Core for coiled sheet metal, manufacturing method, and method for packaging coils

Abstract

A hollow cylindrical core ( 1 ), e.g. paperboard core, for coiled sheet metal ( 5 ), the core ( 1 ) being made from at least one ply of material wound into the shape of a tube, the core having an outer circumferential surface ( 2 ), an inner circumferential surface ( 3 ) and a cavity ( 4 ) inside the core ( 1 ) which is defined by the inner circumferential surface ( 3 ), and the core ( 1 ) being open at least at one end, wherein the core ( 1 ) is provided with a volatile corrosion inhibitor inside the cavity ( 4 ).

What is claimed is: 
     
         1 . A hollow cylindrical core for coiled sheet metal, the core being made from at least one ply of material wound into the shape of a tube,
 the core having an outer circumferential surface, an inner circumferential surface and a cavity inside the core which is defined by the inner circumferential surface, and the core being open at least at one end,   wherein the core is provided with a volatile corrosion inhibiting (VCI) composition inside the cavity.   
     
     
         2 . The hollow cylindrical core according to  claim 1 , wherein the outer circumferential surface of the core is left free of any volatile corrosion inhibiting (VCI) composition. 
     
     
         3 . The hollow cylindrical core according to  claim 1 , wherein the core is provided with a volatile corrosion inhibiting (VCI) composition also on the outer circumferential surface of the core. 
     
     
         4 . The hollow cylindrical core according to any one of  claims 1 - 3 , in which the VCI composition is provided as a coating on, or an impregnation into, the material forming the inner and/or outer circumferential surface of the core. 
     
     
         5 . The hollow cylindrical core of any one of the preceding claims, in which the VCI composition is provided as a coating on, or an impregnation into, an additional material layer inserted into the cavity within the core. 
     
     
         6 . The hollow cylindrical core of any one of the preceding claims, comprising a plurality of material plies wound into a tube. 
     
     
         7 . The hollow cylindrical core of  claim 6 , wherein the material plies are adhesively bonded to each other. 
     
     
         8 . The hollow cylindrical core of any one of the preceding claims, in which at least one ply of material is a paperboard ply. 
     
     
         9 . The hollow cylindrical core of any one of the preceding claims, further comprising sheet metal wound around the outer circumference of the core so as to form a metal roll or coil. 
     
     
         10 . The hollow cylindrical core of  claim 9 , further including an end header at least at one longitudinal end of the metal roll or coil, wherein the end header is preferably also provided with a volatile corrosion inhibitor. 
     
     
         11 . The hollow cylindrical core of  claim 9  or  10 , further including a packaging material wrapped around the metal roll or coil so as to enclose the metal roll or coil and the volatile corrosion inhibiting (VCI) composition in a substantially closed airspace. 
     
     
         12 . A method of manufacturing a hollow cylindrical core for coiled sheet metal, the method comprising the steps of:
 winding at least one ply of material into the shape of a tube so as to obtain a core having an outer circumferential surface, an inner circumferential surface and a cavity inside the core which is defined by the inner circumferential surface, the core being open at least at one end, and   providing a volatile corrosion inhibiting (VCI) composition inside the cavity.   
     
     
         13 . The method of  claim 12 , wherein the outer circumferential surface of the core is left free of any volatile corrosion inhibiting (VCI) composition. 
     
     
         14 . The method of  claim 12 , wherein the core is provided with a volatile corrosion inhibiting (VCI) composition also on the outer circumferential surface thereof. 
     
     
         15 . The method according to any one of  claims 12  to  14 , in which the VCI composition is coated onto, or impregnated into, the material forming the inner and/or outer circumferential surface of the core. 
     
     
         16 . The method of any one of  claims 12  to  15 , in which at least one ply of the material is coated or impregnated with the VCI composition before the ply or plies of material are wound into the shape of a tube. 
     
     
         17 . The method of claim any one of  claims 12  to  16 , in which at least one ply of the material is coated or impregnated with the VCI composition while the ply or plies of material are wound into the shape of a tube. 
     
     
         18 . The method of any one of  claims 12  to  17 , in which the material forming the inner and/or outer circumferential surface of the core is coated or impregnated with the VCI composition after winding the ply or plies of material into the shape of a tube. 
     
     
         19 . The method of any one of  claims 12  to  18 , in which the VCI composition is coated onto, or impregnated into, an additional material layer and the additional material layer is inserted into the cavity inside the core. 
     
     
         20 . The method of any one of  claims 12  to  19 , wherein the material plies are adhesively bonded to each other. 
     
     
         21 . The method of any one of  claims 12  to  20 , wherein at least one ply of material is a paperboard ply. 
     
     
         22 . A method of packaging a coiled metal sheet for storage or transport, comprising the steps of:
 placing a volatile corrosion inhibiting (VCI) composition inside the coiled metal sheet, and   wrapping the coiled metal sheet in a packaging material so as to enclose the coiled metal sheet and the volatile corrosion inhibiting (VCI) composition in a substantially closed airspace.   
     
     
         23 . The method of  claim 22 , further comprising the step of providing a core according to any one of  claims 1  to  8  inside the coiled metal sheet, or winding a metal sheet about a core according to any one of  claims 1  to  8 . 
     
     
         24 . The method of  claim 22  or  23 , wherein the packaging material also includes a volatile corrosion inhibiting (VCI) composition. 
     
     
         25 . The method of any one of  claims 22  to  24 , wherein the packaging material is wrapped around the metal coil sufficiently loosely so as to allow for a circulation of air from the inside of the core towards the metal coil surfaces to be protected from corrosion. 
     
     
         26 . The method of any one of  claims 22  to  25 , wherein an end header is provided on at least on one of the open ends of the coiled metal sheet within the sealed airspace of the packaging material, wherein the end header is preferably also provided with a volatile corrosion inhibiting (VCI) composition. 
     
     
         27 . Use of a hollow cylindrical core according to any one of  claims 1  to  8 , or a hollow cylindrical core manufactured in a method according to any one of  claims 12  to  21 , for winding sheet metal.