Tire And Wheel Safety Awareness Presentation

TIRE & WHEELSAFETY AWARENESS

OBJECTIVESIncrease YOUR Awareness On: Industry Injuries & fatalities. Pyrolysis Damaged & Abused Tires Wheel Information & Tracking Damaged Wheels. Tire Smart Practices Video Safety Instructions -Working with tires & Wheels Tire Maintenance For Your Own Car or LightTruck.

INDUSTRY INJURIES&FATALITIES

A 3200lbs car traveling at 90 KPH and hits a brick wall, it wouldproduce over 300,000 lbs of forceIt only takes 9lbs of force to fracture a human boneIt only takes 300lbs of force to fracture a human skull26.5 x 25 tire at 90 psi has373,650 ft/lbs of stored energy

Investigation into the main cause ofa fatal tire explosion during oxy-acetylenecutting of wheel studs on 21 April 2004 in aworkshop at Malta No. 3 Mine in Mpumalanga16 July 2004Rev: 00Christo Grobler Consulting Engineer cc

Rev 00 – 16/07/04

Rev 00 – 16/07/04

Rev 00 – 16/07/04

6.1mtireDeceasedRev 00 – 16/07/04Rim

Rev 00 – 16/07/04

PYROLYSIS

Pyrolysis Another less frequent, but potentially catastrophic tire andrim failure mode is gaseous explosion. Tires can explodefrom ignition of gaseous vapors resulting from chemicalreactions within the tire. The rubber liner of some tires will begin to Pyrolysis(decompose) at about 250 C. One product of rubberPyrolysis is an explosive vapor. The auto-ignitiontemperature of this vapor in one case was 428 C. It onlytakes a small amount of rubber liner to Pyrolysis to createenough explosive vapor that when ignited creates anexplosive pressure that will rupture the tire. Definitions – Pyrolysis: The decomposition of a substanceby heat.- Auto-Ignition: The self-ignition or spontaneouscombustion temperature of a substance (usually fuel)without the help of a spark or flame.

PyrolysisCase Study 1 An accident that occurred at an Ontario naturalresources firm would appear to have been caused byPyrolysis and ignition by localized heating of the rim.A welder had partially deflated a tire to about 30 psi,and began to weld a steel rim to seal a leak. A sixinch weld on the rim was made. This are wasquenched with water and inspected and found to stillleak. A second weld of about six inches was made,and as the welder began the third pass, the tireexploded. The explosion resulted in the welderfatality.

PyrolysisCase Study 2 Another heat source that can initiate rubber linerPyrolysis is wheel fires. In this case, the rear wheelscaught fire due to overheated brakes (emergencybrake remaining engaged). When one tire exploded,eyewitnesses reported a large fireball that eruptedskywards. The force of the explosion blew thedemountable flange off the rim, and fragments ofrubber were hurled up to 100m.The other tire which caught fire did not explode wasfound, upon examination, to have a partly Pyrolysisinner liner. This tire was probably close to exploding.

Pyrolysis

Tire Over-Heating InformationIf a tire is suspected of being over-heated (Smell burning rubber) the scoop or truckshould be parked immediately, roped off and let sit for “several hours” and do notapproach the tire and wheel until the tire and wheel assembly cools down. The riskof explosion is greatest soon after the vehicle is stopped. When the machine isstopped cooling air does not circulate. Once the tire has cooled down it should bedeflated and removed and sent for a proper inspection.Besides tires that are under-inflated and or over-loaded, another cause of heatbuildup in the tire could be caused by overheating or seized brakes. External heattransferred from the hub to the wheel and tire.Another damage that can cause tire separation is an impact break to the tire. Thishappens when the tire runs over debris such as large chunks of muck while loadedand causes the tire to over-deflect causing the casing to break. The tire doesn’talways fail immediately; it could fail sometimes on the next shift depending on theseverity of the impact damage.

BASIC TIREINFORMATION &REMOVAL REASONS

High Tensile Strength Steel Bead Core Rugged foundation for thetire Anchors tire firmly andairtight to rim and providesdesired stiffness just abovebead area Withstands radial forcesresulting from inflationpressure Cushions and protectstough bead wires duringmanufacturing and aftermounting on rim

Steel Cord Radial Body and Sidewall Reinforcements Immensely strong wire cordsrun bead to bead, containingair pressure and forming mainbody of the tire Deep steel body ply turnup onoutside helps resistseparation and penetration Endures repeated flexing forbetter ride Continuously transmitspowerful torque forces frombead to tread Reduces internal stressesduring operation for extendedtire life

Goodyear Unisteel RL-4 Radial Tread and Sidewall Unique curved lug and groovedesign for maximum traction Radial design lower rollingresistance gives improved fuelmileage Steel belts increase treadstiffness for long running life Added rubber in shoulder areafor increased cut protection Specially formulated sidewallcompounds resist weathering,cracking, gouging Improved flotation from radialtype construction, togetherwith smoother ride for lessequipment damage, reducedoperator fatigue

Bead Core Bias ply off-road tires haveextremely strong steel wirebeads -- up to four beads,depending on tire size Bead core componentsmaintain proper tire to rimfitment

Nylon Cord Body Multiple plies of tough nyloncord make up tire carcass Transmits bending forcesand forms basic container forinflation pressure No steel sidewall areaprotection as in radial tires

Hard Rock Lug XT-8 Bias Type Tread and Sidewall Provides good traction andlong wear for bias type tire Thick sidewall and shoulderareas contribute to hotterrunning, lower TMPH thanradials No working steel belts Flotation not as good as radial Less fuel mileage than radial

BASIC OFF ROAD TIRE PROBLEMNORMAL RUNNING CONDITIONSPASSENGER TIRES65-68% OF THEIR RATED LOADOVER THE ROAD TRUCK TIRES92-98% OF THEIR RATED LOADOFF ROAD TIRES100% OF THEIR RATED LOAD

COMMON TIRE REMOVALCAUSESREMOVAL CAUSEOPERATING FACTORSTIRE FACTORSTREAD CUTS* UNDERFOOT CONDITIONS* PROPER INFLATION* TREAD PATTERN* CUSTOMIZED CODE* CONSTRUCTIONSIDEWALL CUTS* UNDERFOOT CONDITIONS* HAUL WIDTH* SIDEWALL COMPOUND* CONSTRUCTIONIMPACT BREAKS* UNDERFOOT CONDITIONS* PROPER INFLATION* TIRE LOADING* INFLATION PRESSURE* TIRE LOADWEAR OUT* UNDERFOOT CONDITIONS* TREAD COMPOUND* CONSTRUCTION

OPERATING CONDITIONSEXCESSIVE WATER Water Acts as a Lubricant for Rubber. Over Watering Leads to Cuts in Tires. Limit Watering to Control Dust. Wet Tires Cut more Easily than Dry Tires.

Debris May Not All Be Visible

TREAD CUT

POOR OPERATING CONDITIONS

SIDEWALL DAMAGEParking Truck To Close to Cement Wall.Must Try & Avoid Heavy Pressure Against Sidewall.

OPERATING CONDITIONSDEBRIS

TORO 40DHeavy Build up of Ore.Must be Clean to Avoid Tire Damage.

OPERATING CONDITIONSDEBRISMetal PipeNovember 2010November 2010

OPERATING CONDITIONSDEBRIS

OPERATING CONDITIONSDEBRIS

OPERATING CONDITIONS

TIRE REMOVAL REASONImpact Breaks

TIRE REMOVAL REASONOver deflection Run Flat / Overload

Effect of Tire Overload / UnderinflationTIRE LIFE vs TIRE OVERLOAD160% TIRE LIFE14012010080604020080100120% LOAD140160

Correct Tire Inflation Note: A Tireis determined to run flat whenoperated below 80% of the recommended coldinflation pressure and should be removed fromservice

Correct Tire Inflation Assuresload carrying ability Reduces incidence of run lowor run flat Reduces incident separation failures due toover deflection Reduces impacts and tread cutting due to overinflation Saves money

WheelInformation&Tracking

Wheel AssembliesOne Piece Wheel

Wheel Assemblies

Wheel Assemblies5 Piece WheelRIM BASE

Why track and maintainrims? 26.5-25 (ST8B) tire at 90psi has373,650 ft/lbsof storedenergy.

Visual Rim Inspection Gutter sectionBack sectionPuller nutsStud holesBolting plate weldRim base weldsGeneral conditionRun flatCheck last NDE

Magnetic ParticleInspection Bolting platewelds Gutter section Rim base welds Rim baseadjacent tobolting plate Back section

Rim Tracking

View Rim Number

DAMAGED WHEELS

ST8B WHEEL Portion of rimcut withtorches to beable to get atthe nuts witha socket. The tire wasnot deflated!!!!

CLOSER LOOK

50 TON TRUCK (BENTFLANGE) Tire was removed from truck withseverely bent flange. The tire was not deflated !!!!!

SAFETY INSTRUCTIONSWORKING WITHTIRES ANDWHEELS

DEMOUNTING PRECAUTION REASON FOR- Always exhaust all PRECAUTIONair- A broken rim and orcomponent under- from a single tirepressure can blowand from bothapart and causetires of a dualserious injury or death.assembly prior to- When you remove theremoving any rimlugs, if the tire is undercomponents orpressure, the assemblywheel componentsmay fly apart withsuch as nuts andexplosive force.rim clamps.

DEMOUNTING PRECAUTION - Remove valvecore completely, this will assure allair is exhaustedthe tire.- Remove bothcores from a dualassembly.- Run a piece ofwire through stemto be sure it’s notplugged.REASON FORPRECAUTIONForeign material mayclog valve stem duringdeflation.Ice may form as the airleaves the tire, this mayclog the valve stem.

DEMOUNTING PRECAUTION REASON FORPRECAUTION- Always standclear during- If the assemblydeflation.bursts, the operatorsshould be far from theexplosive force.

DEMOUNTING PRECAUTION REASON FORPRECAUTION- Use approvedeye protection. - To protect eyes fromdust and dirt whenexhausting air fromthe tire.

INSPECTION PRECAUTION REASON FORPRECAUTION- Check rimcomponents for : - Parts that arecracked, damaged or* Cracksexcessively rusted* Badly wornwill be weakened.* Damaged / Bent - Bent or repaired* Severely rustedparts may not seatproperly on rimbase.

INSPECTION PRECAUTION REASON FORPRECAUTION- Never under anycircumstances,- Heating mayattempt to rework,weaken aweld, heat or brazecomponent.any rim- It may then becomponents thatunable to withstandare crack broken ordamaged.forces of inflationor operation.

INSPECTION PRECAUTION - Do not re-inflate a tirethat has been run flat orunder inflated until aproper inspection of :* tire , tube and flap* Rim and wheel assembly- If the tire is less than80%of it’s recommended airpressure, the tire shouldbe recognized as flat orgoing flat.REASON FORPRECAUTIONComponents can bedamaged ordislocated when a tireis run flat or underinflated.The tire may beweakened do to overdeflection andextreme heat buildup.

INFLATIONTIRE SIZEEQUIPMENT TYPERECOMMENDEDOPERATINGPRESSURE26.5R25** L-5 SMOOTHST8B WAGNER SCOOP100 PSI80 PSI17.5R25** L-5 SMOOTH3.5 YARD SCOOP94 PSI75 PSI15.5R25* L-2 LUGREAR MINECAT35 PSI28 PSI12x16.5 LUG 10 PLYFRONT MINECAT35 PSI28 PSI35 PSI28 PSI55 PSI44 PSI16.9x24 G-2 LUG 10 PLY13/70x18 AIRCRAFTFRONT MANITOUFORKLIFTREAR MANITOUFORKLIFT80% REMOVALFACTOR

MOUNTING ANDINFLATING PRECAUTION REASON FORPRECAUTION- Never sit on orstand in front of a - Components maytire and rimnot be seatingassembly that isproperly and can flybeing inflated.apart with explosive- Make sure allforce.workers are awayfrom the line oftrajectory.

MOUNTING ANDINFLATING REASON FOR PRECAUTIONPRECAUTION- Never attempt - Heat from welding willto weld on ancause a drastic rise inpressure, this can resultinflated tirein an explosion with theand rimforce of a bomb.assembly.- Welding will weaken thesteel molecules of therim and it’s components.

OPERATION PRECAUTION REASON FORPRECAUTION- Always inspectrims and wheels - Early detection offor damagepotential rim failuresduring circlemay prevent seriouschecks.injury.

OPERATION PRECAUTION REASON FORPRECAUTION- Never modify arim without- Modification orprior approvalheating can severelyfrom theweaken the rim.manufacturer.- It may not withstand- Never heat,inflation or operation.weld or braze arim or wheel.

SERVICING TIRE AND RIM ONMACHINE PRECAUTION REASON FORPRECAUTION- Before looseningnuts and or- Unsecuredclamps. Alwaysassemblies maysecure a tire andfall when fastenersrim assembly withare removed.a sling , tirehandler or othersupportequipment.