Presentation on theme: "Overview of an Engineering Drawing"— Presentation transcript:
1Overview of an Engineering Drawing University of PalestineCollege of Engineering & Urban PlanningFirst LevelEngineering DrawingLecture 1Overview of an Engineering DrawingLecturer:Eng. Eman Al.SwaityEng.Heba Hamad
4Effectiveness of Graphics Language 1. Try to write a description ofthis object.2. Test your written descriptionby having someone attempt to make a sketch from yourdescription.You can easily understand that …The word languages are inadequate for describing the size, shape and features completely as well as concisely.
5Composition of Graphic Language Graphic language in “engineering application” uselines to represent the surfaces, edges and contours of objects.The language is known as “drawing” or “drafting” .A drawing can be done using freehand, instruments or computer methods.
6Freehand drawing Example The lines are sketched without using instruments other than pencils and erasers.Example
7Instrument drawing Example Instruments are used to draw straight lines, circles, and curves concisely and accurately. Thus, the drawings are usually made to scale.Example
8Computer drawing Example The drawings are usually made by commercial software such as AutoCAD, solid works etc.Example
10Elements of Engineering Drawing Engineering drawing are made up of graphics languageand word language.GraphicslanguageDescribe a shape (mainly).WordlanguageDescribe size, location and specification of the object.
11Basic Knowledge for Drafting GraphicslanguageWordlanguageLinetypesGeometricconstructionProjectionmethodLettering
13IntroductionStandards are set of rules that govern how technical drawings are represented.Drawing standards are used so that drawings conveythe same meaning to everyone who reads them.
14Standard Code มอก. สำนักงานมาตรฐานผลิตภัณฑ์อุตสาหกรรม Country Code Full nameมอก.สำนักงานมาตรฐานผลิตภัณฑ์อุตสาหกรรมThailandANSIAmerican National Standard InstituteUSAJISJapanese Industrial StandardJapanBSBritish StandardUKASAustralian StandardAustraliaDeutsches Institut für NormungDINGermanyISOInternational Standards Organization
16Partial List of Drawing Standards Code numberContentsJIS Z Sizes and Format of DrawingsJIS Z Line ConventionsJIS Z LetteringJIS Z ScalesJIS Z Projection methodsJIS Z Presentation of Views and SectionsJIS Z Dimensioning
17Drawing Sheet Trimmed paper of a size A0 ~ A4. Standard sheet size (JIS)A x 297A x 420A x 594A x 841A x 1189A2A1(Dimensions in millimeters)A0Note: A0 paper area is 1 m2
18Orientation of drawing sheet 1. Type X (A0~A4)2. Type Y (A4 only)cddcDrawingspaceBorderlinesDrawing spaceTitle blockTitle blockcSheet size c (min) d (min)AAAAA
19Drawing ScalesLength, sizeScale is the ratio of the linear dimension of an elementof an object shown in the drawing to the real lineardimension of the same element of the object.Size in drawingActual size:
20Drawing Scales Designation of a scale consists of the word “SCALE” followed by the indication of its ratio, as followSCALE 1:1 for full sizeSCALE X:1 for enlargement scales (X > 1)SCALE 1:X for reduction scales (X > 1)Dimension numbers shown in the drawing are correspondto “true size” of the object and they are independent ofthe scale used in creating that drawing.
21Basic Line Types Name according to application Types of Lines AppearanceContinuous thick line (HB)Visible line-finishingContinuous thin line (H)Dimension lineExtension lineLeader lineHatching line1.53Dash thick line (HB)Hidden line1.563Chain thin line (H)Center lineNOTE : Dimensions in mmWe will learn other types of line in later chapters.
22Basic Line Types-cont Name according to application Types of Lines AppearanceArrows Heads (HB)Arrows2 - Units5 - UnitsCutting line (HB)Section line61.53NOTE : Dimensions in mmWe will learn other types of line in later chapters.
23Meaning of LinesVisible lines represent features that can be seen in thecurrent viewHidden 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
24Example : Line conventions in engineering drawing
25End of Lecture 1Overview of an Engineering Drawing