Accession Number : ADA335220

Title :   System for Non-Destructive Testing of Tire Sidewalls

Descriptive Note : Final rept.

Corporate Author : ETASYS INC FORT COLLINS CO

Personal Author(s) : Downs, Justin, III

PDF Url : ADA335220

Report Date : 31 OCT 1997

Pagination or Media Count : 29

Abstract : Tire inspection has previously used x ray, shearography, and low resolution ultrasound to inspect portions of a tire but not the entire tire Dow97. Recently Reis demonstrated acousto-ultrasonic inspection to detect belt damage in steel-belted radial tire sidewalls Rei97. Each technique is noted for its ability to detect certain types of problems within the rubber composite material of the tire in specific locations without providing a scan of the entire tire. Ultrasound in particular has been shown to be capable of detecting disbond and material property changes within the material Rog92. Specifically, the acoustic impedance of the material is altered in locations with disbond and/or material property changes. The change in acoustic impedance can be used to detect tire flaws using high resolution 2-D scanning to locate areas with acoustic impedance changes. Material property changes are often associated with heat damage to the material. Heat can cause additional crosslinking between long-chain molecules within material and change the acoustic properties. Heat can also cause a reduction in crosslinking known as reversion that also changes the acoustic properties of the material Fre89. Disbond affects the acoustic impedance of the material by reflecting a part of the ultrasound beam. Recent advances in data-acquisition and control technology have allowed large data-set, high speed inspection systems to be produced. The use of inexpensive PC (Personal Computer) based data acquisition, control, signal-processing and display enables a cost- effective tire scanning system. Before developing a complex inspection system for aircraft tires, the ability to detect material property changes in aircraft tires is demonstrated.

Descriptors :   *NONDESTRUCTIVE TESTING, *ULTRASONICS, *RADIAL TIRES, CONTROL, POSITION(LOCATION), DAMAGE, MOLECULES, COMPOSITE MATERIALS, RUBBER, X RAYS, STEEL, COSTS, DEFECTS(MATERIALS), CHAINS, INSPECTION, DATA ACQUISITION, MICROCOMPUTERS, HEAT, LOW RESOLUTION, ACOUSTIC PROPERTIES, ACOUSTIC IMPEDANCE, AIRCRAFT TIRES, SCANNERS.

Subject Categories : Surface Transportation and Equipment
      Acoustics

Distribution Statement : APPROVED FOR PUBLIC RELEASE