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Technical Information No. 02 All About Spark Plugs www.beru.com The specialist for ignition, diesel cold start, electronics and sensorics
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Page 1: TI02_en

TechnicalInformationNo. 02

All About Spark Plugs

www.beru.com

The specialist forignition, diesel cold start,electronics and sensorics

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Contents

The spark-ignition engine

Function of the spark plug in a spark-ignition engine

Requirements of a modern spark plug

Spark plug design and types

Materials

The spark plug in detail

Electrode gap

Spark position and sparking distance

Sealing seat

Thermal rating and thermal conduction

Thermal rating/influences

Thermal conduction

Beru spark plug range

Beru Ultra

Beru Ultra X

Beru Ultra X Platinum

Special spark plugs

Workshop tips

Spark plug testing

Faults and wear

Spark plug installation

Beru assembly aids

Historical review

Development of the spark plug

Beru history

Spark plug production

From blank to precision component

Beru hardness tests

Beru quality standards

Beru services

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Starting characteristics, service life, performance, fuel

consumption, and exhaust performances – these critical

engine parameters are all influenced by the spark plug. The

functional part of the spark plug is concealed within the

engine’s combustion chamber; only a part of the insulator

and connector are visible from outside.

During operation, spark plugs have to deliver outstanding

performance: in all situations they must produce a spark

reliably, ensure correct cold starts, and prevent misfiring –

even under extreme conditions – playing their part in

ensuring optimum combustion with low emissions.

They have to cope with temperatures in the combustion

chamber of up to 3,000 °C and pressures of up to 50 bar,

not to mention ignition voltages of up to 40,000 volts.

Chemical influences too make high demands on quality.

Heavy-duty work, which the spark plug has to sustain for

many thousands of kilometers.

Beru spark plugs are highly specialized, precision com-

ponents, which have been developed to meet vehicle

manufacturers’ specifications and are produced on modern

production lines.

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The spark ignition engine

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The ignition system on petrol-driven engines – by contrastto diesel engines – is external: during the compressioncycle the combustion of the compressed fuel-air mixtureis triggered by an electrical spark which is produced bythe spark plug. It is the task of the spark plug to generatethis spark. Created by the high voltage produced by theignition coil, it leaps between the electrodes. A flamefront spreads from the spark and fills the combustionchamber until the mixture has been burned. The heatreleased increases the temperature, there is a rapid build-up of pressure in the cylinder and the piston is forceddownwards. The movement is transferred via the connec-ting rod to the crankshaft; this drives the vehicle via thegears and the axles.

In order for the engine to operate smoothly, powerfullyand in an environmentally friendly manner, a number ofrequirements have to be met: the correct amount ofperfectly balanced fuel/air mixture must be present in thecylinder, and the high-energy ignition spark must leapbetween the electrodes precisely at the specified moment.A spark plug must deliver a powerful ignition sparkbetween around 500 and 3,500 times a minute - even afterhours of maximum performance or in stop-and-go trafficconditions. Even at -20 °C, they have to ensure that theoperating temperature is reached as quickly as possible.High-tech spark plugs provide low-emission combustionand optimum fuel efficiency – without misfiring, whichcan cause unburnt fuel to get into the catalytic converter,destroying it. A modern spark plug must meet the follo-wing requirements:

Electrical requirements� Reliable high-voltage transmission, even at ignitionvoltages of up to 40,000 volts

� Good insulation capability, even at temperatures of up to1,000 °C, prevention of arcing and flashover

Mechanical requirements� Pressure-tight and gas-tight sealing of the combustionchamber, resistance to oscillating pressures up toapprox. 100 bar

� High mechanical strength for reliable installation

Thermal requirements� Resistance to thermal shock (hot exhaust gases – coldintake mixture)

� Good thermal conduction by insulator base and electrodes

Electrochemical requirements� Resistance to spark erosion, combustion gases and residues� Prevention of build-up of deposits on the insulator

The function of aspark plug

The demands onspark plugs

Beru spark plugs are designed and manufactured using high-quality materials toconsistently meet these extreme requirements. Even at the engine developmentstage, Beru engineers work closely with the motor industry to ensure that the sparkplugs are fine-tuned to specific conditions in the combustion chamber.

The spark from the spark plugtriggers the combustion of thecompressed fuel-air mixture duringthe compression cycle.

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Connection for the spark plug (4 mm thread,SAE screw connection or SAE fixed (mono-block)). Transfers the ignition voltage to thecentral electrode.

Gas-tight steel pin enclosed in the conducti-ve glass melt, forming a link with the centralelectrode.

Ceramic body insulates the central electrodeagainst earth up to 40,000 Volts.

Nickel-coated plug body forms gas-tightconnection with the insulator through theheat shrinkage method. Thread used tosecure the spark plug in the engine block.

Permanent outer sealing washer, for sealingand heat dissipation.

Electrical connection of spark pin and centralelectrode. On suppressed (R types) glass meltresistors.

Seals insulator in the plug body and used forheat conduction.

Nickel-based alloy additives increase thedurability of the earth electrode.

Enables the spark to pass to the earth elec-trode.

Enables spark plug to be screwed into engineblock.

Influences self-cleaning action and thermalvalue tolerance.

Nickel-based alloy additives increase thedurability of the earth electrode.

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Materials

Electrode gap

Beru offers a wide range of spark plugs to ensure thatthe optimum spark plug is always available for the manydifferent engine types and applications. Diverse materialsare used for the center electrodes. Special nickel-basedalloys and copper-core electrodes offer good thermalconductivity and high corrosion resistance. Silver has evenhigher thermal conductivity. Platinum offers excellentresistance to erosion, so it extends the length of timebetween replacements. The design of the ground electrodeis just as important. Its geometry influences mixtureaccessibility, wear, heat dissipation and ignition voltagerequirement, among other things. Its design can varyaccording to the shape of the combustion chamber.

The gap is what counts. The shortest distance between thecentral and earth electrode(s) on the spark plug is calledthe electrode gap. The ignition spark must jump this gap.The vehicle manufacturer specifies the relevant optimumelectrode gap – depending upon the engine. Maximumprecision in maintaining the electrode gap is importantsince an incorrect gap can have a considerable detrimentaleffect on the functioning of the spark plug and conse-quently the engine performance.

� If the electrode gap is too small this may cause misfiring,noisy action and poor exhaust levels.

� If the electrode gap is too large then a higher ignitionvoltage is required to enable the spark to jump the gap:this may lead to misfiring.

� The co-ordinated spark positioning on multi-electrodeplugs means the electrode gap does not have to beadjusted (for example Ultra X, air/glide spark technology).

Spark plug design and types

Ignitor Aluminum oxide insulator

Nickel-platedplug body

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4SAE terminal nut(cable connecting nut)

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ElectrodeGap

EA

EA

Ultra XPlatinum

Platinum core electrode

„The spark plug in detail“

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www.beru.com

Spark position andSpark distance

Sealing sit

The short spark path. The function of the spark plug in thecombustion chamber is influenced by two main factors:the spark distance and the spark position.

Spark position is the name given to the pattern of the sparkpath in the combustion chamber. Depending upon theelectrode and insulator fit, the spark ignites the mixture ata different position in the combustion compartment.

With regard to the spark distance, a distinction is madebetween:

� The air spark distance which denotes the path the sparktakes between central and earth electrode in order toignite the fuel-air mixture in the combustion chamber.

� The glide spark distance which denotes the path whichthe spark takes if it first passes over the surface of theinsulator tip before then jumping across to the earthelectrode. Taking this path burns off harmful deposits.

� Air spark distance/glide spark distance: spark distances,which can pass through air and the insulator. By combi-ning separate air spark and glide spark distances, elec-trode burn-off can be reduced, leading to a significantlyincreased service life for spark plugs.

The spark plug must be screwed into the cylinder head sothat it is gas-tight. Depending on the engine design, thereare two different types of seal:

� Flat seat or level seat: a captive outer gasket acts as a sealaround the plug body.

� Taper seat or conical seat: the conical surface of the plugbody fits into a correspondingly shaped contact surfaceon the cylinder head to create a seal.

In restricted spaces (e.g. multi-valve engines), FineLinespark plugs are commonly used, which require smallerwrench sizes and have smaller dimensions.

Captive outer gasket Innergasket

Center electrode

Insertion piece

Ground electrode

Electrically conductiveglass seal

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9

6

5

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7

Insulator nose

Breathing space11

10

Flat seatwithgasket

Wrenchsize 16

Conical seatwithoutgasket

Sparking distance

Sparking air distance

Surface gap

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Thermal rating

The influences on thethermal value

The thermalconduction

The thermal rating is a measure of the thermal rating of aspark plug. It indicates the maximum thermal loading on thespark plug in equilibrium between heat absorption and heatdissipation.

It is vital to choose the correct thermal rating when selec-ting a spark plug:

� If the thermal value characteristic is too high (for exam-ple thermal value 9) the plug is unable to dissipate theresultant heat quickly enough. This leads to incandescentignition; in other words it is not the ignition spark thatignites the mixture but the overheated plug.

� If the thermal value characteristic is too low (for exam-ple thermal value 5) then the free burning temperaturerequired in the lower revolution range for self-cleaningthe plug, is not reached. Result: misfiring, increased fuelconsumption and higher exhaust emissions.

The size of the insulator base is important. The higher theengine performance the higher in most cases the combus-tion chamber temperature as well. The size of the insulatornose has a critical influence on heat absorption; heat dissi-pation takes place through the insulator nose, the centerelectrode and the inner gasket on the plug body to thecylinder head.

� Spark plugs with a long insulator base absorb more heat.However, since they emit less heat on the long path tothe plug body they are called hot plugs.

� Spark plugs with a small insulator base absorb less heat.However, since they are able to emit a lot of heat on theshort route to the plug body they are called cold sparkplugs.

Cylinder temperatures of more than 3,000 °C are generatedduring the combustion process and these temperatures alsocause the spark plugs themselves to get very hot. The sparkplugs give off around 80 per cent of this absorbed heatthrough various methods of heat conduction (illustration).The vast majority of the heat is transferred from the plugthread directly to the cylinder head. The spark plug musttherefore always be screwed in with the correct torque. Thepassing fuel-air mixture only absorbs and dissipates around20 per cent of the heat.

If the spark position is extremely far forward in the com-bustion chamber, the self-cleaning temperature is quicklyreached, thanks to a special adjustment of the cross-sectionand the heat-absorbing surface of the insulator tip – andthe upper temperature at the insulator is adjusted to below900°C. This type of spark plug is therefore suitable for com-bustion chambers with both relatively low and very hightemperatures.

Thermal rating and thermal conduction

1.000 OC Auto-ignition area

Severe electrode wear

Self-cleaning range

Sooting

400 OC

850 OC

Operating range600-700 OC

approx. 2%

approx. 4 %

approx. 11%

approx. 63%

approx. 20 %

Heat path ofa spark plug

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6 Ultra X + 2 Ultra X Platinum = 8 superbtypes for 93 % market coverage!

Top-quality spark plugs in OEM quality – for the manydifferent engine types and applications.

� Environment-friendly combustion: saves fuel and pro-tects the catalytic converter

� Reliable ignition, even at low temperatures� Long service life, good durability� Proven materials: two-element center electrode withnickel-sheathed copper core

For every occasion. Beru manufactures special spark plugsfor a wide range of applications:

1. Compact spark plugs for the particularly confined spa-ces on power saws or lawnmowers

2. Fully screened spark plugs with steel jacket where verystringent demands are placed on suppression, forexample in official vehicles

3. Spark plugs for gas powered engines on gas drivenvehicles and stationary engines for industrial anddomestic use

4.Measurement spark plugs specially for test and trialengines

Beru Ultra X.The range forx-tremedemands.

Beru Ultra – thecar manufacturer’schoice.

Special spark plugs

Beru spark plug range

x-tremely strong rangex-tremely good market coveragex-tremely innovative:OEM technologies

The innovative spark plugwhich unites current originalequipment technologies.

The best Ultra X.For uncompromisingly perfor-mance-oriented drivers.

New: Platinum center electrodeNew: Even more spark pathsNew: Horn-gap electrodesNew: Duplex insulator

The Ultra X Platinum is designedfor the high demands of thelatest-generation engines, andoffers the uncompromisinglysporty, performance-orienteddriver the edge in performance,ignition reliability and overallreliability.

Ultra X the spark plug inno-vation developed for driverswho wants to profit from theseveral OEM technologies atthe same time.

Beru Ultra X. Beru Ultra X Platinum.

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A visual inspection of the spark plug can reveal a widevariety of damage patterns. Some of them are listed below,with a description of causes, effects and solutions:

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Workshop tips

Spark PlugAppearances

DepositsThe insulator tip, electrode and plug are covered with velvet-like black soot.Cause: Incorrect mixture setting. Mixture too rich. Air filter blocked, defective cold start system(injection). High proportion of short journey use. Thermal value of plug too high.Effect: Due to leakage currents, cold starting behaviour is poor and misfiring occurs. Thiscan result in unburned fuel reaching the catalytic converter and causing demage.Solution: Correction of mixture and cold start system. Check air filter.

NormalMinimal electrode burn-off and a gray-white/gray-yellow to russet-colored insulatornose: Engine settings are OK, thermal rating is correct.

Oiled-upInsulator tip, electrode and plug covered in black oil film.Cause: Too much oil in combustion chamber. Oil level too high, heavily worn piston rings,cylinders and valve guides.Effect: Misfiring or even shorting of the spark plug, complete failure.Solution: Overhaul engine, correct fuel-oil mixture, fit new, original Beru spark plugs.

Excessive depositsHeavy deposits of fuel and oil additives on the insulator tip and earth electrode. Slag typedeposits.Cause: Alloy deposits, especially resulting from oil build-up, which then settle in the com-bustion chamber and on the plug.Effect: Can lead to pre-ignition with loss of performance and engine damage.Solution: Check engine tuning. Fit new, original Beru spark plugs, possibly change the typeof oil used.

Glaze formationInsulator tip shows signs of brownish yellow glazing which could also appear to be greenin colour.Cause: Additives in fuel and oil forming ash-like deposits.Effect: Under excessively sudden full engine load, the glaze liquifies and becomes electri-cally conductive.Solution: Adjust fuel system exactly, fit new, original Beru spark plugs.

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Broken insulator tipSurface break up on the insulator nose.Cause: Mechanical damage due to incorrect use. Initially often only discernible as a hairlikecrack, sometimes caused by pinking. In extreme cases, deposits can from between the middleelectrode and the insulator, causing the insulator to shatter. Pinking.Effect: Misfire, spark “wonders“, not guaranteeing ignition.Solution: Fit new, original Beru spark plugs.

OverheatedCentre electrode melted. Blistered, sponge like and soft insulator tip.Cause: Thermal overload due to “glow ignition“ e.g. because of ignition timing set too early,combustible residue in chamber (coked-up), defective valves, damaged distributor, too weak afuel mixture and thermal value of plug too low, tightening torque not observed.Effect: Misfire, drop in output (engine damage).Solution: Check engine, ignition, mixture, tightening torque of the spark plugs. Fit new,original Beru spark plugs with the correct thermal value.

Excessive wear of the electrodeCentre or earth electrode shows visible signs of material loss.Cause: Aggressive fuel or oil additives. Poor flow in the combustion chamber, possibly dueto carbon build up. Pinking, overheating.Effect: Misfire, especially during acceleration (ignition voltage no longer sufficient, withlarge electrode gap). Poor starting performance.Solution: Fit new, original Beru spark plugs.

Extreme overheatingCauliflower-like deposits on the electrode leading to further deposits on the plug andother parts of the combustion chamber.Cause: Thermal overload due to “glow ignition“, e.g. through ignition timing set to early,combustible residue in chamber (choked-up), defective valves, damaged distributor, tooweak a fuel mixture, spark plugs incorrectly tightened.Effect: Prior to engine failure, efficiency (output) will drop.Solution: Check engine, ignition and mixture; check tightening torque of the spark plugs.Fit new, original Beru spark plugs.

Embrittlement of spark plug connectorCause: Thermal overload, old connectors.Effect: Misfiring.Solution: Fit new, original Beru adapter and spark plugs, grease insulator neck with Beruadapter grease (see p. 12).

1,61 mm1,59 mm1,29 mm1,25 mm1,24 mm

10 Nm20 Nm30 Nm40 Nm50 Nm

The correct tightening torque is essential fortrouble-free operation of the spark plug. Toohigh a torque can damage the plug, while toolow a torque produces a poor seal and heatdissipation.At the correct torque, the gasket thickness onthe spark plug is between 1.29 and 1.59 mm(see table, figures correspond to spark plugswith M14 threads).

Gasketthickness

Tighteningtorque used

1,22 mm1,20 mm1,19 mm1,17 mm1,15 mm

60 Nm70 Nm80 Nm90 Nm

100 Nm

Gasketthickness

Tighteningtorque used

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Workshop tips

Overload, poor fuel, wrong choice of spark plug, and stop-and-go traffic conditions are just a few of the factors thatcan lead to spark plug faults. Here is a short checklist tohelp you identify the fault:

The air/surface discharge spark plug with nickel-sheathedcopper core and 4 ground electrodes, arranged in pairs inan X shape, provides highly dependable ignition: the sparkhas up to 8 different ways of igniting the fuel-air mixture!

Faults and wear

Our tip for thetoughestrequirements:Beru Ultra X

Symptom Cause Possible consequences

Spark erosion, corrosion Thermal overload Melted electrodesWrong or poor fuel Incandescent ignitionIncorrect thermal value Misfiring

(due to larger electrode gap)

Incandescent ignition Residues in combustion chamber Piston damageFaulty valves Valve damagePlugs with incorrect thermal value Spark plug damageFuel with insufficient octane count

Knocking Fuel with insufficient octane count Uncontrolled rise in pressureWrong ignition timing and temperature can lead to pistonExcessive compression and spark plug damage

Misfiring Faulty, old, leaking spark plug Spark-over to insulator; furtherconnector misfiring

An Ultra X spark plug, replacedduring inspection: the insulatornose is free from deposits, bothground and center electrodeexhibit minimal burn-off.

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Spark pluginstallation

When installing plugs,it is essential to usethe correct tighteningtorque

As spark plugs are designed for specific engines, the cor-rect plug must always be used. Plugs with the incorrectthermal value, electrode gap or thread length can lead toreduced engine performance or even damage the engineand/or catalytic converter. Installing and removing themcarefully is also imperative.

� When removing them, make sure that no dirt gets intothe combustion chamber. First loosen the plug by a fewturns, then clean the plug shaft using compressed air ora brush, before removing the plug completely.

� Apply a thin film of Beru special grease (order no.0 890 300 029) to the spark plug insulator.

� When installing plugs, make sure that the plug threadand cylinder head bore are clean. With Beru spark plugs,a nickel coating on the plug body avoids the need forlubrication. Be sure to use the correct tightening torque(see table).

� Warning: If you drop a spark plug, do not use it. Eveninvisible damage can lead to misfiring and may evendamage the catalytic converter.

� Check spark plug connectors for wear. If you see signs ofembrittlement or hairline cracks, replace the adapters.

If extreme burn-off or melting occurs on the center elec-trode, despite using the specified tightening torque, thecause is almost certainly due to an uncontrolled combus-tion process (e.g. incandescent ignition or high-speedknocking). Possible causes include wrong ignition timing,discharge valve setting too small, unsuitable fuel quality,deposits in the combustion chamber, or too lean a fuel mix.

Torque in Nm, thread must not be greased

Plug thread Cylinder head

Cast iron Light metalM 12x1,25 15-25 15-20M 14x1,25 30-40 25-30M 18x1,5 30-45 20-35

M 14x1,25 15-25 12-20M 18x1,5 15-30 15-25

Flat seat plugs:

Conical seat plugs:

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www.beru.com

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Workshop tips

Beru assembly aids For easy and reliable spark plug replacement without tiltingthe wrench or cracking the insulator, we recommend the useof special tools.

Spark plug assembly aid ZMH 001 0 890 000 001

Name Beru code Beruorder no.

Spark plug assembly aid ZMH 002 0 890 000 002

Name Beru code Beruorder no.

Beru special grease, 10 g tube ZKF 001 0 890 300 029

Name Beru code Beruorder no.

Beru spark plugassembly aid ZMH 001the mechanic’s extended arm

THE PROBLEM In the engine compartment, space is tight. When fittingor removing the spark plug, the mechanic can injure or burn his handon the engine – or drop and damage the spark plug.

THE SOLUTION The Beru spark plug assembly aid, made of rubber, actsas the “mechanic’s extended arm”: it holds the spark plug securely, sothat it can be carefully removed or installed after loosening or beforetightening the plug.

Beru spark plugassembly aid ZMH 002reliable spark plug replacement without tilting

THE PROBLEM The relatively large opening in the spark plug shaftmeans that when fitting or removing spark plugs using an extension,there is a risk of tilting the wrench, causing the spark plug insulator tocrack. The consequence: misfiring due to sparks jumping across thecracked insulator can destroy the catalytic converter.

THE SOLUTION Simply insert the Beru assembly tool, suitable foralmost all vehicle models, into the 3/8” spark plug extension and pushit into the spark plug shaft. The wrench will now remain parallel to theshaft and cannot be tilted.

To prevent the spark plug connector from fusing to the spark plug neckand damaging the sealing lips, we recommend greasing the spark pluginsulator with Beru special grease. This also increases resistance tospark-over.

Area to be greased

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Long history. The history of spark plug development goes backfurther than that of the automobile: in 1860 Jean JosephEtienne Lenoir patented the invention of the spark plug forhis gas-powered engine. The new era of spark plug designbegan after the turn of the century with the battery-less,high-voltage magnetic ignition invented by Gottlob Honold.The battery ignition version, still used as standard today, onlyarrived on the scene during the 20’s. The insulating bodiesof the first spark plugs were made of porcelain. Althoughit looked good the material was not sufficiently resistant.It would break even if over-tightened. Trials with other mate-rials such as steatite, zirconium, sintered corrundum or micafinally led to the moulded insulation body made of aluminiumoxide granulate which is still currently in use today. The shapeof the electrode and choice of material have also undergonenumerous changes. Today, the dominant materials are chro-mium nickel alloys, silver and platinum.

Starting with the Ruprecht plug. In 1912 the 29 year oldinventor Albert Ruprecht, from Swabia, was granted thepatent for his ”Ruprecht plug”. Its main advance was that itwas gassealed against compression pressure. With the patentin his pocket Ruprecht set up his own company: Beru. The newplugs operated so reliably that Beru rapidly expanded andsoon became one of the leadingmanufacturers of spark plugs.

Numerous other patents and the expansion of the productionrange to include other components made Beru the expert invehicle electrics (diesel cold-start technology, electronics,ignition technology, sensor technology, etc.). Whereas in thebeginning the focal point of the interest was primarily onoperating safety and reliability of the plugs, today, in line withthe growing environmental consciousness, the attention isincreasingly being focused on the optimum mixture combus-tion. This is the only way to ensure optimum fuel consump-tion and minimal emission levels at the same time.

Historical review

The developmentof the spark plug

Beru history

On the left, the "Ruprecht plug", with which the history of Beru began in1912, on the right, the soapstone plug (1920).

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Spark plug production

Original Beru spark plugs are manufactured in our ownfactories on computer-controlled production lines – frompreparation of the ceramic materials for insulator produc-tion from high-grade aluminum oxide, to fitting of theouter gasket.

For bending and breaking. There is no compromise for sparkplugs in the everyday life of the car. Whether in stop-and-go traffic or long motorway trips, whether in the bitter coldor the burning heat of the sun – a Beru spark plug mustalways continue to function. And yet even the best Beruproduct is subject to natural wear and tear.

That is why the vehicle manufacturersstipulate specific intervals for repla-cing the spark plugs. The followinggenerally applies: the spark plugsshould be changed no later than everytwo years. This is aimed not only atmaintaining engine performance butalso protecting the expensive catalyticconverter which can be damagedthrough misfiring.

If we bear in mind the fact that,depending upon the number of cylin-ders and type of spark plug, a completeset of plugs can be bought for aroundjust 12 Euro but a new catalytic conver-ter can set you back at least 800 Euro,then you can see how important it is tocheck spark plugs regularly and repla-ce them within the specified period.

Generally: Indipendent of the annualdriving power the spark plugs have tobe changed after 2 years at the latestfor maintainance of the engine powerand protection of the catalytic conver-ter.

From blank toprecision component

The Beru hardnesstest

Testing an insulator at 40,000 Volts.

Testing the cold start response in the refrigerationunit at -30 °C.

Service life test – test bench

Aluminum oxide granules

Blank

Cold-flow press stages 1-6 Body turnedand drilled

Ground electrodewelded on, threadrolled

Electrode pre-shaped, bodylabeled, nickel-, zinc- orchrome-plated

Insulator moldedground smooth sintered labeled sprayed

with glazefired

Conductive glass

Center electrode(copper core withnickel sheath)

Nickel platedignition pin

Insulatorcomplete(glass mel-ted in)

Innersealantwasher

Outersealantwasher

Spark plugready installed

Spark plugwith electrodegap set

�� � �

������

��

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In order to compete at an international level, quality isparamount. All Beru plants are certified to internationalquality standards such as DIN ISO 9001:2000. In Germany,the plants also meet the requirements of ISO/TS16949 andDIN EN ISO 14001. The certificates are renewed at regularintervals and always correspond to the latest standards.

Around ten percent of all Beru employees are involved inquality assurance. One of the principles behind Beru’s qua-lity philosophy is production control rather than productinspection. That’s because quality has to be built in, notinspected in. Beru relies on qualified employees and thelatest, computer-controlled processes. This is the only wayto ensure that the specifications promised to the customerare reliably reproduced in every spark plug. Yet qualityassurance starts with the selection of suppliers and mate-rials: reliable partners and premium raw materials are fun-damental to uncompromising quality.

Today Beru is one of the world’s leading suppliers of elec-trical components to the automotive industry. As amedium-sized company, Beru is flexible and quick torespond to customers’ needs. Around 150 developers anddesigners are constantly working on optimizing existingproducts and developing new ones - in close associationwith customers from the car and engine manufacturingsectors. Special applications, specially tailored to Beru’spartners, ensure that vehicle manufacturers can rely onproducts that exactly match their needs. That is why Beruis increasingly offering complete system solutions insteadof individual components.

Beru quality standards

Beru services

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BERU AGMörikestraße 15571636 LudwigsburgGermanyPhone: +49(0)7141 132 366Fax: +49(0)7141 132 760E-Mail: [email protected]

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