Abstract: A pretreating process in powder metallurgy for preparing powders for compacting or densifying operations includes the steps of mixing powder metals with solid lubricants and optionally with liquid solvents to form a mixture and heating the resulted mixture prior to compacting or densifying to a temperature greater than room temperature and below the softening temperature of the solid lubricants.

Abstract: A tool, particularly a nut-cracker, consisting of two twin elements each having at one end a projection shaped as a cylinder sector surrounded by an annular element forming an eyelet and by a circle sector shaped tongue, concentrical with respect to said cylinder sector shaped projection, so as to attain, by inserting said projection of one element into the eyelet formed by the annular portion of the other one element, a tool with two elements or movable hinged arms, with a rotational axis coincident with the geometrical axis of said cylinder sector projections.

Abstract: A press for compressing pulverulent materials into both concave and convex pieces includes a press frame, a die carying plate, upper and lower punches, holders for carrying the punches and control devices for controlling the displacement of the upper and lower punches. The press comprises also a first piston-cylinder device for controlling the displacement of the die carrying plate, a second piston-cylinder device fastened to the frame and supporting the die carrying plate, levers arranged above the die carrying plate and having one end pivoted to the frame and sliders slidable on the opposite ends are provided in the press. The first piston cylinder device acts on the other ends of the levers to exert thereon a pressure depending on the distance of the sliders from the other ends of the levers.

Abstract: A sintered self lubricating bearing comprising at least an area of the inner surface, with a permeability value reduced in respect to that of the remaining mass, the number of reduced permeability areas varying from one to two times the numerical value of the diameter expressed in millimeters.