Title of Invention

ASTCKEL MILL

Abstract (57) Abstract: A Steckel mill ox coiler rolling mill includes at least one reversing stand and drivers and coiler furnaces arranged on the entry side and titer exit side of the reversing stand, wineries the reversing stand, the drivers and the coiler furnaces are connected to one another through roller conveyors for the strip to be rolled At least one heating unit is provided in at least one of the sections formed between the coiler furnaces and the reversing
Full Text



The present invention relates to a Steckel mill or coiler rolling mill with at least one reversing stand and drivers and coiler furnaces arranged on the entry side and the exit side of the reversing stand wherein the reversing stand, the drivers and the coiler furnaces are connected to one another through roller conveyors for the strip to be rolled.
Steckel mills of the adobe-described type have long been known in the art. They operate as follows. The prerolled strip is introduced into the reversing stand under the coiler furnace on the entry side and through the driver on the entry side. After the first pass, the rolling stock is introduced into the coiler furnace on the exit side. After the start of coiling of the strip in the coiler furnace on. the exit side, a predetermined strip tension is applied between the coiler furnace and the reversing stand cud the strip is rolled at the appropriate speed. When the strip end enters the Steckel mill, the plant is decelerated to such an extent that the strip end comes to a standstill behind the roll gap of the

reversing stand but in front of the driver on the exit side. During the reversing operation, the roll gap is adjusted for the next pass. The driver on the exit side introduces the strip into the reversing stand for beginning the next pass. After the beginning of the second pass, the strip is introduced into the coiler furnace on the entry side. At the end of the second pass, the strip beginning comes to a standstill between the driver on the entry side and the reversing stand.
During the reversing operation which, as described above, includes the steps of decelerating the strip, run out of the strip from the coiler furnace, reversing the strip, beginning the next pass and introducing the strip into the coiler furnace, the strip end as well as the strip beginning are cooled to a greater extent as compared to the middle portion of the strip. The increased cooling is caused by the fact that these strip portions are bleatingly not maintained at a high temperature in the coiler furnaces during the reversing operation. At least during the first passes, an additional cooling occurs at the strip beginning and at the strip end when these strip portions are wound onto a cooled mandrel of the coiler furnace which is adjusted to a certain temperature.

Due to the cold portions at the beginning and the end of the strip, the rolling force increases substantially during the pass as compared to the middle portion of the strip. Accordingly, the reversing stand must be designed for the high rolling forces occurring as a result. Because of extreme peaks of the rolling force at the cold portions at the beginning and end of the strip, changes in thickness and/or planeness of the strip can occur over the length of the strip. Accordingly, the rolling stock has a lower quality or relatively large quantities of scrap are produced.

SUMMARY OF THE INVENTION
Therefore, it is the primary object of the present invention to further develop a Steckel mill of the above-described type in such a way that no significant variations in the rolling force occur over the length of the strip, and that the strip is rolled with uniform quality and scrap is avoided.
In accordance with the present invention, at least one heating unit is provided in at least one of the sections formed between the coiler furnaces and the reversing stand, wherein the heating unit covers at least a portion of the respective section.
The solution proposed in accordance with the present invention provides the result that especially that portion of the strip which is not located within the heated coiler furnace can be raised to a temperature corresponding to the temperature of the remaining strip, so that the rolling force is not subject to large variations at least with respect to the temperature pattern over the length of the strip.
In accordance with a further development of the present invention, a heating uppity is provided on each side of the reversing stand, so that not only the temperature of the strip beginning

coming to a standstill in front of the reversing stand can be maintained at the desired level, but also the temperature of the strip end coming to a standstill behind the reversing stand.
As a rule, the drivers on the entry side and the exit side are arranged very closely to the respective coiler furnaces, so that the arrangement of the heating units between the drivers and the reversing stand is completely sufficient.
For quickly and reliquary heating the strip beginning and the strip end, heating units can be provided above the roller conveyors as well as below the roller conveyors. If heating units are provided above and below the roller conveyors, it is advantageous to use the heating units individually as required or to use all heating units together for heating the strip.
The heating processes can be controlled particularly sin5>ly and accurately if, in accordance with either proposal, the heating unit is an induction heating unit.
In accordance with another feature of the present invention, the heating unit includes a control device which is provided with the desired values of the strip temperature and the actual values of the strip temperature. This heating unit has the advantage that

not only the strip beginning and the strip end can be heated as required, but also cold portions within the strip can be recognized and heated if the temperature thereof is below the predetermined desired value of the strip temperature. As is conventional in control technology, it is useful to permit a certain band width of the actual values of the strip temperature, so that the heating unit does continuously switch on and off already at very small strip temperature variations.
In accordance with another feature, a position-dependent heating of the strip, as well as a combination of the control of the heating unit in dependence on the strip position and the strip temperature is possible.
If a switching device is provided which activates only that heating unit which is arranged in the respective strip travel direction in front of the reversing stamd, it is ensured that the strip is appropriately heated prior to the pass in the reversing stem, while the strip emerging from the reversing stand is not subjected to a heating process.
The various features of novelty which characterize the
invention are pointed out with particularity in the claims annexed
to and forming a part of the disclosure. For a better

understanding of the invention, its operating advantages, specific objects attained by its use, reference should be had to the drawing and descriptive matter in which there are illustrated and described preferred embodiments of the invention.
Accordingly, the present invention provides a Steckel mill comprising at least one reversing stand having an entry side and an exit side for strip to be rolled, drivers and coiler furnaces arranged on the entry side and the exit side of the reversing stand, and a roller conveyor for the strip to be rolled for connecting the reversing stand with the drivers and the coiler furnaces, further comprising at least one heating unit in at least one section between the coiler furnaces and the reversing stand, wherein the heating unit covers at least a portion of the section.
With reference to the accompanying drawings in which,
The single figure of the drawing is a schematic sectional view of a Steckel mill according to the present invention.

DESCRIPTION OF THE PREFERRF"
Fig. 1 of the drawing shows a Steckel mill or coiler rolling mill 1. The mill 1 is composed of a Steckel roll stand 2, two drivers 3, 3', two coiler furnaces 4, 4' and a roller conveyor 5 which connects the rollstand 2 to the drivers 3, 3' and the coiler furnaces 4, 4'. A roller conveyor 5' has the purpose of supplying the strip 6 to the rolling mill l and another roller conveyor 5' has the purpose of removing the strip 6 from the rolling mill l.
Heating units 7, 7' and 8, 8' are provided above and below the roller conveyor 5 between the drivers 3, 3'. These heating units 7, 7'; 8, 8' are connected to outputs of a control device 9. The desired value of the strip temperature can be supplied to the control device 9 through the input line 10 from a computer 12 and the desired value of the strip position can be supplied through the input line 11 to the control device 9 from the computer 12. However, these desired values can also be supplied from an input print 15 through input lines 13, 14.
The actual values of the strip temperature are supplied to the control device 9 from the actual value sensors 16, 16' of the strip testator, while the axial values of the strip position can be supplied to the control device 9 through a strip tracking device 17

which receives its various input signals from sensors arranged in the rolling mill at determining positions, not shown.
Accordingly, in dependence on the strip temperature and/or the strip position and/or the strip travel direction, the control device 9 regulates the heating power as required between zero and maximum power.
While specific embodiments of the invention have been shown and described in detail to illustrate the inventive principles, it will be understood that the invention may be embodied otherwise without departing from such principles.




WE CLAIM:
1. A Steckel mill comprising at least one reversing stand having an entry side and an exit side for strip to be rolled, drivers and coiler furnaces arranged on the entry side and the exit side of the reversing stand, and a roller conveyor for the strip to be rolled for connecting the reversing stand with the drivers and the coiler furnaces, further comprising at least one heating unit in at least one section between the coiler furnaces and the reversing stand wherein the heating unit covers at least a portion of the section.
2. The Steckel mill according to claim 1, wherein at least one heating unit each is provided between the two coiler furnaces and the reversing stand.
3. The Steckel mill according to claim 1, wherein the at least one heating unit is arranged between one of the drivers and the reversing stand.
4. The Steckel mill according to claim 1, wherein the at least one heating unit is arranged at least one above and below the roller conveyor.
5. The Steckel mill according to claim 1, wherein the at least one heating unit is an induction heating unit.
6. The Steckel mill according to claim 1, wherein at least one control device is provided for influencing a heating power of the at least one heating unit in

dependence on at least one of a strip temperature and a strip position and a travel direction of the strip.
7. The Steckel mill according to claim 6, wherein actual strip temperature
sensors are provided between the drivers and the reversing stand, a strip
tracking device for the mill, wherein a control device is arranged on the
entry side of the reversing stand as well as on the exit side of the reversing
stand, a computer and an input unit are provided and means for supplying a
desired temperature value of the strip to the control devices from at least one
of the computer and the input unit, and means for supplying at least one of
actual strip temperature values from the actual temperature sensor to the
control devices and strip position values from the tracking device to the
control devices.
8. The Steckel mill according to claim 7, wherein a switching device is
provided for activating the heating device located in front of the reversing
stand in strip travel direction.
9. A Steckel mill substantially as herein described with reference to the
accompanying drawing.


Documents:

467-mas-1996 abstract.pdf

467-mas-1996 claims.pdf

467-mas-1996 correspondence-others.pdf

467-mas-1996 correspondence-po.pdf

467-mas-1996 descirption(complete).pdf

467-mas-1996 drawings.pdf

467-mas-1996 form-2.pdf

467-mas-1996 form-26.pdf

467-mas-1996 form-4.pdf

467-mas-1996 form-6.pdf

467-mas-1996 others.pdf

467-mas-1996 petition.pdf


Patent Number 193847
Indian Patent Application Number 467/MAS/1996
PG Journal Number 20/2006
Publication Date 19-May-2006
Grant Date 05-Dec-2005
Date of Filing 22-Mar-1996
Name of Patentee M/S. SMS SCHLOEMANN-SIEMAG AKTIENGESELLSCHAFT
Applicant Address EDUARD-SCHLOEMANN-STRASSE 4, 40237 DUSSELDORF 1
Inventors:
# Inventor's Name Inventor's Address
1 STEFAN KRAMER INDER MAHLBACH 13, 57271 HILCHENBACH
2 DIETER ROSENTHAL BERGSTRASSE 22A, 57572 NIEDERFISCHBACH
3 PETER SUDAU HUTTENWEG 5, 57271 HILCHENBACH,
PCT International Classification Number B21B41/06
PCT International Application Number N/A
PCT International Filing date
PCT Conventions:
# PCT Application Number Date of Convention Priority Country
1 195 14475.9 1995-04-19 Germany