Steel section rolling mill

Abstract

A section mill (10) for the rolling of steel sections is disclosed. The section mill includes a universal mill stand (12) and an edger mill stand (14) for rolling a workpiece (18) in a plurality of back-and-forth passes into a steel section having a web and one or more flanges. The section mill further includes a cooling arrangement (16) for cooling the workpiece while it undergoes rolling during one or more of the passes. The cooling arrangement includes a cooling box (20) having a spray head (21) with spray openings (22) for spraying jets of pressurized cooling liquid against the workpiece. The cooling arrangement further includes an actuator (38, 34) configured to move the cooling box relative to the stand frame (58) of the universal mill stand and/or of the edger mill stand for adjusting a distance between the spray openings and the workpiece.

Claims

1. A section mill for rolling steel sections, comprising: a universal mill stand; and an edger mill stand for rolling a workpiece in a plurality of back-and-forth passes into a steel section having a web and one or more flanges; each of the universal mill stand and the edger mill stand having a stand frame; a cooling arrangement, mounted to the stand frame of the edger mill stand or the universal mill stand, for cooling the workpiece while the workpiece undergoes rolling during one or more of the passes, the cooling arrangement including a cooling box having a spray head with spray openings for spraying jets of pressurized cooling liquid against the workpiece, the cooling arrangement including an actuator configured to move the cooling box relative to the stand frame of the universal mill stand or of the edger mill stand for adjusting a distance between the spray openings and the workpiece.

2. The section mill as recited in claim 1 further comprising a translation mechanism, the translation mechanism including the actuator.

3. The section mill as recited in claim 2 wherein the translation mechanism constrains a motion of the cooling box to a translation in the plane of the web.

4. The section mill as recited in claim 1 wherein the cooling box of the cooling arrangement is arranged so as to cool the one or more flanges as a whole or locally where joined to the web.

5. The section mill as recited in claim 1 wherein the cooling box is releasably fitted to the actuator, the cooling box including a quick-lock fitting for connecting the cooling box to a cooling liquid supply.

6. The section mill as recited in claim 1 wherein the cooling box includes at least one quick-lock coupler for releasable locking engagement with the actuator.

7. The section mill as recited in claim 1 wherein the cooling arrangement is mounted to the stand frame of the edger mill stand.

8. The section mill as recited in claim 1 wherein the cooling arrangement is mounted to the stand frame of the universal mill stand.

9. The section mill as recited in claim 1 wherein the cooling box is mounted to the stand frame of the universal mill stand or of the edger mill stand, wherein a pusher arranged on the stand frame is used as the actuator and wherein the cooling box is connected to a cooling liquid supply.

10. The section mill as recited in claim 1 wherein the cooling box is mounted to the stand frame in lieu of a flange roll or in lieu of a flange roll chock.

11. The section mill as recited in claim 1 wherein the actuator includes a hydraulic actuator, a pneumatic actuator, an electric actuator or, for manual adjustment of the distance, a mechanical actuator.

12. The section mill as recited in claim 1 wherein the actuator is remotely controllable from a control center.

13. The section mill as recited in claim 1 wherein the section mill is configured for rolling of H-shaped steel sections having the web and two flanges of the at least one flange, and includes a further cooling arrangement, the cooling arrangement and the further cooling arrangement being on each side of the section mill so as to cool the flanges as a whole or locally where the flanges are joined to the web.

14. A cooling box for a cooling arrangement configured to be mounted to a stand frame of an edger mill stand or a universal mill stand of a section mill for rolling steel sections, the edger mill stand being configured for rolling a workpiece in a plurality of back-and-forth passes into a steel section having a web and one or more flanges, wherein the cooling arrangement is mounted to the stand frame of the edger mill stand or the universal mill stand for cooling the workpiece while the workpiece undergoes rolling during one or more of the passes, the cooling box comprising: a spray head with spray openings for spraying jets of pressurized cooling liquid against the workpiece; at least one coupler for releasable locking engagement with an actuator of the cooling arrangement configured to move the cooling box relative to the stand frame of the universal mill stand or of the edger mill stand for adjusting a distance between the spray openings and the workpiece; and a fitting for connecting the cooling box to a cooling liquid supply.

15. The cooling box as recited in claim 14 wherein the at least one coupler includes a quick-lock coupler or wherein the fitting is a quick-lock fitting.

16. The cooling box as recited in claim 14 wherein the spray head is removable.

17. The cooling box as recited in claim 14 further comprising at least one mount on an upper side of the cooling box for supporting a horizontal roll chock.

18. The cooling box as recited in claim 14 wherein the cooling box is configured to be stackable between a lower horizontal roll chock and an upper horizontal roll chock.

19. A method of retrofitting a section mill with a cooling arrangement, wherein the section mill is configured for the rolling of steel sections and comprises a universal mill stand and an edger mill stand for rolling a workpiece in a plurality of back-and-forth passes into a steel section having a web and one or more flanges, each of the universal mill stand and the edger mill stand having a stand frame, the method comprising: providing a cooling box comprising a spray head with spray openings for spraying jets of pressurized cooling liquid against the workpiece; mounting the cooling box to the universal mill stand or the edger mill stand in lieu of a flange roll and fitting the cooling box to a pusher arranged on the stand frame; connecting the cooling box to a cooling liquid supply; and using the pusher as an actuator for moving the cooling box relative to the stand frame of the universal mill stand or of the edger mill stand for adjusting a distance between the spray openings and the workpiece.

20. The method as recited in claim 19 wherein, prior to mounting the cooling box to the universal mill stand or the edger mill stand in lieu of the flange roll, the flange roll is removed from the stand frame together with a roll chock of the flange roll and wherein the cooling box is mounted on the stand frame in lieu of the roll chock.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) The accompanying drawings illustrate several aspects of the present invention and, together with the detailed description, serve to explain the principles thereof. In the drawings:

(2) FIG. 1: is a schematic perspective view of a rolling mill according to an embodiment of the invention;

(3) FIG. 2: is a perspective view of a cooling box as it may be positioned relative to the edger rolls of an edger mill stand;

(4) FIG. 3: is a schematic cross-sectional view of the cooling box of FIG. 2 mounted in a mill stand;

(5) FIG. 4: is a schematic view of the edger mill stand in the rolling direction;

(6) FIG. 5: is the view of FIG. 4, wherein only one flange roll and its chock have been replaced by a cooling box;

(7) FIG. 6: is a schematic view of a cooling arrangement having a higher spray head for cooling substantially the whole flange of the workpiece;

(8) FIG. 7: is a side view of a trolley for the replacement of the rolls of a mill stand, carrying a stack of rolls, wherein cooling boxes take the positions that are conventionally those of the flange rolls in their chocks.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS

(9) FIG. 1 schematically shows a section mill 10 rolling steel sections. Section mill 10 comprises a universal mill stand 12 and an edger mill stand 14. The edger mill stand 14 is equipped with cooling arrangements 16 for locally cooling the workpiece 18 while it is rolled. (Only one of the cooling arrangements is visible in FIG. 1, the other one is hidden by the workpiece 18.) The workpiece 18 (beam blank) is rolled into its final shape in a plurality of back-and-forth passes. In the illustrations, the workpiece 18 has an H-shaped cross-section with a web and two flanges.

(10) Details of a preferred embodiment of the cooling arrangements are best contemplated with reference to FIGS. 2-5. Each cooling arrangement 16 comprises a cooling box 20 having a spray head 21 (see, e.g., FIG. 3) with spray openings 22 for spraying jets of pressurized cooling liquid 24 against the workpiece 18. FIG. 2 illustrates how the cooling box 20 is positioned relative to the edger rolls 26 of the edger mill stand 14. (The workpiece and details of the edger mill stand are not shown for the sake of clarity.) The cooling box 20 comprises a removable spray head 21 extending in the rolling direction of the section mill 10. The spray openings 22 are disposed in the spray head 21. In operation, the spray head 21 is arranged with the spray openings 22 facing the outward-oriented face of one of the flanges of the workpiece 18. The spray head 21 lies substantially in the plane of the web of the workpiece 18, so that the jets of the cooling liquid 24 are projected against the joint area between the web and the flange (best shown in FIG. 4).

(11) The cooling box 20 shown in FIGS. 2-5 is configured for replacing a flange roll 30 and its roll chock 32 on a mill stand. FIG. 5 schematically illustrates an edger mill stand 14, wherein one of the flange rolls 30 and the corresponding roll chock 32 are in place, whereas the others have been replaced by a cooling box 20. FIG. 4 shows the same edger mill stand, wherein both flange rolls and their roll chocks have been replaced by cooling boxes 20.

(12) As indicated before, it is particularly advantageous to mount the cooling box 20 in lieu of a flange roll and the corresponding roll chock because the loading cylinders 34 can readily be used for positioning the cooling box 20 relative to the stand frame and thus to the workpiece. Furthermore, the cooling liquid supply provided for the cooling of the flange roll can serve to supply the cooling liquid to the cooling box 20.

(13) As best shown in FIG. 3, the cooling box 20 comprises a support body 36, which is dimensioned so as to fit within the space otherwise occupied by the flange roll 30 and its chock 32. The spray head 21 with the spray openings 22 is mounted on the support body 36. The support body comprises a quick-lock coupling arrangement that is of the same type as that of the roll chock 32. In the illustrated embodiment, the hydraulic actuators comprise a centrally arranged balancing cylinder 38, the piston 40 of which terminates in a catch 42, and two laterally arranged loading cylinders 34. The support body 36 comprises a central coupler 46 for receiving the catch 42 and interlocking with it (e.g. by rotation of the catch 42 about the piston axis). The balancing cylinder 38 exerts a pulling force 48 on the support body 36, so as to hold the cooling box 20 in place against the loading cylinders 34. The loading cylinders 34 push against the support body 36 at abutments 50. The loading cylinders 34 are controlled in such a way as to maintain the cooling box 20 in a certain position relative to the stand frame 58 and thus to the workpiece 18. To this end, the loading cylinders 34 comprise position sensors measuring the positions of the pistons. A controller (not shown) then regulates the hydraulic pressure of the loading cylinders 34 in such a way that their pistons stay at the desired position. The balancing cylinder 38 applies a force 48 in the direction opposite to that of the forces 52 induced by the loading cylinders 34, so as to maintain the cooling box 20 permanently in contact with the loading cylinders 34.

(14) The support body 36 also comprises a quick-lock fitting 55 (See, e.g., FIG. 5) for connecting the manifold 54 of the cooling box with the cooling liquid supply 56 of the mill stand via a coolant conduit 44.

(15) The spray head 21 is removably attached to the support body 36 by means of screws, bolts, clamps, or the like (not shown). The joint between the manifold 54 and the coolant conduit 44 is made fluid-tight by a face-seal gasket 45.

(16) As shown in FIG. 4, the mill stand 14 comprises a first and a second cooling arrangement 16 of the described type, for locally cooling the first and the second flange of the workpiece, respectively. FIG. 6 shows a variant of the cooling arrangements of FIG. 4, wherein the spray head 21 is configured for cooling substantially the entire outward face of the flange of the workpiece 18.

(17) The cooling arrangements 16 are particularly useful for retrofitting a rolling mill, as the only necessary additional components are the cooling boxes configured in such a way that they can be mounted on a mill stand in lieu of a roll or of a roll in its chock. It should be noted that although in the preferred embodiment described above the cooling arrangements are mounted on an edger mill stand, they could also be mounted on a universal mill stand. Furthermore, while a solution wherein each cooling box replaces a roll within its chock is certainly preferable, a solution wherein the roll chock remains in place and only the roll is replaced by the cooling box could also be envisaged.

(18) FIG. 7 illustrates a trolley 60 for the replacement of the rolls and chocks of a universal or edger mill. In the illustrated case, cooling boxes 20 are stacked in-between the lower 62 and upper 64 horizontal rolls in their respective chocks 66a, 66b and 68a, 68b, taking the place of the flange rolls and the corresponding chocks. To place the components on the trolley 60 into the mill stand, the latter is opened and the trolley 60 is introduced into the stand. The rolls mounted in their chocks and the cooling boxes 20 are then lifted from the trolley 60 and brought into position in the stand. Finally, the trolley 60 is driven out of the stand or remains therein. To remove the rolls and the cooling boxes 20 from the stand, the trolley is introduced, when necessary, and the procedure is carried out in the reverse order.

(19) The cooling boxes 20 are configured stackable with the lower 62 and upper 64 horizontal rolls in their respective chocks 66a, 66b and 68a, 68b. Specifically, the cooling boxes 20 are configured such that their relevant dimensions and the load bearing capacity correspond to those of the flange roll chocks that are replaced. In the illustrated case, the cooling boxes 20 comprise mounts 70 (see also FIG. 2) arranged on their upper sides for supporting the chocks 68a, 68b of the upper horizontal roll 64.

(20) While specific embodiments have been described herein in detail, those skilled in the art will appreciate that various modifications and alternatives to those details could be developed in light of the overall teachings of the disclosure. Accordingly, the particular arrangements disclosed are meant to be illustrative only and not limiting as to the scope of the invention, which is to be given the full breadth of the appended claims and any and all equivalents thereof.