COMPUTER AIDED MACHINE DRAWING Lab Manual-2017 - 1 PDF
COMPUTER AIDED MACHINE DRAWING Lab Manual-2017 - 1 PDF
COMPUTER AIDED MACHINE DRAWING Lab Manual-2017 - 1 PDF
com
Prof.J.Bharani Chandar Prof. S.Muthukumarasamy Prof.S.K.Nagoor vali
S
DEPARTMENT OF MECHANICAL ENGINEERING
LAB MANUAL
2017 Regulation
Subject Code : ME 8381
Year/Semester : II/III
Authors
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Prof.J.Bharani Chandar Prof. S.Muthukumarasamy Prof.S.K.Nagoor vali
OBJECTIVES:
Note: 25% of assembly drawings must be done manually and remaining 75% of assembly drawings
must be done by using any CAD software. The above tasks can be performed manually and using
standard commercial 2D / 3D CAD software
OUTCOMES:
Upon the completion of this course the students will be able to
CO1 Follow the drawing standards, Fits and Tolerances
CO2 Re-create part drawings, sectional views and assembly drawings as per standards
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VELTECH
(Owned by R.S. Trust)
(Approved by AICTE, New Delhi & Affiliated to Anna University, Chennai)
LAB MANUAL
NAME :
DEG/BRANCH :
UNIVERSITY REG NO :
VT NO :
YEAR :
SEMESTER :
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Prof.J.Bharani Chandar Prof. S.Muthukumarasamy Prof.S.K.Nagoor vali
VELTECH
(Owned by R.S. Trust)
(Approved by AICTE, New Delhi & Affiliated to Anna University,
Chennai) No 60, Avadi-Vel Tech Road, Chennai – 600 062.
CERTIFICATE
Name……………………………………………………………………………………
Year ……………………….Semester……………………….Branch………………….
Certified that this is a bonafide record of work done by the above student in the
“ME 8381 COMPUTER AIDEDMACHINE DRAWING LABORATORY” during
the year 2018 – 2019.
DATE:
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Prof.J.Bharani Chandar Prof. S.Muthukumarasamy Prof.S.K.Nagoor vali
CONTENTS
Ex.
Name of the Exercise Page No
No
14 Exercise of Extrusion 53
15 Exercise of Revolve 56
16 Exercise of Rib 58
17 Exercise of Shell 60
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Ex.
Name of the Exercise Page No
No
22 Assembly and Sleeve and Cotter Joint 67
32 Assembly of Piston 88
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SYLLABUS
OBJECTIVES:
• To make the students understand and interpret drawings of machine components
• To prepare assembly drawings both manually and using standard CAD packages
• To familiarize the students with Indian Standards on drawing practices and standard components
• To gain practical experience in handling 2D drafting and 3D modeling software systems.
Note: 25% of assembly drawings must be done manually and remaining 75% of assembly drawings
must be done by using any CAD software. The above tasks can be performed manually and using
standard commercial 2D / 3D CAD software
OUTCOMES:
Upon the completion of this course the students will be able to
CO1 Follow the drawing standards, Fits and Tolerances Re-create part drawings,
CO2 sectional views and assembly drawings as per standards
TEXT BOOK:
1. Gopalakrishna K.R., “Machine Drawing”, 22nd Edition, Subhas Stores Books Corner, Bangalore,
2013
REFERENCES:
1. N. D. Bhatt and V.M. Panchal, “Machine Drawing”, 48th Edition, Charotar Publishers,2013
2. Junnarkar, N.D., “Machine Drawing”, 1st Edition, Pearson Education, 2004
3. N. Siddeshwar, P. Kanniah, V.V.S. Sastri, ”Machine Drawing” , published by Tata Mc
GrawHill,2006
4. S. Trymbaka Murthy, “A Text Book of Computer Aided Machine Drawing”, CBS Publishers, New
Delhi, 2007 www.Vidyarthiplus.com
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AIM:
To study the code for engineering drawing
(i) ABBREVATIONS
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RESULT:
Thus the code and symbols of practice for Engineering drawing were studied.
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Date:
Aim:
To study the welding symbols.
INTRODUCTION
The position of the arrow line with respect to the weld is of no special significance. The side of
the joint on which the arrow line is drawn is called “arrow side”. The side of the joint remote to the
arrow line is called “other side”. The reference line has significance on the weld side. If the weld
symbol is placed BELOW the reference line, the welding should be done in the “ARROW SIDE”. If
the weld symbol is placed ABOVE the reference line, the welding should be done in the “OTHER
SIDE”. If the weld symbol is placed both ABOVE and BELOW the reference line, the welding
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should be done in both the “ARROW AND OTHER SIDES”.
The basic symbols recommended by Bureau of Indian Standards (BIS) for specifies the type
Size of weld
The size of the weld is height of the isosceles triangle in the case of fillet welds. In
other cases, the size will be the minimum distance from the surface of the paert of the bottom
of penetration.
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a. Flat (flush)
b. Convex
c. Concave
Finishing welds other than cleaning shall be indicated by
finish symbols. Chipping – C, Grinding – G, Machining – M
Site weld
When some of the welds (the welded structures) are required to be made on site during
erection. They should be designed by a filled in circle at the point connecting the arro w and
RESULT:
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Aim:
To study the riveted joints.
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Various types of rivet heads for the use in general engineering work and boiler work as
recommended by the Bureau of Indian Standards. The different proportions of these rivet heads
are given in terms of the nominal diameter d of the rivet. The rivet head to be used for general
purposes for diameter below 12 mm are specified in the Indian Standard code IS:2155-1962 and
for diameters between 12 and 48 mm are specified in the Indian Standard code IS:1929-
1961. The rivet heads to be used for boiler work are specified in the Indian Standard code IS:
1928-1961. The rivet heads to be used for ship building are specified in the Indian Standard
code IS: 4732-1968.
RESULT:
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Date:
Aim:
SCREW THREADS
INTRODUCTION
A screw thread is a functional element used on bolt, stud, set screw, nut or any other threaded
piece or component. Screw thread is a helical groove on a cylinder surface (outer side or inner
side). Its function is to transform the input motion of rotation into output motion of translation.
If a cylindrical rod is rotated at a constant speed simultaneously if a pointed tool touching the
rod moving parallel to the axis of the rod at constant speed, the cut made by tool on the rod will be
continuous and of helical form. The helical groove is called “thread” and the threaded rod is called
a “screw”.
Threads are cut using a lathe. Small size thread is often cut by means of a tool called die. A
small size hole is threaded by means of a tool called a tap.
The principal uses of threads are,
1. For fastening
2. For adjusting
3. For transmitting power
3. Flank or side: It is the surface of a thread that connects the crest with the root.
4. Angle of the thread: It is the angle included between the sides of two adjacent Threads
measured on an axial plane.
5. Depth of the thread: It is the distance between the crest and the root measured at Right angle to
the axis. It is equal to half the difference between the outer diameter and the core diameter.
6. Major diameter or outside diameter: It is the diameter of the imaginary coaxial cylinder, which
would bind the crests of an external or internal thread.
7. Minor or core or root diameter: It is the diameter of the imaginary coaxial cylinder, This
would bind the roots of an external thread or of an internal thread.
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8. Pitch diameter: It is the diameter of the imaginary coaxial cylinder that can be Passed so as to
cut the thread, that the width of the cut thread will be equal to the Width of the groove.
9. Pitch: It is the axial distance between a point on one thread and the corresponding Point on the
next thread. It may be indicated as the distance from crest or from root of two adjacent threads.
10. Lead: It is the distance measured parallel to the axis from a
point on a thread to
The corresponding point on the same thread for one complete revolution. In other words, it is axial
distance a screw advances in one revolution. When all the threads on a member are built on a single
helix it is termed as “single start thread”. It has only one starting point. For a single start thread, the
lead and pitch are same.
If a quick acting thread is needed, the lead must be large. If a single start is cut with large pitch,
the thread depth will also be more, so the amount of material removed is more and the thread will be
weakened. To avoid this multiple threads are used when a quick advance is required in a screw pair.
Two or more threads are cut side by side around the cylinder on an equal number of parallel helices. It
is termed as “Multi start thread”.
Lead = number of starts x pitch
A common example for multi start thread is the thread on a fountain pen cap.
11. External thread: It is the thread on the outside surface of a member such as bolt, Studs or screw.
12. Internal thread: It is the thread on the inside surface of a member such as nut or Threaded hole.
13. Right hand thread: Right hand thread if turned clockwise direction advances into a Threaded hole.
It abbreviated as RH.
14. Left hand thread: Left hand thread if turned anticlockwise direction advances into a threaded hole.
It abbreviated as LH.
Threads are standardized to permit to interchangeability of bolts and nuts of the same nominal diameter.
The profile of a screw thread is based on its use. The two main kinds are „V‟ and square with various
modifications. When the thread has a „V‟ cross-section it is called a „V‟ thread and when it has square
cross section it is called a square thread.
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DIFFERENCE BETWEEN „V‟ AND SQUARE THREADS
V- THREADS
This thread was introduced by Sir Joseph whit worth, and was standardized as British standard
thread. It has a thread angle of 55 degree and is rounded equally at crest and roots.
British Association threads (B.A Threads)
The angle between flanks is 47.5 degree. These threads are to supplement BSW and have fine pitches.
They are used on screws for precision work.
The thread angle is 60 degree and both the crests and roots are kept flat. The sellers thread has
been in use in USA and Canada.
The countries UK, U.S.A and Canada came to an arrangement for a common screw thread
system with the included angle of 60 degree and designated as unified screw thread in the year
1949.
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The thread on the bolt is rounded off at the crest and root and the thread in the nut is rounded off
at the root but the crest is left flat.
This thread is very important in the motor and aeroplane industries and in chemical engineering.
Unified thread can be either coarse (UNC) or fine (UNF) and unified national extra fine (UEF).
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This is Indian standard thread for ISO (International Standard Organization). The included
angle is 60 degree and the crests are flat and roots are round.
Metric threads are grouped into diameter pitch combination differentiated by the pitch applied
to specific diameters. There are coarse, constant, fine pitch series available.
ISO metric threads are defined by nominal size (Basic major diameter) and pitch both
expressed in millimeters. For example, a 10mm diameter, 1.25 pitches is expressed as
M10x1.25.
SQUARE THREADS
The sides of these threads are normal to the axis and parallel to each other. The depth and the
thickness of the thread are equal to half pitch. A square thread is designated by the letter SQ
followed by nominal diameter pitch. For example a square thread of nominal diameter 30mm
and pitch 6mm is designated as SQ 30 X 6.
Acme Thread
It is a modified from of square thread. It is easier to cut and is much stronger than square thread.
It has a 29 degree thread angle. This inclined sides of the thread facilitate quick and early
engagement and disengagement. It is used for power screws like lead screw of lathe, jackscrews,
bench vices and valve operating screws.
Buttress Thread
The profile of this thread is a combination of square and V- threads. It combines the low
frictional of square and ability to transmit power of square thread and the strength of V –
thread. It is used to transmit load in uni-direction. These threads are used in screw press, vices.
Knuckle Thread
It is also a modification of square thread. The sharp corners of square thread are rounded off.
This thread is used where heavy wear rough use is expected. The thread can be rolled or cast
easily. It is used in railway carriage coupling screws, light bulbs and sockets, bottle caps etc
and also objects made of brittle materials as glass, plastic, porcelains etc.
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KEYS
Introduction:
A machine runs by the power supplied to it by a prime mover such as motor, engine etc;. This
power is transmitted from prime mover to the machine through a coupler which couples shaft of
the prime mover and the machine. Within the machine the power from the main shaft is
transmitted to the other elements such as gears, pulleys and belts. These elements have to be
mounted on these shafts and there should not be any relative motion between the machine
element and shaft for effective power transmission. The most commonly employed method to
connect a shaft and a machine parts is to drive a small piece of metal s known as KEY. To drive
a key axial grooves are cut both in the shaft end the part mounted on it. The groove in the shaft
is called the “KEYWAY”.
CLASSIFICATION OF KEYS:
1. Taper keys
mm W = Width of the
key T = thickness of the
key W = 0.25D+2mm
T = 0.66W
Standard taper = 1:100
Saddle key:
Saddle keys are of two types
a. Hollow saddle key
b. Flat saddle key
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THREADED FASTENERS
INTRODUCTION
Threaded fasteners are temporary fasteners, which hold the parts together through the medium
of a screw thread. These are used in pairs for their action (for examp le, a nut and a bolt).
They have the advantage over permanent fasteners of allowing assembly of parts when
required. A wide variety of threaded fasteners are in use. Some of them are standardized and
others are made for special use.
BOLTS
A bolt is a metal having a head at one end and a threaded portion to a definite length on
other end. The head is formed by forging or machining. The bolt is admitted through holes in
the parts, which are to be fastened. The projected thread end of the bolt admits a
corresponding nut from the other side. Tightening the bolt by turning gives necessary
clamping grip to hold the parts together.
Bolts and nuts of various shapes are used for different purpose but the hexagonal head
and square head are very common. Although, the square shape provides better spanner grip
than the hexagon, but needs one fourth of a turn to bring it into the same position for inserting
spanner again, whereas a hexagon need only one sixth of a turn and hence provided.
The sharp corners on the external flat end faces of bolt heads and nuts are chamfered conically
at 30ᴼ to ensure safety of the user. To facilitate early insertion of the nut over the bolt, the
threaded holes in the nut are countersunk. Three dimensions are usually sufficient for
simplified representation of a bolt The bolt shank diameter (d) The bolt length (l) The length
of a threaded portion of the shank (b)
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STEP: 4
The two face view of the bolt head and nut is as follows. The width of the bolt head in this
view is equal to the across flats width. Draw an arc radius equal to half of the across flats
width from the point O1. Two arcs with radius equal to across flats width from the corners.
These two arcs cut the first arc at two points 02 and 03. From 02 and 03 the chamfer arcs are
drawn.
Drawing of Square Head Bolt And Nut:
STEP: 1
Draw the shank of the bolt equal to the given diameter d and the length of the bolt. The
thickness of the bolt head is equal to 0.8d and the thickness of the nut is equal to 0.9d are
marked. The right hand view of the bolt and nut assembly is drawn as follows. With any point
01 on the axis as centre and diameter equal to 1.5d+3mm draw a chamfer circle with its sides
inclined at 45degree to the axis. Project the corners 1 and 2 to get to get point‟s p.
STEP: 2
From the point 01 draw an arc radius equal to half of the across corners width. From the
corners, draw two arcs radius equal to half of the across corners width. These two arcs cut the
first arc at two points 02 and 03. From 02 and 03 the chamfer arcs are drawn.
STEP:
The chamfer line is drawn at 30degree to the flat face of the bolt head and nut. The threaded
portion on the shank of the bolt is indicated by drawing two thin line spaced at a distance
equal to the root diameter d1=0.9d. The root circle in the right view is represented by a thin
three-fourth of a circle with center 01 and diameter 0.9. The end of the bolt is chamfered to
0.1d*45degree.
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Cup Or Round Headed Bolt:
Two types of cup head bolts are available. In one type, a snug is provided which prevents the
rotation of bolt head. The other type, a square neck is provided which will fit into the square
hole provided in the bearing surface and thus prevents the rotation of the bolt head.
I-Head Bolt:
The head of this bolt is like letter „i‟. These bolts are used in bearing housing and in glands
packing. These bolts are used in setting work on machine tool tables. The i head of the bolt
can slide, to the required position through the i slots cut on the m/c table.
Eye Bolt:
The head of the bolt is in the form of circular form of rectangular cross section. It is generally
used in the inspection covers, lids etc..., Which have to be opened and closed frequently.
Hook Bolt:
The hook bolt has its head comprising of a square neck and projection. The shank of the bolt
passes through a hole in one of the fastening pieces and the other piece comes under the bolt
head and is supported by it.
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NUTS
A nut is a device having internal threads used in combination with a bolt or stud, having
external threads to fasten parts together. It is screwed on the threaded end of the bolt or stud
and the head of the bolt is drawn closer to hold and tighten the parts to be joined.
Nuts are usually made in form of hexagonal or square prism, however various other types of
nuts are also used for the specified purposes, which are suitable for a particular type of work.
These special types of nuts are described here.
KNURLED NUT
It is cylindrical nut with knurled curved surface. The nut is used when finger tightness and
quick turning on or off is desired as in the case of terminals of electric apparatus.
WING NUT:
This type of nut is used for light duty only. It is used wherever the nut is required to be
frequently turning on or off. The nut is operated by thumb and finger i.e., without the use of a
spanner. The main objection for using this type of locking is that the hole drilled in the bolt
reduces its strength considerably.
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Prof.J.Bharani Chandar Prof. S.Muthukumarasamy Prof.S.K.Nagoor vali
The other equally important objection is that after continuous use owing to the stretch of the
bolt the split pin may not rest on the top face of the nut which may reduce the locking effect.
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LOCKING BY A LOCK PLATE:
This type of locking is employed in the heavy engineering work, as in the case of
connecting rod, wheel shafts etc. the plate is grooved in such a way that the grooves in the
plate receive the hexagonal corners of the nut at every 30˚ rotation. The plate is fixed to the
bearing surface by a tap bolt screwed into it.
SET SCREWS
Setscrews are used as semi permanent fasteners to hold a collar, sleeve, pulley or on a
shaft against rotational or translation forces. In contrast to most fastening device, the setscrew
is essentially a compression device. Forces developed by the screw point during tightening
produce a strong clamping action that resists relative motion between assembled parts. The
basic problem in setscrew selection is in finding the best combination of setscrew form, size,
and point style providing the required holding power. Set screws are categorized by their form
and the desired point style. Selection of specific, form or point is influenced by functional by
functional, as well as other considerations.
The conventional approach to setscrew selection is usually based on a rule of thumb
that the setscrew and key are used together; the screw diameter should be equal to the width
of the key.
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Prof.J.Bharani Chandar Prof. S.Muthukumarasamy Prof.S.K.Nagoor vali
CAP SCREW
Cap screws are similar to bolts in that they have a head on one threads on the other.
But they widely in the method of holding two parts together. The bolt keeps two parts between
the head and the nut, and the cap- screw is threaded in one of the parts, thus clamping another
part between the head threaded part. The cap screws are manufactured in several styles of
head. The point of all cap screw is flat surface and to a depth equal of the threaded on it.
MACHINE SCREWS
These are similar in function and operation to cap screws, but are usually smaller in
diameter. Materials: for general engineering purpose, nuts and screws are made of mild steel
(MS). However, copper and its alloys, aluminum alloys, etc are also alloys, etc are also used
for also used for special purpose in their manufacture.
FOUNDATION BOLTS
For securing heavy machines to concrete foundations, special types of bolts known as
foundation bolts are used. Positions of bolt holes are marked either from a temple or from a
template or from the machine itself, and holes bored out in the floor, sufficiently large enough
to allow the bolt to be suspended freely in positions while the cement concrete is poured
around to fill up the space. When the cement concretes sets the bolt will be firmly secured in
the ground.
RESULTS:
Thus the studies of Screw threads, keys and fasteners were studied.
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The manufacture of interchangeable parts require precision. Precision is the degree of accuracy to
ensure the functioning of a part as intended. However, experience shows that it is impossible to make parts
economically to the exact dimensions.
This may be due to,
(i) inaccuracies of machines and tools,
(ii) inaccuracies in setting the work to the tool, and
(iii) error in measurement, etc.
The workman, therefore, has to be given some allowable margin so that he can produce a part, the
dimensions of which will lie between two acceptable limits, a maximum and a minimum.
The system in which a variation is accepted is called the limit system and the allowable deviations are
called tolerances. The relationships between the mating parts are called fits. The study of limits, tolerances
and fits is a must for technologists involved in production. The same must be reflected on production
drawing, for guiding the craftsman on the shop floor.
LIMIT SYSTEMS:
Following are some of the terms used in the limit system :
Tolerances:
The permissible variation of a size is called tolerance. It is the difference between the maximum and
minimum permissible limits of the given size. If the variation is provided on one side of the basic size, it is
termed as unilateral tolerance.
Similarly, if the variation is provided on both sides of the basic size, it is known as bilateral tolerance.
Limits:
The two extreme permissible sizes between which the actual size is contained are called limits. The
maximum size is called
the upper limit and the minimum size is called the lower limit.
Deviation:
It is the algebraic difference between a size (actual, maximum, etc.) and the corresponding basic size.
Actual Deviation:
It is the algebraic difference between the actual size and the corresponding basic size.
Upper Deviation:
It is the algebraic difference between the maximum limit of the size and the corresponding basic size.
Lower Deviation:
It is the algebraic difference between the minimum limit of the size and the corresponding basic s ize.
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Allowance:
It is the dimensional difference between the maximum material limits of the mating parts,
intentionally provided to obtain the desired class of fit. If the allowance is positive, it will result in
minimum clearance between the mating parts and if the allowance is negative, it will result in
maximum interference.
Basic Size:
It is determined solely from design calculations. If the strength and stiffness requirements need a
50mm diameter shaft, then 50mm is the basic shaft size. If it has to fit into a hole, then 50 mm is the
basic
size of the hole. Figure 15.1 illustrates the basic size, deviations and tolerances. Here, the two
limit dimensions of the shaft are deviating in the negative direction with respect to the basic size
and those of the hole in the positive direction. The line corresponding to the basic size is called
the zero line or line of zero deviation
Design Size:
It is that size, from which the limits of size are derived by the application of tolerances. If there is
no allowance,
the design size is the same as the basic size. If an allowance of 0.05 mm for clearance is applied, say to a
shaft of 50 mm diameter, then its design size is (50 – 0.05) = 49.95 mm. A tolerance is then applied to
this dimension.
Actual Size:
It is the size obtained after manufacture.
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TOLERANCES:
Great care and judgement must be exercised in deciding the tolerances which may be applied on various
dimensions of a component. If tolerances are to be minimum, that is, if the accuracy requirements are
severe, the cost of production increases.
In fact, the actual specified tolerances dictate the method of manufacture. Hence, maximum possible
tolerances must be recommended wherever possible.
Table: Systems of indication of tolerances of form and of positions
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RESULTS:
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Prof.J.Bharani Chandar Prof. S.Muthukumarasamy Prof.S.K.Nagoor vali
Ex. No. 6 Preparation of production drawings and reading of part
and assembly Drawings
Date:
Aim:
To draw the following production and Assembly drawings in the A3 sheet using standard
principles of drawing.
Fig. Template
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Prof.J.Bharani Chandar Prof. S.Muthukumarasamy Prof.S.K.Nagoor vali
Diagram-1 - Crank
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Result:
Thus the production drawings and Assembly drawings were drawn
manually in A3 drawing sheet using standard drawing principles.
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Aim:
To study the AUTOCAD Software.
12. DIVIDE Places evenly spaced point objects or blocks along the length
or perimeter of an object
13. DONUT Draws filled circles and rings
14. ELLIPSE Creates an ellipse or an elliptical arc
15. ERASE Removes objects from a drawing
16. HATCH Fills a specified boundary with a pattern
17. HATCHEDIT Modifies an existing hatch object
18. EXTEND Extends an object to meet another object
19. INSERT Places a named block or drawing into the current drawing
20. LAYER Manages layers and layer properties
21. LINE Creates straight line segments
22. LINETYPE Creates, loads, and set line types
23. OFFSET Creates concentric circles, parallel lines, and parallel curves
24. FILLET Rounds and fillets the edges of objects
25. MIRROR Creates a mirror image copy of objects
26. MOVE Displaces objects a specified distance in a specified direction
Creates a slide file of the current view port in model space, or
27. MSLIDE
of all view ports in paper space.
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59. DELAY Provides a timed pause within a script
60. DIM AND DIM Accesses dimensioning mode
61. DIMALIGNED Creates an aligned linear dimension
62. DIMANGULAR Creates an angular dimension
RESULTS:
Thus the AutoCAD software was studied.
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Aim:
To understand drawing standards.
Draw basic sketches using Autocad.
Procedure:
Open Auto CAD; Draw the Shape given in the Fig.
Add relations and Smart dimensions and make sure that the Sketch is Fully
constraint Change the dimensions according to Fig.
Commands used:
Line, Circle, Arc, Fillet, Trim, Smart Dimension, Relations, Show, View
Diagram-1
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Diagr m - 2
Result:
The basic sketches were drawn using Auto as shown in Figures and the
required parameters were added to modify the dimensions at later stage if necessary.
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Date:
Commands used:
• Rectangle • Line • Copy • Move • Hatch • Text • Dim linear • Trim • Offset
Result:
Thus the bush bearing has been drafted by using standard software.
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Prof.J.Bharani Chandar Prof. S.Muthukumarasamy Prof.S.K.Nagoor vali
Date:
Result:
Thus the Plummer Block has been drafted by using standard software.
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Prof.J.Bharani Chandar Prof. S.Muthukumarasamy Prof.S.K.Nagoor vali
Date:
Commands used:
• Rectangle • Line • Copy • Move • Hatch • Text • Dim linear • Trim • Offset
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Result:
Thus the Safety Valve has been drafted by using standard software.
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Prof.J.Bharani Chandar Prof. S.Muthukumarasamy Prof.S.K.Nagoor vali
Ex. No. 12 2D Drafting of Non Return Valves
Date:
Commands used:
• Rectangle • Line • Copy • Move • Hatch • Text • Dim linear • Trim • Offset
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Result:
Thus the Non-Return valve has been drafted by using standard software.
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Ex. No. 13 Study of Solid Works
Date:
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Fig 3: Solid works Startup Dialog Box
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Part
The Part button is chosen by default in the New Solid Works Document dialog box. Choose the
OK button to start a new part document to create solid models or sheet metal components. When you
start a new part document, you will enter the Part mode
Assembly
Choose the Assembly button and then the OK button from the New Solid Works Document dialog box
to start a new assembly document. In an assembly document, you can assemble the components created in
the part documents. You can also create components in the assembly document.
Drawing
Choose the Drawing button and then the OK button from the New Solid Works Document dialog box to
start a new drawing document. In a drawing document, you can generate or create the drawing views of
the parts created in the part documents or the assemblies created in the assembly documents.
Whenever you start a new part document, by default you are in the part modeling environment. But, you
need to start the design by first creating the sketch of the base feature in the sketching environment. You
can invoke the sketching environment using the Sketch tool available in the Standard toolbar.
You can also choose the Sketch button from the Command Manager (Figure 4) to invoke the
Sketch Command Manager.
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