The document provides information on working drawings, including detail drawings, assembly drawings, and dimensioning. It defines detail drawings as showing a single part with dimensions and notes, while assembly drawings show various parts assembled together. The purpose of detail drawings is to provide manufacturing instructions for a part, while assembly drawings convey the assembled shape, dimensions, and relative positioning of parts. The document outlines the typical information included in detail and assembly drawings, such as title blocks, views, dimensions, and part lists. It provides examples and best practices for creating detail and assembly drawings, including proper dimensioning, use of section lines, and leader lines.
Discusses the contents of detail drawings including title blocks, dimensions, and surface finishing.
Explains the various types of assembly drawings: exploded, general, and detailed assembly.
Key elements included in general assembly drawings such as part list, notes, and assembly operations.
Steps for creating assembly drawings highlighting view selection, detail addition, and BOM creation.
Best practices for selection of views, handling hidden lines, and using section techniques in drawings.
Examples illustrating various assembly steps and section line practices, reinforcing learned concepts.
Illustrates how to interpret assembly drawings through examples of machine components and their functions.
Discusses the significance of tolerances and surface finishing in functional assembly and operation of parts. Importance of controlling surface characteristics like roughness and waviness for accurate machining.
DEFINITION
Working drawing isa set of drawing used
during the work of making a product.
Working drawing
Detail
drawing
Assembly
drawing
5.
DEFINITION
Detail drawing isa multiview representation
of a single part with dimensions and notes.
Assembly drawing is a drawing of various
parts of a machine or structure assembled in
their relative working positions.
6.
Detail drawing conveysthe information
and instructions for manufacturing the part.
4. functional relationship among various
components.
1. completed shape of the product.
2. overall dimensions.
PURPOSE
Assembly drawing conveys
3. relative position of each part.
INFORMATION IN
DETAIL DRAWING
2.1Shape description
2.2 Size description
2.3 Specifications
1. General information
2. Part’ s information
Title block
Object’s
views
Notes
9.
GENERAL INFORMATION
Nameof company
Title of drawing (usually part’s name)
Drawing sheet number
Name of drafter, checker
Relevant dates of action
(drawn, checked, approved etc.)
Revision table
Unit
Scale
Method of projection
10.
PART’ S INFORMATION
Orthographic drawing
Pictorial drawing
Dimensions and Tolerances
Specifications
General notes
Type of material used
Surface finish
General tolerances
Part number, name,
number required
Shape
Size
Heat treatment
11.
If not thecase,
- apply enough spacing between parts.
-draw all parts using the same scale.
-Otherwise, the scale should be clearly note
under each part’s drawing.
Draw one part to one sheet of paper.
RECOMMENDED PRACTICE
Standard parts such as bolt, nut, pin, bearing
do not require detail drawings.
12.
Part No., Partname, material, Number required
Notes
Unit, fillets & rounds sizes etc.
Completed dimension
orthographic drawing
Title block
PLACING AN INFORMATION
(This course)
13.
EXAMPLE : Interpretingdetail drawing
General note
Revision table
Title block
1. Orthographic
views
2. Dimensions
& Tolerances
3. Surface
finishing
ProjectionGen. tolerance
1. Exploded assemblydrawings
3. Detail assembly drawings
TYPES OF ASSEMBLY DRAWING
2. General assembly drawings.
The parts are separately display, but they are aligned
according to their assembly positions and sequences.
All parts are drawn in their working position.
All parts are drawn in their working position with a
completed dimensions.
Only dimensions relateto
machine’s operation are
given.
Only dimensions relate to
machine’s operation are given
in tabulated form (not shown).
2. GENERAL ASSEMBLY
1. All parts,drawn in their operating position.
2. Part list (or bill of materials, BOM)
3. Leader lines with balloons around part numbers.
1. Item number
2. Descriptive name
3. Material, MATL.
4. Quantity required (per a unit of machine), QTY.
4. Machining and assembly operations and critical
dimensions related to operation of the machine.
REQUIRED INFORMATION IN
GENERAL ASSEMBLY DRAWING
23.
- Assembled parts
-Reference numbers
General notes
Title block
Part list
PLACING AN INFORMATION
(This course)
24.
PART LIST (BOM)(This course)
NO. PART NAME REQD. MATL. & NOTE
1 SUPPORT 2 Cast Iron
2 SHAFT 1 Stainless Steel
3 SET SCREW 1
Stainless Steel,
M3 HEX SOCK CUP PT
Locate above or beside the title block.
Fill the table from the bottom.
STEPS TO CREATE
ASSEMBLYDRAWING
4. Draw a view of major parts according to a
selected viewing direction.
3. Choose major parts, i.e. parts that have
several parts assembled on.
1. Analyze geometry and dimensions of all parts
in order to understand the assembly steps and
overall shape of device or machine.
2. Select an appropriate view.
27.
6. Apply sectiontechnique where relative
positions between adjacent parts are needed
to clarify.
7. Add balloons, notes and dimensions (if any).
5. Add detail view of the remaining parts at their
working positions.
8. Create BOM.
STEPS TO CREATE
ASSEMBLY DRAWING
28.
GENERAL PRACTICE
The numberof views can be one, two, three
or more as needed, but it should be minimum.
A good viewing direction is that represents all
(or most) of the parts assembled in their working
position.
29.
Part A PartB
EXAMPLE : Selection of a necessary view
Given
Student A Student B
Which is an appropriate view for assembly drawing ?
30.
GENERAL PRACTICE
Hidden linesare usually omitted unless they
are absolutely necessary to illustrate some
important feature that the reader might
otherwise miss.
31.
EXAMPLE : Hiddenlines omit or not ?
Part A
Part B
A
B
C
Good Poor
GENERAL PRACTICE
Section techniqueis usually needed to clarify
mating of the parts.
Correct
Better
Part A
Part B
OFF
Use different section line styles for adjacent parts.
ONColor
35.
Do not drawsection lines on sectional view of
standard parts.
- Threaded fastener
- Washer
- (longitudinal cut of) Solid shaft, Pin, Key
SECTION LINE PRACTICE
EXAMPLE : Sectionline practice
A
B
Good Poor
OFF ONColor
Which is an appropriate
section view of the joint ?
C
42.
LEADER LINE PRACTICE
Drawnin the oblique direction.
Drawn from the inside of the part to the balloon
and placed a filled circle at the beginning of a line.
1
2
1. Assemble steps.
2.Function of each part in machine.
3. Design concept.
INTERPRETING ASSEMBLY
DRAWING
45.
EXAMPLE 1 :Shaft support on a machine housing
Assemble steps
1. Install bearing to the shaft.
2. Install the bearing-shaft unit to
the housing.
3. Install the cover plate.
4. Tighten the screw.
46.
1. Bearing :
Supportthe rotating shaft.
2. Cover :
- Control an axial movement.
- Prevent the bearing unit from
rotation.
Functions of main parts
EXAMPLE 1 : Shaft support on a machine housing
47.
Avoid direct contactbetween
rotating shaft and housing as well
as cover plate by using a bearing
and clearance holes.
EXAMPLE 1 : Shaft support on a machine housing
Design concept
48.
1. Wrap apacking to the shaft.
2. Install studs to the casing.
3. Install the gland ring where its
holes align with stud.
4. Place the washer and
tightening the nut.
Packing
Casing
Gland
EXAMPLE 2 : Leakage prevention unit
Assemble steps
49.
1. Packing :
-Preventing the leakage of a
fluid inside the casing.
2. Gland :
- Press the packing to make it
radial expand and press the
shaft surface.
Packing
Casing
Gland
EXAMPLE 2 : Leakage prevention unit
Function
50.
Avoid direct contactbetween
rotating shaft and casing as well
as gland ring’s hole.
Packing
Casing
Gland
EXAMPLE 2 : Leakage prevention unit
Design concept
51.
EXAMPLE 3 :Fixing parts on a shaft.
1. Place the keys on the
key seats.
2. Insert the parts to the
shaft until their surfaces
lean against the shoulder.
3. Insert collar and then pin
or retaining ring into the
groove.
Assemble steps
52.
EXAMPLE 3 :Fixing parts on a shaft.
1. Key :
- Preventing rotational
movement of parts.
2. Pin and retaining ring :
- Prevent axial movement
of parts on the shaft.
Function
53.
EXAMPLE : Fixingparts on a shaft.
Retaining ring can resist
lower axial force than collar
& pin unit.
Design concept
54.
EXAMPLE : Partswith tapered holes on tapered shaft.
1. Insert the part on the
tapered end of the shaft.
2. Insert the washer
(non-standard).
3. Tightening the nut.
Assemble steps
55.
EXAMPLE : Partswith tapered holes on tapered shaft.
1. Washer :
- Improve the distribution
the tightening force on
the part.
Function
56.
EXAMPLE : Partswith tapered holes on tapered shaft.
Length of the tapered
portion and depth of the
tapered hole require a
calculation.
Design concept
57.
EXAMPLE : Partshaving preloaded spring
1. Insert the spring into the casing.
2. Tighten the rod to the spring
loader.
3. Close the cap and tighten.
Spring in
free length
Assemble steps
58.
EXAMPLE : Partshaving preloaded spring
1. Spring plunger :
- Transmit a force from rod to
spring.
- Keep the spring in a position.
Function
59.
EXAMPLE : Partshaving preloaded spring
Spring plunger has a spherical
surface contacts to the cap;
therefore, the rod can align itself
to original position.
Design concept
SURFACE FINISHING
1. Tocontrol the accuracy in positioning and
tightness between mating parts.
2. To reduce the friction, especially for the part
moves relative to other parts.
Surface finishing means the quality of a surface.
It relates to the level of roughness of a surface.
Purpose
63.
63
Surface Control
• Whydo we need to control surface
characteristics?
– Rough surfaces cause friction and wear
– It is difficult to make accurate measurements
from rough surfaces
64.
64
Surface Characteristics
• Roughness
–Small hills and valleys found on a surface
– Defined as the arithmetic average of the deviations
above and below a mean height of a surface
– Expressed in microinches or micrometers.
65.
• Waviness
– Surfaceirregularities greater than roughness
– Expressed in inches or millimeters
• Lay
– Direction of tool marks on a machined surface.
66.
66 Autumn 2009
.25inches
.125 inSurface Control Symbol
Material must be removed
Material must not be removed
Material removal not specified
67.
M
Parallel to linerepresenting surface
Perpendicular to the line representing the surface
Both directions to the line representing the surface
Multidirectional marks
Circular
Radial
Lay particulate, non-directional, protuberant
C
R
P
Bar added
Symbol
location
68.
24
Average roughness is0.000024 inches, which is
often referred to as 24 microinches or µinches.
Material must be removed.
28
14
Maximum average roughness is 28 microinches.
Minimum average roughness is 14 microinches.
Material must not be removed.
45
R
Average roughness is 45 microinches
Lines on the surface are radial with respect
to the center of the surface
69.
Assignment
• You areto complete the drawing and the
work sheets handed out.
• They are due on