GB1559672A - Roller tables for furnaces - Google Patents

Description

(54) IMPROVEMENTS IN ROLLER TABLES FOR FURNACES (71) We, DAVY-LOEWY LIMITED, a British company of Prince of Wales Road, Sheffield S9 4EX, Yorkshire, do hereby declare the invention, for which we pray that a patent may be granted to us, and the method by which it is to be performed, to be particularly described in and by the following statement: This invention relates to furnaces which have a roller table therein on which the articles to be heated are supported as they are passed through the furnace. A particular application of the invention is in the heating of metal strip between successive passes of the strip through a Steckel mill.

In furnaces of this type provision is taken to ensure that the rollers and their bearings and the drive for the rollers are suitably protected from the hot environment in which they find themselves in the furnace. In spite of this the rollers, the bearings and the drive have to be replaced from time to time and difficulties can occur in removing the roller easily and readily from the furnace.

According to the present invention, a roller table comprises a plurality of parallel spaced apart rollers each rotatable in support bearings, the bearings for each roller being mounted on a carriage which is displaceable in the direction of the length of-the roller on rails extending into a furnace whereby the rollers are displaceable into and out of the furnace.

Preferably the drive for each roller is mounted on the same carriage as the roller.

In this way the roller table is withdrawn as a unit from the furnace for maintenance purposes and either the same unit can be pushed back after maintenance or a replacement set can be returned to the furnace structure.

In order that the invention may be more readily understood it will now be described, by way of example only, with reference to the drawings filed with the Provisional Specification, in which : - Figure 1 is a diagrammatic view showing the invention applied to a Steckel mill, Figure 2 is a side elevation partly in section of a roller table in a furnace structure, and Figure 3 is a section on the line Ill-Ill of Figure 2.

Referring to Figure 1, a Steckel rolling mill 2 has a pair of work rolls 4 each supported by a back-up roll 6. On each side of the mill there is a furnace 8, 10. Within the furnace 8 there is a metal strip coiler 12 and within the furnace 10 there is a strip coiler 13. An entry roller table 14 consisting of a plurality of driven rollers 15 serves to convey strip from a primary furnace (not shown) to the mill. The entry table extends through the structure of the furnace 8. Similarly on the exit side of the mill 2 there is a roller table 16 which serves to convey the strip from the mill, an the completion of rolling, to a down coiler (not shown). The exit roller table 16 passes through the structure of the furnace 10. Pinch roll units 18, 20 are positioned on the ingoing and outgoing side of the mill respectively.A ramp 19 is provided between the pinch roll unit 18 and the coiler 12 and a similar ramp 21 is positioned between pinch roll unit 20 and its associated coiler 13. The ramps 19, 21 are arranged to be raised in order to direct the leading end of the strip into the appropriate coiler drum.

In use, a metal strip is fed from a primary furnace along the entry roller table 14 beneath the coiler 12 in the furnace 8, between the pinch rolls 18 and then between the work rolls 4 of the mill where the strip is reduced in thickness. The strip passes from the mill between the pinch rolls 20 and along the raised ramp 21 and into the coiler drum 13. When the strip is being coiled by the coiler 13 the pinch roll unit 20 is open so that the strip can pass freely therethrough.

To avoid a need for reheating the strip between rolling operations the coiler 13 is mounted within the furnace 10 and the coiler is maintained at a temperature of around 1000 C.

After the entire strip has passed through the mill 2, the mill and the coiler 13 are stopped, the pinch roll unit 20 is closed with the trailing end of the strip arrested somewhere between the mill roll bite and the pinch rolls 20. The roll gap is then at rusted and the direction of rotation of the rolls is reversed so that the strip is then passed back through the mill to be reduced further and then re-coiled on coiler 12 in the furnace 8. Again the coiler 12 is maintained at a temperature of around 1000"C in the furnace structure.

The forward and reverse passage of the strip is repeated with an adjustment to the roll gap of each passage until the thickness of the strip is as required. The strip is then passed out of the mill, being propelled by the pinch rolls 20, along the exit roller table 16 to the down coiler.

Because the strip is coiled within the furnace structures 8 and 10 the temperature of the strip is maintained at the required level for reduction rolling. The temperature of the furnace is however detrimental to the components of the roller tables which are within the furnaces and these components need frequent replacement and maintenance despite the fact that the rollers and their bearings are water cooled.

Referring to Figures 2 and 3, parallel, spaced apart rollers 14A, 14B and 14C forming part of the entry table 14 are shown within the furnace structure. These rollers and their bearings 32 with their drive motors 30 are mounted on a carriage 24 which is slidable on rails 26 set in the foundations 28. Cables 34, 36 are connected to the opposite ends of the carriage 24 and by hauling on the appropriate cables the carriage with the rollers, their bearings and their drive motors can be hauled into and out of the working position in the furnace structure 8. The rollers 14A, 14B, 14C are displaced in the direction parallel to their longitudinal axes.

The rollers of the exit table 16 which are within the furnace structure 10 are mounted in an identiacal manner to those described above with respect to the furnace structure 8.

WHAT WE CLAIM IS:- 1. A roller table comprising a plurality of parallel spaced apart rollers each rotatable in support bearings, the bearings for each roller being mounted on a carriage which is displaceable in the direction of the length of the roller on rails extending into a furnace whereby the rollers are displaceable into and out of the furnace.

2. A roller table as claimed in claim 1, in which each roller has an electric drive motor connected to one end thereof and the drive motor is mounted on the same carriage as the bearings for the roller.

3. A roller table as claimed in claim 1 or 2, in which the bearings for a plurality of rollers are mounted on the same carriage.

4. A roller table as claimed in claim 1, 2 or 3, in which the or each carriage has a pair of cables connected thereto one at each of the opposite ends of the rollers whereby the carriage can be displaced into and out of the furnace by hauling on the appropriate cable.

5. The combination of a roller table and a furnace substantially as hereinbefore described with reference to the drawings filed with the Provisional Specification.

**WARNING** end of DESC field may overlap start of CLMS **.

Claims (5)

**WARNING** start of CLMS field may overlap end of DESC **. with the trailing end of the strip arrested somewhere between the mill roll bite and the pinch rolls 20. The roll gap is then at rusted and the direction of rotation of the rolls is reversed so that the strip is then passed back through the mill to be reduced further and then re-coiled on coiler 12 in the furnace 8. Again the coiler 12 is maintained at a temperature of around 1000"C in the furnace structure. The forward and reverse passage of the strip is repeated with an adjustment to the roll gap of each passage until the thickness of the strip is as required. The strip is then passed out of the mill, being propelled by the pinch rolls 20, along the exit roller table 16 to the down coiler. Because the strip is coiled within the furnace structures 8 and 10 the temperature of the strip is maintained at the required level for reduction rolling. The temperature of the furnace is however detrimental to the components of the roller tables which are within the furnaces and these components need frequent replacement and maintenance despite the fact that the rollers and their bearings are water cooled. Referring to Figures 2 and 3, parallel, spaced apart rollers 14A, 14B and 14C forming part of the entry table 14 are shown within the furnace structure. These rollers and their bearings 32 with their drive motors 30 are mounted on a carriage 24 which is slidable on rails 26 set in the foundations 28. Cables 34, 36 are connected to the opposite ends of the carriage 24 and by hauling on the appropriate cables the carriage with the rollers, their bearings and their drive motors can be hauled into and out of the working position in the furnace structure 8. The rollers 14A, 14B, 14C are displaced in the direction parallel to their longitudinal axes. The rollers of the exit table 16 which are within the furnace structure 10 are mounted in an identiacal manner to those described above with respect to the furnace structure 8. WHAT WE CLAIM IS:-

1. A roller table comprising a plurality of parallel spaced apart rollers each rotatable in support bearings, the bearings for each roller being mounted on a carriage which is displaceable in the direction of the length of the roller on rails extending into a furnace whereby the rollers are displaceable into and out of the furnace.

2. A roller table as claimed in claim 1, in which each roller has an electric drive motor connected to one end thereof and the drive motor is mounted on the same carriage as the bearings for the roller.

3. A roller table as claimed in claim 1 or 2, in which the bearings for a plurality of rollers are mounted on the same carriage.

4. A roller table as claimed in claim 1, 2 or 3, in which the or each carriage has a pair of cables connected thereto one at each of the opposite ends of the rollers whereby the carriage can be displaced into and out of the furnace by hauling on the appropriate cable.

5. The combination of a roller table and a furnace substantially as hereinbefore described with reference to the drawings filed with the Provisional Specification.