Manufacturing methods and apparatus for targeted lubrication in hot metal rolling

Abstract

Rolling mill apparatus and methods of hot rolling with targeted lubrication are provided herein. A rolling mill apparatus having multiple roll stacks may include a cooling fluid pump and a lubricant pump fluidly coupled with cooling nozzles and lubrication nozzles through a piping system. The piping system may be configured such that the lubricant pump introduces neat lubricant that mixes with the cooling fluid to form a lubricating fluid as loose lubricant emulsion for discharge to select roll stacks through one or more lubrication nozzles, while one or more cooling nozzles discharge the cooling fluid without the added lubricant. The lubrication nozzles may be aimed to target discharge of the lubricant emulsion to the bite roll. Modifications to mill headers to provide targeted lubrication in accordance with the invention are also provided.

What is claimed is: 
     
         1 . A sheet metal rolling apparatus, said apparatus comprising:
 at least one rolling stand having a pair of rolls between which a sheet of metal is rolled to reduce its thickness, wherein the pair of rolls includes a top roll and a bottom roll;   a set of lubricating bite nozzles adapted to discharge a lubricating fluid produced by mixing a cooling fluid with a juice lubricant at an inlet side of each top and bottom roll of the pair of rolls, the set of lubricating bite nozzles comprising one or more lubricating bite nozzles aimed at a roll bite area of the pair of rolls and the sheet of metal;   a set of cooling nozzles adapted to discharge a cooling fluid onto a roll surface of the top roll above the bite spray and discharge the cooling fluid onto a roll surface of the bottom roll below the bite spray, the set of cooling nozzles comprising one or more cooling nozzles;   a cooling fluid pump that pumps the cooling fluid to the one or more cooling nozzles through a piping system;   a lubricant pump that pumps a juice lubricant into the piping system, the piping system being configured such that the juice lubricant mixes with the cooling fluid to form the lubricating fluid before discharge through the one or more lubricating bite nozzles while the cooling fluid flows to the cooling nozzles.   
     
     
         2 . The sheet metal rolling apparatus of  claim 1 , wherein the piping system includes a cooling section and a lubricating section,
 the cooling section fluidly coupling the cooling fluid pump to the cooling nozzles, and   the lubrication section fluidly coupling the lubricant pump and coolant pump to the bite lubrication nozzles.   
     
     
         3 . The sheet metal rolling apparatus of  claim 2 , wherein the lubricating bite nozzles are configured such that fluid discharged therefrom is aimed at a roll bite where the pair of rolls contacts the sheet metal. 
     
     
         4 . The sheet metal rolling apparatus of  claim 2 , wherein the lubrication section includes a static, in-line mixer disposed between the valve and the lubrication nozzles such that the cooling fluid and the lubricant mix within the mixer to form an emulsification of the cooling fluid and the lubricant for discharge through the lubrication nozzles. 
     
     
         5 . The sheet metal rolling apparatus of  claim 1 , further comprising:
 a mill header having a lubrication fluid chamber and a cooling fluid chamber, the chambers being separate, wherein the lubrication fluid chamber is fluidly coupled to the lubrication nozzles and the cooling fluid chamber is fluidly coupled with the cooling nozzles.   
     
     
         6 . The sheet metal rolling apparatus of  claim 1 , wherein the apparatus is adapted for hot rolling of sheet aluminum. 
     
     
         7 . The sheet metal rolling apparatus of  claim 1 , wherein the cooling fluid comprises water or dilute and tight water-in-oil emulsion and the lubricant comprises oil. 
     
     
         8 . The sheet metal rolling apparatus of  claim 1 , wherein the at least one roller stand comprises two or more stands, each having a pair of rolls between which the sheet of metal is rolled to reduce its thickness after being rolled through the first stand of rollers;
 one or more additional sets of lubricating nozzles adapted to discharge a lubricating fluid at an inlet side of the pair of rollers of one or more selected mill stands, each of the one or more additional sets including lubricating nozzles coupled to both the lubricant pump and the cooling fluid pump through the piping system.   
     
     
         9 . The sheet metal rolling apparatus of  claim 1 , wherein the lubricating nozzles deliver bite sprays. 
     
     
         10 . The sheet metal rolling apparatus of  claim 1 , wherein the first set of lubricating nozzles comprise one or more fluid discharge nozzles that direct fluid discharged from the discharge nozzles toward a nipping part of the pair of rollers. 
     
     
         11 . The sheet metal rolling apparatus of  claim 1 , wherein the piping system is configured such that a concentration of the lubricant and cooling fluid discharged from the cooling nozzles is different than that of a concentration of the lubricant and cooling fluid discharged from the set of lubrication bite nozzles. 
     
     
         12 . The sheet metal rolling apparatus of  claim 1 , wherein the piping system is configured such that a composition of the lubricant in the lubricating fluid and of the lubricant in the cooling fluid are different. 
     
     
         13 . The sheet metal rolling apparatus of  claim 1 , wherein the piping, valves and juice lubricant pumping system is configured such that lubricating fluid may contain a different lubricant concentration and composition on each mill stand. 
     
     
         14 . A method of sheet rolling, said method comprising:
 rolling a sheet of metal between a pair of rolls of a metal rolling apparatus; and   lubricating an interface between the metal rolled and each roll of the pair of rolls with a lubrication fluid during rolling, the lubrication fluid comprising a mixture of a cooling fluid and a juice lubricant, the cooling fluid and juice lubricant being pumped into a piping system by a cooling fluid pump and lubrication pump, respectively, and mixed within the piping system before discharged through a set of lubrication bite nozzles.   
     
     
         15 . The method of  claim 14 , further comprising:
 mixing the lubricant and cooling fluid in the piping system within a static mixer to form a loose emulsion of lubricant and cooling fluid.   
     
     
         16 . A method of  claim 14 , said method further comprising:
 rolling the sheet of metal between a pair of rolls of one or more additional stands of the metal rolling apparatus after rolling through the first stand;   lubricating an interface between the metal rolled and each of the pair of rollers of any selected or all mill stands with a lubrication fluid during rolling.   
     
     
         17 . The method of  claim 16  wherein the mixture of lubricant and cooling fluid discharged from the lubrication bite nozzles is the same on each mill stand. 
     
     
         18 . The method of  claim 16  wherein the mixture of lubricant and cooling fluid discharged from the lubrication bite nozzles is different on each mill stand. 
     
     
         19 . The method of  claim 16  wherein the apparatus comprises at least two roll stacks, each comprising a pair of rollers and associated lubrication bite nozzles, wherein the piping includes a static mixer between a juice lubricant source and the lubrication bite nozzles for each roll stack, the method further comprising:
 selectively lubricating a selected roll stack by introducing juice lubricant into the static mixer associated with the lubricant bite nozzles for the selected roll stack. 
 
     
     
         20 . The method of  claim 16  wherein the apparatus comprises at least two roll stacks, each comprising a pair of rollers and an associated set of lubrication nozzles, each set of lubrication nozzles having a header, the method further comprising:
 selectively lubricating a selected roll stack by introducing juice lubricant into the header of the set of lubrication nozzles associated with the selected roll stack.