Engineering Drawing Step by step

1. MEHRAN UNIVERSITY
OF ENGINEERING & TECHNOLOGY, JAMSHORO
B.E MECHANICAL ENGINEERING
BATCH-F16, 1ST
YEAR,1ST
SEMESTER
ENGINEERING DRAWING
&
GRAPHICS

2. MEHRAN UNIVERSITY
OF ENGINEERING & TECHNOLOGY, JAMSHORO
B.E MECHANICAL ENGINEERING
BATCH-F16, 1ST
YEAR,1ST
SEMESTER
Given
Finish
No
Internal features
make a view
difficult to read
or dimension?
Orthographic
projection
principle
Yes
Section
technique
Orthographic
projection
principle

3. MEHRAN UNIVERSITY
OF ENGINEERING & TECHNOLOGY, JAMSHORO
B.E MECHANICAL ENGINEERING
BATCH-F16, 1ST
YEAR,1ST
SEMESTER
Purpose
s
Clarify an internal feature.
Facilitate dimensioning.
Example
Regular
view
Section
view

4. MEHRAN UNIVERSITY
OF ENGINEERING & TECHNOLOGY, JAMSHORO
B.E MECHANICAL ENGINEERING
BATCH-F16, 1ST
YEAR,1ST
SEMESTER
Cutting plane
Cutting plane is an imaginary plane that cuts through the object.
Location and direction of a cutting plane depend on a hidden feature that is
needed to be revealed.
A section view is obtained by viewing the object after removed the cover up
part in the direction normal to the cutting plane.
Cutting
plane
Example
Section view

5. MEHRAN UNIVERSITY
OF ENGINEERING & TECHNOLOGY, JAMSHORO
B.E MECHANICAL ENGINEERING
BATCH-F16, 1ST
YEAR,1ST
SEMESTER
Cutting plane line
In an orthographic view, a cutting plane is presented as a “cutting plane line, CPL” and
is drawn in either of an adjacent view of the section view.
Given Direction 1 Direction 2 Direction 3
Section
view
CPL
CPL
Section
view
Section
view

6. MEHRAN UNIVERSITY
OF ENGINEERING & TECHNOLOGY, JAMSHORO
B.E MECHANICAL ENGINEERING
BATCH-F16, 1ST
YEAR,1ST
SEMESTER
Viewing
direction
Cutting plane line : Line styles
The cutting plane line is presented by a chain line here.
Begin and end the line with a short visible line.
When the line changes its direction, draw a short visible line at that corner.
Draw an arrow at about the mid-length of a short visible line, the arrow
head is pointed toward to this line in a viewing direction.
Examples
1
2
3

7. MEHRAN UNIVERSITY
OF ENGINEERING & TECHNOLOGY, JAMSHORO
B.E MECHANICAL ENGINEERING
BATCH-F16, 1ST
YEAR,1ST
SEMESTER
Do you find something wrong in the following cutting plane lines?
3
1
Yes
No Wrong!
(The arrow on the right side
should be pointed downward)
Yes
No Wrong!
(The arrow head have to
touch the short visible line)
Yes
No Wrong!
(Because the cutting plane line used
is not a chain line )
2

8. MEHRAN UNIVERSITY
OF ENGINEERING & TECHNOLOGY, JAMSHORO
B.E MECHANICAL ENGINEERING
BATCH-F16, 1ST
YEAR,1ST
SEMESTER
Change the following incorrect cutting plane line style to that previously
suggested.
11 22

9. MEHRAN UNIVERSITY
OF ENGINEERING & TECHNOLOGY, JAMSHORO
B.E MECHANICAL ENGINEERING
BATCH-F16, 1ST
YEAR,1ST
SEMESTER
Section lining : Purpose
Section lines or cross-hatch lines are added to a section view to
indicate surface that are cut by a cutting plane.
Examples
Section view
without section lines Section view
with section lines
Visible surfaces and edges behind the cutting plane are drawn in a section view.

10. MEHRAN UNIVERSITY
OF ENGINEERING & TECHNOLOGY, JAMSHORO
B.E MECHANICAL ENGINEERING
BATCH-F16, 1ST
YEAR,1ST
SEMESTER
The section lines are different for each type of material.
Cast iron,
Malleable iron Steel
Concrete
Sand Wood
Practically, the cast iron symbol is used most often for any
materials.
Section lining : Symbol
Examples

11. MEHRAN UNIVERSITY
OF ENGINEERING & TECHNOLOGY, JAMSHORO
B.E MECHANICAL ENGINEERING
BATCH-F16, 1ST
YEAR,1ST
SEMESTER
The spacing between lines may vary from 1.5 mm for small
sectioned areas to 3 mm for large sectioned areas.
Poor practices
Section lining :
Too dense Too coarse
Uneven spacing Uneven orientation
Examples

12. MEHRAN UNIVERSITY
OF ENGINEERING & TECHNOLOGY, JAMSHORO
B.E MECHANICAL ENGINEERING
BATCH-F16, 1ST
YEAR,1ST
SEMESTER
It should not run parallel or
perpendicular to contour of the view.
Section lining :
Poor practices
Examples

13. MEHRAN UNIVERSITY
OF ENGINEERING & TECHNOLOGY, JAMSHORO
B.E MECHANICAL ENGINEERING
BATCH-F16, 1ST
YEAR,1ST
SEMESTER
Class activity
Which one is a good practice in section lining?
11 22

14. MEHRAN UNIVERSITY
OF ENGINEERING & TECHNOLOGY, JAMSHORO
B.E MECHANICAL ENGINEERING
BATCH-F16, 1ST
YEAR,1ST
SEMESTER
Kind of sections
1. Full section
2. Offset section
3. Half section
4. Broken-out section
5. Revolved section (aligned section)
6. Removed section (detailed section)

15. MEHRAN UNIVERSITY
OF ENGINEERING & TECHNOLOGY, JAMSHORO
B.E MECHANICAL ENGINEERING
BATCH-F16, 1ST
YEAR,1ST
SEMESTER
Conventional practice:
Hidden lines are usually omitted within the section lined area.
Example
Hidden lines
are omitted.
Hidden lines
present.

16. MEHRAN UNIVERSITY
OF ENGINEERING & TECHNOLOGY, JAMSHORO
B.E MECHANICAL ENGINEERING
BATCH-F16, 1ST
YEAR,1ST
SEMESTER
Full section : Concept & example
A section view is made by passing the straight
cutting plane completely through the part.
Example

17. MEHRAN UNIVERSITY
OF ENGINEERING & TECHNOLOGY, JAMSHORO
B.E MECHANICAL ENGINEERING
BATCH-F16, 1ST
YEAR,1ST
SEMESTER
A closer look

18. MEHRAN UNIVERSITY
OF ENGINEERING & TECHNOLOGY, JAMSHORO
B.E MECHANICAL ENGINEERING
BATCH-F16, 1ST
YEAR,1ST
SEMESTER
Offset section : Concept & example
A section view is made by passing the bended cutting plane completely through the
part.Example
Edge views of
the cutting plane
are omitted

19. MEHRAN UNIVERSITY
OF ENGINEERING & TECHNOLOGY, JAMSHORO
B.E MECHANICAL ENGINEERING
BATCH-F16, 1ST
YEAR,1ST
SEMESTER
Half section : Concept & example
A section view is made by passing the cutting plane
halfway through an object and remove a quarter of it.
Example

20. MEHRAN UNIVERSITY
OF ENGINEERING & TECHNOLOGY, JAMSHORO
B.E MECHANICAL ENGINEERING
BATCH-F16, 1ST
YEAR,1ST
SEMESTER
Half section :
A center line is used for separating the sectioned half from the
unsectioned half of the view.
Hidden line is omitted in unsectioned half of the view.

21. MEHRAN UNIVERSITY
OF ENGINEERING & TECHNOLOGY, JAMSHORO
B.E MECHANICAL ENGINEERING
BATCH-F16, 1ST
YEAR,1ST
SEMESTER
A section view is made by passing
the cutting plane normal to the
viewing direction and removing the
portion of an object in front of it.
Broken-out section :
Example
The sectioned and unsectioned
portions are separated by
a break line.
Cutting plane line is not
necessary.
Break line is freehand drawn
as a thin continuous line.
Conventional practices

22. MEHRAN UNIVERSITY
OF ENGINEERING & TECHNOLOGY, JAMSHORO
B.E MECHANICAL ENGINEERING
BATCH-F16, 1ST
YEAR,1ST
SEMESTER
Revolved section:
A section view is made by revolving the cross-section view 90o
about a cutting plane line and drawn on the orthographic view.
Example
a
a
b
b

23. MEHRAN UNIVERSITY
OF ENGINEERING & TECHNOLOGY, JAMSHORO
B.E MECHANICAL ENGINEERING
BATCH-F16, 1ST
YEAR,1ST
SEMESTER
1. Superimposed to orthographic view.
SuperimposedBreak
2. Break from orthographic view.
Revolved section :
Placement of a cross-section view

24. MEHRAN UNIVERSITY
OF ENGINEERING & TECHNOLOGY, JAMSHORO
B.E MECHANICAL ENGINEERING
BATCH-F16, 1ST
YEAR,1ST
SEMESTER
Revolved section :

25. MEHRAN UNIVERSITY
OF ENGINEERING & TECHNOLOGY, JAMSHORO
B.E MECHANICAL ENGINEERING
BATCH-F16, 1ST
YEAR,1ST
SEMESTER6. Removed section
Removed section is created with the same concept as a
revolved section. But, the cross-section view
is shown outside the view.
Removed section : Concept

26. MEHRAN UNIVERSITY
OF ENGINEERING & TECHNOLOGY, JAMSHORO
B.E MECHANICAL ENGINEERING
BATCH-F16, 1ST
YEAR,1ST
SEMESTER
Example : Revolved vs. removed
sections.
Revolved section
Removed section
Removed section :
Comparison with a revolved section

27. MEHRAN UNIVERSITY
OF ENGINEERING & TECHNOLOGY, JAMSHORO
B.E MECHANICAL ENGINEERING
BATCH-F16, 1ST
YEAR,1ST
SEMESTER
Summary
An engineer has several choices of section techniques to reveal an internal
feature of an object.
Object having a symmetry, an appropriate choice is such as full section or
half section.
Object having several features that do not locate in-line among each other,
an offset section may be a good choice.
Broken-out section is usually used when an engineer need to reveal a local
detail of each feature.
Revolved and removed section views are efficient when an engineer need
to reveal only a cross section shape of an object.

28. MEHRAN UNIVERSITY
OF ENGINEERING & TECHNOLOGY, JAMSHORO
B.E MECHANICAL ENGINEERING
BATCH-F16, 1ST
YEAR,1ST
SEMESTER

29. MEHRAN UNIVERSITY
OF ENGINEERING & TECHNOLOGY, JAMSHORO
B.E MECHANICAL ENGINEERING
BATCH-F16, 1ST
YEAR,1ST
SEMESTER
BEARING:
Rotating shafts, which transmit motion and power, need to be supported
on bearings.
A bearing is a machine element which support another moving machine
element (shaft).
It permits a relative motion between the contact surfaces of the members,
while carrying the load.
Oil is used minimize the frictional resistance and wear.
The portion of the shaft supported by the bearing is called journal.
Types
(a) Rolling contact bearings, and
(b) Sliding contact bearings.

30. MEHRAN UNIVERSITY
OF ENGINEERING & TECHNOLOGY, JAMSHORO
B.E MECHANICAL ENGINEERING
BATCH-F16, 1ST
YEAR,1ST
SEMESTER
ROLLING CONTACT BEARINGS:
BALL, PIN, CYLINDER ARE USED.

31. MEHRAN UNIVERSITY
OF ENGINEERING & TECHNOLOGY, JAMSHORO
B.E MECHANICAL ENGINEERING
BATCH-F16, 1ST
YEAR,1ST
SEMESTER
SLIDING CONTACT BEARINGS:
1- BUSHED BEARING:
Journal or plain bearings consist of a
shaft or journal which rotates freely
in a supporting metal sleeve or shell.
There are no rolling elements in
these bearings.
A bushed bearing, is a solid bearing in
which a bush of brass or gun metal is
provided.
The outside of the bush is a driving fit
in the hole of the casting whereas the
inside is a running fit for the shaft.

32. MEHRAN UNIVERSITY
OF ENGINEERING & TECHNOLOGY, JAMSHORO
B.E MECHANICAL ENGINEERING
BATCH-F16, 1ST
YEAR,1ST
SEMESTER
SLIDING CONTACT BEARINGS:
1- BUSHED BEARING:
When the bush gets worn out,
it can be easily replaced.
In small bearings, the frictional
force itself holds the bush in
position, but for shafts
transmitting high power, grub
screws are used for the
prevention of rotation and
sliding of the bush.

33. MEHRAN UNIVERSITY
OF ENGINEERING & TECHNOLOGY, JAMSHORO
B.E MECHANICAL ENGINEERING
BATCH-F16, 1ST
YEAR,1ST
SEMESTER
SLIDING CONTACT BEARINGS:
When the bush
gets worn out, it
can be easily
replaced.
Bush material is
brass, gun metal,
steel etc.

34. MEHRAN UNIVERSITY
OF ENGINEERING & TECHNOLOGY, JAMSHORO
B.E MECHANICAL ENGINEERING
BATCH-F16, 1ST
YEAR,1ST
SEMESTER
Question#1. The isometric view of a Bushed Bearing is shown below. Draw
the following views to scale 1:1.
a. Sectional front view.
b. Side view as viewed from left.
c. Top view.
TO SUBMIT

35. MEHRAN UNIVERSITY
OF ENGINEERING & TECHNOLOGY, JAMSHORO
B.E MECHANICAL ENGINEERING
BATCH-F16, 1ST
YEAR,1ST
SEMESTER
The isometric view of a Bushed Bearing is shown below. Draw the
following views to scale 1:1.
(a). Sectional front view.
(b)Side view as viewed from left.
(c). Top view.
SOLUTION # 1.
TO SUBMIT

36. MEHRAN UNIVERSITY
OF ENGINEERING & TECHNOLOGY, JAMSHORO
B.E MECHANICAL ENGINEERING
BATCH-F16, 1ST
YEAR,1ST
SEMESTER
QUESTION # 2.The isometric view of a Bushed Bearing is shown below.
Draw the following views to scale 1:1.
a. Sectional front view.
b. Top view.

37. MEHRAN UNIVERSITY
OF ENGINEERING & TECHNOLOGY, JAMSHORO
B.E MECHANICAL ENGINEERING
BATCH-F16, 1ST
YEAR,1ST
SEMESTER
Bushed Bearing:
SOLUTION # 2.

38. MEHRAN UNIVERSITY
OF ENGINEERING & TECHNOLOGY, JAMSHORO
B.E MECHANICAL ENGINEERING
BATCH-F16, 1ST
YEAR,1ST
SEMESTER
SLIDING CONTACT BEARINGS:
2- OPENED BEARING:
This bearing consists of a 'U' shaped cast iron body with the similar shaped
collared brass, bronze or gun metal bush.
This bearing is useful for shafts rotating at slow speeds.

39. MEHRAN UNIVERSITY
OF ENGINEERING & TECHNOLOGY, JAMSHORO
B.E MECHANICAL ENGINEERING
BATCH-F16, 1ST
YEAR,1ST
SEMESTER
SLIDING CONTACT BEARINGS:
2- OPENED BEARING:
The figure shows the details of
an 'Open bearing'.
Draw the following views to
scale 1:1.
a. Front view,
b. Top view.
c. Side view as viewed from left.
TO SUBMIT

40. MEHRAN UNIVERSITY
OF ENGINEERING & TECHNOLOGY, JAMSHORO
B.E MECHANICAL ENGINEERING
BATCH-F16, 1ST
YEAR,1ST
SEMESTER
SYLLABUS
• Introduction & Basics: Introduction to graphic language, Essential drawing
instruments and their correct use. Line types and lettering. Basic drafting techniques
and standards. Curves used in engineering.
• Orthographic Projections:
• Orthographic multi view projection of some simple and composite solids.
• Sections: Sectioning and projection of auxiliary views.
• Surface Development: Surface development of simple solids such as cylinder, cone,
prism and pyramid, surface development of intersecting solids.
• Isometric Projections: Isometric projection / drawings of piping.
• Freehand/Sketching : Sketching and basic rules of sketching.
• Detail, assembly and Working Drawings: Preparing detail, assembly and working
drawings of various machine and engine parts such as, keys, cotters, foundation bolts,
screws, pulleys, couplings, bearings riveted joints and nut and bolts. Fundamentals of
geometric dimensioning and tolerancing.
• Computer Aided Drawing: Computer aided drafting (CAD). Auto CAD Software