Method and apparatus for lubricating glass molds

Abstract

A smokeless lubricant for coating the interior surfaces of glass forming molds to protect them during contact with molten glass and to facilitate release of formed glass products, including an inert fluid carrying medium, a thermally inert chemical compound suspended in this medium and a wetting agent which causes the chemical compound to adhere to molecules of the fluid carrying medium. The method of lubricating glass forming molds with such a lubricant by mixing selected amounts of the chemical compound and wetting agent in the fluid carrying medium to form the lubricant, stirring or agitating this mixture to maintain the compound in suspension within the carrying medium, and flash-heating this lubricant to a temperature sufficient to vaporize the carrying medium and cause the chemical compound to be exploded onto the interior surfaces of the mold to coat these surfaces. An apparatus to perform the above method in timed relationship to the delivery of a charge of molten glass to the molds, having a metering means to assure that an optimum amount of chemical compound is delivered to the carrying medium, a mixer to maintain the chemical compound in suspension within the medium, delivery conduit means to transfer the lubricating mixture to the molds, injecting means to meter a desired amount of lubricant toward the molds, and a heating chamber to flash-heat the lubricant to a temperature sufficient to vaporize the carrying medium and explode the suspended chemical compound with the vapor onto the interior surfaces of the molds.