Abstract: An apparatus and method relating to an improved die for homogeneously stretch forming sheet metal in standard sized presses without also drawing the sheet metal. The die is comprised of complementary male and female die halves moveable between open and closed positions, and a blank holder member moveable between open and closed positions relative to the female die half. A pair of grippers having mutually facing surfaces is carried by the female die half and the blank holder member. One of the gripper surfaces defines exactly two rectangular shaped beads which extend entirely around the circumference of the male and female die halves, while the other of the gripper surfaces is flat. The beads are equally spaced apart along their lengths and each includes a pair of relatively sharp edges for biting into the sheet metal.

Abstract: An apparatus and a process for burnishing annular surfaces. The apparatus includes a burnishing tool which is actuated to rotate in one direction and then in the opposite direction. The apparatus is used for the burnishing of annular thrust bearings which have oil wick slots and wick slot oil ramps. A rack and pinion connects a tool mounting spindle to an air cylinder and is used to rotate the tool in one direction and then the other direction. The tool has a convexly shaped burnishing surface. The tool's axis of rotation is coaxially aligned with the central axis of the annular surface. The rotation of the tool in one direction and then in the other direction burnishes the thrust surface and the wick slot oil ramps of the bearings. The opposite ends of the rotational burnishing strokes locates the tool in the wick slots so as to leave no stopping imperfection on the thrust surface of the bearing.

Abstract: A process and apparatus for making a metal annular member of precise tolerances. The workpiece is formed by welding sheet metal into a tube. The workpiece is presized by expanding it and plastically stretching it into a precise predetermined annular configuration adapted to closely fit a post element having a pair of spaced annular liquid seals mounted thereon. The post element and workpiece are positioned within an annular lower outer die. A cup-shaped upper outer die is placed over the lower die and is used to compress the post element to squeeze the liquid seals to expand them. Forming of the workpiece is accomplished by pumping liquid into the post element between the liquid seals forcing the workpiece to expand against the outer dies and the sheet metal at the end portions of the workpiece to feed into the part being formed from between the outer dies and the post element.