Introduction of Engineering Graphics

33
Subject : Engineering Graphics Branch : Mechanical Class : B2 Semester : 2 nd Year : 2014 Topic : Introduction Group members Enrollment no Prajapati Ashvinkumar 130980119079 Prajapati Hardik 130980119080 Prajapati Jay 130980119081 Prajapati Kaushik 130980119082

description

The Introduction of Engineering Graphics...

Transcript of Introduction of Engineering Graphics

Page 1: Introduction of Engineering Graphics

Subject:

Engineering Graphics

Branch: MechanicalClass: B2Semester: 2nd

Year: 2014Topic: Introduction

Group members Enrollment no

Prajapati Ashvinkumar 130980119079

Prajapati Hardik 130980119080

Prajapati Jay 130980119081

Prajapati Kaushik 130980119082

Page 2: Introduction of Engineering Graphics

Introduction

Engineering means “Applied science” Graphics means “drawings” “Language of Engineers” It is a way for communicating Engineer’s ideas, designs and

thoughts to others. The communication of ideas through the graphical language. It’s helps to reduce the time, increase the accuracy of the

object to be manufacture.

Page 3: Introduction of Engineering Graphics

Freehand drawing

The lines are sketched without using instruments other

than pencils and erasers.

Example

Page 4: Introduction of Engineering Graphics

Instrument drawing

Instruments are used to draw straight lines, circles, and

curves concisely and accurately. Thus, the drawings are usually

made to scale.

Example

Page 5: Introduction of Engineering Graphics

ISO International Standards Organization

Standard Code

ANSI American National Standard InstituteUSA

JIS Japanese Industrial StandardJapan

BS British StandardUK

AS Australian StandardAustralia

Deutsches Institut für NormungDINGermany

Country Code Full name

India BIS Bureau of Indian Standards

Page 6: Introduction of Engineering Graphics

Drawing Sheet

Trimmed paper ofa size A0 ~ A4.

Standard sheet size (JIS)

A4 210 x 297

A3 297 x 420

A2 420 x 594

A1 594 x 841

A0 841 x 1189

A4

A3

A2

A1

A0(Dimensions in millimeters)

Page 7: Introduction of Engineering Graphics

Drawing Scales

Scale is the ratio of the linear dimension of an element of an

object shown in the drawing to the real linear dimension of the

same element of the object.

Size in drawing Actual size

Length, size

:

Page 8: Introduction of Engineering Graphics

Drawing Scales

Designation of a scale consists of the word “SCALE”

followed by the indication of its ratio, as follow

SCALE 1:1 for full size

SCALE X:1 for enlargement scales (X > 1)

SCALE 1:X for reduction scales (X > 1)

Dimension numbers shown in the drawing are correspond

to “true size” of the object and they are independent of

the scale used in creating that drawing.

Page 9: Introduction of Engineering Graphics

Visible lines represent features that can be seen in the

current view

Meaning of Lines

Hidden lines represent features that can not be seen in

the current view

Center line represents symmetry, path of motion, centers

of circles, axis of axisymmetrical parts

Dimension and Extension lines indicate the sizes and

location of features on a drawing

Page 10: Introduction of Engineering Graphics

Example : Line conventions in engineering drawing

Page 11: Introduction of Engineering Graphics

Text on Drawings

Text on engineering drawing is used :

To communicate nongraphic information.

As a substitute for graphic information, in those instance where text can communicate the needed information more clearly and quickly.

Uniformity - size- line thickness

Legibility - shape- space between letters and words

Thus, it must be written with

Page 12: Introduction of Engineering Graphics

DIMENSIONING METHOD

Aligned Dimensioning Unidirectional Dimensioning

Page 13: Introduction of Engineering Graphics

Objectives in Drawing

Typical Drawing Equipment

Objectives in Drawing

1. Accuracy

2. Speed

3. Legibility

4. Neatness

Page 14: Introduction of Engineering Graphics

Drawing board

It’s a rectangular wooden board 22 mm of thick and size is 650*470 mm

Page 15: Introduction of Engineering Graphics

Drawing board must be placed on the table with working edge always to be at the left side.

Working edge

Page 16: Introduction of Engineering Graphics

Mini drafter

It’s a combined form of T-square ,Set square Protractors and scale. One end of the drafter is Clamped at the left top end.

Page 17: Introduction of Engineering Graphics

Drawing Pencils

High-quality drawing pencils should be used in technical drawing, never ordinary writing pencils.

HB(soft grade) – used for lettering, freehand sketching

H ( medium grade ) - used for visible outlines, edges

2H(hard grade) - used for dimension line, hidden line

Page 18: Introduction of Engineering Graphics

Drawing sheets

The basic principle involved in arriving at the sheet size is x1:x2 = 1:√2

X1,X2 are sides of the sheet

The surface area of A0 size sheet is one square meter.

Page 19: Introduction of Engineering Graphics

T-square

Page 20: Introduction of Engineering Graphics

Some drawing instruments

Page 21: Introduction of Engineering Graphics

Layout of drawing sheets

Standard form of arrangement

Important particulars are included

Facilitate quick reading of important particulars – quick references are located easily – drawings are prepared at various locations and shared

Page 22: Introduction of Engineering Graphics

Borders

space left all around in between the trimmed edges of the sheet a minimum of 10 mm

Page 23: Introduction of Engineering Graphics

Line types

Page 24: Introduction of Engineering Graphics

Engineering scales

Dimensions of large objects must be reduced to accommodate

on standard size drawing sheet.

This reduction creates a scale of that reduction ratio.

This ratio is called reducing scale

Full scale 1:1

Reducing scale 1:2,1:5,1:10

Enlarging scale 2:1,5:1,10:1

Page 25: Introduction of Engineering Graphics

Geometric construction

Point : A point is not a thing, but a place. We indicate the

position.

Line joining of two point but no breath and think

Polygon :it’s a plane figure more than 4 straight lines

Depending on the number of sides the regular polygon are

classified as

1) Rectangle, 2) Pentagon, 3) Hexagon, 4) Heptagon,

5) Octagon, 6) Nonagon.

3-1024 sides is name as polygon.

Page 26: Introduction of Engineering Graphics

Vertical plane –when the observer is viewing it from the

front.

It shows only two dimension length and height.

Horizontal plane – when the observer is viewing it from top.

It shows only breath.

Page 27: Introduction of Engineering Graphics

Vertical & horizontal plane

Page 28: Introduction of Engineering Graphics

Orthographic projection

Page 29: Introduction of Engineering Graphics

Four quadrant

Page 30: Introduction of Engineering Graphics

First angle projection

It’s in first quadrant. Top view comes below to the front view

Page 31: Introduction of Engineering Graphics

Third angle projection

It’s in third quadrant Top view comes above the front view

Page 32: Introduction of Engineering Graphics

ENGINEERING CURVES

Page 33: Introduction of Engineering Graphics