Instrumentation Technique for Measuring Bead Stresses in Tires

A method has been developed to measure strain in individual wire strands of bead bundles. The method was used to investigate stresses to which the bead wires are subjected during tire molding. Test results showed that during molding, the majority of strands are in compression. Maximum compressive stresses encountered were 140 lbs. Applications of the method to other problems, such as bead stresses during mounting operations are discussed.