Design Procedure for Plastics Parts Function, Material, Geometry, Test

Design Procedure for Plastics Parts Function, Material, Geometry, Test 

This chapter will outline the procedure for the design of plastics parts and give the methods of sizing, material selection, cost consideration, design life, performance evaluation, and testing. The monitoring of quality will be indicated to insure performance. All the basic information and approaches have been covered, thus this chapter is a synthesis of previous discussions. 

Still permits a wide range of design choices as to material and structure and shape but they would be limited to those normally used in a library environment. The more accurately and completely the function is defined, the more restricted are the design possibilities and the more detailed the specifications for the function. 

The next step in the design procedure is to select the materials. The considerations are the physical properties, tensile and compressive strength, impact properties, temperature resistance, differential expansion, environmental resistance, stiffness, and the dynamic properties. In this example, the only factor of major concern is the long-term stiffness since this is a statically loaded part with minimum heat and environmental exposure. While some degree of impact strength is desirable to take occasional abuse, the part is not really subjected to any significant impacts. 

Using several materials such as polypropylene, glass-filled polystyrene, and styrene molded structural foam which is a natural sandwich panel material, the design procedure follows to determine the 

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