Abstract: According to the invention, the rear end of a preceding metal piece and a front end of a succeeding metal piece are heated, pressed and joined prior to the finishing hot rolling. An alternating magnetic field running through the metal pieces in the thickness direction thereof is generated in an end region on opposed faces of the respective metal pieces to perform heating. Another alternating magnetic field whose direction is reverse with respect to that of the former alternating magnetic field is partially generated in the end region on the opposed faces of the metal pieces and in either a region where the metal pieces exist or a region outside width ends of the metal pieces. This assures a uniform heating of the end region on the opposed faces of the metal pieces over their full width to reliably join the both metal pieces to each other.

Abstract: A method and apparatus for joining metal pieces wherein the rear end of a preceding metal piece and a front end of a metal piece are heated and then pressed together prior to hot finished rolling. The temperature the ends of the metal pieces are heated to is a temperature range between the solidus and liquidus line temperatures of the metal(s) to be joined.

Abstract: According to the invention, the rear end of a preceding metal piece and a front end of a succeeding metal piece are heated, pressed and joined prior to the finishing hot rolling. An alternating magnetic field running through the metal pieces in the thickness direction thereof is generated in an end region on opposed faces of the respective metal pieces to perform heating. Another alternating magnetic field whose direction is reverse with respect to that of the former alternating magnetic field is partially generated in the end region on the opposed faces of the metal pieces and in either a region where the metal pieces exist or a region outside width ends of the metal pieces. This assures a uniform heating of the end region on the opposed faces of the metal pieces over their full width to reliably join the both metal pieces to each other.

Abstract: Method and apparatus for joining metal pieces using induction heating. Metal pieces to be joined are placed end-to-end with a gap between them and induction heated in the thickness portion. To maximize speed and even heating edge-to-edge of the ends, members of a magnetic substance are provided in a gap between the inductor and the piece to be heated, thereby enhancing local heating effect by increasing magnetic flux density. Once heated, the ends are pressed together end-to-end for joining.

Abstract: An apparatus for joining metal pieces using induction heating. Preceding and succeeding metal pieces are followed by a carriage which carries an inductor. The inductor has the ability to move in the longitudinal direction of the metal pieces relative to the carriage to allow the inductor to move more or less upon the preceding or succeeding metal pieces to increase or decrease the induction heating effect, thereby taking into account any thickness variation of the metal pieces and yet still heating them evenly with regard to each other, prior to their being pressed against each other for joining before hot finishing rolling.

Abstract: According to the invention, the rear end of a preceding metal piece and a front end of a succeeding metal piece are heated, pressed and joined prior to the finishing hot rolling. An alternating magnetic field running through the metal pieces in the thickness direction thereof is generated in an end region on opposed faces of the respective metal pieces to perform heating. Another alternating magnetic field whose direction is reverse with respect to that of the former alternating magnetic field is partially generated in the end region on the opposed faces of the metal pieces and in either a region where the metal pieces exist or a region outside width ends of the metal pieces. This assures a uniform heating of the end region on the opposed faces of the metal pieces over their full width to reliably join the both metal pieces to each other.

Abstract: A sheet crown control method and apparatus for use in endless rolling in which consecutively fed sheets are joined to each other to be continuously rolled through a rolling equipment line. The rolling equipment line includes a junction device for joining consecutively fed sheets to each other, a plurality of stands arranged in tandem on the downstream side of the junction device and having a roll bender load adjusting mechanism and a roll crossing mechanism. The roll cross angle of rolls incorporated in a stand of each rolling mill is set at a predetermined value beforehand if there is a roll cross angle that will enable a target sheet crown to be applied to each sheet and the roll bender load of each stand is adjusted on-line, thereby effecting sheet crown control. Rolling also may be performed while adjusting the roll cross angle of rolls incorporated in stands of each rolling mill on-line together with the roll bender load.

Abstract: In this invention, a back end portion of a preceding sheet bar and a front end of a succeeding sheet bar are cut in a transfer line at an entrance side of a finish rolling mill so that at least both side edge regions of these sheet bars are contacted with each other at a butted contact state thereof and a gap is formed between both end portions and then portions to be joined int he preceding and succeeding sheet bars are locally heated and pushed to join them while gradually enlarging a joining area, whereby the required time is largely reduced as compared with the conventional technique and also it is attempted to miniaturize the heating apparatus and shorten the length of the apparatus.

Abstract: In the continuously hot rolling of plural sheet bars, in order to simply and surely join the sheet bars to the back end portion of the preceding sheet bar and the front end portion of the succeeding sheet bar are prejoined by butting to each other at an entrance side of a finish rolling mill and then bitten into the finish rolling mill, during which the joining of the sheet bars are promoted to conduct the continuous rolling.

Abstract: A method of continuously hot-rolling sheet bars in which a roughly rolled leading sheet bar and a trailing sheet bar are abutted prior to a hot finish rolling step. Plastic deformation of either or both of the cut rear and front end portions of the leading and trailing sheet bars is applied. End portions are brought into contact with each other due to metal flow, forming a gap portion between the sheet bars. The thickness of the sheet bar around the gap portion is enlarged in comparison to the thickness of the contact portions, and hot finish rolling fills the gap so that the bars are strongly joined over their width.

Abstract: A method for preventing the camber of a two-layered clad metal sheet having a base layer and a covering layer of different metals which exhibit different amounts of thermal contraction. The method comprises developing a temperature difference .DELTA. T expressed by the following formula between the base layer and the covering layer during a hot levelling, by providing a greater cooling effect before or during levelling to the layer which exhibits the greater thermal contraction than to the layer which exhibits the smaller thermal contraction:.DELTA.T=f (.DELTA..alpha., .alpha., a, To)where,.DELTA..alpha.: the difference in thermal expansion coefficient between both metalsa: the clad ratio (ratio of covering layer thickness to total sheet thickness)To: hot leveller inlet temperature (.degree.C.).alpha.: mean thermal expansion coefficient of both metals.

Abstract: A heat exchanger adapted for use as a hot water radiator for a car heater, or the like, in which a plurality of tubes and a plurality of fins secured thereon extend between two fluid tanks. The fluid tanks each comprise an inner and an outer tank element, both made of synthetic resin. The inner tank element is joined via gaskets with the end portions of the tubes extending therethrough, by means of tube-expansion working, while the outer tank element is united with the inner tank element along corresponding opposed peripheral edges thereof arranged in abutting relation. A pair of partition walls are provided in opposed relation between the inner and outer tank elements, which are joined together in an abutting manner directly or via part of the gasket, to provide a fluid tight partition between an inlet chamber and an outlet chamber defined by the partition walls and the tank elements.