Patent CZ-304119-B6 (CZ)
Title: Method for producing gilled metal pipes, device for implementing the method and gilled metal pipe produced by this method
Inventor: BRUENDERMANN GEORG
IPC: B23K9/032
Filed: 2001-01-19
Abstract: The present invention relates to a method for producing gilled metal pipes, particularly heat exchanger pipes, where at least one continuous, gill-forming strip (4) is applied to a rotating pipe (1) body (2) at a tangent and wound onto the pipe (1) body (2) in an approximately helical line, the side of the strip facing the pipe body is connected to the pipe surface by means of an electric welding device using an additional material, and the working end of the welding device is guided in the open wedge between the pipe surface and the winding strip, characterized in that a web (6) is bent at roughly right angles on the strip (4) that forms the gills before said strip is wound onto the pipe body (2), in that the web (6) is guided flat on the pipe body (2) during winding of the strip (4) onto the pipe body (2), while the leg positioned roughly at a right angle thereto forms the gills, in that welding is carried out in the region of the open wedge between the pipe body surface (3) and the contact surface (10) of the web (6) facing the pipe body surface, in that both the surface (3) of the pipe body (2) and the contact surface (10) of the web (6) to be welded to it are fused during the welding process, and in that the weld (5) produced using the additional material is narrower than the width of the web (6). The method is further characterized in that the strip (4) forming the gills is bent into U-shape prior to winding onto the pipe body (2), and in that the roughly flat U-web (6) between the U-legs (7) is guided flat on the pipe body (2), while the two U-legs (7) positioned roughly at a right angle thereto form the gills and further in that the contact surface (10) of the web (6) is profiled prior to welding and further in that with the help of the welding device and using the additional material, a welding bead is applied to the pipe surface (3) precisely in the connecting area between the web (6) and the pipe (1) body (2) surface, before the web (6) to be welded contacts it, and in that the web (6) is pressed into the still-molten welding bead. A device for implementing the above-described method comprises a chucking device (11) for clamping the pipe body (2) to be wrapped, a drive unit for the chucking device (11) to turn the pipe body (2) about its longitudinal axis, and a support for accommodating a strip supply roll and an electric welding device (8), where the pipe (1) body (2) and the support can move relative to one another in the direction of the longitudinal axis of the pipe (1) body (2). The support is provided with at least one pressure roller (13) that is positioned immediately behind the welding area, contacts the rear side of the web (6) facing away from the contact surface (10), and presses the web (6) against the pipe body surface (3) after completion of the welding process. The device further comprises a coaxial guide roller (14), which contacts the surface of the leg (7) of the strip (4) facing away from the pressure roller (13), wherein the leg (7) is guided between the pressure roller (13) and the guide roller (14). A gilled metal pipe produced in the above-indicated manner, particularly a heat exchanger pipe, comprises a cylindrical pipe body (2) and a strip (4) wound onto it in a helical line, which strip (4) is connected to the pipe surface by means of a weld produced by an electric welding device using an additional material. The strip (4) is provided with a web (6) running parallel to the pipe body (2) surface, wherein the contact surface (10) of the web (6) is welded to the pipe body (2) surface (3), and the weld (5), consisting of additional material, is narrower than the width of the web (6).