ME 111 Engineering GraphicsVeershetty GumtapureAssistant ProfessorMechanical EngineeringNITK Surathkal

Graphics as a language ?

Graphics as a language?Language is the medium of communication.Graphics means drawingsGraphic language is the mode of communication by means of sketches. Oldest form of communication among human.Prehistoric man used a stick to scratch out a message in the sandEarly Egyptians used pictures made using paint and brush

Graphics as a language- ExampleTraffic symbols

Graphics is a Universal language

Graphics as a language- Example

Graphics is a Universal language

Engineering GraphicsThe representation of an object containing details like shape, size, etc.,is a visual means to develop ideas and convey designs in a technical format.is the dominant means to communication among engineers in industry.

Need for Engineering GraphicsIn the era of globalizationInterpreting information from drawings is an important skill. Engineers and architects must be able to look at a set of plans and mentally picture the shapes of objects.

GRAPHICS LANGUAGE

1. Try to write a description of this object.2. Test your written description by having someone attempt to make a sketch from your description.Effectiveness of Graphics LanguageThe word languages are inadequate for describing the size, shape and features completely as well as concisely.You can easily understand that

Graphic language in engineering application uselines to represent the surfaces, edges and contours of objects.Composition of Graphic Language

Freehand drawing The lines are sketched without using instruments other than pencils and erasers.

Instrument drawing Instruments are used to draw straight lines, circles, and curves concisely and accurately. Thus, the drawings are usually made to scale.

Computer drawing The drawings are usually made by commercial software such as AutoCAD, solid works etc.

Engineering Drawing

Elements of Engineering DrawingEngineering drawing are made up of graphics languageand word language.

Basic Line Types Types of LinesAppearanceName accordingto applicationNOTE : We will learn other types of line in later chapters.

Visible lines represent features that can be seen in the current viewMeaning of LinesHidden lines represent features that can not be seen in the current viewCenter line represents symmetry, path of motion, centers of circles, axis of axisymmetrical partsDimension and Extension lines indicate the sizes and location of features on a drawing

Example : Line conventions in engineering drawing

Multiview Drawing

Multiview Drawing

Drawing SheetTrimmed paper ofa size A0 ~ A4.Standard sheet size- Bureau of Indian Standards (BIS) A4 210 x 297A3 297 x 420A2 420 x 594A1 594 x 841A0 841 x 1189A4A3A2A1A0(Dimensions in millimeters)

Drawing spaceDrawingspaceTitle blockBorder lines1. Type X (A0~A4)2. Type Y (A4 only)Title block

Traditional Drawing Tools

DRAWING TOOLS

1. Mini-Drafter2. Set SquaresDRAWING TOOLS

3. Adhesive Tape4. Pencils2H or HB for thick line4H for thin lineDRAWING TOOLS

5. Sandpaper6. CompassDRAWING TOOLS

7. Pencil Eraser8. Erasing ShieldDRAWING TOOLS

9. Circle Template10. Tissue paperDRAWING TOOLS

11. Sharpener12. Clean paperDRAWING TOOLS

ABCDEFGHIJKLMNOPQRSTUVWXYZABCDEFGHIJKLMNOPQRSTUVWXYZABCDEFABCDEFGHIJKLMNOPQRSTUVWXYZABCDEFGHIJKLMNOPQRSTUVWXYZABCDEFLettering

Text on DrawingsText on engineering drawing is used :Thus, it must be written with

ExamplePlacement of the text on drawing

Basic StrokesStraightSlantedCurvedHorizontal1123Examples : Application of basic strokeI letterA letter123456B letter

Suggested Strokes SequenceStraight linelettersCurved linelettersCurved lineletters &NumeralsUpper-case letters & Numerals

The text s body height is about 2/3 the height of a capital letter.Suggested Strokes SequenceLower-case letters

Stroke SequenceILTFEH

VXWStroke Sequence

NMKZYAStroke Sequence4

OQCGStroke Sequence

DUPBRJStroke Sequence12

5Stroke Sequence7

Leave the space between words equal to the space requires for writing a letter O. ExampleSentence CompositionALLDIMENSIONSAREINMILLIMETERSOOOOUNLESSOTHERWISESPECIFIED.O

DimensioningA dimensioned drawing should provide all the information necessary for a finished product or part to be manufactured. An example dimension is shown below.

Dimensions are always drawn using continuous thin lines. Two projection lines indicate where the dimension starts and finishes. Projection lines do not touch the object and are drawn perpendicular to the element you are dimensioning.All dimensions less than 1 should have a leading zero. i.e. .35 should be written as 0.35

Aligned System of Dimensioning

Unidirectional System of Dimensioning

Types of Arrowheads

Dimensioning according to space availability

Dimensioning according to space availability

Application of Dimension lines

Dimension according to the rule

Dimension according to the rule

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