FR2550718A1 - ROLLER FOR THE REDUCTION AND CALIBRATION OF TUBES - Google Patents

Abstract

ROLLING ROLLER FOR THE REDUCTION AND SIZING OF TUBES CONTAINING SEVERAL ROLLING CAGES ARRANGED ONE BEHIND THE OTHERS, IN THE DIRECTION OF THE LAMINATION, IN WHICH TWO CYLINDERS DRAWN IN EACH LAMINATION CAGE AND THE CYLINDERS IN THE CAGES FOLLOWING ONE AGENCIES OFFSET BY 90, ONE IN RELATION TO THE OTHERS, AROUND THE ROLLING AXIS. ACCORDING TO THE INVENTION, THIS LAMINATOR IS REMARKABLE IN THAT, AT THE PERIPHERY OF THE TUBE BETWEEN THE TWO DRIVEN CYLINDERS 1, EACH TIME, A NON DRIVEN CYLINDER 2 IS AGENCY, THE WINDING ANGLE OF THE DRIVEN CYLINDERS 1 IS LARGER THAN THAT OF THE NON-DRIVEN CYLINDERS 2.

Description

The present invention relates to a rolling mill for the sizing and

  reduction of tubes, comprising several rolling stands arranged one behind the other, in which two rolls driven into each rolling stand and the rolls in the stands succeeding each other are arranged offset by 90, relative to one another ,

around the rolling axis.

  DE-PS 366 710 discloses a rolling mill for the reduction of tubes having four rolls driven by a cage.

  one behind the other is turned each time by 45, so that the mark of this space on the rolling stock always rests in the bottom of the caliber of the next cage.

  This leads to a significant and undesirable wear of the caliber In addition, the expensive introduction of the torque and the difficult installation of the cylinders are,

here, disadvantageous.

  In the pipe mill according to DE-PS 675 180, two rolls are provided for each cage, the cylinders of the stands one behind the other being each turned 90 times. The mark of the space between cylinders is also always in the bottom of the caliber of the next cage. This results in a great wear of the cylinders and a relatively defective surface of the tubes. The wear of the cylinders is furthermore reinforced by the high speed.

  relative between the cylinders and the tube.

  The object of the present invention is to provide a rolling mill for the reduction and calibration of tubes, wherein the wear conditions of the gauges are substantially reduced, so that it occurs with respect to the relative velocity between cylinder and tube, rolling conditions 1 similar to those of rolling with a cage-trio; with, however, an introduction of torque and a

  mounting cylinders much simpler.

  To this end, according to the invention, it is provided that at the periphery of the tube between the two driven rolls, each time, a non-driven roll is arranged, the roll angle of the driven rolls being larger than

  that of the untrained cylinders.

  Advantageously, the winding angle of the rolls driven relative to that of the untrained cylinders, is all the greater as the direction of the spaces between the rolls, from the rolling axis, forms an angle

  from about 15 to 350 with the horizontal or the vertical.

  Preferably, in the base of the caliber, the diameter of the driven rolls is greater than that of the rolls

not trained.

  As regards the rolling mill, it is a rolling mill of the universal laminbir type However, deviating from this type, the cylinders forming a template are mounted between two half-plate-shaped cages and the cages housed in addition Many in a frame Each time, two cylinders of a cage are driven The cages are, for this purpose, arranged at a short distance from each other in the direction

rolling.

  From the very beginning of the development of the tube rolling technique, we knew that the forming conditions are all the better as there are more cylinders to form a caliber. But the construction costs, just for the caliber of a rolling mill-trio, were so increased by the use of conical wheels, that all the 1 proposals of more than three cylinders for a caliber, were implemented, in all cases, only for isolated constructions of rolling mills with a particular profile. In the rolling mill according to the invention, no cylinder has a winding angle substantially larger than the rolls of a rolling mill-trio and it follows that the relative velocity between cylinder and tube is not higher. With regard to gauge wear and forming, it is furthermore an advantage that the mark of the space between rolls on the rolling materials does not enter the bottom of the caliber of the rolls of the next roll . The thickness of the wall of the materials to be rolled is for this reason and, because, moreover, the diameter of the non-driven rolls can be chosen different from that of the driven rolls, extraordinarily regular on its periphery. The surface quality of the surface tubes

  laminated on an installation according to the invention is irreproachable.

  With this, the construction costs correspond to those of a rolling mill provided with rolling stands comprising only two cylinders. In this case, it is irrelevant, for the present invention, for the axes of the driven cylinders to be arranged alternately horizontal and

  vertically or cross at 45 to the horizontal.

  The figures of the appended drawings will make it easier to understand

  how the invention can be realized.

  1 shows a view of a rolling stand, in the

  direction of rolling without front plate.

  FIG. 2 is a perspective view of two series of

  cylinders A and B one behind the other.

  Each roll stand of the mill comprises a half-cage 3 in the form of a plate and four rolls, namely two driven rolls 1 and two non-driven rollers 2. The rolls are mounted on both sides in

  the bearings 4 between the half-cages 3.

  The driven cylinders 1 are drawn here with a horizontal axis and they are driven, via a

  gear coupling 5, by a drive not shown.

  Cylinders 1 and 2 form a caliber, the radius of which, with the exception of each time of the last calibration cage, increases slightly from the bottom of caliber 6 to space 7 between cylinders. The winding angle 8 of driven cylinder 1 is larger than that of the cylinders 2 not driven. In the exemplary embodiment shown in FIG. 1, the introduction of the rotational torque occurs in the driven cylinder 1, and this, in the two cylinders from one side of the cage, so that, by this medium, one

  compact construction with easy maintenance, also when changing cage, is possible.

  It is essential for the solution of the problem that the cylinders 1 driven and with them also the cylinders 2 untrained of each following cage are arranged offset by 90, as shown in Figure 2 for cages A and B which follow one another For a better understanding of the position of the cylinders, the cage bodies are not

not represented.

  Thanks to this arrangement and the fact that the winding angles of the driven and non-driven rolls are not the same, the mark corresponding to the space between rolls on the rolling material changes in the succeeding cages. but does not rest in the

  bottom of the caliber of the next cage.

Claims (3)

  Rolling Mill for the Reduction and Calibration of Tubes, having a plurality of rolling stands arranged one behind the other in the rolling direction, in which two rolls driven into each rolling stand and the rolls in the stands succeed one another the others are arranged offset from each other by 900, around the rolling axis, characterized in that, at the periphery of the tube between the two driven rolls (1), a cylinder is arranged each time. not driven (2), the winding angle (8) of the driven cylinders (1) being greater than that of the cylinders (2) not driven.   Rolling mill according to Claim 1, characterized in that the winding angle (8) of the driven cylinders (1), relative to that of the non-driven rolls (2), increases as the direction of the spaces increases. (7) between the rolls, from the rolling axis, forms an angle (9) of about 15 to 350 with horizontal or vertical.   Rolling mill according to Claim 1 or 2,   characterized in that, in the bottom of the caliber, the diameter of the driven rolls (1) is larger than that of the cylinders (2) not driven.