Product design 3 chapter

E. C. Voutsas, P. Coutsikos and G. M. Kontogeorgis, In Computer Aided Property Estimation for Process and Product Design, Chapter 5, Elsevier, Amsterdam, 2004. 

Chapter 1 of this book starts with a detailed statement of the problem, as outlined above, focusing on the opportunities that exist in product design in order to reduce failure costs. This is followed by a review of the costs of quality in manufacturing... 

This chapter has attempted to describe briefly some properties of polymers relevant to product design in terms of molecular behaviour. For in depth consideration the reader should consult more detailed reviews (e.g. refs 4, 5 and 6). There also exist specialist monographs concerned with practical aspects of product design (e.g. refs 7 and 11). Mention should also be made of excellent booklets by materials suppliers (e.g. refs 2 and 8) concerned with design aspects. Some material manufactures now supply comprehensive data books backed by computer data bases for multi-point engineering data (e.g. ref. 12). 

Basics Creep data can be very useful to the designer. In the interest of sound design-procedure, the necessary long-term creep information should be obtained on the perspective specific plastic, under the conditions of product usage (Chapter 5, MECHANICAL PROPERTY, Long-Term Stress Relaxation/Creep). In addition to the creep data, a stress-strain diagram under similar conditions should be obtained. The combined information will provide the basis for calculating the predictability of the plastic performance. 

Designers unfamiliar with plastic products can use the suggested preliminary safety factor guidelines in Table 2-11. They provide for extreme safety. Any product designed with these guidelines in mind should conduct tests on the products themselves to relate the guidelines to actual performance (Chapter 4, RP PIPES, Stress-Strain Curves). With more experience, more-appropriate values will be developed targeting to use 1.5 to 2.5. After field service of... 

Design problems with the other conventional materials of construction are usually solved with the aid of textbooks or handbooks that refer the reader to data sheets where the characteristics of a specific material are listed. However, products designed with plastics involve some special considerations when using these textbooks or handbooks as reviewed in Chapter 2. 

The success of a specific technique will depend on whether, as a by-product of the technique, sizable stress levels in the plastic product may result. Guarding against potential stresses in the assembly is a very important aspect of complete product design. There are many techniques that provide assembling all kinds of products. Each have technical and/or cost advantages and limitations. Examples of a few are reviewed in this section with more information in Chapter 3, BASIC FEATURE and FEATURE INFLUENCING PERFORMANCE. 

This review concerns the long-term behavior of plastics when exposed to conditions that include continuous stresses, environment, excessive heat, abrasion, and continuous contact with liquids. This subject has been reviewed in Chapter 2 (LONG-TERM LOAD BEHAVIOR) but since it is a very important subject the review is continuing. Tests such as those outlined by ASTM D 2990 that describe in detail the specimen preparations and testing procedure are intended to produce consistency in observations and records by various manufacturers, so that they can be correlated to provide meaningful information to product designers. 

In light of the many types of behavior plastics that can manifest and the considerable effect this behavior can have on the performance of the finished product, it behooves designers to become familiar with specific behavior characteristics of each plastic considered for an application. Recognize potential problems. A major cause for problems is not of poor product design but instead that the processes operated outside of their required operating window. This subject will be reviewed latter in this Chapter under PROCESS CONTROL... 

The designer must be aware that as the degree of anisotropy increases, the number of constants or moduli required to describe the material increases with isotropic construction one could use the usual independent constants to describe the mechanical response of materials, namely, Young s modulus and Poisson s ratio (Chapter 2). With no prior experience or available data for a particular product design, uncertainty of material properties along with questionable applicability of the simple analysis techniques generally used require end use testing of molded products before final approval of its performance is determined. 

The whole topic of Life Cycle Assessment is dealt with in detail in Chapter 7. However, there are some important points about LCA as it relates to green product design. It is important to be able to compare different solutions, it is also important to be aware of the limitations of LCA. These include ... 

Plants are combinatorial chemists par excellence, and understanding the principles that relate enzyme structure to function will open up unlimited possibilities for the rational design of new enzymes to generate novel biologically active natural products (see Chapter by Noel et al.). 

In principle, problems related to chemical product design can be formulated and solved in many different ways. The objective here is to highlight some of those that have also been applied in the various product design case studies reported in chapters 2-15 of this book. These solution approaches may be classified under the following types ... 

Finally, chapter 15 proposes the development of a classification system for the available knowledge on chemical products that can serve as a guide in chemical product design, development and teaching. The chapter examines the nature of... 

This final Pures step is the last stage of manufacture for the API and may be considered as the API Product design step. It will be the focus of this chapter s case study, using the generic drug molecule Cimetidine as an example. 

I hope that this chapter provides a fitting introduction to the complex task of active pharmaceutical ingredient product design through ciystallization, and most importantly that it will stimulate work and encourage further growth in the application of thermodynamic models and optimization techniques in this area. 

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