Budynas-Nisbett:Shigley's I.Basics 1.Introduction to T©The McGraw-Hil Mechanical Engineering Mechanical Engineering Companies,2008 Design,Eighth Edition Design 12 Mechanical Engineering Desigr 1-6 Standards and Codes A standard is a set of specifications for parts,materials,or processes intended to achieve uniformity,efficiency,and a specified quality.One of the important purposes of a standard is to place a limit on the number of items in the specifications so as to provide a reasonable inventory of tooling,sizes,shapes,and varieties. A code is a set of specifications for the analysis,design,manufacture,and con- struction of something.The purpose of a code is to achieve a specified degree of safety, efficiency,and performance or quality.It is important to observe that safety codes do not imply absolute safery.In fact,absolute safety is impossible to obtain.Sometimes the unexpected event really does happen.Designing a building to withstand a 120 mi/h wind does not mean that the designers think a 140 mi/h wind is impossible;it simply means that they think it is highly improbable. All of the organizations and societies listed below have established specifications for standards and safety or design codes.The name of the organization provides a clue to the nature of the standard or code.Some of the standards and codes,as well as addresses,can be obtained in most technical libraries.The organizations of interest to mechanical engineers are: Aluminum Association (AA) American Gear Manufacturers Association (AGMA) American Institute of Steel Construction (AISC) American Iron and Steel Institute (AISI) American National Standards Institute(ANSI)> ASM International American Society of Mechanical Engineers(ASME) American Society of Testing and Materials(ASTM) American Welding Society (AWS) American Bearing Manufacturers Association (ABMA)' British Standards Institution(BSI) Industrial Fasteners Institute (IFI) Institution of Mechanical Engineers(I.Mech.E.) International Bureau of Weights and Measures (BIPM) International Standards Organization (ISO) National Institute for Standards and Technology (NIST) Society of Automotive Engineers(SAE) 1-7 Economics The consideration of cost plays such an important role in the design decision process that we could easily spend as much time in studying the cost factor as in the study of the entire subject of design.Here we introduce only a few general concepts and simple rules. SIn 1966 the American Standards Association (ASA)changed its name to the United States of America Standards Institute (USAS).Then,in 1969,the name was again changed,to American National Standards Institute,as shown above and as it is today.This means that you may occasionally find ANSI standards designated as ASA or USAS. "Formally American Society for Metals(ASM).Currently the acronym ASM is undefined. 7In 1993 the Anti-Friction Bearing Manufacturers Association(AFBMA)changed its name to the American Bearing Manufacturers Association(ABMA). Former National Bureau of Standards(NBS)Budynas−Nisbett: Shigley’s Mechanical Engineering Design, Eighth Edition I. Basics 1. Introduction to Mechanical Engineering Design 18 © The McGraw−Hill Companies, 2008 12 Mechanical Engineering Design 1–6 Standards and Codes A standard is a set of specifications for parts, materials, or processes intended to achieve uniformity, efficiency, and a specified quality. One of the important purposes of a standard is to place a limit on the number of items in the specifications so as to provide a reasonable inventory of tooling, sizes, shapes, and varieties. A code is a set of specifications for the analysis, design, manufacture, and con￾struction of something. The purpose of a code is to achieve a specified degree of safety, efficiency, and performance or quality. It is important to observe that safety codes do not imply absolute safety. In fact, absolute safety is impossible to obtain. Sometimes the unexpected event really does happen. Designing a building to withstand a 120 mi/h wind does not mean that the designers think a 140 mi/h wind is impossible; it simply means that they think it is highly improbable. All of the organizations and societies listed below have established specifications for standards and safety or design codes. The name of the organization provides a clue to the nature of the standard or code. Some of the standards and codes, as well as addresses, can be obtained in most technical libraries. The organizations of interest to mechanical engineers are: Aluminum Association (AA) American Gear Manufacturers Association (AGMA) American Institute of Steel Construction (AISC) American Iron and Steel Institute (AISI) American National Standards Institute (ANSI)5 ASM International6 American Society of Mechanical Engineers (ASME) American Society of Testing and Materials (ASTM) American Welding Society (AWS) American Bearing Manufacturers Association (ABMA)7 British Standards Institution (BSI) Industrial Fasteners Institute (IFI) Institution of Mechanical Engineers (I. Mech. E.) International Bureau of Weights and Measures (BIPM) International Standards Organization (ISO) National Institute for Standards and Technology (NIST)8 Society of Automotive Engineers (SAE) 1–7 Economics The consideration of cost plays such an important role in the design decision process that we could easily spend as much time in studying the cost factor as in the study of the entire subject of design. Here we introduce only a few general concepts and simple rules. 5 In 1966 the American Standards Association (ASA) changed its name to the United States of America Standards Institute (USAS). Then, in 1969, the name was again changed, to American National Standards Institute, as shown above and as it is today. This means that you may occasionally find ANSI standards designated as ASA or USAS. 6 Formally American Society for Metals (ASM). Currently the acronym ASM is undefined. 7 In 1993 the Anti-Friction Bearing Manufacturers Association (AFBMA) changed its name to the American Bearing Manufacturers Association (ABMA). 8 Former National Bureau of Standards (NBS)