摘要:
In a method for casting prefabricated products in a continuous casting device, having a casting mold and a strand guide downstream of the casting mold, wherein the strand guide has rolls positioned opposite one another in pairs for supporting and guiding the solidifying cast strand. The motor torques of the drives are maintained at a level as equal as possible below a permissible torque limit value relative to a loadability of the strand shell. For a single drive and corresponding drive roll the permissible torque limit value is measured by continuously increasing the drive torque starting at zero and monitoring the rotational speed of the drive roll, while the remaining drive rolls are controlled to a preset nominal casting speed. For a superproportional increase of the rotational speed, the torque limit value is determined and the process is stopped.
摘要:
A rotating shearing device for cropping fast-running rolling stock, in particular wire, with two axially cutting annular knives which rotate about their axis at the same rotational speed with end cutting edges directed toward one another. The cutting edges converge to the clearance necessary for separating the rolling stock during a cutting operation and lie in planes which are arranged at an acute angle to one another. Rolling stock is guided to the shearing device by a front guide and from the shearing device by a rear guide. The running stock may be guided either through the space between the annular knives which is free for the cut-free passage of the rolling stock or into the wedge-shaped cutting region of the annular knives which is defined by the gripping angle. The front guide is pivotable, the rear guide is fixed and the shearing device is raisable and lowerable in relation to the rear guide.
摘要:
A rotating shearing device for cropping fast-running rolling stock, in particular wire, includes two axially cutting annular knives which rotate about their axes at the same rotational speed. The two axially cutting annular knives include end cutting edges directed toward one another which converge to the clearance required for separating running stock during the cutting operation and lie in planes which are arranged at an acute angle to one another and intersect one another in a line. The rolling stock is guided toward the shearing device by a front guide and guided away from the shearing device by a rear guide. The front guide is pivotable to change in the relative position between the rolling stock and the cutting body so that the rolling stock may be guided either through the space between the annular knives which is free for the cut-free passage of the rolling stock or into the wedge-shaped cutting region of the annular knives. The rear guide part arranged behind the shearing device is also pivotable between a lower end and upper end position.
摘要:
A process for preparing the end of a pipe for drawing over a drawing mandrel, including the following steps: (a) inserting a preforming mandrel into an end of the pipe, the preforming mandrel having a first section having a diameter which is substantially smaller than the inside diameter of the pipe to be drawn, a third section having a diameter which is substantially the same as the inside diameter of the pipe to be drawn, and a second section between the first section and the third section, the second section tapering from the diameter of the third section to the diameter of the first section; (b) rolling the pipe with a set of non-driven rolls while the rolls revolve around the pipe and move axially from the first section of the mandrel to the second section or the mandrel and radially inward to form a constriction in the pipe; (c) rolling the pipe with the rolls while the rolls revolve around the pipe and move axially over the second section of the mandrel toward third section of the preforming mandrel and radially outward so that the pipe has a wall thickness which is continuously reduced as the diameter of the mandrel increases toward the third section; and (d) rolling the pipe with the rolls while the rolls revolve around the pipe and move axially over the third section of the preforming mandrel so that the pipe has a wall thickness which remains constant over the third section to the end of the pipe. The preforming mandrel is than removed so that a drawing mandrel can be inserted and the pipe can be drawn through a drawing mill. Apparatus for practicing the invention is also disclosed.
摘要:
The invention relates to a method for homogenizing a molten metal film, more particularly a steel film, by means of thin strip casting. According to the invention, the melt applied to a rotating strip is of a similar thickness to and possesses the same qualities wherever possible as the width of the strip. In order to homogenize the width of the strip, forces possessing a component perpendicular to the direction of conveyance of the strip are introduced, whereby homogenization of the profile of the molten metal film occurs.