Reduction of the strip tension of rolling stock between two rolling units to a minimum

Patent metadata

Field	Value
Publication number	US-9694403-B2
Application number	US-201113695391-A
Country	US
Kind code	B2
Filing date	Apr 18, 2011
Priority date	Apr 30, 2010
Publication date	Jul 4, 2017
Grant date	Jul 4, 2017

Abstract

A method for reducing the strip tension of a rolling stock, may include: transporting the rolling stock using a roller table between two successive rolling units, wherein a rolling stock loop is formed in a depression in a section of the roller table between the two rolling units, the rolling stock loop being supported by the roller table at least in one off-center portion of the section, wherein the supporting line of the roller table in this portion corresponds to the catenary curve of the free span; measuring a loop depth of the rolling stock loop; calculating a desired value of the loop depth that corresponds substantially to the free span, e.g., depending on the material, thickness and temperature of the rolling stock; controlling the main drives and/or the gap adjustment of the rolling units based on the desired value and the measured loop depth, such that the loop depth substantially corresponds to the desired value.

First claim

What is claimed is:

1. A method for reducing the strip tension of rolling stock to a minimum, comprising:
using a first roller table, comprising a first plurality of rollers, to transport the rolling stock between two rolling units engaged with the rolling stock,
wherein a rolling stock loop is formed in an entire length of a depression arranged in a section of the first roller table between the two rolling units, the section of the first roller table comprising a second plurality of rollers, the first plurality of rollers comprising the second plurality of rollers, a first end of the depression being located at a first driver roller and a second end of the depression being located at a second driver roller,
wherein the rolling stock loop is supported by the first roller table in at least one portion of the section which does not include the center of the section, and
wherein a supporting line of the rolling stock in the at least one portion is a cross-section of a lower surface of the rolling stock, the supporting line corresponding to a catenary curve of a free span of the rolling stock, the supporting line contacting at least one of the first plurality of rollers;
detecting a measured value of a loop depth of the rolling stock loop using a measuring device;
calculating a desired value of the loop depth such that the desired value corresponds to the free span; and
using a control device to control at least one of: (1) a main drive of the rolling units, (2) a gap adjustment of the rolling units, and (3) at least one of the first driver roller and the second driver roller, based at least on the desired value and the measured value of the loop depth, such that the loop depth corresponds to the desired value,
wherein the second plurality of rollers comprises at least one roller located in a portion of the section which includes the center of the section and which is adjacent to the portion of the section which does not include the center of the section, the second plurality of rollers forming the depression,
the rolling stock loop contacts the second plurality of rollers and has a point on a top surface of the rolling stock at the bottom of the rolling stock loop and the second plurality of rollers are arranged symmetrically with respect to a line which is perpendicular to a tangent to the rolling stock loop, the tangent to the rolling stock loop passing through the point on the top surface of the rolling stock at the bottom of the rolling stock loop, the line which is perpendicular to the tangent to the rolling stock loop passing through the point on the top surface of the rolling stock at the bottom of the rolling stock loop, the rolling stock loop being symmetrical with respect to the line which is perpendicular to the tangent of the rolling stock loop, and
the second plurality of rollers comprises a roller under the bottom of the rolling stock loop.

2. The method of claim 1 , wherein a product of the length of the rolling stock loop, multiplied by the loop depth multiplied by the thickness of the rolling stock is selected to be between 2*10 5 mm 3 and 6*10 7 mm 3 .

3. The method of claim 1 , comprising controlling at least one of the main drive of the rolling units and a driver such that a point on a top surface of the rolling stock at the bottom of the rolling stock loop is held at a distance of between 10 mm and 50 mm from a top of a roller located at a distance from one of the rolling units equal to a distance of a point on a bottom surface of the rolling stock at the bottom of the rolling stock loop from the one of the rolling units.

4. The method of claim 3 , wherein a central axis of each roller in the section is arranged at an equidistant distance from the supporting line of the rolling stock.

5. The method of claim 3 , comprising using a drive apparatus to set the vertical position of at least one roller of the second plurality of rollers with respect to at least one of an entry plane of a second roller table and an exit plane of a last rolling stand of one of the two rolling units.

6. The method of claim 3 , wherein the rolling stock loop is arranged such that a gravitation loop is formed in a central region of the section.

7. The method of claim 1 , comprising measuring a width of the rolling stock metrologically by a measuring device, and transmitting a value of the measured width to the control device by a connection line connecting the measuring device to the control device.

8. The method of claim 7 , comprising using the control device to control the rolling units based on the measured value of the width of the rolling stock and at least one desired value of a gap between the rolling stock and at least one roller in a central region of the section.

9. An apparatus for reducing the strip tension of rolling stock to a minimum, comprising:
a roller table, comprising a first plurality of rollers, configured to transport the rolling stock between two rolling units engaged with the rolling stock;
a control device programmed to control the rolling units such that a rolling stock loop is formed in an entire length of a depression provided in a section of the roller table, the section of the roller table comprising a second plurality of rollers, the first plurality of rollers comprising the second plurality of rollers, a first end of the depression being located at a first driver roller and a second end of the depression being located at a second driver roller, a loop depth of which rolling stock loop being equal to a free span of the rolling stock in the section;
a measuring device configured to measure the loop depth of the rolling stock loop, and transmit the measured value of the loop depth to the control device by a connection line connecting the measuring device to the control device,
the control device being programmed to control at least one of: (1) a main drive of the rolling units, (2) a gap adjustment of the rolling units, and (3) at least one of the first driver roller and the second driver roller, based at least on the measured loop depth of the rolling stock loop,
wherein the roller table forms a support for the rolling stock loop in at least one portion of the section which does not include the center of the section, and wherein a supporting line of the rolling stock in the at least one portion of the section is a cross-section of a lower surface of the rolling stock, the supporting line corresponding to a catenary curve of a free span of the rolling stock, the supporting line contacting at least one of the first plurality of rollers,
the second plurality of rollers comprises at least one roller located in a portion of the section which includes the center of the section and which is adjacent to the portion of the section which does not include the center of the section, the second plurality of rollers forming the depression,
the rolling stock loop contacts the second plurality of rollers and has a point on a top surface of the rolling stock at the bottom of the rolling stock loop and the second plurality of rollers are arranged symmetrically with respect to a line which is perpendicular to a tangent to the rolling stock loop, the tangent to the rolling stock loop passing through the point on the top surface of the rolling stock at the bottom of the rolling stock loop, the line which is perpendicular to the tangent to the rolling stock loop passing through the point on the top surface of the rolling stock at the bottom of the rolling stock loop, the rolling stock loop being symmetrical with respect to the line which is perpendicular to the tangent of the rolling stock loop, and
the second plurality of rollers comprises a roller under the bottom of the rolling stock loop.

10. The apparatus

Assignees

• Eckerstorfer Gerald
• GRüSS ANSGAR
• Schmid Otto
• Primetals Technologies Austria GmbH

Inventors

• Eckerstorfer Gerald
• GRüSS ANSGAR
• Schmid Otto

Classifications

• B21B37/52

  by drive motor control · CPC title

• B21B39/12

  Arrangement or installation of roller tables in relation to a roll stand · CPC title

• B21B39/02

  Feeding or supporting work; Braking or tensioning arrangements {, e.g. threading arrangements} · CPC title

• B21B37/50 Primary

  by looper control · CPC title

• B65H20/34

  with rollers · CPC title