Abstract: This invention concerns a process of welding by an electron beam. The process is one in which the beam is rapidly deflected from point to point of a predetermined matrix of spots over which the beam rests for predetermined lengths of time in order to produce a predetermined distribution of energy over a defined area along the surface of the material being welded along a seam formed at the adjacent edges of workpieces. The length of time the beam is maintained at each position and the total beam power may be varied from spot to spot in order to produce a desired distribution of energy over a given area. This process is useful to avoid defects in partial penetration welds and in the welding of joints in which the gap between the edges to be welded may approach the diameter of the electron beam. The method is also useful in avoiding defects which may normally occur at the beginning and end of a weld seam.

Abstract: A vacuum sealing means for a high production electron beam welding machine incorporating a rotary indexing table carrying parts to be welded from a loading position to a welding position under a stationery electron beam gun and then to an unloading station. Sealable pockets on the rotating index table carrying the parts to be welded are carried through a sealed off low volume space into a first pre-pumping station where air in the pocket is brought to a pressure intermediate between the atmospheric pressure and the pressure required during the welding of the parts. After pre-pumping, the pockets are indexed to a second pumped area where the pocket is evacuated to the pressure suitable for welding. The table is then indexed through an area at the pre-pumping pressure and then through another sealed off space at atmospheric pressure to the ejection station.

Abstract: A method and apparatus for the manufacture of rotary drill bits such as are used for oil well drilling which are constructed from a multiplicity of segments. The segments are provided with registration means for positioning the segments relative to one another and are placed in a fixture where they are sized to a desired outer diameter without sliding the faces of the segment one against the other during the sizing operation. The faces are then brought into abutment, clamped and welded along the abutting surfaces between segments.

Abstract: This invention is for a method for controlling the motion of an electron beam gun with respect to a workpiece so that the electron beam will follow the path along the seam between the two parts which are to be welded. The electron beam scans the seam in a circular motion. The center of the circle is offset a distance equal to the radius of the circle ahead of the resting position of the electron beam in the direction of travel, by applying the signals R (sin .omega.t + sin .theta.) and R (cos .omega.t + .theta.) to deflection coils which deflect the beam along two mutually perpendicular axes whose origin is at the resting position of the beam. Control of the motion of the electron beam gun with respect to the workpiece is achieved from signals derived as the seam is scanned by the circular motion of the electron beam in the area including the seam. The signals are in the form of pulses generated by the reduction in secondary and reflected electrons as the electron beam traverses the seam.