Mechanical Technical Review

InstructorEng. Mohamed Fathy

Jan. 2015

Contents.Contents.1- Introduction to Special tools in Mechanical Maintenance.2- Lifting Tools & Lifting Equipment.3- Stationary & Rotating Equipment .4- Dry Gas Seals Systems.5- Shaft Alignment 6-Coupling.7- Diesel & Gas Engines.8- Valves.9- Mobile Units.10- Sewage Systems.11- Portable & Utility Water Systems.12- Gears & Gear Boxes13- Power Transmission.14-Bearings, Fans & Blowers15- HVAC.

 

Introduction.Introduction.A workshop is where you can carry out the works by using tools and

machines It can be a dangerous place, so you must learn to use all tools in the

workshop.

You will learn to use many tools and machines in the workshop. Always ask

for your teacher’s advice before using a machine for the first time.

You must listen to the teacher when he tells you how to use them

Mechanical Tools Types

1- Hand Tools.

2- Power Tools.

3- Cutting Tools.

4- Measuring Tools.

Spanners/ WrenchesThe two words “spanner” (in British English)

and “wrench” (in American English) refer to the same tool.

Spanners/Wrenches are different in shape to provide ease of operation under certain conditions.

They are manufactured from high tensile or alloy steel.

1- Hand Tools

The sizes of metric spanners are identified by the distance across flats of a nut or bolt head

S=24 mm

Box spanners Box spanners

box-end wrenches are recommended to be used when a better grip is needed and when the spanner swing is restricted.

Combination spanners Combination spanners

This type comes with an open end from one side and a ring end from the other side .

Usually both ends are having the same size

hammering spannershammering spanners

Adjustable spanners Adjustable spanners

Adjustable spanners are spanners that have a moving jaw to fit different bolt/nut sizes

Chain WrenchChain Wrench

Reversible RatchetReversible RatchetReverse rotation of socket turning

Torque WrenchTorque WrenchMeasure amount of torque

Adjustable

1- Use the 1- Use the correct size correct size spanner for the job.spanner for the job.2- 2- Pull towards the body Pull towards the body whenever possible.whenever possible.3- Do not obtain 3- Do not obtain extra leverage extra leverage by using pieces of by using pieces of pipepipe. . 5- Do not 5- Do not hit a spanner hit a spanner with a hammer.with a hammer.6- Make 6- Make suresure your your handshands will will not strike not strike any any obstructions.obstructions.

The following Recommendations should be considered:

Wheel PullerWheel PullerRemove wheel from axle

Great variety of screwdrivers Great variety of screwdrivers typestypes and and sizessizes available. available.

Screwdrivers

Always use the correct size screwdriver for the screw head; the blade should fit the width of the screw head.

- pliers available as many - pliers available as many differentdifferent typestypes and and sizessizes- used for - used for holdingholding and and cuttingcutting- usually forged from - usually forged from hardened steel hardened steel and then and then machinedmachined

Pliers

Circlip pliersCirclip pliers Circlips are retaining devices They are fitted inside a groove on bores and shafts.

HammersHammersBall peen Hammer

Rubber mallet

Dead blow HammerSledge Hammer

Drill

Used for boring holes.

Safety:Wear glasses, switch off while changing

bits, clamp the job firmly.

2- Power Tools

24

Drill bitsDrill bitsDrill bits are available in clockwise and

counter clockwise rotation for different applications◦boring holes, bolt extraction

Other types may have specific applications for cutting different materials◦metal, plastic, wood

Grinder/Cutter

Used for grinding/cutting

Safety??Wear glasses while using.Check for the protection cover.Switch off the machine while changing

blades.

Miter BoxMiter BoxCutting angles

Portable Circular SawPortable Circular SawSawing wood in construction projects

Portable Jig SawPortable Jig SawMaking irregular cuts

Grease GunGrease GunLubricating through grease fittings

3- Cutting Tools

Used for Used for cuttingcutting the the metalsmetals, , woodwood and and non-metallicnon-metallic materials materials

HackSawHackSaw

Punch & ChiselPunch & Chisel

•Wear safety glasses.

Wood ChiselWood Chiselshaping wood

PVC CutterPVC CutterCutting non-metallic pipe

Tube CutterTube CutterCutting soft tubing

- Methods of collecting data - Methods of collecting data depend on what is being depend on what is being measuredmeasured- Check for excessive wear or - Check for excessive wear or damage when servicing damage when servicing components components

4- Measuring Tools

.LINEAR EQUIVALENCE

Conversion FactorsEnglish to Metric1 inch =1 foot =5,280 feet = 1 mile =

 2.54 centimeters (= 0.254m)0.3048 meters (= 304.8mm)1.34 kilometers

Metric to English1 centimeter =1 meter =1 kilometer =

 0.3937 inches3.280 feet (= 39.37 inches)0.746 miles (= 3,280.84 feet)

4- Measuring Tools

Ruler/Tape MeasureRuler/Tape MeasureStraight or curved measuring

Feeler Gauge used for Feeler Gauge used for Valve lash Measure spark plug gap

MicrometersMicrometersVery accurateEasy to use after you learn how

Micrometer Caliper ExampleDetermine the reading for the micrometer caliper

in the illustration.

1. Tenths of an inch 0.3002. Twenty five thousands ( 0.025 x 2 ) 0.0503. Thousands 0.015 Sum (measurement) 0.365

Vernier CalipersVernier Calipers

Picture from pg 42

Dial CaliperDial Caliper

Other Measuring ToolsOther Measuring Tools

Height GaugesThread Gauges

2- Lifting Component2- Lifting Component

Hooks•Manufacturers’ identification.

• Never weld on hooks.

• Working safety latch.

Hooks Types

Hooks Load & Inspection

Eye Bolts

Shackles

Recommended Not Recommended Recommended

www.prothermindia.com

Proper Use of Shackles

Never replace a shackle pin with a bolt

The load will bend the bolt

www.prothermindia.com

Avoid eccentric loads

Bad Good www.prothermindia.com

Types of SlingsTypes of Slings

1) Wire Rope Slings

2) Chain Slings

3) Synthetic Web Slings

4) Fiber rope

www.prothermindia.com

Ropes, chains, and slingsRopes, chains, and slings

• Primary hazard is structural failure due to:– Overloading (over SWLSWL)– Deterioration and/or wear– Environmental exposure

www.prothermindia.com

Other sling components include rigging hardware attachments such as clips, hooks, eyebolts, shackles, sockets, wedge sockets, triangle choker fittings, and master links.

Wire Rope and Wire Rope SlingsWire Rope and Wire Rope Slings

Components of Wire Ropewww.prothermindia.com

Installing Wire Rope Clips

Installed properly as to number, direction, spacing and torque.

www.prothermindia.com

HITCHES

A load lifted outside its center of gravity will shift to create excess side stress on one sling.

How Horizontal Angle Affects Sling Capacity

Note: A good operating practice is to keep sling angles from going below 60 degrees

www.prothermindia.com

Operating Engineers National Hazmat Program

Mechanical spliceMechanical splice

Hand Signals

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Sheave grooves may become grooved if cable’s Sheave grooves may become grooved if cable’s nominal diameter is reduced, indicating wear.nominal diameter is reduced, indicating wear.

www.prothermindia.com

www.prothermindia.com

ReviewReview

Select the right sling for the job.Inspect slings prior to use,

removing from service any in question.

Properly store slings when finished to avoid damage.

www.prothermindia.com

Kinking, core protrusion, and bird caging may be encountered when inspecting a wire rope.

InspectionInspection

Fiber rope inspection is made to remove a rope from service before the rope’s condition poses a hazard with continued operation.

Webbing should be inspected at least annually and round slings should be inspected monthly.

Chain should be inspected annually.

3- Stationary & Rotating Equipment

Rotating Equipment Mechanical Pumping Equipment

Introduction

WHAT IS THE PUMP?

Pumps are machines which supply energy to a liquid in order to move it from place to another.

IntroductionPumps enable a liquid to:

1. Flow from a region or low pressure to one of high pressure.

2. Flow from a low level to a higher level.

3. Flow at a faster rate.

There are two main categories of pump:

Diaphragm

Piston

Plunger

Reciprocating Rotary

Mixed flow Gear

Lobe

Sliding Vane

Screw

Axial flow

Centrifugal

Rotodynamic

Turbine

Positive displacement

PUMP

2

•Rotodynamic Pumps•Positive displacement pumps.

A kinetic pump imparts velocity energy to the fluid, which is converted to pressure energy upon exiting the pump casing

A positive displacement pump moves a fixed volume of fluid within the pump casing by applying a force to moveable boundaries containing the fluid volume. 

4

What is the main difference between kinetic and positive displacement pumps ?

Difference between type of pumps

Parameter Centrifugal Pumps Reciprocating Pumps Rotary Pumps 

Optimum Flow and Pressure Applications

Medium/High Capacity,Low/Medium Pressure

Low Capacity,High Pressure

Low/Medium Capacity,Low/Medium Pressure

Maximum Flow Rate 100,000+ GPM 10,000+ GPM 10,000+ GPM

Low Flow Rate Capability No Yes Yes

Maximum Pressure 6,000+ PSI 100,000+ PSI 4,000+ PSI

Requires Relief Valve No Yes Yes

Smooth or Pulsating Flow Smooth Pulsating Smooth

Variable or Constant Flow Variable Constant Constant

Self-priming No Yes Yes

Space Considerations Requires Less Space Requires More Space Requires Less Space

Costs Lower InitialLower Maintenance

Higher Power

Higher InitialHigher Maintenance

Lower Power

Lower InitialLower Maintenance

Lower Power

Fluid Handling Suitable for a wide range including clean, clear, non-

abrasive fluids to fluids with abrasive, high-solid content.

 Not suitable for high viscosity

fluids  

Lower tolerance for entrained gases

 

Suitable for clean, clear, non-abrasive fluids.  Specially-fitted pumps suitable for abrasive-slurry service.

 Suitable for high viscosity

fluids  

Higher tolerance for entrained gases

Requires clean, clear, non-abrasive fluid due to close

tolerances   

Optimum performance with high viscosity fluids

 Higher tolerance for

entrained gases

Type of Centrifugal Pumps

Single SuctionDouble SuctionFlow type (radial, Mixed and Axial)Single Stage & Multi stageMulti Stage

Construction of Centrifugal Pumps

6

1- Casing:-Casing generally are two types:

I. Volute casings for a higher head.

A volute is a curved funnel increasing in area to the discharge port and convert velocity energy to pressure

energy.

2.Split casings .

2-ImpellerThree main categories of centrifugal pumps exist

Radial flow Mixed flow

Axial flow

Pump Carves

8

H-Q CurveBrake Power CurveEfficiency CurveNPSH Curve

Net Positive Suction Head Net Positive Suction Head (NPSH)• That means the level of liquid can the pump workWhat will happen if the pump work out of NPSH characteristic?

When the pressure falls below the vapour pressure of the liquid at a given temperature, boiling occurs and small bubbles of vapour are formed. These bubbles will grow in the low-pressure area and implode when they are transported to an area of pressure above vapour pressure. The term given to this local vaporization of the fluid is Cavitations.

If NPSHA is less than NPSHR the Cavitations is occur

This Cavitation effect on the pump can cause damage on the casing and impeller.

Centrifugal pumps - shaft sealingCentrifugal pumps - shaft sealing

To connect the motor to the impeller, the shaft has to pass through an aperture in the casing.

To allow the shaft to rotate freely in the casing aperture there needs to be a gap, but this gap needs to be closed off to stop air from being drawn in from atmosphere or liquid from leaking out during operation.

There are two common methods. Packing Mechanical seal

PackingPacking

PackingPacking

89

MECHANICAL SEAL

Mechanical sealsMechanical seals

Mechanical sealsMechanical seals

Positive Displacement Pump Types

GEAR PUMPGEAR PUMPfluid is trapped between gear teeth and the housing

TheoryTheory

SCREW PUMPSCREW PUMP The pump forms hollow cavities which contain the fluid and move it along

the screws. One screw is the drive screw and the other screw or screws is/are driven by the drive screw.

SINGLE DIAPHRAM PUMPSINGLE DIAPHRAM PUMP

SuctionSuction DischargeDischarge

Piston TypePiston Type

Vane TypeVane Type

4- DRY GAS SEALS4- DRY GAS SEALS

Spiral groove

Groove

diameterInner diameter

Sealing dam

Rotating ringTungsten carbide

( ( Principle of operationPrinciple of operation))

RO

TAA

TIN

G F

AC

ETU

GET

EN C

AR

BID

E O

R S

ILIC

ON

CA

RB

IDE

STA

TIO

NA

RY

FAC

EC

AR

BO

NGAP

SEAL GAS INSEAL GAS IN

GAS LEAKAGEGAS LEAKAGE

P Port 1

Separation barrier

Port 2 Port 3 Port 4 Port 5

Inner seal

Outer seal

Labyrinths

Filtered process gas inlet

To flare process gas + buffer gas

Supply of buffer gas

VENT

buffer gas to separation barrier

STA

TIO

NA

RY

FAC

EC

AR

BO

N

FC = FO

FS P PPRESSURE FORCESPRING FORCE

FC FOGAS FILM FORCE

P

NORMAL GAP 0.003 mm AT STEADY STATE

FOGAS FILM FORCE

DECREASED GAP

FO >FCEQILIBRIUM RESTORING FORCE

FOGAS FILM FORCE

P

FC > FORESTORING FORCE

INCREASED GAS FILM FORCE

DECREASED

GA

S FILM FO

RC

E

INCREASED GAP

SEGAS SERVICES SEGAS SERVICES Damietta LNG Plant, Egypt.Damietta LNG Plant, Egypt.

Hassen Maky 30/03/2004Hassen Maky 30/03/2004

OPENNING FORCEFFOO

CLOSING FORCEFFCC

5- Shaft Alignment

Misalignment TypesOffset misalignment

Angular misalignment

Different Ways of Aligning ShaftsDifferent Ways of Aligning Shafts

Straight edge Dial Indicator Methods

Laser Systems

Misalignment is corrected at the feetMisalignment is corrected at the feet

6- Couplings6- Couplings

CouplingsCouplingsCoupling is a device used to connect two shafts together at their ends for the purpose of transmitting power

Motor

Coupling

Pump

Types of couplingTypes of coupling Rigid Flexible Universal

Rigid coupling

Flexible coupling

Universal coupling

Rigid couplingRigid couplingFlange

Driven Shaft

Driving Shaft

Key Hub

•Rigid couplings are used when precise shaft alignment is required

•Simple in design and are more rugged

• Generally able to transmit more power than flexible couplings

Flanged Coupling

Chain CouplingAdvantages• Ease of assembly and disassembly• Little number of parts

DisadvantagesSpeed limit due to balancing difficultiesNeed for lubricationLimited allowable axial displacement

Diaphragm CouplingDiaphragm Coupling

• Excellent balance characteristics• No need for lubrication• Low coupling weight and bending forceson shafts• Acceptance of high temperatureenvironment

Elastomeric CouplingElastomeric CouplingAdvantages• Minimal wear in coupling• Vibration damping and isolation• No need for lubrication

Disadvantages• Speed limit due to distortion ofelastomeric medium• Sensitivity to environment condition,(temperature, corrosion, etc...)

Gear CouplingGear CouplingAdvantages•High speeds capability•Good balance characteristics

Disadvantages•Need for lubrication• Temperature limitation

Metallic Grid CouplingMetallic Grid Coupling

Advantages• Torsionally soft•Ease of assembly and disassembly

Disadvantages•Need for lubrication•Temperature limitation•Speed limitation

7- Diesel & Gas Engines7- Diesel & Gas Engines

INTERNAL COMBUSTION ENGINE BASIC COMPONENTSINTERNAL COMBUSTION ENGINE BASIC COMPONENTS

COMBUSTION TAKES PLACE INSIDECOMBUSTION TAKES PLACE INSIDE THE ENGINE THE ENGINE

THE UPPER ENGINE PORTIONTHE UPPER ENGINE PORTION

CYLINDER HEAD AND THE ENGINE BLOCK CYLINDER HEAD AND THE ENGINE BLOCK (CYLINDER BLOCK)(CYLINDER BLOCK)

PISTON HEAD & PISTON RINGSPISTON HEAD & PISTON RINGS1. The piston reciprocates, or moves up and down, inside the cylinder.2. Piston rings fill the gap between the piston and the cylinder wall.3. The piston rings stop the leakage of the combustion products (high pressure) from

escape through the clearance between the piston head and the cylinder wall.

Piston Head Piston Rings

PISTON HEAD & PISTON RINGSPISTON HEAD & PISTON RINGS

Oil ring

Compression rings

Connecting rod

TEMPERATURES INSIDE THE ENGINE TEMPERATURES INSIDE THE ENGINE CYLINDERCYLINDER

ENGINE ENGINE COMPONENTSCOMPONENTS

THE CRANK SHAFT AND THE MAIN BEARINGSTHE CRANK SHAFT AND THE MAIN BEARINGS

CONNECTING RODCONNECTING ROD

THE FOUR STROKE ENGINETHE FOUR STROKE ENGINE

4. Exhaust stroke

3. Combustion stroke

(power stroke)2. Compression

stroke 1.Suction stroke

(Air intake)

1. SUCTION STROKE1. SUCTION STROKE

In this stroke: 1. The inlet valve is open. 2. The exhaust valve is closed. 3. The piston move from TDC to

BDC. Air fuel mixture enter the cylinder.

2. COMPRESSION STROKE2. COMPRESSION STROKE

In this stroke: 1. The inlet valve is closed. 2. The exhaust valve is closed also. 3. The piston move from BDC to

TDC. Air fuel mixture is compressed in the top portion of the cylinder.

3. THE POWER STROKE3. THE POWER STROKE

In this stroke: 1. The inlet valve is closed 2. The exhaust valve is closed also. 3. The air fuel mixture is burned.

This combustion produces huge amount of gases which act on the piston head pushing it to move from TDC to BDC.

4. THE EXHAUST STROKE4. THE EXHAUST STROKE

In this stroke: 1. The inlet valve is closed. 2. The exhaust valve is open. 3. The piston moves from

BDC to TDC, it push out all combustion products.

FIRING SYSTEM IN MULTI-CYLINDER ENGINEFIRING SYSTEM IN MULTI-CYLINDER ENGINE

DIESEL ENGINE COMPONENTS (IN DETAILS)DIESEL ENGINE COMPONENTS (IN DETAILS)

TURBOCHARGER TURBOCHARGER

The working principle of a turbocharger

HOW TURBOCHARGERS WORKHOW TURBOCHARGERS WORK ? ?

HOW TURBOCHARGERS WORKHOW TURBOCHARGERS WORK

Turbine

Centrifugal compressor

TYPICAL DIESEL TURBOCHARGED ENGINE TYPICAL DIESEL TURBOCHARGED ENGINE SYSTEMSYSTEM

8- VALVES

- WHY WE USE VALVES ?

Purpose Of ValvesPurpose Of ValvesValves are Valves are usedused to to controlcontrol the the flowflow a a

fluidfluid or or gasgas in a plant system. in a plant system. ON-OFFON-OFF

RegulateRegulate

Ball ValveBall Valve

Most ball valves are quick acting - only require 90o turn to completely open or shut valve

Gate ValveGate Valve

Most Gate valves are slow acting - only require sliding to completely open or shut valve

Globe ValveGlobe Valve•Valve operated in the partially open position (throttled) regulated.

Check ValveCheck Valve•Valve operated Backflow prevented (Non Return valve)

•Check valves allow the fluid to flow in one direction only.

9- Mobile Units9- Mobile Units

Machinery, Equipment, and Tools shall not be used beyond the design capacity intended by the

manufacturer where such use may create a Hazard to persons.

Warnings Prior to Starting or Warnings Prior to Starting or Moving EquipmentMoving Equipment

Before starting crushers or moving self-propelled mobile equipment, equipment operators shall sound a warning that is audible above the surrounding noise

level or use other effective means to warn all persons who could be exposed to a hazard from the equipment.

Safety defects; examination, Safety defects; examination, correction and recordscorrection and records

(a) Self-propelled mobile equipment to be used during a shift shall be inspected by the equipment operator before being placed in operation on that shift.

(b) Defects on any equipment, machinery, and tools that affect safety shall be corrected in a timely manner to prevent the creation of a hazard to persons.

Safety defects; examination, Safety defects; examination, correction and recordscorrection and records

(c) When defects make continued operation hazardous to persons, the defective items including self-propelled mobile equipment shall be taken out of service and placed in a designated area posted for that purpose, or a tag or other effective method of marking the defective items shall be used to prohibit further use until the defects are corrected.

Defective stairways, platforms, doors and runways

Not working at:Insufficient lighting in any area where

miners work or travel.Any mobile equipment in use which has not been inspected by the operator for

safety defects.

October 14, 2002, a 25-year-old front-end loader operator, with 3 months mining experience was fatally injured at a sand and gravel operation. The victim parked his loader near the toe of a 33 foot high wall and left the operator's cab when material sloughed off the high wall and buried him.

October 21, 2002, a 48-year-old equipment operator with 11 years mining experience was fatally injured at a sand and gravel operation. The victim was operating a front-end loader feeding a power screen plant when he backed one of the wheels over a drop-off. The loader, which was not provided with a ROPS cab. rolled over, crushing the victim.

December 9, 2002, a 47-year-old truck driver with 1 year10 months mining experience was fatally injured at a crushed stone operation. The victim was in the process of removing a 12 foot long section of a walkway attached to a portable inclined conveyor. As he was cutting a metal attachment using an acetylene torch, the section of walkway collapsed on him.

April 24, 2002, a 22-year-old mechanic with five months mining experience was fatally injured at a crushed stone operation. The victim was conducting a performance test on the parking brake. He drove the loader up a 16 percent ramp when it stopped, rolled backwards and struck the edge of a waste pile. The loader rolled on its side and the victim, who was not wearing a seat belt, was thrown out of the cab.

October 12, 2002, a 52-year-old co-owner of a sand and gravel operation was fatally injured. The victim accompanied her husband to the mine to assist in setting up a new weighing facility while he used a front-end loader to fill in dirt around the newly installed truck scales. Apparently the victim inadvertently walked into the path of the loader as it was backing.

February 8, 2000, a 60-year-old mine foreman with 23 years mining experience was fatally injured at a sand and gravel operation. The victim, who was scurrying to move his pick-up truck out of the way, was run over by a scraper as it was backing up.

Do Do NOT operate NOT operate or continue to or continue to operate any operate any equipment ifequipment if::

-The seat belt is defective. -The service brakes can’t stop it on grades.

-Any guards are missing. -The air compressor does not keep up.

-The engine stalls for no reason. -The accelerator or hydraulic controls are not

working. -Visibility decreases - lights quit, windows cracked,

dense fog etc.

10- Sewage Systems10- Sewage Systems

Justification for wastewater treatment

To manage water discharged from homes, businesses, and industries to reduce the threat of water pollution.

Pollution from sewage is a primary environmental health hazard (wastewater effluent).

Wastewater Treatment DiagramWastewater Treatment Diagram

Preliminary Secondary

WW influent

WW effluent

sludge

Primary Tertiary

Disinfectant

Sludge Treatment and Disposal

Wastewater Treatment Wastewater Treatment ProcessesProcesses

Preliminary:Treatment is a physical process that removes large

contaminants.Primary:Treatment involves physical sedimentation of particles.Secondary:Treatment involves physical and biological treatment to

reduce organic materials of wastewater.Tertiary or advanced treatments.Filtration and Carbon Adsorption

Wastewater Treatment StageWastewater Treatment Stage

Preliminary Preliminary TreatmentTreatment

Preliminary StagePreliminary Stage Bar ScreenBar Screen

catches large objects that

have gotten into sewer system such as bricks, bottles, pieces of wood, etc.

Preliminary StagePreliminary Stage Grit Chambers Grit Chambers

Deposition of inorganic materials to tank bottom such as soil particles and sand.

Primary TreatmentPrimary Treatment

Primary treatment reduces the suspended solids and the B.O.D. of the wastewater.

Primary StagePrimary Stage Primary settling tank Primary settling tank

Sludge from the primary sedimentation tanks is pumped to the sludge thickener.

- more settling occurs to concentrate the sludge prior to disposal

Sludge TreatmentSludge Treatment

Secondary Treatment

Secondary TreatmentSecondary treatment is a biological process.Utilizes bacteria and algae to oxidation organic matter in the wastewater.In biological treatment to be used The Trickling filters or aeration tanks.

Secondary Treatment Trickling filters

Used Sand

Secondary Treatment Aeration Tanks

Using Air Compressor

The final clarifiers remove additional sludge and further reduce suspended solids and B.O.D.

Secondary Treatment Final Stage

11- Portable & Utility Water 11- Portable & Utility Water SystemsSystems

Water Treatment

179 May 2, 2023

Drinking water TreatmentDrinking water Treatment

- People want to get drinking water free of bacteria, no color, taste and smell it. natural water does not have these qualities, but rarely.- Potable water source for drinking: rivers, lakes and groundwater

180 May 2, 2023

Drinking water TreatmentDrinking water Treatment

Clarification & Sedimentation Primarily a physical process, but may be aided by addition of

chemicals. Filtration Also primarily physical, but chemicals may aid the process. Disinfection Typically a chemical process that reduces pathogenic

microorganisms.

Water treatment transforms raw surface and groundwater into safe drinking water.

Water treatment involves two major processes: physical removal of solids and chemical disinfection.

Treatment Process

Raw WaterStorage

Mixing clarificationSedimentation

Filtration

Clear Well

Distribution

Ozonation

Surface Water Treatment Plant

Added Chemical to pH Adjustment Disinfectant (Cl2, NaOCl)

182 May 2, 2023

للشرب الصالحة المياه معالجة مراحل

نهــر

مضخة

غربلة تندف وتصفيق

أوحال

ترشيح بالرمل الدقيق

غاز األوزون

التعقيم بغاز األوزون

التعقيم بالكلور(كَلَْورة)

التوزيع على المستهلكين

برج مائي

الترشيح بالفحم النشط

Preliminary StagePreliminary Stage ScreeningScreening

By screen: catches large objects

that have gotten into sewer system such as stones and branches etc.

Preliminary StagePreliminary Stage Sedimentation Sedimentation

By Gravity

WATER

WATER TOWARDS FILTRATION

Coagulated particles fall, by gravity, through water ina settling tank and accumulate at the bottom of thetank, clearing the water of much of the solid debrisand clear water moves to filtration.

Water TreatmentFILTRATION

FILTRATION: The water passes through filters, some made of layers of sand, and charcoal that help remove smaller particles.

DISINFECTION: A small amount of chlorine is added or some other disinfection method is used to kill microorganisms that may be in the water.

STORAGE: Water is placed in a closed tank or reservoir for disinfection to take pace. The water then flows through pipes to home and business

WATER FROM

SEDIMENTATION

Water DisinfectionPurpose of disinfection:

To make Drinking water free of any disease causing bacteria and microbes.

Methods of disinfection:

There are 3 mainly used disinfection methods at large scale.

CHLORINATIONOZONATIONULTRAVIOLET RADIATION

12- GEARS12- GEARS

SPUR GEAR

WORM GEAR BEVEL

GEAR

Types of Gears - continuedTypes of Gears - continued

G - Bevel gearsH - Spiral bevelJ - Crown bevelK - Spiral gearsL - Worm and wheelM - Hypoid gear

Non-parallel or non-intersecting axis gearing

Internal Spur Gear SystemInternal Spur Gear System

13- Power Transmission13- Power Transmission

Input shaft gear turns countershaftgears. Countershaft gears turn

output shaft gears

191

Motion and torque transmission examplesMotion and torque transmission examples

•Right angle crossing shafts•High friction and wear•High speed reduction

•Smooth tooth interaction•Low noise

Rotary-Linear power transmission

14- Bearings, 14- Bearings, Fans & BlowersFans & Blowers

Bearings Fans Blowers

Transmission BearingsTransmission Bearings Bearings reduce the friction between the surfaces of rotating

parts Three basic types are used:

◦ ball bearings◦ roller bearings◦ needle bearings

Used between shafts and housing.

FAN

-High capacity of air

-Low pressure

-Max. ∆p=100mbar

Fans & Blowers

FansFans

Blowers

•High capacity of air

•Medium pressure

•Max.∆p=1000mbar

COMPRESSOR

•Medium capacity of air

•Hight pressure

•Max.∆p= >10bar

15- HVAC Heating, Ventilation, Air-Conditioning

Where?Where?

199

Mechanical Room: Boilers, chillers, pumps, heat exchangers…

Air Handling Units (AHUs): heat, cool, humidify, dehumidify, ventilate, filter and distribute the air.

Room Controls: thermostats and Variable Air Volume (VAV) boxes

In the mechanical roomIn the mechanical room

200

Boiler

Chiller

HeatingHeating

201

CoolingCooling

202

AHU – Air Handling UnitAHU – Air Handling Unit

203

Return air

Exhaust air

Outside air Supply air

204

Damper

Heating/Cooling Coil

Fan

Sensor

Filter

What’s in an AHU?AHU – Air Handling UnitAHU – Air Handling Unit

HumidificationHumidification

205

Why before the cooling coil?

VAVVAV

206

Two variables – Temperature & Air Volumedamper

The box you can see in the hallway.

IF temperature too highFirst reduce reheat till fully closedThen increase air volume

IF temperature too lowFirst reduce air volume till minimumThen start reheat

WinterWinter207

Outside

Return

Mixed

SummerSummer208

Outside

Return

MixedCooled and dehumidified