Detection Capabilities

Catastrophic mill accidents are frequently caused by subsurface defects in backup rolls and sometimes caused by defects in work rolls. Most subsurface defects are caused by Hertzian contact stress just below the roll surface (resulting in subsurface cracks), inclusions (places from which cracks start to propagate), or debonding (separation of the shell and core in double-poured cast rolls). In all cases, LISMAR’s UT Tester will detect these defects; these defects can only be detected by Ultrasonic technology as none of these defects are on the roll surface.

  • LISMAR’s UT Tester can detect subsurface crack within a range of 2 to 125 mm from the surface.
  • The UT Tester can detect shell-core debonding, internal cracking, mechanical defects, manufacturing defects, and core defects.
  • The UT Tester can detect internal cracks with a more or less parallel orientation to the surface.