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.

R A B X Figure shows isometric view of a machine component. Draw its (1)Front view, Top view & L.H.S View, using 3 rd angle method of projections. (2)Sectional Front view, Top view & L.H.S.V., using 3 rd angle method of projections.

Front View Top View L.H.S.View 1. X Ortho. Views (No sectioning)

A B Retained split of the machine parts X It will be nearer to V.P. in 1 st angle method & against the vertical plane in 3 rd angle method.

Top View Sectional Front View -AB L.H.S. View A B A B B A 2. (With sectioning)

Ø30 Ø A 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

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

Ø30, 7 deep Ø F.V. Sectional T.V. L.H.S.V. A A AA

 30 R10 X A B Figure shows the pictorial view of a machine components. Draw its following views, using 3 rd 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 1 st angle method & against the vertical plane in 3 rd angle method. No hatching in this area as not contained in the section plane

 30 A A A F.V. T.V. SEC. R.H.S.V

HALF SECTION SPECIAL SECIONS

A C B HALF SECTIONAL F.V.-AB HALF SECTIONAL LEFT 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 REVOLVED SECTION REMOVED SECTION

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 with the 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 B Ex. 1. R

A A PQ 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 SEC. F.V. - AB R.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 (hatched at 60  ) D 45  hatched at 30  on D SPECIAL SECTION

AB F.V. SEC.T.V. Two vertical plates,fastened by a horizontal rivet is shown in its F.V. & T.V., cut by horizontal section plane. Note the rivet is shown in section in T.V.

CONVENTIONAL REPRESENTATION OF CYLINDER IN WHICH CIRCULAR OR RECTANGULAR HOLE CUT IN ITS F.V. Note:- The actual shape of hole or slot may be understood from its side view. For circular hole For rectangular slot ACTUAL PROJECTIONS

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 special section)

A A B C D D C B SECTION AA SECTION BB SECTION CC SECTION DD SUCCESSIVE SECTIONS (REMOVED TYPE)

A A B C D D C B

SECTION AA SECTION BB SECTION CC SECTION DD SUCCESSIVE SECTIONS (REMOVED TYPE)

Top View Sectional Front View -AB L.H.S. View A B A B B A 2. (With sectioning)

Ø30,2 HOLES Ø30 R

R20 ø SCECTIONAL F.V.-AA TOP VIEW L.H.S.V

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 Φ20 R35 Φ AA LEFT HAND SIDE VIEW SECTIONAL FRONT VIEW AA TOP VIEW X SCALE:- 1:1 SYMBOL OF PROJECTION METHOD, NOT SHOWN Sketch HOLES,Φ 14 2 HOLES,Φ 14 Φ36 Φ20R ` 100 Approx.25 A ASOLUTION`

AA LEFT HAND SIDE VIEW SECTIONAL FRONT VIEW AA TOP VIEW SCALE:- 1:1 SYMBOL OF PROJECTION METHOD, NOT SHOWN SOLUTION`Approx.25 A A Φ20 R35 Φ36 2 HOLES,Φ 14 2 HOLES,Φ 14 X 34 Φ36 Φ20R35A 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 1430 Hatch (section) lines, to be kept at 1 to 1.5 mm apart, at 45° normally, but depends on areas to be hatched.

 40,DEPTH 24  60

Ø Ø L.H.S.V FRONT VIEW TOP VIEW