Abstract: A hopper gate and pneumatic actuating mechanism for controlled discharge of bulk materials from a bottom-unloading vehicle are described. The hopper gate comprises an arcuate closure plate pivotally mounted by wedge shaped end plates below a rectangular hopper opening, said hopper opening having one edge defining the end of a hopper end elevated higher than the opposed edge defining the other hopper end wall. The pneumatic actuating mechanism comprises a pair of opposed air bags selectively expanded by an air supply and operatively connected to the closure gate by a linkage system for opening and closing the gate.

Abstract: A method and apparatus for pressure welding together novel aluminum or magnesium workpieces. Edges of workpieces to be pressure welded together are aligned with each other by abutment and one workpiece retracted from the other a predetermined distance to define an open channel between the edges. The workpiece edges are quickly heated to a temperature within the range of from about 200.degree. to 900.degree. F. by passing a uniform flow of heating gases through the channel such that the edge tip and sides of each workpiece are softened while the edge inner cores remain cooler and harder with their mechanical properties unaffected by the heat and the workpieces then moved into abutment with each other to close the channel and immediately pressed together under high pressure for expulsion of softened metal containing deleterious materials such as surface oxides and creation of a solid-phase weld bond between the relatively cool and hard inner cores.

Abstract: A method and apparatus for pressure welding together novel aluminum or magnesium workpieces. Edges of workpieces to be pressure welded together are aligned with each other by abutment and one workpiece retracted from the other a predetermined distance to define an open channel between the edges. The workpiece edges are quickly heated to a temperature within the range of from about 200.degree. to 900.degree. F. by passing a uniform flow of heating gases through the channel such that the edge tip and sides of each workpiece are softened while the edge inner cores remain cooler and harder with their mechanical properties unaffected by the heat and the workpieces then moved into abutment with each other to close the channel and immediately pressed together under high pressure for expulsion of softened metal containing deleterious materials such as surface oxides and creation of a solid-phase weld bond between the relatively cool and hard inner cores.

Abstract: This invention generally relates to a method for butt welding high strength aluminum and magnesium alloys. More particularly this invention pertains to a novel technique for welding (a) high strength aluminum alloys to each other, (b) high strength magnesium alloys to each other, and (c) high strength aluminum alloys to high strength magnesium alloys, under a combination of controlled pressure, temperature and time conditions.