SPECTRAL SIGNATURES OF STICKER WRENCH FAULTS IN TEMPER ROLLING OF BATCH ANNEALED STEEL STRIP

This paper reports an investigation into the occurrence of an acoustic signature which anecdotal evidence had suggested was indicative of th e rupture of localised bonds in annealed coils of steel during rolling . These are the cause of surface defects referred to by their formatio n mechanism as sticker wrench marks. It is demonstrated that the acous tic radiation exhibits a characteristic spectral signature, with a ban d of energy typically concentrated in the region of 14-17 kHz. The aut hors' explanation of the physics of generation of the acoustic radiati on is supported by photographic evidence of the wrench marks.