Lecture 1 Introduction to Engg Drawing.pptx

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1. Engineering Drawing & Graphics Lecture 01 Introduction to Engineering Drawing and Graphics Instructor: Engr. Ismail Khan Lecturer Mechanical Engineering Department UET Peshawar 1

2. Marks Distribution Mid Term Exam (Drawing Paper): 20 % Sessional Mark (Quizzes, Assignments): 20 % Final Term Exam (Paper and Viva voce): 60 % 2

3. Recommended Books Text Books: Elementary Engineering Drawing, Revised and Enlarged Edition by N. D. Bhatt. Introduction to AutoCAD 2009 2D and 3D Design First edition Alf Yarwood Reference Book: First year engineering drawing by A.C. Parkinson 3

4. Course Learning Outcomes Understand the basic technique and tools of engineering drawing and graphics as a language of communication. Draw 2-D and 3D Drawings/Sketches using AutoCAD drawing and editing tools. Draw projects related to Electrical Engineering applications by use of DESIGN CENTER tool in AutoCAD. 4

5. LECTURE CONTENTS Drawing Standards Graphics Language Engineering Drawing Drawing Function Drawing Scales Traditional Drawing Tools 5

6. Overview of an Engineering Drawing 6

7. 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 Language The word languages are inadequate for describing the size , shape and features completely as well as concisely. You can easily understand that … 7

8. Effectiveness of Graphic Language 8

9. Effectiveness of Graphic Language This Side up Handle With Care Fragile Keep Dry 9

10. Graphic language in “engineering application” use l ines to represent the surfaces , edges and contours of objects. A drawing can be done using freehand , instruments or computer methods. Composition of Graphic Language The language is known as “ drawing ” or “ drafting ” . 10

11. Freehand drawing The lines are sketched without using instruments other than pencils and erasers. Example 11

12. Instrument drawing Instruments are used to draw straight lines, circles, and curves concisely and accurately. Thus, the drawings are usually made to scale. Example 12

13. Computer drawing The drawings are usually made by commercial software such as AutoCAD, solid works , PRO – E, etc. Examples 13

14. Example of CAD 14

15. Example of CAD 15

16. Example of CAD 16

17. This wiring diagram is also included as an engineering drawing !!! Examples of Engineering Drawing 17

18. Engineering Drawing

19. Elements of Drawing 19

20. Knowledge and Skill Required 20

21. Engineering Drawing Definition A language —a graphical language that communicates ideas and information from one mind to another. 21

22. Types of Measuring Systems English Feet and Inches Metric Meters and Millimeters 22

23. Engineering Drawing Function Drawings convey the following critical information: Geometry – the shape of the object; represented as views; how the object will look when it is viewed from various angles, such as front, top, side, and so on. Dimensions – the size of the object is captured in accepted units. Tolerances – the allowable variations from the nominal size for each dimension. Material – represents what the item is made of. Finish – specifies the surface quality of the item, functional or cosmetic. 23

24. Line Types and Styles Visible lines Represents visible edges and boundaries Continuous and thick (0.5 - 0.6 mm) Hidden lines Represents hidden edges and boundaries Short-dashed lines and medium thick (0.35 – 0.45 mm) Center lines Represents axes of symmetry Long and short-dashed and thin (0.3 mm) Break lines Used to show imaginary breaks in objects, made up of series of connecting arcs Continuous line and thick (0.5 – 0.6 mm) 24

25. Line Types and Styles Dimension and Extension lines Used to show the size of an object. Placed between two extension lines and its terminated by arrowheads, which indicates the directions and extent of the dimension Continuous lines and thin (0.3 mm) Cutting Plane Lines Used to show where an imaginary cut has been made through the object in order to view interior features The line type is phantom and very thick (0.6 – 0.8 mm) Arrows are placed at both ends of the cutting plane line to indicate the direction of sight Section lines Used to show areas that have been cut by the cutting plane Grouped in parallel line pattern and usually drawn at a 45 angle Continuous line and thin (0.3 mm) 25

26. Line Types and Styles Visible Line Hidden Line Center Line Break Line Dimension and Extension Line Cutting Plane Line Section Line 26

27. Line Types and Styles 27

28. Line Types and Styles 28

29. Line Types and Styles 29

30. Drawing Standard

31. Introduction Standards are set of rules that govern how technical drawings are represented. Drawing standards are used so that drawings convey the same meaning to everyone who reads them. 31

32. Paper Size / Drawing Sheet 32

33. ISO I nternational S tandards O rganization Standard Code ANSI A merican N ational S tandard I nstitute USA JIS J apanese I ndustrial S tandard Japan BS B ritish S tandard UK AS A ustralian S tandard Australia D eutsches I nstitut f ü r N ormung DIN Germany Country Code Full name 33

34. Drawing space Drawing space Title block d d c c c Border lines 1. Type X (A0~A4) 2. Type Y (A4 only) Orientation of Drawing Sheet Title block Sheet size c (mm) d (mm) A4 10 25 A3 10 25 A2 10 25 A1 20 25 A0 20 25 34

35. Drawing Sheet Trimmed paper of a size A0 ~ A4. Standard sheet size ( JIS ) A4 210 x 297 A3 297 x 420 A2 420 x 594 A1 594 x 841 A0 841 x 1189 A4 A3 A2 A1 A0 (Dimensions in millimeters) 35

36. Drawing Sheet Layout Layout of drawing sheet shows the title block and border lines as given below. 36

37. DRAWING LAYOUT All engineering drawings should feature a TITLE BLOCK . TITLE:- TITLE OF THE DRAWING NAME:- NAME OF THE PERSON WHO PRODUCED THE DRAWING CHECKED:- BEFORE MANUFACTURE, DRAWINGS ARE USUALLY CHECKED VERSION:- MANY DRAWINGS ARE AMENDED, EACH REVISION MUST BE NOTED DATE:- THE DATE THE DRAWING WAS PRODUCED OR LAST AMENDED NOTES:- ANY NOTE RELEVANT TO THE DRAWING SCALE:- THE SCALE OF THE DRAWING COMPANY NAME:- NAME OF THE COMPANY PROJECTION:- THE PROJECTION SYSTEM USED TO CREATE THE DRAWING 37

38. SAMPLE OF DRAWING SHEET 38

39. Drawing Scales

40. Drawing Scales Scale is the ratio of the linear dimension of an element of an object shown in the drawing to the real linear dimension of the same element of the object. Size in drawing Actual size Length, size : 40

41. Recommended Drawing Scales 41

42. Drawing Scales Designation of a scale consists of the word “ SCALE ” followed by the indication of its ratio , as follow SCALE 1:1 for full size SCALE X :1 for enlargement scales (X > 1) SCALE 1: X for reduction scales (X > 1) Dimension numbers shown in the drawing are correspond to “ true size ” of the object and they are independent of the scale used in creating that drawing. 42

43. Traditional Drawing Tools

44. Drawing Instruments Drawing board/table. Drawing sheet/paper. Drafting tape. Pencils. Eraser. Sharpener. T-square. Set-squares/triangles. Scales. Compass and divider. 44

45. Drawing board 45

46. Drawing table 46

47. Drawing sheet/paper 216 X 280 mm 280 X 382 mm 382 X 560 mm 585 X 726 mm 47

48. Drafting tape 48

49. T-square 49

50. Eraser 50

51. Sharpener 51

52. Scales 52

53. Compass and Divider 53

54. Pencil and Drawing Board 2H or HB for thick line 4H for thin line 54

55. Set-squares/triangles 55

56. 56

57. 57

58. 58

59. 59

60. Thank You 60