Performance requirements chapter

Materials used such as stifFer plastics can reduce hysteresis heating. Crystalline TPs for example (the popularly used acetal and nylon) can be stiffened by 25 to 50% with the addition of fillers and reinforcements. Others used include ABS, polycarbonates, polysulfones, phenylene oxides, polyurethanes, and thermoplastic polyesters. Additives, fillers, and reinforcements are used in plastics gears to meet different performance requirements (Chapter 1), Examples include glass fiber for added strength, and fibers, beads, and powders for reduced thermal expansion and improved dimensional stability. Other materials, such as molybdenum disulfide, polytetrafluoroethylene (PTFE), and silicones, may be added as lubricants to improve wear resistance. 

In this evaluation what is being presented appears unwanted complications that are not needed for such a simple design. However when going into a complicated design one can apply this basic approach to the more complicated designs. Thus the next move is to produce prototypes to ensure that the product will meet performance requirements (Chapters 2... 

As reviewed throughout this book one must determine what measures were taken to evaluate the materials. Carefully study the test results and test methods that are employed in obtaining these properties and their interpretation for application purposes (Chapter 5), and finally determine the fine details of use conditions to establish the suitability of a plastic material for the intended product. It is easily accomplished to determine the plastic to be used but requires familiarity with the test results being evaluated and behavior of plastics to meet your performance requirements. 

Plastic films represent the largest worldwide market for plastics with practically all extruded (6). They are used to meet different performance requirements particularly for its major packaging market. Worldwide just for biaxial oriented (Chapter 8) polypropylene consumption is about 5 /2 billion lb. Their use includes tape, food, tobacco, and confectionery. Thermoforming film (and extruded sheets) is a major processing technique producing all kinds of products. 

There are conditions during the fabrication of plastic products that ensure meeting product performance requirements. However there are also constraints as reviewed in Chapter 8. 

With the growth of plastic use in containers and packages, requirements to make them more compatible or useful resulted in new developments occuring and continue to occur. The two major approaches for providing permeability resistance in plastic containers involve chemically modifying the plastics surfaces and, more important from a marketing standpoint, the use of barrier plastics with nonbarrier types to meet cost-to-performance requirements. This is achieved through coextrusion, coinjection, corotation, and other such processes (Chapter 8). 

Some plastics can be worked by many different processes, but others require a specific process (Fig. 10-9). Process selection can take place before material selection, when a range of materials may be available, or made first to meet performance requirements and only then have the applicable process or processes chosen. (Chapter 7, SELECTING PLASTIC and Chapter 8, SELECTING PROCESS) Usually, in the latter situation only one special process can be used to provide the best performance-to-cost advantages. A particular design group may have its own processing capabilities. Unfortunately, some operations use just whatever equipment is available. This situation could either be very unprofitable, limit profitability, or restrict product... 

In a bubble-column reactor for a gas-liquid reaction, Figure 24.1(e), gas enters the bottom of the vessel, is dispersed as bubbles, and flows upward, countercurrent to the flow of liquid. We assume the gas bubbles are in PF and the liquid is in BMF, although nonideal flow models (Chapter 19) may be used as required. The fluids are not mechanically agitated. The design of the reactor for a specified performance requires, among other things, determination of the height and diameter. 

Structural performance requirements for blast resistant design include limits imposed on member deflections, story drifts and damage tolerance levels. Conventional serviceability requirements are not applicable for the one time severe blast loading conditions. See Chapter 5 for additional information. 

The blast resistance of conventional doors is generally limited by the rebound capacity in the unseating direction. A conventional unreinforced hollow metal door with a cylindrical latch may be adequate to withstand a rebound force of 50 psf (2.4 kPa). Door with a mortised latch may be adequate for a rebound force of 100 psf (4.8 kPa). If the blast pressure exceeds this, other alternatives may be considered. These include placing interior or externa barrier walls, or installation of blast resistant doors and frames. Unlike conventional doors, blast doors are typically provided as a complete assembly including the door, frame, hardware and accessories. This is because all the components are dependent on each other to provide the overall blast resistance. Refer to Chapter 9 for performance requirements and design details for blast resistant doors. 

Key performance requirements for composite assay methods are provided in ICH guidelines Q2A, Q2B, Q3A and Q3B. ICH Guidelines are discussed further in Chapter 10. To summarize briefly, and with some generalizations, HPLC methods applicable to the analysis of DS synthesized via the commercial route and final formulations of DP, should meet the following criteria ... 

The API SJ motor oil test (adapted in 1996) and ILSAC GF-2 are comprised of a set of engine tests for defining minimum oil performance requirements. These tests are as follows bearing wear and corrosion (Sequence L-38), valve corrosion (Sequence II-D), sludge formation (Sequence III-E), degradation wear products (Sequence V-E), and fuel economy (Sequence VI-A), (Lakes, 1999). For abbreviations see Chapter 8. 

In maximizing performance, or at least meeting performance requirements of extruded plastics as well as minimizing cost to extrude products it is important to understand the processing behavior of the different plastics. In producing the different extruded products certain plastics can be used. An understanding of factors such as their rheological to decomposition behaviors as well as problems that can develop provide information that will make it easier to extrude products (Chapters 1, 2, 3, and other chapters). 

Reinforced RIM (RRIM) elastomers are used. By the addition of reinforcing fillers such as milled glass fiber, glass flake, or mineral fillers in the polyurethane or short to long glass fiber in preforms, fabric, or mat forms placed in the mold cavity, the properties of the material can be altered to meet high performance requirements of the part (Chapter 15). The reinforced elastomers are used to increase flexural modulus, improve thermal properties, and improve dimensional stability.267... 

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