【国外标准】 Standard Test Methods for Single-Filament Tire Bead Wire Made from Steel (Withdrawn 2023)

5.1 The procedures for the determination of properties of single-filament bead wire made from steel are considered satisfactory for acceptance testing of commercial shipments of this product because the procedures are the best available and have been used extensively in the trade.5.1.1 In case of a dispute arising from differences in reported test results when using these test methods for acceptance testing of commercial shipments, the purchaser and supplier should conduct comparative test to determine if there is a statistical bias between their laboratories. Competent statistical assistance is recommended for the investigation of bias. As a minimum, the two parties should take a group of test specimens which are as homogeneous as possible and which are from a lot of material of the type in question. The test specimens then should be randomly assigned in equal number to each laboratory for testing. The average results from the two laboratories should be compared using Student's t-test for unpaired data and an acceptable probability level chosen by the two parties before testing is begun. If a bias is found, either its cause must be determined and corrected or the purchaser and the supplier must agree to interpret future test results with consideration to the known bias.1.1 These test methods cover testing of single-filament steel wires that are components of tire beads used in the manufacture of pneumatic tires. By agreement, these test methods may be applied to similar filaments used for reinforcing other rubber products.1.2 These test methods describe test procedures only and do not establish specifications and tolerances.1.3 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.1.4 These test methods cover the determination of the mechanical properties listed below:  Property   Section   Breaking Force (Strength)  7 – 13  Yield Strength  7 – 13  Elongation  7 – 13  Torsion Resistance 14 – 20  Diameter (Gage) 21 – 271.5 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.