how we build a car

8/9/2019 How we build a car

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How we build a carA publication from Vauxhalls Education Service

Factfile - Edition Number 6, Summer 2001


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In todays competitive motor industry, superb design alone isnot enough to create a state-of-the-art car. A combination oftraditional human skills, new manufacturing techniques, andadvanced product design are key elements in Vauxhalls man-ufacturing philosophy.

Vauxhall builds cars at two assembly plants in Britain.The Luton plant, established in 1905, is some 35 miles northof London. Luton builds the Vectra model for the home mar-ket as well as export.

In 1962, Vauxhall established a new plant at EllesmerePort in Cheshire. The plant manufactures Astra cars and vansfor home and export markets as well as body panels, sub-assemblies for other GM manufacturing plants in Europe.

Quality and environmental issuesIn 1993, BS5750 approval was gained by all VauxhallMotors manufacturing facilities. This achievement hasunderlined the companys commitment to quality. Buildingquality cars that people want to buy is the primary objec-tive.

Vauxhall is committed to reducing the impact of itsmanufacturing facilities on the environment. Significantprogress has been made in waste management and energyconservation.

Vauxhall Motors achieved a world first for the motorindustry by securing the BS 7750 (now ISO 14001)Environmental Management Standard at the Ellesmere PortPlant in 1995. In 1996 the Luton Plant also received theaward. Vauxhall became the first car manufacturer in theUK to register both assembly plants under EMAS, the

European Eco-Management Audit Scheme.

The fully-robotised welding facility at Ellesmere Port.

Since the early 1980s, Vauxhall has become closely integrated with General Motors Europe.This partnership gives Vauxhall direct access to an extensive technical,purchasing and manufacturing network.

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InvestmentAll manufacturing facilities havereceived high levels of investmentdirectly aimed at quality and efficiencyimprovements. A massive 200 millionwas invested in the Ellesmere Portplant, giving it the potential to pro-duce 42 Astras per hour, or around140,000 vehicles per year.

The dealer networkVauxhall customers are served by over530 dealerships in the UK. Sales staffat these dealerships have been trainedto advise customers about all aspects ofthe Vauxhall range of vehicles andaccessories. Each dealership is commit-ted to providing the very highest levelof service covering all aspects ofmotoring, from purchase and deliveryto aftersales.

Built to orderOnce the customer has decided on themodel and specification and confirmedhis or her order, the dealer places itwith General Motors Europe Ordering

Scheduling System. The order details acars full specification including anyfactory options such as an automaticgearbox, sunroof or special wheels.After processing, the order is transmit-ted to the appropriate plants inGeneral Motors Europes network ofproduction facilities.

ExportsThe UK factories can also build lefthand drive vehicles for other Europeanor Asian countries. This translates intoexport business for Vauxhall, which, in1993, received the Queens Award forExport.

At the PlantThe full specification of the vehicle issent by the Order Scheduling Systemin Europe to the Data General

Computer at the plant. This computercontrols production, ensuring that acustomers order is adhered to strictly.

The Material Production Control(MPC) process ensures that compo-nents arrive on the production line inthe right order, at the right time, andto the correct specification.

This is quite an achievement whenone car could be a red four-doorsaloon and the next a blue five-doordiesel hatchback. The process of build-ing a fully-inspected and testedVauxhall car takes less than 30 hours.In the following pages we will look ateach stage of the process.

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A transporter being loaded with Vectras

bound for customers.

A modern Vauxhall dealership.


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1. The press shop

2. Sub-assembly2a. Underbody pressings2b. Front end pressing2c. Body side pressings2d. Roof pressings2e. Door pressings.

3. Body building3a. Underbody & front end joined3b. Body sides added3c. Roof added3d. Doors, bonnet, wings and

tailgate added

4. Paint shop4a. Body anti-corrosion

protection ELPO dip4b. Spray primer 4c. Spray colour 4d. Wash and wax protection

5. Trim5a. Doors removed, wiring harness,

glass, headlining and trimitems fitted

5b. Dashboard assembly5c. Door trimming5d. Dashboard installed5e. Carpets and other trim fitted5f. Seats fitted

6. Final assembly and Inspection6a. Axle, power unit, petrol tank

and silencer installed6b. Wheels on6c. Doors re-fitted6d. Petrol in6e. Headlamps, brakes and wheel

tracking set6f. Roller tests and brakes tested6g. Conditioning and valeting6h. Engine underbody protection6i. Drive-away

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The modern motor car is assembled from as many as 9000individual parts gathered from all over the world. Up to 70per cent of the components used by Vauxhall are sourced

in the UK. Hourly, truck-loads of materials arrive atVauxhalls factories, where the components and raw mate-rials are assembled into cars.

The production process at Ellesmere Port

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The Press Shop Sub-assembly Body Building

The Paint Shop

The Trim Shop Final Assembly and Inspection

One of the state-of-the-art robots used to

build Vauxhall Astras at Ellesmere Port.


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The Press Shop at Ellesmere Port cov-ers 28,000 square metres, which is anarea equivalent to three football pitch-es, and includes a 3,716 square metresteel store. Here, 64 machines, eachthe size of a house stamp-out highquality pressed steel panels.

A substantial part of a 46 millioninvestment in Ellesmere Ports pressshop went into the installation of theHigh Speed Coil Cut Line which cutsthe coil steel to the required sizes.

The cut steel is then loaded onto

the Schuler Tri-Axis Large TransferPress which can exert pressures of3,200 tones. With improved efficiency

and lower operating costs, the fully-automated Transfer Press is capable ofproducing 1,000 car body panels perhour - the same rate as four conven-tional press lines.

The steel is moved around by 15radio-controlled overhead cranes,some capable of lifting 50 tonnes, theweight of an army battle tank.

All scrap steel is returned to thesteel mill for reprocessing as part ofVauxhalls commitment to reducewaste and increase recycling as part of

good environmental practice.After careful inspection by skilled

operators under special lighting thenewly-formed steel panels move on tothe next stage in the manufacturingprocess - sub-assembly.

Body pressings are meticulously inspected by

skilled operators.

The Schuler Tri-Axis Large Transfer Press at

Ellesmere Port - capable of producing up to

1,000 panels per hour.

Car construction starts in the press shop, where coils andsheets of high quality steel are cut and formed into bodypanels.

1 - The Press Shop - stamping out the body parts


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The inner door panel assembly goesthrough an automatic, four-stagewelding and transfer machine, whilethe outer panel is produced on a self-contained, multi-weld fixture. The twosections are then married (clinchedtogether by hemming and a finalwelding process) before passingthrough a special oven which sets thepanel-to-panel adhesive.

Front and rear floors come togeth-er to form the underbody assembly.They are processed through two sets

of multi-weld machines before beingjoined by the frame that will supportthe engine and transmission.

As elsewhere in the process, preci-sion welding and handling techniquesare utilised in bodyside production.

Part-welded sides are loaded into acarousel-type frame that is designedspecifically for each body type and is

jig-built to guarantee consistentlyaccurate build quality.

As the assembly moves from sta-tion to station, robots carry out theirprogrammed welding tasks. Eachrobot has a self-monitoring system tocheck its weld position and quality.Manual work is limited to the applica-tion and loading of the inner part ofthe assembly.

The underbody is placed on aconveyor skid, which will transportthe car to the various assembly andproduction processes throughout theplant. It is here that a transponder isattached to the underbody so that thecar can be tracked throughout theplant. This electronic device interactswith the production control computeridentifying the specific componentsrequired for that customers order. Awritten manifest also accompanies thecar, so that physical checks can be

made at any time during the manufac-turing process.

Laser welding a Vectra bonnet. The Luton

Plant was one of the first vehicle manufactur-

ing plants outside Japan to employ laser weld-

ing in high volume production line operation.

Laser welding is so precise that heat does not

reach the outer skin of the panel where it can

distort and discolour the surface.

The component sub-assembly area builds the front andrear doors, tailgates, facing panels and roof assemblies onfully-automated production lines.

2 - Sub-assembly - putting the pieces together

Robotic spot welding of the Vectra wheel arch.

The robotised underbody line

at Ellesmere Port.


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The body shop houses sophisticatedautomatic equipment that assemblesparts and bodies. With over 150 robotsperforming a variety of recurrent tasks,a body will receive nearly 4,500 robo-tised welds during its construction. Asmany as 2,200 spot welds and as muchas 2.1 metres of continuous weld areused to assemble over 100 individualpressings that make up the body of acar.

People in harmony with roboticsweld the body parts together to an

accuracy of less than 100th of a mil-limetre. By the end of 1995 the com-pany had over 400 robots in service atthe Luton plant.

ConstructionInitially, the underbody, front andbody sides are pieced together toform the skeleton of the vehicle.These components come togetheron the computer-controlled body fram-ing line. This part of the process relieson human skills with men andmachines working together throughthorough checks to ensure the dimen-sional quality and the perfect fit ofpanels. The bodyside framing unit

includes a robotic welding station fea-turing three pairs of side gate fixturesto cater for the range of body styles.

The roof panel is then presented tothe body before reaching the weldingstation where two pairs of robots tackthe front and rear joints, then weld thesides. Twelve more robots, supplement-ed by manual welding complete theframing by tacking spots not reachedby the jig-welding operators.

The Body in White

At the end of the framing line, thebody receives the doors, bonnet, tail-gate and front wings which have beenbuilt separately. The completed body isnow in the state known as body inwhite.

Once the main structure of thebody is complete, preparation of themetal surface for painting can begin.Highly skilled and experienced opera-tors use a combination of sight andtouch to detect and then eliminate anyimperfection.

Quality, a key factor in Vauxhallsbuilding process, is exemplified by theComputerised Coordinate MeasuringMachine or CMM. This equipment isable to measure build accuracy to with-in 100th of a millimetre at an infinite

number of locations on the body. Toensure build consistency, regular sam-ples taken from the production line aremeasured by the CMM in over 150locations around the body.

Cooling SystemWelding equipment reaches very hightemperatures and must be cooled tomaintain efficiency. This is achieved bypumping water continuously throughthe equipment.

At the Luton Plant, much of the

nine million litres of water used forthis purpose are pumped from a reser-voir in hills above the factory where itcools and is re-circulated back to theplant. This system ensures that anabsolute minimum of water is drawnfrom the towns supply. The samereservoir also provides the fire protec-tion system for the plant.

Robotic welding of the Vectra body.

The completed sub-assemblies now progress to thecomputer-controlled body framing line where they arewelded together to form the complete body.

3 - Body building

Experienced operators use sight and touch to

detect any imperfections.

The body in white line where the sub-assem-

blies are added to form the complete body.


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The bodyshell is now transferred tothe continuous conveyors that willcarry it throughout its journey. Themetal surface must be completelyclean before any paint can be applied.After being cleaned by hand toremove any grease deposits, it entersthe Phosphate Plant where it passesthrough four timed processes - twodegreasing dips followed by a sprayand immersion rinse and then thephosphate dip. In this final processcorrosion resistance as well as paint

adhesion are improved when zincphosphate crystals are deposited ontothe metal surface while it is immersedin an acidic bath.

The last stages of preparationinvolve the bodyshell being passedthrough a chromate rinse no less thanfour times to even out the crystaldeposits left by the phosphate dip.The demineralised rinses use purewater from Vauxhalls own purifica-tion plant. Water is continuouslyrecirculated to filter out impurities.

The next stage is to blow-dry thebody until it is slightly damp ratherthan bone dry, saving even moreenergy.

Electro-depositionElectro-deposition of polymers,ELPO for short, is Vauxhalls state-of-the-art process designed to ensure thatevery part of the body is coated with awater-based, anti-corrosive primer. Theuse of water-based paints is part of thecompanys environmental policy.

During the electro-deposition thebody is again completely immersed,this time in a mixture of primer anddemineralised water. An electricalcharge created between the body and

the immersion tank, forces the parti-cles of primer out of the water andonto the metal surface to create aneven, run-free film.

When the bodyshell leaves theimmersion tank it passes through aseries of water rinses to remove anyloose particles. It is then baked so thatthe primer particles are bonded togeth-er to form a tough even coating.

After being allowed to cool, thebodyshell is given a moist sand afterwhich a PVC finish is applied to the

weld seams and areas of the under-body vulnerable to stone chipping.Automated sprayers complete thisstage, with skilled workers performingthe more intricate work using specialspray guns.

In this same area, sound insula-tion panels are applied to the floor ofthe body as it continues its journey tothe top-coat areas.

Vauxhalls six-year anti-perforation warranty on its new cars,has been made possible through attention to design, highbuild quality and extensive investment in paint processes.

4 - The Paint Shop

The paint mix room at Ellesmere Port auto-

matically delivers waterborne primer.

A bodyshell emerges from the ELPO tank.

The Facility Monitoring and Control System

provides detailed and instantaneous informa-

tion on the status of all Paint Shop operations.


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Clean-room technologyContamination by airborne particles isof great concern in the Paint Shop.Vauxhall has invested heavily in clean-room technology to ensure the high-est standard of paint finish.

Filtered air is used to slightly pres-surise the spray booths, providing anairflow out of the spray area.

This technique, which is similar tothat used in a modern hospital operat-ing theatre, restricts the entry of air-borne particles. As a further precautionall Paint Shop personnel wear speciallint-free garments to avoid the risk ofclothing fibres being released into thepaint spraying areas.

The first coat of paintThe body now moves through a seriesof spray booths where the transpon-

der, attached during the framingprocess, triggers the required sprayprogramme for each customers order.Any sequence of colours and f inishescan be accommodated by the PaintPlant. This means that it is possiblefor one vehicle to be sprayed metallicblue, another pearlescent red, the nexta solid colour such as yellow or evenwhite. In practice, metallic andpearlescent finishes are applied indedicated booths.

Each spray booth contains eighteencomputer-controlled spinning bellspray heads. These rotate at 28,000rpm to atomise the paint, which isthen electrostatically charged at 90,000volts to cause the paint to be attractedto the earthed car body.

This method of spraying is estab-lished technology. However, a new andmore compact overhead line trackingsystem has been installed for the newVectra. Because this system offers

greater reach than before, the spray

head can extend further into the gapbetween each vehicle and give greaterpaint coverage of the front and rear ofthe body. The major benefits of thissystem are the increased line rate andreduced need for hand spraying.

Some spraying however is stilldone by hand in areas such as the inte-

rior, boot and under-bonnet. Aftereach spray booth the bodies passthrough an oven where the paint is

cured at 175 degrees C.

Time for the badgesAt the end of the paint process, thebody is absolutely clean and humidi-ty/temperature conditions are idealfor the application of contact adhe-sives. Consequently the body sidemouldings and badges, which werepreviously applied in the Trim Shop,are now fitted before the body leavesthe Paint Shop.

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Badges and mouldings are nowapplied in the paint shop.

The Paint Shop ovens have a heat recovery

system to save energy.

Spinning bells rotate to atomise the paint.

State-of-the-art spray booth at Luton.


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More anti-corrosion treatmentJust prior to entering the Trim Shop,the body goes through another stagein Vauxhalls extensive anti-corrosionprocess. Two automated machinesinject as much as 15 litres of anti-cor-rosion wax into the underbody boxsections. This sophisticated processaligns 80 nozzles with the underbodybefore delivering the correct amountof wax, then the overhead liftingdevice gently rocks the body fore andaft to distribute the wax evenly.

Into the Trim ShopThe body now enters the Trim Shop

where the doors are removed toimprove access for the assembly line

team. The exterior components suchas bumpers and lights are carefully fit-ted, together with all the interiorcomponents including the steering,airbag and electrical systems.

In 1984, Vauxhall's Ellesmere Portplant became the first UK car manu-facturing facility to use off-lineassembly techniques in the trim shoparea. A major advantage of this sys-tem, now employed in all Vauxhalltrim areas, is the ability to test thevarious modules before attachment tothe car. The instrument panel anddoors are examples of modules thatare fully assembled and tested off the

main car assembly line utilising Justin Time principles.

The instrument panel com-ponents arrive at the plants shortlybefore being sub-assembled andchecked by an umbilical tester knownas ECOS (Electrical Check OffSystem). The fully-tested modules arethen ready to be installed.

Traditional skills and automation combine in the Trim Shop.

5 - The Trim Shop

Preparing a Vectra cockpit module

for installation.

It is here that the car unites with themajor mechanical assemblies such asthe engine and transmission unit, sus-pension, wheels and brakes. This stageis monitored by computer, thus ensur-ing that the right mechanical compo-nents are fitted to the appropriate car.

The body is now raised well abovethe ground and special carriers careful-ly raise the engine and transmissioninto their locations, where the assem-bly line team position and fix theminto place.

The car progresses on through finalassembly where fully-prepared roadwheels and tyres are added. It is at thispoint that the exhaust system and cat-alytic converter are also installed.

The doors, originally removed atthe start of the trim process, are nowre-attached, fully trimmed and tested.

Final inspectionWith oil, water and fuel added, the caris finally capable of moving under itsown power. A series of comprehensive

checks and final adjustments must nowbe completed before the car can bereleased.

Roller-testing monitors mechanicalspecification and exhaust emissions,while Assembly Line Diagnostic Links(ALDLs) ensure engine managementsystems and anti-theft alarms are func-tioning correctly.

Brakes are checked and water testsconfirm the integrity and fit of door,window and sunroof seals.

In addition, the ECOS systemexecutes a final inspection of the elec-tronic components and the extendedECOS System examines models fittedwith automatic transmission and anti-lock brakes with integrated self diag-

nostics.Finally, a protective film of wax is

applied to the vehicle before it leavesthe factory. Vehicles destined forexport go directly to the sea ports.Vehicles for the domestic market aredelivered to dealers from one ofVauxhalls five Regional DistributionCentres.

The fully-trimmed car joins the marriage conveyor.

6 - Final assembly and inspection

The Marriage of a Vectra Estate body and

its mechanical units.


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Every effort was made to ensure that the

contents of this publication were accurate and

up-to-date at the time of publication.

As part of Vauxhalls policy of environmental

care, this publication was printed on paper

manufactured using Totally Chlorine Free Pulp

from specially farmed, sustainable timber

resources.

Published Summer 2001

The Public Affairs Department

Vauxhall Motors Limited

Osborne Road

Luton

Bedfordshire

LU1 3YT

www.vauxhall.co.uk

VM0102747

how we build a car

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