orthographic projections of engg. graphics

orthographic projections of engg. graphics

1. TOPICS OF “ENGINEERING GRAPHICS ”
(Mechanical Portion)
( C )ORTHOGRAPHIC PROJECTIONS
FROM GIVEN ISOMETRIC VIEW
( D )ISOMETRIC VIEW/PROJECTIONS
FROM GIVEN ORTHOGRPHIC VIEWS
WithoutSections With Sections
View i.e. drawing Projections
Topic no. Topic Content No. of Lectures
07
05

2. TYPES OF LINES
USED IN
ENGINEERING
DRAWING
APPLICATIONS OF
LINES ON
DRAWING
G
2
CUTTING PLANE
LINE (IN T.V)
CONTINUOUS
THICK
A
A
G
1
CUTTING PLANE
LINE (IN F.V)G
1
B
CONTINUOUS
THIN (WAVY)
B
C SHORT ZIGZAG
THIN
C
D
D
D
CONTINUOUS
THIN
D
E
SHORT DASH
MEDIUM (DOTED
LINE )
E
F
LONG CHAIN
THIN (CENTER
LINE)
F
40
30
25
150
60

3. Trimmedanduntrimmeddrawingsheet
sizesarecommerciallydesignatedasA
0
(Maximumsize),A
1,A
2,A
3,A
4&A
5(Least
size).
InEngineeringGraphics’termwork,all
the4sheetswillbeofA
2(approximately½
Imperial)size
Thefollowingtwosystemsareadoptedfor
dimensioningpurposesonorthographic
viewsaswellasonpictorialview.
Dimensioning Techniques

4. 20
35
ALIGNED
SYSTEM
(FOR A
2TO A
5
SHEET SIZE)
UNIDIRECTIONAL
SYSTEM
(FOR LARGE SIZED
SHEETS)
35
20
ARROW HEADS
(H x 3H)
3H
H

5. ORTHOGRAPHIC PREOJECTIONS
(MULTI VIEW REPRESENTATIONS i.e. F.V.,
T.V. & S.V. –L.H.S.V OR R.H.S.V) FROM
ISOMETRIC VIEW
PLANES OF PROJECTIONS
QUADRANTS
VISION DIRECTIONS

6. SCALINGOFADRAWING(FullSize1:1,
Reduced1:2orEnlarged5:1)
VIEWES
METHODS OFPROJECTIONS WITH
THEIRSYMBOLS

7. (AS PER BUREAU OF INDIAN STANDARDS
FOR ENGINEERING DRAWING.)
SCALING OF A DRAWING
RECOMMENDED SCALES
1.FULL SCALE e.g. 1: 1
Incertaincasestheengineeringcomponentsmay
beverylargeorverysmallfordrawingpurposes,
hencethecorrespondingscalemaybepreferred
fromthefollowing

8. 3.ENLARGED SCALE e.g. 50:1, 20:1, 10:1,
5:1, 2:1
2.REDUCED SCALE e.g. 1:2, 1:2.5, 1:5,
1:10, 1:20,
1:15, 1:100,
1:200, 1:500,
1:1000, 1:2000,
1:5000,
1:10000

9. SYMBOLS USED ON
ENGINEERING DRAWING SHEET
FIRST ANGLE METHOD
OF
ORTHOGRAPHIC
PROJECTIONS
THIRD ANGLE METHOD
OF
ORTHOGRAPHIC
PROJECTIONS
M/c.PARTSARENEVERASSUMEDINSECOND
ORINFOURTHQUADRANT, ASTHEVIEWS
MAYOVERLAPONONEANOTHER ABOVEXY
ORBELOWXYRESPECTIVELY.

10. HP
VP
PP
ISOMETRIC VIEW
OF
FIRST ANGLE METHOD OF PROJECTIONS (FOR L.H.S.V.)
Z
1
X
Y
Y
X
OBJECT IN
FIRST
QUADRANT
(FOR L.H.S.V.)

11. Fig.2(c)showsturningoftheplanesH.P&P.P
withtheirrespectivehinges,considering
V.Pasfixedplane.
b)F.ViswithinL&H,T.ViswithinL&D,
WhileL.H.S.ViswithinH&D.
Itmaybenotedthat:-
(a)F.V.(Xdirectionalview)isonV.P,T.V.(Y
directionalview)isonH.P,whileL.H.S.V(Z
1
directionalview)isonP.P
c)ThesymbolforI
st
anglemethodofprojections
isplacedasshownonfig.2(c)

12. Fig. 2(c)
X Y
H.P
T.V.
L
V.P
F.V.
L.H.S.V.
D
P.P
H

13. AIM:Fig.2(a)showsthePictorial
(ISOMETRIC)viewofacut
block.Draw itsfollowing
orthographicviewsusingI
st
angle
methodofprojections.
I.Front View
II.Top View
III.R. H. S.View

14. X
Fig 2(b)
P.P
Z
2
V.P
H.P
Z
2
Fig 2(a)
X
Y
YY

15. Note:I
st
anglemeans,theblockisassumedin
frontofV.P,aboveH.PandinsideP.P,
asinfig.2(b)wheretheF.V.is
projectedonV.P,seeninXdirection,
T.V.isprojectedonH.P,seeninY
direction&R.H.S.V.isprojectedon
P.P,seeninZ
2direction

16. Itmaybenotedthat:-
a)F.V.(Xdirectionalview)isonV.P,T.V.(Y
directionalview)isonH.P,whileR.H.S.V(Z
2
directionalview)isonP.P
Fig.2(c)showsturningoftheplanesH.P&P.Pwith
theirrespectivehinges,consideringplaneV.Pas
fixedplane.
b)F.ViswithinL&H,T.ViswithinL&D,While
R.H.S.ViswithinH&D.
c)ThesymbolforI
st
anglemethodofprojectionsis
placedasshownonfig.2(c)

17. Fig. 2(c)
H.P
T.V.
L
F.V.
V.P
X Y
R.H.S.V.
D
P.
P
H

18. AIM:Fig.3(a) showsthePictorial
(ISOMETRIC)viewofacutblock.
Drawitsfollowingorthographicviews
usingIII
rd
anglemethodofprojections.
I. Front View
II.Top View
III.Left Hand Side View

19. H.P
P.P
X
Y
Z
1
X
Y
V.P
Fig 3(b)
Y
Z
1
X
Fig 3(a)
Plane H.P turned
up(above V.P)
Plane P.P turned side
way(towards left side of
plane V.P)

20. Note:III
rd
anglemeans,theblockis
assumedbehindV.P,belowH.Pand
insideP.P,asinfig.3(b)wheretheF.V.
isprojectedonV.P,seeninXdirection,
T.V.isprojectedonH.P,seeninY
direction&L.H.S.V.isprojectedon
P.P,seeninZ
1direction

21. c)ThesymbolforIII
rdanglemethodofprojections
isplacedasshownonfig.3(c)
b)F.ViswithinL&H,T.ViswithinL&D,While
L.H.S.ViswithinH&D.
Fig.3(c)showsturningoftheplanesH.P&P.Pwith
theirrespectivehinges,consideringplaneV.Pas
fixedplane.
Itmaybenotedthat:-
a)F.V.(Xdirectionalview)isonV.P,T.V.(Y
directionalview)isonH.P,whileL.H.S.V(Z
1
directionalview)isonP.P

22. T.V.
4
D
6
L.H.S.V
2
F.V.
L
X Y
Fig.
3(c)

23. AIM:Fig.4(a)showsthePictorial
(ISOMETRIC)viewofacutblock.
Drawitsfollowingorthographic
viewsusingIII
rd
anglemethodof
projections.
I.Front View
II.Top View
III.Right Hand Side View

24. X
Y
X
Y
H
P.P
Z
2
Fig. 4(b)
Planes H.P, V.P & P.P are assumed as transparent
Y
Z
2
Fig. 4(a)
X
H.
P
V.P

25. Note:III
rd
anglemeans,theblockisassumed
behindV.P,belowH.PandinsideP.P,as
infig.4(b)wheretheF.V.isprojected
onV.P,seeninXdirection,T.V.is
projectedonH.P,seeninYdirection&
R.H.S.V.isprojectedonP.P,seeninZ
2
direction.

26. b)F.ViswithinL&H,T.ViswithinL&D,
WhileR.H.S.ViswithinH&D.
c)ThesymbolforIII
rdanglemethodofprojections
isplacedasshownonfig.4(c)
Fig.4(c)showsturningoftheplanesH.P&P.Pwith
theirrespectivehinges,consideringplane
V.Pasfixedplane.
Itmaybenotedthat:-
a)F.V.(Xdirectionalview)isonV.P,T.V.(Y
directionalview)isonH.P,whileR.H.S.V(Z
2
directionalview)isonP.P

27. YX
H
.
P
T.V.
D
V
.
P
F.V.
L
Fig. 4(c)
P
.
P
R.H.S.V.
H

28. Stepbystepprocedure
Suggested to prepare
Orthographicviews(Firstangle
method) forThesimple
componentShownpictoriallyin
figure

29. 20
60
R40
ISOMETRIC
VIEW
X

30. R40
20
100
80
ø40
80
20
TOP VIEW
FRONT VIEWR.H.S.V
SCALE: 1:1
SYMBOLIS
NOT MARKED
20 20

31. FIGURESHOWSISOMETRIC VIEWOFA
SIMPLEOBJECT(WITHOUT DIMENSIONS)
SHOWITSTHREEORTHOGRAPHIC VIEWS
Use First Angle
Method
1.Front View
2.Top View
3.L.H.S.View
A
B
a
b
3
c
2
1

32. F.V
T.V
L.H.S.V.
B
a
b
c
3
2
1
b
3
A

33. FIGURESHOWSISOMETRICVIEWOFAN
OBJECT(WITHOUT DIMENSIONS)SHOWITS
THREEORTHOGRAPHICVIEWS
Use Third
Angle Method
1.Front View
2.Top View
3.L.H.S.View
1.Front View
2.Top View
3.L.H.S.View
A
a
b
3
c
2
1

34. FRONT VIEWL.H.S VIEW
TOP VIEW
A
ab
3
c
2 1

35. Aim:Figureshowsisometric
view,ofasimplemachine
component.
DrawitsfollowingOrthographic
views,&dimensionthem.
1.Front View
2.Top View
3.R.H.S. View
Use First Angle Method of projection

36. Figure, is the isometric view
X
Figure
L = 75+25=100
H = 10+30=40
D=50

37. 10
10
F.V.
25
75
40
T.V.
ORTHOGRAPHIC
VIEWS
F.V
L=100
H=40
T.V
L=100
D=50
S.V
D=50
H=40

38. 30
10
25 SQ
15 SQ
Ø30,Depth 10
40 SQ
ISOMETRIC
ORTHO. VIEWS

39. 25 Sq
40
15
453535
15 Sq
40 Sq
Ø30
5
10
30
10
5
10
R.H.
S.V.
F.V.
T.V.

40. Figureshowstheisometric
viewofaverticalshaftsupport.
Drawitsallthethreeviews,
usingfirstanglemethodof
projections.
Givethenecessarydimensions
asperalignedsystem.
Exercise :-

41. ISOMETRIC
VIEW Ø40
Ø64
24
50

42. 14
14
48
70
24
10
Ø40
50
Ø64
30
140
L.H.S.VFRONT VIEW
TOP VIEW

43. Isometric view of a rod support is
given.
Draw its all the three orthographic
views, using first angle method of
projections.
Give all the dimensions.
Exercise :-

44. ISOMETRIC VIEW
16
20
R22
40
X

45. TOP VIEW
R22
2040
10
FRONT VIEW
RIGHT SIDE
VIEW
140
2080
SCALE: 1:1
3030
66
26
30

46. 10
20R20
R8
30
ISOMETRIC
ORTHO. VIEWS

47. 45
30
8
20 25
16
R8
R20
30
20
10
100

48. SECTIONING OF A
MACHINE COMPONENT
BY ANY ONE SECTION
PLA NE ,OUT OF THREE
FOLLOWING MENTIONED
SECTION PLANES

49. (1)BYAVERTICALSECTIONPLANE
(PARALLELTOPRINCIPLEV.P.)
Hence,
(a)Therealortrueshapeofthesectionis
observedinitsF.V.
(b)Sectionplanewillbeseenasacutting
planeline(similartocenterline,thickat
ends)withcorrespondinghorizontalvision
directionarrowsatthecenterofthickendsin
itsT.V.&S.V.

50. (2)BY A HORIZONTAL SECTION PLANE
Hence,
(a)The real or true shape of the section is observed in
its T.V.
(b) The cutting or section plane will be observed as a
cutting plane line (similar to center line ,thick at
ends) with the corresponding vertically downward
vision direction arrows at the center of the thick
ends in its F.V. and in S.V.

51. (3) BY A SECTION PLANE , NORMAL TO
BOTH H.P. AND V.P.(i.e. parallel to
profile plane or side view plane)
Hence,
(a)The real or true shape of the section is observed in
its S.V.
(b) The cutting or section plane will be observed as a
cutting plane line (similar to center line ,thick at
ends) with the corresponding vertically downward
vision direction arrows at the center of the thick
ends in its F.V. and in T.V.

52. 50
15
15
Figureshowsisometricviewofa
machinecomponent.Drawits
(1)Frontview,Topview&L.H.S
View,using3
rd
anglemethod
ofprojections.
(2)SectionalFrontview,Top
view&L.H.S.V.,using3
rd
anglemethodofprojections.

53. 10
50 50
604030
1525
5
30
50
15
Front View
Top View
L.H.S.View
1.
Ortho. Views (No sectioning)

54. A
B
Retained split of the
machine parts
ItwillbenearertoV.P.
in1
st
anglemethod&
againstthevertical
planein3
rd
angle
method.

55. 50 50
604030
1525
5
10
30
Top View
Sectional Front View -ABL.H.S. View
A B
A
B
2.
(With sectioning)

56. 20
20
60
A
A
X
Figureshowsthepictorial
viewofamachinecomponent.
Drawitsfollowingviewsas
perFirstanglemethodof
projections
(1)FrontviewfromXdirection.
(2)Sectionaltopview-AA
(3)L.H.S.View

57. 20
Sketchshowstheassumedcutmodel(retainedpartof
themachinecomponent/splitagainsttheobserver)due
tohorizontalsectionplanepassingthroughAB.
X

58. 120
60
28
Ø30, 7deep
Ø20
20
20
14
F.V.
Sectional T.V.
L.H.S.V.
A A
A A

59. 20
60
30
X
A
B
Figureshowsthepictorialview
ofamachinecomponents.
Drawitsfollowingviews,
using3
rd
anglemethodof
projections.
(1)FrontviewfromarrowX
(2)TopView
(3)SectionalR.H.S.V-AB

60. B
A
Retained split of the
machine parts
Retainedsplit,willbe
nearertoV.P.in1
st
anglemethod &
againstthevertical
planein3
rd
angle
method.
Nohatchingin
thisareaasnot
containedinthe
sectionplane

61. 80
20
2020
60
90
40
A
A
A
F.V.
T.V.
SEC.
R.H.S.V

62. HALF SECTION
SPECIAL
SECIONS

63. A
C
B
HALF SECTIONAL F.V.-AB
HALF SECTIONAL
LEFT S.V.-BC
TOP VIEW

64. REMOVED & REVOLVED
SECTIONS
SPECIAL SECTIONS

65. REMOVEDSECTION
REVOLVED
SECTION
REMOVED
SECTION

66. REVOLVED SECTION

67. REMOVED SECTION

68. REMOVED SECTIONS