Abstract: Disclosed herein is a water-dispersion-type hot-rolling lubricant for the production of seamless steel pipes. This lubricant features the inclusion of a salt of a polybasic high molecular acid in addition to fine graphite powder, a water-insoluble fine particulate synthetic resin and water as principal components and fine gilsonite powder as an optional component. Even when the surface temperature of a mandrel bar is in a high temperature range of 100.degree.-400.degree. C., this lubricant can form a uniform and thick coating film on the surface of the bar so that the lubricant can exhibit extremely good hot-rolling lubrication performance.

Abstract: A plurality of laser beams emitted from lasers are reflected by mirrors to form a bundle of parallel beams or converged by mirrors into a limited narrow space. Lasers and directing mirrors may be arranged on two or more planes to increase the number of beams per bundle. An ultra-high power, ultra-high density pseudo-single laser beam can be generated by use of one or two groups of reflecting mirrors and a focusing mirror for focusing the beams from the reflecting mirrors into one focal point.

Abstract: A plurality of laser beams emitted from lasers are reflected by mirrors to form a bundle of parallel beams or converged by mirrors into a limited narrow space. Lasers and directing mirrors may be arranged on two or more planes to increase the number of beams per bundle. An ultra-high power, ultra-high density pseudo-single laser beam can be generated by use of one or two groups of reflecting mirrors and a focusing mirror for focusing the beams from the reflecting mirrors into one focal point.

Abstract: A lubricant for the production of seamless tubes comprising water-insoluble fine synthetic resin particles, fine gilsonite and graphite, in which about 30 parts by weight of water-insoluble fine synthetic resin particles, from about 15 to about 30 parts by weight of fine gilsonite particles and from about 40 to about 55 parts by weight of fine graphite powder are contained.

Abstract: An automatic welding apparatus comprising a workpiece fixture carried by a moving member for rotation about a horizontal axis extending in a back and forth direction, said moving member being provided on a carriage for sliding movement in a lateral direction, said carriage being provided for sliding movement in said back and forth direction, and a torch fixture carried by an arm for rotation about a vertical axis, said arm being provided for sliding movement in the vertical direction. In another embodiment, the workpiece fixture is provided only for rotation about a horizontal axis extending in the back and forth direction, and the torch fixture is carried by the arm for rotation about the vertical axis, which arm is provided at the end of a column for sliding movement in said lateral direction, which column is provided on a sliding member for sliding movement in the vertical direction, which sliding member is provided on a guide for sliding movement in said back and forth direction.