FR2699434A1 - Method and device for orienting a magnifying glass before a stretch-reducing mill - Google Patents

Abstract

The present invention relates to a method and a device for orienting a magnifying glass, preferably manufactured by the pusher bed method, before a stretch-reducing rolling mill. - According to the invention, the device comprises a measuring device (2) arranged before the stretch-reducing rolling mill to detect the position of the magnifying glass (1) on the transport roll train, as well as a turning device (5) , associated with the transport roller train, to modify the position of rotation, relative to the longitudinal axis, of the magnifying glass (1) in the determined entry position.

Description

The present invention relates to a method and a device

  for carrying out the method, for orienting a magnifying glass, preferably manufactured by the push-pull method, before a drawing-reducing mill.

  Geometric and dimensional deviations in the circumferential direction of the ideal circular shape for magnifying glasses that are machined into a finished tube in drawing-reduction mills can be found on the finished tube. These defects can be so important that the rolled product

must be eliminated as waste.

  Such geometric and dimensional deviations often occur when a magnifying glass manufactured by the push-bed method is used as the initial tube. This is because, for process reasons, the caliber of the push-bar rig can not be closed, it is created, in the area of jumps caliber, local wall thickening, which cause the magnifying glass leaving the pusher bank has an internal triangular character If we introduce such loupes directly and uncontrollably 20 in a stretch-reduction mill, this triangular character can be further reinforced during the drawing of

  the magnifying glass and cause wall thickness defects so great that they are no longer tolerable, so that the tube or tubes can no longer be used.

  In truth, one can try, by corresponding measurements on the pusher bench installation, for example by modifying

  In addition, it must be ensured that the triangular nature of the internal diameter of the magnifying glass can be compensated for by the adjustment of the cylinders, to compensate for the wall thickness of the magnifying glass on its periphery. does not lead to the scrapping of the tube

  if it can not already be eliminated in the process

preliminary.

  From the known problems and disadvantages of the state of

  The purpose of the present invention is to provide a method and a device for carrying out the method, by which geometrical and

  In the peripheral direction of the magnifying glass can be compensated so that they can no longer be found on the tube leaving the drawing-reduction mill or only to a small tolerable extent.

  For this purpose, the method for orienting a magnifying glass, manufactured

  Preferably, by the push-bed method, before a drawing-reduction mill, it is remarkable, according to the invention, that, before the entry of the magnifier into the pull-down mill, geometric and / or dimensions of the circular form, existing in the peripheral direction

  magnifying glass, are measured and processed into signals, by which the input position of the magnifier in the stretch-reduction mill is determined after adjusting its position.

  rotation with respect to the longitudinal axis.

  The idea of the invention thus consists in that, by posi-

  Depending on the detected peripheral flaw distribution, prior to entry into the first stand of the pull-down mill, it is possible to influence the pull-down mill.

  A device for carrying out this method is characterized by a measuring device arranged before the drawing-reduction mill to detect the position of the magnifier on the transport roll train, as well as by a turning device associated with the feed train. transport rollers, for changing the rotational position, with respect to the longitudinal axis, of the magnifying glass in the position

determined entry.

  For the first time, the position of the size difference of the magnifying glass is detected by a measuring device, between, for example, the reheating furnace arranged downstream of the push-rig plant and the drawing-reduction mill, and the magnifying glass is rotated so that this dimensional difference is in a given position with respect to the stretch-reduction mill This is the condition that, in the stretch-reduction mill, these dimensional differences can be influenced in the sense of The invention thus makes it possible firstly to determine the defect, to detect where the defect is present on the periphery of the magnifying glass, and to turn the magnifying glass so that

  that an appropriate action is possible on the defect.

  Advantageously, the measuring device is a device

  Furthermore, according to another characteristic of the invention, the turning device is formed of transport rollers that can pivot with respect to the longitudinal axis of the magnifying glass.

  According to yet another characteristic of the invention,

  minus the first caliber of the rolls of the rolling mill-

  reducer is calibrated correspondingly to compensate

  dimensional deviations resulting from the preliminary process

  This means that, for example, the first caliber in the caliper bottom makes a larger reduction relative to the periphery of the parts of the magnifying glass which, because of the triangular character of the internal diameter of the magnifying glass, have more wall thicknesses. With the upstream device, the magnifying glass, with these thickened wall parts, can be brought into the

  part of the caliber of the first rolling stand, which acts on these wall parts.

  The particular advantage of the invention is that

  a constructive measure or exchange of preliminary equipment is necessary to produce finished tubes with improved tolerances.

  The single figure of the appended drawing, schematically representing the invention, will make it clear how this

can be realized.

  By reference numeral 1, is designated a magnifying glass which

  left the reheat furnace (not shown) arranged downstream of the push-rig plant and is on the track to the pull-down mill (likewise not shown).

  A multi-channel wall thickness measuring apparatus, generally designated 2, examines the wall of the magnifying glass 1 and determines wall thickness irregularities or also outer diameter deviations from the periphery. The measurement values of the wall thickness measuring apparatus 2 are fed to a control computer 3 which

  provides the measured values, processed in one signal, to a pivot drive 4, which rotates the transport rollers 5 of the transport conveyor roller train.

  with the magnifying glass 1 The transport rollers are, as indicated at 6, rotated and, as indicated at 7, can pivot relative to each other, so that their surfaces resting on the magnifying glass 1 cause a rotation In this way, it is possible to bring the wall thickness irregularities detected by the wall thickness measuring device 2 or the deviations of the wall thickness. external diameter, by pivoting the transport rollers, in a position defined at the periphery of the magnifying glass, to introduce the magnifying lens thus oriented in the drawing-reduction mill, where the differences are machined appropriately by the caliber of the first cage of the rolling mill-reducer. As soon as the lens 1 has reached the determined input position in the stretch-reduction mill, the transport rollers 5, as shown in the lower representation, are pivotally returned to their initial position so that the Magnifying glass is no longer transported

longitudinal direction.

Claims (5)

  1 Method for orienting a magnifying glass, preferably manufactured by the push-pull method, prior to a drawing-ironing mill   gearbox, characterized in that, before the entrance of the magnifier in the drawing-reduction mill, geometric and / or dimensional differences of the circular shape, existing in the direction   The magnifying glass device is measured and processed into signals, whereby the input position of the magnifier in the reduction gear mill is determined after adjustment of its rotational position with respect to the longitudinal axis.   Apparatus for carrying out the method according to claim 1, characterized by a measuring device (2) arranged before the drawing-reduction mill to detect the position of the magnifier (1) on the transport roll train, as well as by a turning device (5) associated with the roller train   transport, to change the position of rotation, relative to the longitudinal axis, of the magnifying glass (1) in the determined input position.   Device according to Claim 2, characterized in that the measuring device (2) is a radiographic apparatus.   4 Device according to Claim 2, characterized in that the measuring device is a device induction measuring electrode.   Device according to one of Claims 2 to 4, characterized in that the turning device (5) consists of   transport rollers pivotable relative to the longitudinal axis of the magnifying glass.   Device according to one of claims 2 to 5,   characterized in that at least the first caliber of the cylinders   of the draw-down mill is calibrated correspondingly to compensate for dimensional deviations   resulting from the preliminary process.