Abstract: A large caliber ring forging apparatus which is able to uniformly forge a ring blank. The apparatus includes a vertical cylinder device (4) adapted such that a vertical ram (4a) thereof is pressurized by a source of pressurization and a horizontal cylinder device (5) adapted such that a horizontal ram (5a) is allowed to execute its forward operation by a pressurized liquid supplied from the vertical cylinder device (4). An anvil (6) is removably secured to the horizontal ram (5a) and to a return cylinder device (7) connected to a hydraulic pressure supply source (8) for returning the anvil 6 to a return position. Disposed in opposition to the anvil is a mandrel (9) used to forge a ring blank (15) and supported by upper and lower tension bars (3, 11). A table roller device (14) supports the ring blank and rotationally drives the ring blank (15).

Abstract: A method and apparatus for measuring the cross-sectional or three-dimensional form of an object using video cameras. The object or the camera means is moved to provide a partial overlap on the measurement object, and local form segments of the object are measured and the segments are connected to synthesize a stereo image of the form of the object, unaffected by fluctuations in the motion of the measurement system.

Abstract: A method for the insulation of a hot metallic material which is heated for hot working is described, which comprises applying a mixture of acidic aluminum phosphate, e.g., aluminum hydrogenorthophosphate, a multivalent metal oxide, hydroxide, silicate or carbonate powder, and water onto the surface of the hot metallic material and allowing the mixture to be heated by the heat of the hot metallic material to convert it to a porous hardened material. The porous hardened material acts as an insulating coating layer for the hot metallic material, permitting hot working in an insulated state for a long period of time.