ASTM F1426-20,Standard Practice for Identifying Tire Tread Surface Irregular Wear Patterns Resulting from Tire Use.
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ASTM F1426-20 provides the instructions and nomenclature to evaluate the wear features of the tread pattern on a tire for some intermediate state prior to wear out.
One of the main performance characteristics of tires is the treadlife, defined as the number of kilometers or miles to wear-out, or where the condition of the tread pattern requires the removal of the tire. Before reaching the condition called “wear-out, intermediate conditions of treadwear are frequently encountered, both in tire testing and in normal tire use, that are characterized by complex topological tread pattern features usually called”irregular wear. When irregular wear is present,certain other tire performance features, such as noise and handling, may be affected. Therefore, it isimportant in tire development testing and the assessment of tire use performance to be able to describe accurately the condition of the worn surface of tires.
Over the years, different descriptive names have been given to these worn tread pattern features. a standardized nomenclature system is needed to be able to identify the features that are present and describe the intensity or magnitude of these features. This practice is intended to give sufficient instructions to permit an evaluation of irregular wear. To describe adequately the features of these tread patterns, it is necessary to develop a special logical progressive sequence of definitions or descriptions.