Patent ID: 8192561

Claim:
A method for manufacturing at least one part of a hydraulically operated tilt rotator ( 22 ) or rotator ( 26 ) configured for mounting directly or indirectly on an arm ( 12 ) of an earth-moving or material-handling machine, the tilt rotator ( 22 ) or rotator ( 26 ) having been arranged to enable at least one of coupling, linear displacing or positioning by tilting or turning of a tool ( 14 ), and at least one surface ( 29 ) of said at least one part of the tilt rotator ( 22 ) or rotator ( 26 ) is arranged to make tribological contact with another component in the tilt rotator ( 22 ) or the rotator ( 26 ) or with a mating surface of said tool, when the tilt rotator ( 22 ) or rotator ( 26 ) is in use, the method comprising: a) forming a melt comprising unalloyed or alloyed ductile iron; b) casting at least one part of the tilt rotator ( 22 ) or the rotator ( 26 ) from said melt; c) allowing said at least one part of the tilt rotator ( 22 ) or the rotator ( 26 ) to cool; d) austenizing said at least one part of the tilt rotator ( 22 ) or the rotator ( 26 ); e) quenching said at least one part of the tilt rotator ( 22 ) or the rotator ( 26 ) to an austempering temperature; f) austempering said at least one part of the tilt rotator ( 22 ) or the rotator ( 26 ), thereby allowing complete isothermal transformation to ausferrite; and g) allowing said at least one part of the tilt rotator ( 22 ) or the rotator ( 26 ) to cool, wherein the surface material ( 29 ) of said at least one part undergoes a transformation to martensite when said at least one part of the tilt rotator ( 22 ) or the rotator ( 26 ) is subjected to a high contact force during use, thus forming and subsequently regenerating a wear resistant surface to avoid adhesive wear and seizure.