Simulation Study On Giant Radial Tire Vulcanization Process

The process of curing a pneumatic tire as the one of most important working procedure in the manufacturing process, directly determines the quality of the tire. In condition of a certain pressure and temperature, the tire rubber crosslinking reaction occurs, and obtains the using performance. The physical and mechanical properties of rubber in the state of overcure or undercure are significantly decreased. So ensuring that tire constituents achieved the proper state of cure (SOC) can improve the quality of tire. Giant radial tires are large, and the large difference is in the thickness, so the state of rubbers also have large difference and difficult to achieve the proper SOC. This dissertation modeled the tire with aid FEA modelization, according to the actual tire vulcanization process, evaluated overall SOC of giant radial tire, which is agrees well with the experimental test. In order to reduce the difference of SOC of tire constituents, we changed the curing time and curing temperature, made most of tire constituents achieve the proper SOC by changing the formula.A new method named Departure of Torque (DOT) for quantifying SOC is presented. DOT comes from the rheometer torque, based on the rubber's shear modulus of the variation to quantify the SOC, can accurately reflect the SOC of rubber component, and brings convenient to optimize the process conditions of vulcanization. The FEA model of vulcanization includes tire, mold and bladder. Tires are made of various kinds of rubber and steel cord composite, so all the parts of the materials were defined the different thermal properties. The result shows good agreement with test data, and the DOT accurately reflects the SOC of rubber component. The purpose of this study is to acquire a more uniform SOC for all zones of the tire and a reduced cure time. In practice and FEA analysis, the only change of the process conditions is difficult to make all parts of plastic materials are in condition. Another way to optimize is to change the rubber formula. The vulcanization curve obtained by FEA analysis is able to provide the reference to the formula designer.This study will promote FEA in the application for deciding the process condition, put forward a simple and effective way, make contributions to improve the quality of tires, conserve energy, reduce costs and increase efficiency.