Introduction to engineering drawing modified

THINK ONCE… IS YOUR DISPOSABLE (PLASTIC) GLASS

CLEANED AFTER ITS MANUFACTURE..??

…..IT CONTAINS ARSENIC DUST..…REALLY A CANCER REAGENT…

…IF ANY HOT…LIQUID POUR IN IT…IT(Arsenic) GET DISSOLVED.

Introduction to Engineering Drawing

Why Drawings are needed?What is an Engineering Drawing?

Is an Universal LanguageStandardized conventions for layout, nomenclature, interpretation, appearanceDeals with PreciseIn technical nature

Introduction to Engineering Drawing

Specification

Initial Design

Evaluate Design

Design Satisfy Specification ?

Modify Design

Data for

Production

Drawing Types

• Types of Engineering Drawings• General Classification

1. Free hand sketch2. Orthographic Projection

a. 1st angle Projectionb. 2nd angle projectionc. 3rd angle Projectiond. 4th angle Projection

3. Pictorial views– Isometric views– Oblique views

4. Perspective views

Drawing Types1. Free hand sketch

Drawing Types1. Orthographic Projection

Orthographic Projection

First AngleFirst Angle

Orthographic Projection

Third AngleThird Angle

Isometric Projection

Oblique Views

Perspective Views

But the realistic view (Naked Eye) is containing not parallel lines but lines appear to be converge & meet at a point.

Perspective Views

Perspective Views

Two Point Perspective

Vanishing point

Manual Drafting

Important points

• Standards Use– ISO 2768, BS 8888, ANCI –Y14– Sri Lanka Standard 409: 1977

• Paper Sizes

Line Types

Sectional Views

Important Points

– Name of the Item– Drawing Number– Drawn, approved and verified by.– Original scale– Date of the drawing– Signatures– Copyrights clause– Projection symbol– Unit of measurement– Drawing practice standard

DimensioningLinear Dimensioning

Angular Dimensioning

CHAIN-PARALLEL DIMENSIONING

Dimensioning Diameters

Dimensioning Holes

ThreadsThreads

YOUR CHEWING GUM CONTAINS …..

Appropriately, the stomach and intestines may become exhausted. So, concerns about stomach burns, ulcers and risks of different cancers arise.

ANIMAL FAT (Intestines)……..