GB1393143A - Method of lubricating a billet during extrusion - Google Patents

Abstract

1393143 Extruding BATTELLE MEMORIAL INSTITUTE 4 Aug 1972 [16 Aug 1971] 36533/72 Heading B3P A billet 10 is extruded by precoating it with a solid lubricating material 23, providing between the coated billet 10 and the extrusion container 20 a lubricating liquid film 22 having a thickness less than 1% of the billet diameter when the diameter is 1 inch or more or less than 0À010 inch when the diameter is less than 1 inch and advancing a ram 30 into the container 20 to pressurize the liquid material 22 and to force the billet 10 through the die 21. A seal 31 is positioned on the ram 30 or on a dummy block contacting the billet 10. The liquid may also be provided between the ram 30 and billet 10. The extrudate may be a tube. In one embodiment, the wall of the container 20 is coated with a solid lubricant and a heated, precoated billet 10 inserted into the container 20 to cause the lubricant coating the container 20 to melt and form a liquid lubricant film 22. In another embodiment, a precoated billet 10 is inserted in the container 20 which is heated by heating elements 40 causing a portion of the billet coating contacting the container 20 to melt and form the liquid film 22. The solid layer of lubricant 23 may comprise copper plating, zinc phosphate and stearate soap, fluoroplastics hydrogenated castor oil, grease, wax or ice. The liquid layer of lubricant 22 may comprise, petroleum or vegetable oil, synthetic fluid, water, grease or wax.