removed and revolved sections engineering108.com
TRANSCRIPT
SECTIONING OF A
MACHINE COMPONENT
BY ANY ONE SECTION
PLA NE ,OUT OF THREE
FOLLOWING MENTIONED
SECTION PLANES
(1)BY A VERTICAL SECTION PLANE
(PARALLEL TO PRINCIPLE V.P.)
Hence ,
(a)The real or true shape of the section is
observed in its F.V., known as SEC. F.V.
- AB
(b)Section plane will be seen as a cutting
plane line (similar to center line ,thick at ends)
with corresponding horizontal vision direction
arrows at the center of thick ends in its T.V. &
S.V.
(2)BY A HORIZONTAL SECTION PLANE
Hence,
(a)The real or true shape of the section is observed in
its T.V., known as SEC. T.V. - AB
(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.
(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., known as SEC. L.H.S.V – AB or SEC. R.H.S.V - AB
(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.
50
50
50
10
3015
6040
30
15
R12.55
15
30
A
B
X
Figure shows isometric view of a machine component. Draw its
(1)Front view, Top view & L.H.S View, using 3rd angle method of projections.
(2)Sectional Front view, Top view & L.H.S.V., using 3rd angle method of projections.
10
50 50
604030
1525
5
30
50
15
Front View
Top View
L.H.S.View
1.
X
Ortho. Views (No sectioning)
A
B
A
B
X
Retained split of the machine parts
XIt will be nearer to V.P. in 1st angle method & against the vertical plane in 3rd angle method.
50 50
604030
1525
5
10
30
Top View
Sectional Front View -ABL.H.S. View
A B
A
B
B
A
2.(With sectioning)
120
28
2020
28
60
Ø30Ø20
14
7A
A
X
Figure shows the pictorial view of a machine component. Draw its following views as per First angle method of projections
(1) Front view from X direction.(2) Sectional top view-AA
(3) L.H.S. View
120
28
20
Sketch shows the assumed cut model (retained part of the machine component / split against the observer) due to horizontal section plane passing through AB.
X
120
60
28Ø30, 7deep Ø20
2020
14
F.V.
Sectional T.V.
L.H.S.V.
A AA A
60
2 0
90
20
40
6 0
10
30
R10
XA
BFigure shows the pictorial
view of a machine components. Draw its following views, using 3rd angle method of projections.
(1) Front view from arrow X(2) Top View (3) Sectional R.H.S.V - AB
B
A
Retained split of the machine parts
Retained split, will be nearer to V.P. in 1st angle method & against the vertical plane in 3rd angle method.
No hatching in this area as not contained in the section plane
8 0
2 0
20
20
60 9 0
4 0
30
A
A
AF.V.
T.V.
SEC.R.H.S.V
HALF SECTION
SPECIALSECIONS
A
C
B
HALF SECTIONAL F.V.-AB HALF SECTIONALLEFT S.V.-BC
TOP VIEW
In half section the hidden line should be used only on unsectioned side of the view, provided that they are necessary for dimensioning or for clarity.
REMOVED & REVOLVED SECTIONS
SPECIAL SECTIONS
REMOVEDSECTION
REVOLVEDSECTION
REMOVEDSECTION
REVOLVED SECTION
REMOVED SECTION
REMOVED SECTIONS
NOTE:- (As per Previous I S 696 – 1972 Page 38)
When the cutting plane passes (contains) the
center line of such elements as,
Shafts,bolts,nuts,rods,rivets,keys,pins, pulley
arms, spokes, webs(ribs),screws,ball or roller
bearings or similar shapes - no section lining or
sectioning is needed for the objects , i.e. the
hatching should be eliminated.
(See the next demonstrating exercises
following the above rule)
Vertical Collared Shaft (supported on webbed and drilled flange) in Conventional section in F.V., along withthe T.V.
Note:- As a rule, all the hidden lines should be omitted from a sectional view. The only exemption is where the hidden lines are absolutely Indispensable for clarification or for dimensioning.
Actual or true projections are not preferred to draw
Section lines are to be staggered as
shown at R
OFFSET SECTION: The path of the cutting plane is bent to pass through features not located in a straight line, i.e. it is offset to pass through both principle features of the object. Example is shown below in Ex. 1 & Ex. 2.
B
BEx. 1.
R
AA
P Q
F.V (SECTION –AA)
Section lines are to be staggered as shown at P,Q
Ex. 2.
Off set sectioning
pulley
Tap bolt(fastener)
shaft
Shaft and pulley partly broken out to show internal fastening
This is used to show only a desired features of the object . No cutting plane lines are necessary , shown by wavy line
Partial (broken, local or Zonal)
Section.
See Ex. A,B & C
Ex. A
Partial (broken, local or Zonal)
Section.
Ex. B
SPECIAL SECTION SECTION IN TWO INTERSECTING PLANES
A
B
SEC. F.V. - ABR.H.S.V.
SPECIAL SECTION
Cross hatching of adjacent parts See at (1) & (2)
(1)
Hatching more than two adjacent components at (2)
(2)
A
B
C
(hatchedat 60 )
D45
45
hatchedat 30on D
SPECIAL SECTION
A B
F.V.
SEC.T.V.Two vertical plates ,fastened by a horizontalrivet is shown in its F.V. & T.V., cut by horizontalsection plane. Note the rivet is shown in section inT.V.
CONVENTIONAL REPRESENTATIONOF CYLINDER IN WHICH CIRCULAR OR RECTANGULAR HOLE CUT IN ITS F.V.Note:- The actual shape of hole or slot may be understood fromits side view.
For circular hole
For rectangular slot
ACTUALPROJECTIONS
AUXILARY SECTION
A
SECTION AA
A
It is the sectional view not in principal planes. it may be full, half ,broken out , removed or revolved.The section should be shown in its normal auxilary position and clearly identified with a cutting plane with letters
AUXILIARY SECTION (as specialsection)
A
A
BC D
DCB
SECTION
AASECTION
BB SECTION
CC
SECTION
DD
SUCCESSIVE SECTIONS (REMOVED TYPE)
A
A
BC D
DCB
SUCCESSIVE SECTIONS (REMOVED TYPE)
SECTION
AA SECTION
BB
SECTION
CC
SECTION
DD
SUCCESSIVE SECTIONS (REMOVED TYPE)
Top View
Sectional Front View -ABL.H.S. View
A B
A
B
B
A
2.(With sectioning)
Ø30,2 HOLES
7
26
7
15
13
70
15
15
30
Ø30
R20
26
45
Ø30,2 HOLES
13
12
26
15 70
15 1510
26
13
30
R20
ø30
7
65
81
SCECTIONAL F.V.-AA
TOP VIEW
L.H.S.V.
70
10
0
Aim:-Sketch-1, shows Isometric View of a machine part. Draw its following orthographic views using third angle method of projections, giving dimensions.
(1) Sectional F.V.-AA
(2) T.V.
(3) L.H.S.V
A
A
14
8
65
Φ20R35
Φ36
70100
A
ALEFT HAND SIDE VIEW SECTIONAL FRONT VIEW AA
TOP VIEW
X
SCALE:- 1:1SYMBOL OF PROJECTION METHOD, NOT SHOWN
Sketch-1
14
30
14
70
34
2 HOLES,Φ 14
Φ36
Φ20
R35 8
100
14
65
14 `
100
App
rox.
25
AA
SOLUTION`
14
1414
8
30
70 14
1414
8
100
A
ALEFT HAND SIDE VIEW SECTIONAL FRONT VIEW AA
TOP VIEW
SCALE:- 1:1SYMBOL OF PROJECTION METHOD, NOT SHOWN
SOLUTION`
App
rox.
25
AA
100
14
8
65
Φ20R35
Φ36
2 HOLES,Φ 14
X
34
Φ36
Φ20
R35
A
A
Aim:-Sketch-1, shows Isometric View of a machine part. Draw its following orthographic views using third angle method of projections, giving dimensions.
(1) Sectional F.V.-AA
(2) T.V.
(3) L.H.S.V
14
30
Hatch (section) lines, to be kept at 1 to 1.5 mm apart, at 45° normally, but depends on areas to be hatched.
14
1448 70
50
10
30
40,DEPTH 24
60
Ø64
30
140
24
Ø40
50
10
L.H.S.VFRONT VIEW
14
14
48
70
TOP VIEW