ASME Y14.100:2004 pdf download Engineering Drawing Practices
4.19 Graphic Symbols, Designations, LetterSymbolsand Abbreviations
Graphic symbols, designations, letter symbols, andabbreviations used on engineering drawings and associated lists shall be in accordance with this Standard andthe standards indicated below in paras. 4.19.1 through4.19.12.Where graphic symbols,designations, lettersymbols, and abbreviations are not covered by the stan.dards indicated in paras.419.1 through 4.19.12,theymay be used proided they are explained on each draw-ing or referenced to an explanatory document. Whennonstandard graphic symbols, designations, letter sym-bols, and abbreviations are used repeatedly thev shouldbe forwarded to ASME for possible inclusion in therespective standard.
4.19.1 Graphic Symbols for Electrical and ElectronicsDiagrams Graphic symbols for electrical and electronicsdiagrams shall be in accordance with IEEE 315 and Supplement ANSI/1EEE 315a
4.19.2 Graphic Symbols for Logic Functions. Graphicsymbols for logic functions shall be in accordance withANSI/IEEE 91 and Supplement IEEE 9la.
4.19,3 Graphic Symbols for Flowchart Diagrams.Flowchart symbols for use in information processingshall be in accordance with ANST/AITM MS4
4.19.4 Mechanical and Piping Symbols.Mechanicaland piping symbols shall be in accordance with ASTMF 1000,ASTM F 856,or ASME Y32.2.6, as applicable.
4.195 Graphic Symbols for Aircraft Hydraulic andPneumatic Systems.Graphic symbols for aircrafthydraulic and pneumatic svstems diagrams shall be inaccordance with SAE AS 1290.
4.196 Welding Symbols. Welding symbols shall bein accordance with ANSI/AWS A24, together withterms and definitions in accordance with ANSI/AWSA3.0.
4.19.7 Nondestructive Testing Symbols. Nondestructive testing sybols shall be indicated in accordanoewith ANSI/AWS A24.
4.19.8 Graphic Symbols for Fluid Power DiagramsGraphic symbols for fluid diagrams shall be in accor-dance with ANSI Y3210.
4.19.9 Reference Designations for Electrical and Electronics Parts and Equipment. Referenoe designations foelectrical and electronics parts and equipment shall beassigned in accordance with ANSI/IEEE 200IEEE 315and Supplement ANSI/IEEE 315a.
4.19.10 Letter Symbols. When used, letter symbolson engineering drawings shall be in accordance withANSI/IEEE 260.1 and ANSI/IEEE 280.
4.19.11 Mathematical Signs and Symbols.Mathematical signs and symbols shall be in accordance withANSI/IEEE 260.3.
4.1912 Abbreviations Abbreviations shall be inaccordance with ASE Y14.38
4.20 Logic Circuit Diagrams
Logic circuit diagrams shall be in accordance withANSI/IEEE 991.
4.21 Printed Boards
4.211 Printed Board Drawings.Printed board draw-ings shall be in accordance with the requirements ofIPCD-325 and IPC 2221, as applicable.
4.21.2 Printed Board Description in Digital Form.When printed board descriptions are in digital form, thedescription and form shall be in accordance with ANSI/IPC D-350.
4.22 Digital Data
Engineering drawings prepared by other than manualmeans (such as computer-generated drawings) shallprovide all of the information required by the particulardrawing type or level of design disclosure. Variationsfrom the requirements as specified herein to accommodate document preparation will be acceptable so longas these variations meet the requirements relative to theinformation contents.
4.23 Scale
Scale expresses the ratio of the object size as drawnto its full size. Drawings shall be drawn to a scale thatdepicts all details of the item clearly and accurately.except as noted in para. 4.23.3
4.23.1 Selection of Scale. Drawings should show anobject or assembly to full scale. When full scale is notpracticable,drawings may be prepared to reduced orenlarged scale. It is desirable, whenever practicable, thatdetail drawings be prepared to the same scale as perti-nent assembly drawings.