Abstract: A reflowing apparatus for mounting parts on a printed wiring board, has a fixed heating portion for blowing the hot air to the printed wiring board, and a moving heating portion for locally varying the temperature of the hot air blown by the fixed heating portion to the printed wiring board.

Abstract: Sheet bars are effectively joined while they are traveling and subjected to continuous hot rolling without causing defects in quality and without requiring large expensive apparatus such as a swing roller etc.The present invention is to provide a continuous hot rolling method and apparatus in which the tail of a preceding sheet bar is butted to the top of a succeeding sheet bar between the rough and finishing mills on a continuous hot rolling line, and the butted portion is welded from the upper surface of the sheet bars by means of laser beam or plasma arc while the sheet bars are traveling.According to the present invention, it is possible to join sheet bars from the upper surface in a short period of time without stopping the sheet bars and without causing splashes and burrs, before the sheet bars are subjected to continuous finish rolling.

Abstract: Sheet bars are effectively joined while they are traveling and subjected to continuous hot rolling without causing defects in quality and without requiring large expensive apparatus such as a swing roller etc.The present invention is to provide a continuous hot rolling method and apparatus in which the tail of a preceding sheet bar is butted to the top of a succeeding sheet bar between the rough and finishing mills on a continuous hot rolling line, and the butted portion is welded from the upper surface of the sheet bars by means of laser beam or plasma arc while the sheet bars are traveling.According to the present invention, it is possible to join sheet bars from the upper surface in a short period of time without stopping the sheet bars and without causing splashes and burrs, before the sheet bars are subjected to continuous finish rolling.

Abstract: A machine for continuously producing metal tubing from a flat metal strip in which the welder, weld closing rolls, and seam guide are attached to a base plate slidably attached to a support structure. The base plate is displaceable relative to the support structure between an operating position and a start position. The base plate may be displaced by a manually operated actuator or by an electromechanical mechanism. The base plate is placed in the start position when the machine is stopped and is slowly displaced to the operating position when the machine is restarted. During displacement of the base plate to the operation position, the welder overwelds a portion of the seam previously welded. The seam weld during a restart transition of the base plate from the start to the operating position produces a defect-free seam weld.

Abstract: A continuous steel hot-rolling method and apparatus for successively bonding a plurality of steel pieces of a predetermined length and maintained at a high temperature so as to form a continuous train of the steel pieces for roll by a rolling mill. The apparatus includes a holding device for holding a trailing end of a preceding steel piece and a leading end of a succeeding steel piece. A device is provided for shearing the ends of the steel pieces while the ends are held by the holding device. A device heats the sheared trailing end of the preceding steel piece and the sheared leading end of the succeeding steel piece to a predetermined temperature, with a device being provided for driving at least one of the preceding and following steel pieces along a travel path of the steel pieces to press and bond the heated trailing end surface of the preceding steel piece and the heated leading end surface of the succeeding steel piece.

Abstract: A method of and apparatus for continuously hot rolling steel slabs. Separate pieces of steel slabs are continuously fed from a slab yard and delivered to a carriage which is adapted to move reciprocatingly along the line of path of the steel slab pieces. The carriage carries a welder which can move transversely of the path of the slab pieces, and also clamp devices for clamping preceding and succeeding slabs to fix them to the carriage, as means for keeping the preceding and succeeding slab pieces in abutting condition. As a steel strip including a plurality of slab pieces welded together is moved at a predetermined rolling speed into a rolling mill, the carriage moves substantially at the same speed to keep the succeeding slab in abutment with the trailing end of the last slab piece of the steel strip, to permit the welder to weld these slab pieces at their abutting end. This welding is performed only over a part of the cross-sectional area of these slab pieces.

Abstract: A pipe is fabricated from rolls of flat metal plate by continuously moving the plate into a pipe-forming station which shapes the flat plate into a pipe having a longitudinal seam therealong. A plate arc welding machine welds consecutive plates to each other thereby maintaining continuity of plate movement. Equal sections of the longitudinal seam are consecutively welded in a leapfrogging manner using two welding units movably positioned on the opposite sides of the moving pipe. The welding units alternatingly weld alternate and overlapping sections of the longitudinal seam. The welding operations are carried out without interference with the continuous movement of the pipe.