. The morphology of the pretreated aluminium surfaces has been investigated by using scanning electron microscopy. The chemical composition and the composition variation with depth of the pretreated aluminium surfaces have been studied by XPS sputter depth profiling. It is found that the CP and PAAI, PAAII pretreatments have reduced the amount of magnesium in the top layer of aluminium surfaces. An intimate contact between the polyester film and the aluminium substrate of the laminates and the thicknesses of the pretreated layers have been observed by cross- sectional TEM following sample preparation by chemical sample thinning and microtoming. Based on angle resolved XPS and SIMS investigation, the locus of failure of the can systems produced from the CP and PAAI treated aluminium has been defined as within the polyester film but very near the interface. The thickness of the residual polyester overlayers has been estimated. A peel test has been used to evaluate the adhesion level of the cans. The order of the adhesion level of the cans produced from different surface pretreated aluminium has been found to be; PAAII > CP > PAAI. Chemical exposure methods have been established to make the investigation of interfacial surfaces of the laminates possible by SEM. A shear lag analysis has been carried out to demonstrate the mechanical deformation behaviour of the laminates during the deep drawing and wall ironing process. A relationship between the thickness of the pretreated layer and the fragment size has been proposed. It is found that the pretreated layer fragment characteristics is very important. Fine and uniformly distributed fragments with small separation distance in the aluminium substrate of the cans contribute to the adhesion level through crack pinning effect. A comprehensive model for adhesion loss during deep drawing and wall ironing process has been proposed.

No description available.

No description available.