Technical English - I

4th week

ENGINEERING DRAWING

drawing / plan / graphic / picture / draft / outline / sketch / schema / diagram

What is engineering drawing?What is engineering drawing?It is the art of representation of geometrical It is the art of representation of geometrical

objects on a drawing sheet. An engineering objects on a drawing sheet. An engineering

drawing is used to fully and clearly define drawing is used to fully and clearly define

requirements for engineered items. It is a requirements for engineered items. It is a

separate language for communicating separate language for communicating

between designer, manufacturer and between designer, manufacturer and

inspection. It is prepared, based on certain inspection. It is prepared, based on certain

principles, symbolic representations, principles, symbolic representations,

standard convention and notation, etc.standard convention and notation, etc.

Importance of engineering drawingsImportance of engineering drawingsEngineering drawing is a two dimensional representation of a threeEngineering drawing is a two dimensional representation of a three--dimensional dimensional

object. It is the graphic language and called the universal language of engineers. object. It is the graphic language and called the universal language of engineers.

As an engineering drawing display a precise picture of the object to be produced. As an engineering drawing display a precise picture of the object to be produced.

It conveys the same picture and information to every trained eye. It conveys the same picture and information to every trained eye.

Types of drawingsTypes of drawings Civil engineering drawingCivil engineering drawing

Civil engineering drawings include:Civil engineering drawings include:

��Architectural plansArchitectural plans

��Structural working drawings (Foundation plan, reinforcement Structural working drawings (Foundation plan, reinforcement

details, utility plans such as water supply and electrification plan etc.)details, utility plans such as water supply and electrification plan etc.)

��Completion drawings (As built drawings) (Drawings showing the Completion drawings (As built drawings) (Drawings showing the

actually constructed feature)actually constructed feature)

architectural plan / foundation plan / reinforcement / utility plan/ as built plan

side view / isometric plan / plan / section / detail

Civil EngineeringCivil Engineering

�� PlansPlans

�� Cross SectionsCross Sections

�� DetailsDetails

Mechanical EngineeringMechanical Engineering��Side views (Top, left, right)Side views (Top, left, right)

��Isometric viewsIsometric views

Drawing stylesDrawing styles�� Manual drawing (Conventional hand drawing)Manual drawing (Conventional hand drawing)

�� CAD (Computed Aided Drafting)CAD (Computed Aided Drafting)

manual drawing / conventional / cad / computer aided drafting

“I HAVEN’T MUCH “I HAVEN’T MUCH

EXPERIENCE OF SUCH EXPERIENCE OF SUCH

AN EARLY VERSION AN EARLY VERSION

OF AUTOCAD”OF AUTOCAD”

Advantages Advantages

Manual methodManual method

� Low purchase cost of equipment

� No need any electronic equipments

� Drawings can be seen straight away any shapes, sizes and angles.

Computer aided methodComputer aided method

� All drawing tools are electronic; Designs can be made quickly and consistently

� Absolute accuracy can be maintained, and mistakes can be minimized

� The computer keeps a record of all dimensions in the drawing

� Changes to drawing can be made easily (Editing processes include the ability to copy,

move, rotate, mirror and erase drawing parts)

� Drawing storage is on a hard drive, memory stick, CD, DVD or floppy disk rather than in a

drawing folio; Minimizes storage space

� Exact copies of drawings can be produced quickly; Hard copies can be produced in color

and to a high professional standard

� The drawings can be reproduced as often and as quickly as you want

� Improves the productivity, efficiency and accuracy of drawings

� Objects can be viewed in 3D and as animation (visualization capabilities)

� Automatic drawing (Drawing via a programming language)

purchase / straight away / consistently / absolute accuracy / hard copy / reproduce / productivity / efficiency / animation / visualization / programming language

DisadvantagesDisadvantages

Manual methodManual method

� For large drawings you need a great deal of space to set it out

� Doesn't link to Computer Numeric Controlled (CNC) devices.

� The time that it takes to reproduce / redraw the drawing in comparison to a

CAD drawing.

� Storage facilities required to keep manual drawings is far greater than CAD

drawings.

Computer aided method Computer aided method

� There are still some shapes that are difficult to draw using CAD software.

� Preferably the computer equipment should be in a climate controlled, dust-

proof environment.

� The cost of purchasing and replacement cost of the equipment is expensive

compared to equipment used to draw manually.

disadvantage / great deal of space / device / redraw / storage facility climate controlled / dust proof environment / replacement cost

drawing board / sheet / instrument / protractor / scale / eraser / emery paper / mylar

List of drawing instrumentsList of drawing instruments

These drawings dawn by These drawings dawn by

hand are taken from the hand are taken from the

project plans of the waste project plans of the waste

water treatment plants of water treatment plants of

the coastal cities in the coastal cities in

Aegean sea; Drawn in Aegean sea; Drawn in

19198080..

CPU / RAM / high-specification / processing / high-resolution / storage / screen

CAD System RequirementsCAD System Requirements

�� CPU Central Processing UnitCPU Central Processing Unit

�� OS Operation SystemOS Operation System

�� RAM Random Access MemoryRAM Random Access Memory

�� Monitor Resolution / Video CardMonitor Resolution / Video Card

�� CAD SoftwareCAD Software

CAD requires a highCAD requires a high--specification computer with a lot of specification computer with a lot of

processing power, storage and highprocessing power, storage and high--resolution screen.resolution screen.

CAD Software

� AutoCAD

� MicroStation

� ArchiCAD

� NX

� ProEngineer

� BricsCAD (IntelliCAD)

� BRL-STR

� Caddie

� CATIA

� GStariCAD

� CADKey

� ProgeCAD

� QCAD

� Shark CAD

� Solid edge

� Solidworks

StandardsStandardsEngineering drawings, being one of the many forms of technical Engineering drawings, being one of the many forms of technical

communication, have to fulfill some accepted standards. There are various communication, have to fulfill some accepted standards. There are various

national, multinational and international standards, but the current trend in national, multinational and international standards, but the current trend in

most countries is to adhere (adopt) the ISO (The International Organization most countries is to adhere (adopt) the ISO (The International Organization

for Standardization) standards.for Standardization) standards.

�� Paper SizesPaper Sizes

�� Drawing sheet layoutDrawing sheet layout

�� Title blockTitle block

�� ScaleScale

�� Line stylesLine styles

�� Dimensioning Dimensioning

�� Text stylesText styles

�� SymbolsSymbols

�� Printing and plotting standardsPrinting and plotting standards

�� Archive libraryArchive library

fundamentals / iso standards / current trend / drawing sheet layout / template

Note that some companies have Note that some companies have

their own drawing template, their own drawing template,

which inserts draftingwhich inserts drafting standard standard

automatically into into the new automatically into into the new

drawing.drawing.

�� Paper SizesPaper Sizes

�� Sheet layoutSheet layout

Drawing sheet layoutDrawing sheet layout

paper size / drawing sheet layout / title block / margin / border line

Paper sizesPaper sizes

scale / reducing scale / enlargin scale / representative factor

�� ScaleScale

�� Title blockTitle block

?!...?!...

Object size Object size

Paper sizePaper size

projection / format / remarks / reduction / enlargement

An example for the drawing title:An example for the drawing title:

�� Title blockTitle block

�� ScaleScale

An example for a custom drawing sheet title blockAn example for a custom drawing sheet title block

object line / hidden line / centerline / extension line / dimension line / break line

�� Line stylesLine styles

Dimension lineDimension line

CenterlineCenterline

Extension lineExtension line

Leader lineLeader line

Hidden lineHidden line

Object lineObject line

Dimension lineDimension line

Line stylesLine styles

Break lineBreak line

Contour linesContour lines

object line / hidden line / centerline / extension line / dimension line / break line

�� Line stylesLine styles

Dimension lineDimension line

CenterlineCenterline

Extension lineExtension line

Leader lineLeader line

Hidden lineHidden line

Object lineObject line

Dimension lineDimension line

Line stylesLine styles

Break lineBreak line

Contour linesContour lines

cutting plane / sectional view / hatching line

�� Line stylesLine styles

�� Hatching stylesHatching styles

Hatching stylesHatching styles

glassmetalsandceramicgravelplywoodmarbleconcretestonewoodzincslateironsteelstuccotile

�� SymbolsSymbols

�� Archive libraryArchive library

line properties / line type & color & width & layer / level

Line propertiesLine properties

�� Type (solid, continuous, dash, center, Type (solid, continuous, dash, center,

dotted, dashdotted, dash--dot, custom, etc)dot, custom, etc)

�� Color (black, red, blue, gray, etc or Color (black, red, blue, gray, etc or

codes such as 0, 0.5, 1, 2 etc)codes such as 0, 0.5, 1, 2 etc)

�� Width/thickness (Light, medium, Width/thickness (Light, medium,

heavy or codes such as 0, 0.5, 1, 2 etc)heavy or codes such as 0, 0.5, 1, 2 etc)

�� Layer/level (specific names or codes Layer/level (specific names or codes

such as “Plan”, “Section”, “Roads” etc)such as “Plan”, “Section”, “Roads” etc)

By organizing drawings into levels, By organizing drawings into levels,

it can more easily control which it can more easily control which

areas of the drawing are visible at areas of the drawing are visible at

any time.any time.

Cell or block library / terminator pattern / weld symbols

�� SymbolsSymbols

�� Archive libraryArchive library

North arrow cellNorth arrow cell

Prepared engineering symbolsPrepared engineering symbols

dimension / linear / aligned / ordinate / radius / diameter / angular / baseline

��Dimensioning Dimensioning

�� Text stylesText styles

Dimension stylesDimension styles

�� Dimensioning Dimensioning

�� Text stylesText styles

dimension / linear / aligned / ordinate / radius / diameter / angular / baseline

2D (two dimensional) & 3D (three dimensional) drawings / length / height / depth

3D Drawing3D Drawing2D Drawing (False 3D view)2D Drawing (False 3D view)

Both 2D and 3D have their own unique benefits. “2D” is display as two Both 2D and 3D have their own unique benefits. “2D” is display as two

dimensional geometry which is expressed in length & height on flat dimensional geometry which is expressed in length & height on flat

planes but have no depth. In a 3D drawing file, objects have (planes but have no depth. In a 3D drawing file, objects have (x,y,zx,y,z) )

coordinates while objects in 2D file have only (coordinates while objects in 2D file have only (x,yx,y) coordinates. ) coordinates.

LengthLength

Height Height

LengthLength

Height Height

DepthDepth

CAD Software vendors offers comprehensive CAD Software vendors offers comprehensive project solutions project solutions

beyond a standard CAD package.beyond a standard CAD package.

MicroStationMicroStation--based based

platformplatform products products

AutoCADAutoCAD--based based

platformplatform products products

Thank you…Thank you…

What are the most common “What are the most common “commandscommands” used in CAD? ” used in CAD?

(Please ask people who are using any CAD software. Make (Please ask people who are using any CAD software. Make

a list by selecting top 10 favorite ones.)a list by selecting top 10 favorite ones.)