横滨的新轮胎设计方法学

nullnull 　　Tire Design Methodology Based on Safety- Factor to Satisfy Tire Life 轮胎 设计 领导形象设计圆作业设计ao工艺污水处理厂设计附属工程施工组织设计清扫机器人结构设计 方法学(主要以安全和使用寿命的因素考虑),此方法同样适用与载重胎和BUS胎 Simulation Approach to Truck & Bus Tire Design 　　　　　　　　　 Kazuyuki Kabe The Yokohama Rubber CO.,LTD 14th China Tire Technology Conference2006.9.20nullContents目录1. Introduction 简介 2. Radial Tire Construction , Function & Characteristics特征 3. FRR (Characteristics of Cord & Rubber) 4. Introduction of Safety-Factors for rubber products 5. Simulation Approach to Durability of Rubber Product 6. Numerical Example: Truck and Bus Tire 7. Conclusionsnull IntroductionPurpose of This Paper : Proposal for the new design method considering actual condition of rubber products, for example a tire < TIRE SIZE > 12R22.5nullRadial Tire ConstructionBead CorenullBasic function required of a tire 1) Load - carrying capacity 2) Transmission of driving and breaking torque 3) Cushioning ability 4) Road - holding ability Other requirement And also Information center of a vehicle　 　Characteristics of TirenullΩσrubberεεσcordlarge deformation &large strainincompressibilitymaterial nonlinearitycomposite structureviscoelasitcityrolling contactCharacteristics of Tire 　nullRubber model in tire part Heterogeneous异型 structure model for carbon black filed rubber Quasi-glassy state (C phase)Liquid state (A phase)Cross linked rubber molecules (B phase)Carbon blackInteraction between C phasesnullReinforcemant of Elastomers: (edited by Gerard Kraus, Interscience Publishers, N.Y., 1965) Section 6:Microscopy in the Study of Elastomer Reinforcement by Pigment Fillers(by William M. Hess) Rubber in tire part by Microscopy Heterogeneous structure for carbon black filed rubber nullMechanical properties of cord & rubber From the above table Modulus of cord ≫ Modulus of rubber Breaking strain of cord ≪ Breaking strain of rubber nullIntroduction of Safety-Factors for rubber productsFRR(cord);rubber part;　The durability of rubber is evaluated by principal strain（belt layer, carcass layer）The durability of FRR is evaluated by stress(Margin of safety)(Safety-Factor)null Tire condition under operation: Tire profile growth & rubber aging due to heat build-up 2. It is necessary to take tire profile growth & rubber aging into consideration. 　　 　　 The new design technology considering actual condition, for example,Tire Simulation Approach to Rubber Product (1)null3. Introduction of the Safety Factor conceptTimeOLDNEWDangerous zone20Safety FactorMargin of Safety = Eb / ε(max) Eb = Breaking strain of rubber ε(max) = Maximum value of principal strain in tire partsSimulation Approach to Rubber Product (2) Safety zone10nullDouble Inflation Pressure Method　< NEW TIRE>Estimation ：Principal strain of belt edge fillerDeflectedDeflectedInflatedNew model Remodel < GROWN TIRE>InflatedDouble Inflation PressurenullTire size：11R22.5 < Test condition > Room temperature：30℃ Load ：21.4kN A.P. ：700kPa 100km/h×8h + 60km/h×24h 1set=29,120 km × 6set = 174,720km (with shaving tread rubber)What happens to TB tires due to high heat and pressure ?Profile is changed.!!nullGrowth of Overall Diameter !What happens to TB tires due to high heat and pressure ?nullO.D. growth begins in early stages of tire life. After that , it stabilizes.The growth of tire under operation TB tires have following change under operation.The Growth of Overall Diameter01234567050000100000150000200000mileage ( km )O.D. growth ( mm )TRANSITIONSTABILITYOverall Diameter ( mm )Mileage (km)null Overall Diameter ： Growth O.D. (low pressure) ≒ New tire O.D. ( high pressure) The growth of tire under operation null< The growth of tire under operation. > Outside Diameter ： Growth O.D.(Low Pressure) ≒ New Tire O.D. ( High Pressure) Section Width ： Almost non-changeThe growth of tire under operation nullNEW GROWN--aTire growth Rubber propertiesCalculation of principal strain in tire by FEMRubber propertiesMILEAGE (km)O.D. GROWTH (mm)GROWN--bGROWN--aNEWTB tires have following change under operationEstimation ： Margin of Safety The Growth Of Overall Diameter S - S Curve nullFEM Model ：NEW TIRE1st inflatedProcedure of NEW TIRE simulation NEW TIRE MODEL INFLATED LOADED ANALYSISSIZE：11R22.5RIM：22.5×7.50 A.P 700KPaInflated calculation： 1 timeSimulation of NEW TIRE ( FEM )nullInflated calculation & Inflated calculation ( 2 times ) Double Inflation Pressure Method !2nd-inflatedRIM：22.5×7.50 A.P 700KPa1st-inflated profile =REMODELSimulation of GROWN TIRE ( FEM )Procedure of GROWN TIRE simulation NEW TIRE MODEL INFLATED INFLATED LOADED ANALYSISnullDouble Inflation Pressure MethodCalculated profile corresponds to actual profile.nullAir Pressure vs. Overall DiameternullExample : Effect of tire profile on durability by FEM< NEW TIRE>Estimation ：Principal strain of belt edge fillerLoadedLoadedInflatedNew model Remodel < GROWN TIRE>InflatedDouble Inflation PressurenullExample : Effect of tire profile on durability by FEMOutside surfaceBody ply line SIZE　: 11R22.5nullNew (loaded)Grown (loaded) Contour of strainContact areaExample ： Principal strain of belt edge by FEMnullMargin of Safety = Eb / ε(max)Which is the best ? = “ MODEL B ” New design technology applying simulation approach.Example :Effect of tire profile on durability by FEMnullConclusions1. Double Inflation Pressure Method was developed as prediction of tire profile under operation. 　 2. Safety Factor (Margin of Safety) was introduced,which means not only judging durability by principal strain amount itself,but also applying material property (Eb) of tire. 3. New tire design technology was developed applying the above concept through whole tire life. 4. This simulation approach can be applied to other rubber products.Thank you for your attentions !!Thank you for your attentions !!