Chapter 1Chapter 1

Engineering Graphics as a

Language

EngineeringDrawing and Design

EngineeringDrawing and Design

The Need For Engineering Drawings

People have expressed their thoughts and concepts for many centuries by the use of drawings. Some of those drawings are pure art.

In engineering and technology technical drawings are widely used. Whether it is an aircraft engine or a child’s wagon, the persons responsible for making it need accurate and definitive information on all parts and on how they fit together.

Drawings can be 3-dimensional, or 2-dimensional.

The drawing can be done by computer or by hand.

There are many types of engineering drawings and each has its own value and use.

Typical Branches ofEngineering Drawings

Mechanical

ManufacturingPower GenerationTransportationPower ServicesAtomic EnergyMarine Vessels

Typical Branches ofEngineering Drawings

Architectural

Commercial BuildingsResidential BuildingsInstitutional BuildingsEnvironmental Space Forms

Typical Branches ofEngineering Drawings

Electrical

Power GenerationPower ApplicationTransportationIlluminationIndustrial ElectronicsCommunicationsInstrumentationMilitary Electronics

Typical Branches ofEngineering Drawings

Aerospace

AerodynamicsStructural DesignInstrumentationPropulsion SystemsMaterialsReliability TestingProduction Methods

Typical Branches ofEngineering Drawings

Piping

Liquid TransportationManufacturingPower ServicesHydraulicsPneumatics

Typical Branches ofEngineering Drawings

Structural

Structural DesignsBuildingsAutomobiles PlanesShipsBridges

Typical Branches ofEngineering Drawings

Technical Illustration

New ProductsAssembly InstructionsPresentationsCommunity ProjectsRenewal Programs

Our object is to study the language of engineering graphics so that we can write it clearly for those familier with it and read it readily when written by an other.

To do this, we must know the basic theory and be familiar with its accepted conventions and abbreviations.

Since its principles are essentially the same throughout the world, a person who has been trained in the practices of one nation can readily adapt to practices of another.

Engineering Graphics as a Language

Methods of Expressions

The drawing can be done by computer or by hand.

Drafting Equipment

Drafting Machine

Drafting Equipment

Triangles

45°

30°/60°

Drafting Equipment

Protractors

Half-Circle

Full-Circle

METRIC SCALE

1:1 SCALE (1mm DIVISIONS)

mm1:1

0 10 20 30 40 50 60 70 80

18 34 52.5

Drafting Equipment

Compasses

Drop Bow

Bow

Drafting Equipment

Templates

Drafting Equipment

Irregular Curves

Drafting Equipment

Pencil

Eraser

Technical Pens

CAD

Computer Aided Drafting

FasterPreciseComplicated shapesSolid modellingCAM (CNC)

CATIA