The objective of this research was to develop a test methodology for the evaluation of materials for possible use in cryogenic composite overwrapped pressure vessels (COPVs). This paper investigates various micromechanical and macromechanical techniques to test the interaction between fibers and resins. Uniaxial tension testing was performed at ambient and cryogenic temperatures on neat resin samples, straight-sided composite specimens, and NOL ring specimens. COPVs were constructed and burst tested to provide a performance comparison. Results show resins suitable for use at cryogenic conditions display a LN2 temperature elongation to failure greater than 2% and an ambient temperature elastic modulus less than 35 MPa. NOL rings were determined to be the preferred composite test method rather than straight-sided specimens. Mechanical performance of the NOL rings compares well with actual COPV performance.

The objective of this research was to develop a test methodology for the evaluation of materials for possible use in cryogenic composite overwrapped pressure vessels (COPVs). This paper investigates various micromechanical and macromechanical techniques to test the interaction between fibers and resins. Uniaxial tension testing was performed at ambient and cryogenic temperatures on neat resin samples, straight-sided composite specimens, and NOL ring specimens. COPVs were constructed and burst tested to provide a performance comparison. Results show resins suitable for use at cryogenic conditions display a LN2 temperature elongation to failure greater than 2% and an ambient temperature elastic modulus less than 35 MPa. NOL rings were determined to be the preferred composite test method rather than straight-sided specimens. Mechanical performance of the NOL rings compares well with actual COPV performance.

A bonding evaluation that investigated the cryogenic tensile strength of several different adhesives / resins was performed. The test materials consisted of 606 aluminum test pieces adhered to a wet-wound graphite laminate in order to simulate the bond created at the liner-composite interface of an aluminum-lined composite overwrapped pressure vessel. It was found that for cryogenic applications, a flexible, low modulus resin system must be used. Additionally, the samples prepared with a thin layer of cured resin - or prebond - performed significantly better than those without. It was found that it is critical that the prebond surface must have sufficient surface roughness prior to the bonding application. Also, the aluminum test pieces that were prepared using a surface etchant slightly outperformed those that were prepared with a grit blast surface finish and performed significantly better than those that had been scored using sand paper to achieve the desired surface finish. An additional impact investigation studied the post impact tensile strength of composite rings in a cryogenic environment. The composite rings were filament wound with several combinations of graphite and aramid fibers and were prepared with different resin systems. The rings were subjected to varying levels of Charpy impact damage and then pulled to failure in tension. It was found that the addition of elastic aramid fibers with the carbon fibers mitigates the overall impact damage and drastically improves the post-impact strength of the structure in a cryogenic environment.

With very few books adequately addressing ASME Boiler & Pressure Vessel Code, and other international code issues, Pressure Vessels: Design and Practice provides a comprehensive, in-depth guide on everything engineers need to know. With emphasis on the requirements of the ASME this consummate work examines the design of pressure vessel com

This, the second special topical conference on the properties of Non-Metallic Materials at Low Temperatures, was sponsored by the International Cryogenic Materials Conference Board. The potential for plastics materials in the field of cryogenics is vast and as yet only partly explored. In addition, many other materials, which qualify for the title non-metallic but are not 'plastics', have numerous possible outlets in low temperature technology. This conference aimed at providing a forum, whereby specialists from Industry, the Universities and from Government sponsored Institutions could assemble to discuss the extent of our current knowledge. As it transpired, the meeting was also to high light the considerable gaps that still exist in our fundamental understanding of the low temperature behaviour of these materials. On this theme, during the course of the conference, a reference was made to an almost forgotten quotation by Lord Kelvin, who said: "When you cannot measure what you are speaking about, when you cannot express in numbers, your knowledge is of a meagre and unsatisfactory kind; it may be the beginning of knowledge, but you have scarcely in your thoughts advanced to the stage of a science, whatever the matter be." This simple statement sums up the aims, objectives and hopefully the achievements of this conference. To discuss and disseminate the current knowledge on non-metallic materials in order that realistic predictions of in-service performance may be made.

The marine environment presents significant challenges for materials due to the potential for corrosion by salt water, extreme pressures when deeply submerged and high stresses arising from variable weather. Well-designed fibre-reinforced composites can perform effectively in the marine environment and are lightweight alternatives to metal components and more durable than wood. Marine Applications of Advanced Fibre-Reinforced Composites examines the technology, application and environmental considerations in choosing a fibre-reinforced composite system for use in marine structures. This book is divided into two parts. The chapters in Part One explore the manufacture, mechanical behavior and structural performance of marine composites, and also look at the testing of these composites and end of life environmental considerations. The chapters in Part Two then investigate the applications of marine composites, specifically for renewable energy devices, offshore oil and gas applications, rigging and sails. Underwater repair of marine composites is also reviewed. - Comprehensively examines all aspects of fibre-reinforced marine composites, including the latest advances in design, manufacturing methods and performance - Assesses the environmental impacts of using fibre-reinforced composites in marine environments, including end of life considerations - Reviews advanced fibre-reinforced composites for renewable energy devices, rigging, sail textiles, sail shape optimisation and offshore oil and gas applications

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The second edition of this very well-received book, which in itsfirst edition was entitled Postharvest Technology of Fruits andVegetables, has been welcomed by the community of postharvestphysiologists and technologists who found the first edition of suchgreat use. The book covers, in comprehensive detail, postharvestphysiology as it applies to postharvest quality, technologyrelating to maturity determination, harvesting, packaging,postharvest treatments, controlled atmosphere storage, ripening andtransportation on a very wide international range of fruits andvegetables. The new edition of this definitive work, which contains manyfull colour photographs, provides key practical andcommercially-oriented information of great use in helping to ensurethat fruit and vegetables reach the retailer in optimum condition,with the minimum of loss and spoilage. Fruits and vegetables, 2nd edition is essential readingforfruit and vegetable technologists, food scientists and foodtechnologists, agricultural scientists, commercial growers,shippers and warehousing operatives and personnel within packagingcompanies. Researchers and upper level students in food science,food technology, plant and agricultural sciences will find a greatdeal of use within this landmark book. All libraries in researchestablishments and universities where these subjects are studiedand taught should have copies readily available for users. A. K. Thompson was formerly Professor and head of PostharvestTechnology, Silsoe College, UK.

Industrial high pressure processes open the door to many reactions that are not possible under 'normal' conditions. These are to be found in such different areas as polymerization, catalytic reactions, separations, oil and gas recovery, food processing, biocatalysis and more. The most famous high pressure process is the so-called Haber-Bosch process used for fertilizers and which was awarded a Nobel prize. Following an introduction on historical development, the current state, and future trends, this timely and comprehensive publication goes on to describe different industrial processes, including methanol and other catalytic syntheses, polymerization and renewable energy processes, before covering safety and equipment issues. With its excellent choice of industrial contributions, this handbook offers high quality information not found elsewhere, making it invaluable reading for a broad and interdisciplinary audience.