Bearings - Concordia Universityusers.encs.concordia.ca/~nrskumar/Index_files/Mech211...– A hexagon inscribed into a given circle – A point on a segment that divides the line in

Bearings

Ball and roller bearings

Ball and roller bearings

Example of mechanisms

WORKING DRAWINGS

Production and Assembly

Documentation

Technical Data Presentation

Lecture 12

• Design process

• Technical documentation

• Working drawings

• Assembly working drawings

• Component working drawing

• Title block

• Modifications and revisions

• How to simplify the design process

• Checklist of a good design

• Technical data presentation

Content of the lecture

• Developed for a new product

• Includes working drawings apart from

calculations, technology details, assembly

scheme, etc.

• Working drawings include: • Assembly working drawings

• Component working drawing

• Component working drawings for the same

part may look different for different processes

Technical documentation

• One working drawing is made for each non-standard component

• All the necessary information to carry out manufacturing must be contained within the drawing

• Recommendation: use a reference (textbook) when draw a working drawing

• Assembly working drawing contain the necessary information to perform the assembly of the system

Working drawings

Working drawings

Working drawings

Working Drawings

• Includes assembly and

detailed specs for

manufacture

• Neatly made and checked

• Working drawings of

individual parts is called

detail drawing

• Details of individual parts may be drawn on single sheet or in many sheets

(one sheet per part), and assembly drawing done on separate bigger sheet

• If drawn on single sheet, space must be considered for dimensions and notes

as well

• In a detailed

drawing of an

assembly, the part

name and the

detail number are

located within the

drawing area

Detail Drawings

• A drawing must match a certain format

• The scale should be selected to make

sure that the component would fit the

format

• A preliminary evaluation should be

performed before the drawing is

completed

• Take into consideration the space for

dimensions

Drawing Form

back Drawing Form Refer front inside cover

of the book for details

Ion Stiharu

Drawing Form

• Used to record important information and keep track of the

parts a) Name and address of the company

b) Title of the drawing

c) Drawing number

d) Names of the designers and date of completion

e) Design approval

f) Additional approval

g) Predominant drawing scale

Title blocks and drawing #

h) Supply code for

manufacturers

i) Drawing sheet side

letter designation

j) Actual or estimated

weight of the item

Title blocks and drawing #

• Bill of Materials BOM -

consists of itemized list of

parts shown on a detail or

assembly drawing

• This is done above the

title strip (numbered

upward) or on separate

sheet

• It has the part numbers,

title, Qty, material and

other relevant info

• Drawing Numbers - all drawing should be numbered (lower

right or upper left corner of sheet) with serial numbers

indicating functionality of component or model No. of machine

• Revisions are required due to changes in design. So to keep track of all the modification, revisions need to be numbered and maintained

Modifications and Revisions

• The track of modifications is

kept on the drawing (some new

approaches are applied on CAD)

• If changes are considerable, new

drawing is made with

OBSOLETE stamped on old

1. Use text description whenever possible to eliminate

drawing completely.

2. Use text description whenever practical to eliminate

projected views.

3. Eliminate views where the shape can be given by

description e.g. HEX, SQ, DIA,

4. Show partial views of symmetrical objects.

5. Avoid elaborate, pictorial or repetitive detail.

How to simplify the design

process

6. When necessary to detail threads, do not show them

over the whole length.

7. Eliminate detail of nuts, bolt heads, and other standard

parts. Show outlines and position only.

8. Reduce detail of parts on assembly drawing.

9. Avoid unnecessary hidden lines that add no

clarification.

10. Use sectioning only when it is necessary for the clarity

of the drawing.


process

11. Simplify graphics for holes and tapped holes by use

of the symbols.

12. Omit views with no dimensional or written

instruction.

13. Within limits, a small drawing is usually easier and

quicker to make than a large one.

14. When two parts are slightly different, complete

graphical representation of both parts is not

required. The note: SAME AS EXCEPT …….. Or

OTHERWISE SAME AS …. may be given.


process

15. Drawings made to modify stock or commercial

parts should be as plain as possible. Avoid detail.

16. Use standard abbreviations whenever possible.

17. Whenever necessary, enlarge small details on

larger parts for clarity.

18. Draw small parts large enough to avoid crowding

so they may be easy to read, but not unnecessarily

too large to ware space on the drawing.

19. Do not duplicate dimensions.


process

20. Substitute recognized standard symbols, to simplify

greatly the drawing of common objects.

21. Eliminate repetitive data by use of general notes.

22. When drafting, do so much free-hand drawing as the

work permits, in preference to using instruments.

23. Where practical, use geometric symbols instead of

notes.

24. Where acceptable, give rectangular coordinate or

tabular dimensioning instead of dimension lines.


process

• Assembly drawing shows how each component is

positioned with respect to the others

• Each component should be identified and listed in a

parts list

• General assembly - gives a general graphic

description of the shape

• Sectioned assembly - shows the hidden features and

their interdependence

• Installation or outline assembly - indicates how the

parts, shown separated, are assembled

• Pictorial assembly - usually isometric, indicates how

the parts, shown separated, are assembled

Assembly Drawing

General Assembly Drawing

Detail

drawing of

a

automobile

connecting

rod

General Assembly Drawing

Assembly drawing of a

automobile connecting

rod

The purpose is relation

ship between parts in

assembly than

individual shape.

Minimum number of

views must be used.

Here one view is

enough to show the

relationship

This is also called a sub-assembly because this forms a part of

the bigger assembly

Sectional Assembly Drawing

Assembly drawing of a

Grinder

The purpose is relation

ship between parts in

assembly than

individual shape.

Minimum number of

views must be used.

Here (only) two views

are needed to show the

relationship

In order to avoid hidden lines (common due to interaction of many

components in assembly) sectioning is done to improve clarity

Sectional Assembly Drawing

• To distinguish parts,

section lines are

drawn in different

directions

• Change of angle (not

45°) may be done if

needed

• Thin materials like

gaskets are shown as

thick lines in section

• Standard practice is

not to section bolts,

shafts, even though

section lines pass

through them

Outline Assembly Drawing

• Made specifically to

show how to install

or erect a machine

• This is also called

installation assembly

• It outline the

relationships of

exterior surfaces

Outline Assembly Drawing • In aircraft drafting, installation assembly gives

complete information for placing details of

sub assemblies in their final positions in

airplane

Pictorial Assembly Drawing

• Made specifically to

show how to install

or erect a machine

• Here use of

isometric views to

show separated parts

that need to

assembled





Tabular drawing (catalog)

• Thus one

drawing serves

for a range of

sizes covered.

• But there is a

serious risk of

misreading the

table.

Is one on which the dimension are replaced by letters, and

accompanying table lists the corresponding dimensions for a series

of sizes

Standardized drawing

• Drawing is

made without

dimensioned

• Copied by any

methods

• Dimensions

filled

accordingly

To avoid misreading of tables as in tabular drawing, yet simplify

drawing process

1. Is the drawing easy to read?

2. Are the part outlines distinct from dimension lines?

3. Is the lettering neat and clear?

4. Is all of the information on the drawing?

5. Will the drawing make a good print?

6. Have all the rules of standard drafting practices

been followed?

Checklist for a good design

7. Is the nomenclature correct? Will anyone

understand it the same way?

8. Is the drawing title truly descriptive?

9. Are all the necessary views given?

10. Are all the dimensions shown?

11. Are dimensions which are given twice?

12. Are all the notes properly located?

13. Could any of the notes be misunderstood?


14. Does the parts agree with the list?

15. Are the standard parts specified correctly?

16. Is the scale designated?

17. Are the finishes specified in the drawing?

18. Is heat treatment recommended?

19. Have standard manufacturing processes been

followed?

20. Can the part be produced simpler and more

economic?


21. Are the materials specified?

22. Are the standard parts used to the maximum

extent?

23. Are the suppliers for the standard parts indicated?

24. The design is yours. Are you ready to approve it?


Review

Exam Related Discussion and sample

problems

Lecture 13

Introduction to graphic language and design — means and

techniques. The third and the first angle projections.

Orthographic projection of points, lines, planes and solids.

Principal and auxiliary views. Views in a given direction.

Sectional views. Intersection of lines, planes and solids.

Development of surfaces. Drafting practices. Dimensioning,

fits and tolerancing. Computer-aided drawing and solid

modelling. Working drawings — detail and assembly

drawing. Design practice. Machine elements representation.

Case Study

Content of the Course

• Multi View Drawings

• you need to practice imagination and try doing some

missing line problems and other views given in the book

• You can also work on the example problems in the

slides.

• To help you do this, you can look at the following

website

• http://www.prenhall.com/giesecke (the website given in

the book)

Lecture 1

http://www.prenhall.com/giesecke

• Graphic constructions

– Line perpendicular to a segment passing through the middle

point

– Bisection line of an angle

– Tri-section lines of a 90° angle

– A hexagon inscribed into a given circle

– A point on a segment that divides the line in a given ratio

– Laying out an angle, transfering triangle

– Arc tangent to lines and arcs

– And other things that you see in the book as well

Lecture 2

• Sectional Views

– Full Sections, Half Sections

– Offset Sections

– Broken Sections

– Revolved Sections

• Sections through assemblies

– Do not section, shafts, bolts etc and other objects like ribs,

webs ….

– Attention to direction of section lines

– Thin objects (gaskets, seals…) are sectioned (filled) with thick

lines

– Rotate objects to avoid to improve clarity, when odd number of

spokes in a cirle etc…..

Lecture 3

• Auxiliary Views

– Primary aux view

– Depth, width and height aux view

– Folding line method

– Always take the projection lines in the direction of view, and

take the distances from the previous view

• Secondary aux view

– Drawn from the primary aux view

Lecture 3

• Particular positions of a line – horizontal, frontal or profile

• True length of a line – selected auxiliary views

• Bearing of a line (in the top view, N(S) nn E(W)

• Slope of a line (from the top view, draw a TL in aux view – elevation

view

• Point view of a line – second aux. View (first aux view to get TL)

• Relative position of a point vs. a line (to see if point is on the line or

not)

• Relative position of two lines (//, X or skew)

• Parallel lines; rule of parallel lines (exceptions) always seen parallel

except when they are perpendicular to the folding line you need the

third view

Lecture 4

• True distance between two parallel lines

– See the lines as points and find the distance between them

• Intersecting lines – identification through inspection

• Skewed lines – visibility drawn from adjacent view

• Perpendicular lines – rule of perpendicular lines

– A 90° angle appears in true size in any view showing one leg in

TL provided the other leg does not appear as point view

– Two intersecting lines are perpendicular if the TL projection is

making 90° with the other line

Lecture 4

• Distance form a point to a line

– Perpendicular to line and from the point is the shortest distance

– Go to the point view of the line and project the point too.

– Draw line between the 2 points and it has to be parallel to the

FL and 90° to the line (the distance is the TL line)

– Project the line in all the views

• Location of a perpendicular line at a give location on a line

– Same as above, find the point view of the line

– You can have multiple solutions unless a direction is given

– If direction given, Draw line from the point in that direction

– Adjacent view has to be parallel to the FL and 90° to the line

and it should be where the point is

– Project this line in all the views

• Checking for Skewed lines

– If point cannot be transmitted to adjacent views

Lecture 5

• Shortest Distance between 2 skewed lines

– Perpendicular to line and from the point view of the other line is

the shortest distance

– Go to the point view of one line and project the other line too.

– Draw line between the points and the line at 90° and it has to

be parallel to the FL and 90° to the line (the distance is the TL

line)

– Project the line in all the views

• Location of a line through a point intersecting 2 skewed lines

– Construct a plane with one line and the point

– Use cutting plane method to find the piercing point

– Draw a line from the piecing point to the given point and extend

it to the other line in the problem

Lecture 5

• Strike of a plane

– Bearing of a TL line in the plane is the strike of the plane

• Edge View of a plane

– Draw TL line (draw a line parallel to the FL in one view and

project the points of intersection with the plane to the adjacent

view)

– If you see the TL as point, you will see the plane as an edge

• Slope or dip of a plane

– The angle that the EV of a plane makes with the horizontal FL

• Shortest line from point to plane

– Find the EV of the plane and project the point as well

– Draw a line 90° to the plane from the point and make it TL by

Tracing back with perp from TL in the adjacent view.

– For the next view use the distance from the folding line

Lecture 5

• Shortest horizontal and grade line from point to plane

– Same as previous but the lines should have an angle parallel to

the horizontal FL for horizontal line or parallel to a line which is

at a given angle to horizontal FL for grade line

– Make it TL by Tracing back with perp from TL in the adjacent

view.

– For the next view use the distance from the folding line

• True shape of a plane

– Secondary aux view adjacent to the edge view of the plane

– Used to find TS of oblique surfaces or centre of oblique circle

etc…

• Angle of line with oblique plane

– Line in TL and plane in EV.

– First get the EV and project the line. Next get the TS of the

plane

– Next get the TL of the line in third aux view

Lecture 5

• Angle between intersecting lines in a plane

– Can be found if the plane is in its TS

• Dihedral angle

– Find the line of intersection between the planes

– Get the TL of the intersection line and its point view

– In that view you will see the planes as EV and angle is dihedral

angle

• Angle of line with oblique plane

– Line in TL and plane in EV.

– First get the EV and project the line. Next get the TS of the

plane

– Next get the TL of the line in third aux view

Lecture 6

• Shortest line between 2 skewed lines EV method

– Create a plane with one line and parallel to the other line

– EV of the plane will give 2 parallel lines. (distance (90°) between these

lines is the shortest distance

– Draw secondary aux view to see the lines as TL and they will intersect

at a point

– Project this point back to views that will give you the line in all views

• Shortest horizontal and Grade line between 2 skewed lines - EV

method

– Same as previous except point 3

– Aux views are drawn parllel to horizontal FL for horizontal line and

parallel to a line drawn at a given angle to the horizontal FL

– Project this point back to the views

• Line intersecting a plane

– If line is not parallel to plane it should intersect (piercing point)

Lecture 6

• Piercing Point - CP Method

– Draw a CP whose EV coincides with the line in any one view

– Project the points of intersection with the lines in the plane to the

adjacent view

– Draw a line between these points and find the intersection of this line

(which is the projection of the cutting plane) with the original line

– This gives the piercing point in that view. Project this point to the line

on the adjacent view

– For visibility get the information from the adjacent view

• Piercing Point - EV Method

– Draw the EV of the plane and project the line in that view

– Find the point of intersection and project the point back to the line in

the views

Lecture 6

• Intersection of Planes EV method

– Find EV of one plane project the other plane in that view

– You will get 2 piercing points in that view

– Project the points back to the corresponding lines in the views and

complete the line of intersection

• Intersection of Planes - CP Method

– Coincide the EV of CP with one of the lines in one plane and find one

piercing point in both views

– Repeat with another cutting plane and find the other piercing point

– Join these two to get the line of intersection

Lecture 6

• From lectures 7 to 9, all the points regarding the construction for

intersections and developments are clearly given next to the

drawing itself, on the slides

Lectures 7 - 9

Sample Problems

1. Missing views, auxiliary views, Section views

2. Missing views, auxiliary views, Section views

3. Points, lines and Planes

4. Points lines and Planes

5. Intersection or Development

6. Abstract design problems

• Note: All questions carry equal marks and no materials

allowed except drawing instruments and calculator

Exam Logistics

Concordia UniversityDepartment of Mechanical and

Industrial Engineering

Midterm Exam

Name and Surname I.D.#

110 Minutes Problem #1

29 Oct 2012 10 Marks

MID TERM EXAMINATION MECH 211, FALL 2012

Answer on the same sheet where the questions are. Closed book

examination. It is an exam, not group work.Total time for the midterm

examination is 110 minutes. Total value of the Midterm Exam is 40 marks

1. Given 3 points, draw the circle that passes through this points. Mark the

diameter of that circle on the drawing.

2. Draw arcs of 25mm diameter tangential to both these circles on circles

on either side

3. Inside the smaller circle there is a hexagon centrally inscribed in a circle

of dia 25mm. The sides of the hexagon has to be parallel to the

horizontal direction



Midterm Exam


110 Minutes Problem #1

29 Oct 2012 10 Marks

MID TERM EXAMINATION MECH 211, FALL 2012

Answer on the same sheet where the questions are. Closed book

examination. It is an exam, not group work.Total time for the midterm

examination is 110 minutes. Total value of the Midterm Exam is 40 marks

Ø3.0000

Ø2.0000

1. Given 3 points, draw the circle that passes through this points. Mark the

diameter of that circle on the drawing.

2. Draw arcs of 25mm diameter tangential to both these circles on circles

on either side

3. Inside the smaller circle there is a hexagon centrally inscribed in a circle

of dia 25mm. The sides of the hexagon has to be parallel to the

horizontal direction



Midterm Test


Date: 29 Oct 2012

Problem # 2

10 Marks

A

Given the Front, Top and Isometric view of the object, draw the :

1. Missing Right Side View at the appropriate position

2. Parital auxiliary view to show the true shape of the surface 'A'

Draw the Isometric View here Draw the Partial Auxiliary View here

Time: 110 Mins



Midterm Test


Date: 29 Oct 2012

Problem # 2

10 Marks

A





Time: 110 Mins



Midterm Test


Time: 110 Mins

Date: 29 Oct 2012

Problem # 2

10 Marks

64.7858

45.7311

A





Given the partial FV and SV, complete Drawing the Front View with the

revolved section of the spoke, and Right Side View with full section

Also show the section line on the drawing

29 Oct 2012

Problem # 3110 Minutes

I.D.#Name and Surname

Midterm ExamConcordia UniversityDepartment of Mechanical and


10 Marks




29 Oct 2012





10 Marks




29 Oct 2012





10 Marks



Midterm Exam


110 Minutes Problem # 4

29 Oct 2012

S

A

A

S

10 Marks

Views of points A and S are given.

a) Draw a line AB such that B is 100mm to the right of, 50mm

below and 50mm behind A

b) Find the bearing and slope of line AB

c) What's the shortest distance between Point S and Line AB

Hint: use the Arrow point for intersection of

aux fold lines. Also the arrow points North



Midterm Exam



29 Oct 2012

B

S

A

A

S

B

10 Marks








N63E



Midterm Exam



29 Oct 2012

B

S

A

A

S

B

10 Marks

24°








N63E



Midterm Exam



29 Oct 2012

B

S

A

A

S

B

10 Marks

24°








N63E

A,B

S15.5

FH

The solution can be found based on the print-out of this question. In the

first auxilary view, find the point d on line c-e and with a length of 20

mm. Project point d back to the top view and the front view. The bearing

of line b-d can be then found.

Given the front and top views of a plane, a-b-c. Question: (1) starting from

point c, draw a declined line, c-d, with a true length of 20 mm and

parpendicular to the plane a-b-c; and (2) connect points b and d and find

the bearing and slope of the line b-d.

c

cb

b

a

a

Problem #Date:


Midterm TestConcordia UniversityDepartment of Mechanical and


Sample Problems

e

e

FH









c

cb

b

a

a

Problem #Date:




d

d

d

e

e

e

c

1H

FH









c

cb

b

a

a

Problem #Date:




38°db

S61°W

d

d

d

e

e

e

c

1H

FH









c

cb

b

a

a

Problem #Date:




F

H

Edge view of the circle with quadrants abcd is given in the

top view. Draw the missing views and the auxiliary view

to show the true size of the circle and mark its diameter.

aH

cH

bHdH

Problem #Date:


Final ExamConcordia UniversityDepartment of Mechanical and


Sample Problems

PF

AH

F

H

R1.0000

Edge view of the circle with quadrants abcd is given in the

top view. Draw the missing views and the auxiliary view

to show the true size of the circle and mark its diameter.

aA

dA cA

bA

aFcF

dF

bF

aH

cH

bHdH

aPcP

dP

bP

Problem #Date:




Sample Problems

The top view of the Throttle Body is given.

Draw the full sectional front view using the guide in

dotted line and the auxiliary view for height details.

Follow the conventions of drawing sectional views.

Problem #Date:




Sample Problems



Final Exam


Date: Problem #

The top view of the Throttle Body is given.

Draw the full sectional front view using the guide in

dotted line and the auxiliary view for height details.

Follow the conventions of drawing sectional views.

Sample Problems

1 6 2 5 4 3

1

6

25

43

1 62 5

43

1 6 2 5 4 3

1

6

25

43

1 62 5

43

1 6 2 5 4 3

1

6

25

43

1 62 5

43

1 6 2 5 4 3

1

6

25

43

1 62 5

43

Documents

Bearings - Concordia Universityusers.encs.concordia.ca/~nrskumar/Index_files/Mech211...– A hexagon inscribed into a given circle – A point on a segment that divides the line in