Abstract: A method and apparatus of manufacturing a metal casing, particularly for accessories, such as steel casings, and preferably gate valves which can be employed in installations requiring high safety measures and testing with testing heads, the casings having large nominal widths and particularly usable in nuclear reactors and the like, comprising, permanently deforming a bloom into a tubular body having one open end and an opposite closed end, deforming at least a portion of the tubular body to form at least two diametrically opposed sides thereof which are planar on their interior and exterior surfaces, forming a port in at least one of the planar ends having a diameter less than that of the diametrically opposed sides to leave an approach area around the port and connecting a pipe connection to the port by a single welding seam which can be tested with a testing head which can approach the seam in the approach area. A casing made in accordance with the method is also disclosed.

Abstract: A method of manufacturing metal casings, particularly gate valve casings, comprises, forming two casing shell half portions from a plate by holding the plate and forming a valve port in at least one of the plates with a forming tool, forming wall portions of the plate bounding the port into axially inwardly and axially outwardly extending collars bounding the opening and joining the two casing shell half portions together by a longitudinal weld which is accessible to ultrasonic and radiographic inspection to form a fluid- and pressure-tight casing. A device for carrying out the method comprises forming tools for imparting a shell, shaped to the plates and upper and lower dies which are provided with recesses for holding fast and forming or overforming flange-like collars.

Abstract: A method and apparatus of manufacturing a metal casing, particularly for accessories, such as steel casings, and preferably gate valves which can be employed in installations requiring high safety measures and testing with testing heads, the casings having large nominal widths and particularly usable in nuclear reactors and the like, comprising, permanently deforming a bloom into a tubular body having one open end and an opposite closed end, deforming at least a portion of the tubular body to form at least two diametrically opposed sides thereof which are planar on their interior and exterior surfaces, forming a port in at least one of the planar ends having a diameter less than that of the diametrically opposed sides to leave an approach area around the port and connecting a pipe connection to the port by a single welding seam which can be tested with a testing head which can approach the seam in the approach area. A casing made in accordance with the method is also disclosed.