Multi-roll table ring-rolling mill as well as method for rolling rings in a multi-roll table ring-rolling mill

Abstract

In a multi-roll table ring-rolling mill and method, a mandrel roll can be switched from a rolling state into a free-running state, when a predetermined ring diameter is reached, even if the roll gap minimum has not yet been reached, in order to improve the size accuracy of the rolled rings. A mandrel roll table rotating about a mandrel table axle is used, along with at least one main roll rotating about a main roll axle and first and second mandrel rolls that are mounted in the mandrel roll table, and a relief device to relieve at least the first mandrel roll of rolling forces. The main roll axle and the mandrel roll table axle are mounted in unchangeable manner and eccentric to one another, at least during the rolling process. The relief device acts independent of the main roll axle and the mandrel roll table axle are eccentric to one another.

Claims

1. A multi-roll table ring-rolling mill comprising: (a) a mandrel roll table rotating about a mandrel table axle; (b) at least one main roll rotating about a main roll axle and first and second mandrel rolls mounted in the mandrel roll table; and (c) a relief device for relieving at least the first mandrel roll of rolling forces; wherein the main roll axle and the mandrel roll table axle are mounted in unchangeable manner and eccentric to one another at least during a rolling process; wherein the relief device acts independent of the main roll axle and the mandrel roll table axle being eccentric to one another; and wherein the relief device comprises a releasable mandrel roll lock of the first mandrel roll on the mandrel roll table, the releasable mandrel roll lock comprising a snap connection or other engagement device.

2. The multi-roll table ring-rolling mill according to claim 1, further comprising a measurement device for measuring a ring diameter of a ring situated and rolled between the first mandrel roll and the main roll or between the second mandrel roll and the main roll.

3. The multi-roll table ring-rolling mill according to claim 2, wherein the measurement device is connected to act together with the relief device in such a manner that the relief device relieves the first mandrel roll when a specific ring diameter has been reached.

4. The multi-roll table ring-rolling mill according to claim 2, wherein the measurement device is disposed on the mandrel roll table.

5. The multi-roll table ring-rolling mill according to claim 1, further comprising a return device for returning the first mandrel roll from a release position to a rolling position.

6. The multi-roll table ring-rolling mill according to claim 1, further comprising a first measurement device for the first mandrel roll and a second measurement device for the second mandrel roll, wherein the first measurement device measures a ring diameter of a first ring situated and rolled between the first mandrel roll and the main roll and the second measurement device measures a ring diameter of a second ring situated and rolled between the second mandrel roll and the main roll.

7. A rolling method for rolling rings in a multi-roll table ring-rolling mill comprising a mandrel roll table rotating about a mandrel table axle; at least one main roll rotating about a main roll axle and first and second mandrel rolls mounted in the mandrel roll table; and a relief device for relieving at least the first mandrel roll of rolling forces; wherein the main roll axle and the mandrel roll table axle are mounted in unchangeable manner and eccentric to one another at least during a rolling process; wherein the relief device acts independent of the main roll axle and the mandrel roll table axle being eccentric to one another; and wherein the relief device comprises a releasable mandrel roll lock of the first mandrel roll on the mandrel roll table, the releasable mandrel roll lock comprising a snap connection or other engagement device, the rolling method comprising: (a) rotating the first and second mandrel rolls mounted in the mandrel roll table about the main roll to form a first gap between the first mandrel roll and the main roll and a second gap between the second mandrel roll and the main roll; (b) reducing to a roll gap minimum each of the first and second gaps as a function of an angular position of the mandrel roll table existing with reference to the main roll; (c) subsequently increasing the first and second gaps; and (d) when a first predetermined ring diameter is reached for the first mandrel roll, switching the first mandrel roll from a rolling state into a free-running state and when a second predetermined ring diameter is reached for the second mandrel roll, switching the second mandrel roll from a rolling state into a free-running state, wherein the switching takes place even if the roll gap minimum has not yet been reached.

8. The rolling method according to claim 7, wherein to switch the first mandrel roll from the rolling state into the free-running state, the first roll gap of the first mandrel roll is opened.

9. The rolling method according to claim 7, wherein to switch the first mandrel roll from the rolling state into the free-running state, the first roll gap of the first mandrel roll is relieved of rolling force.

10. The rolling method according to claim 7, wherein to switch the first mandrel roll from the rolling state into the free-running state, the first roll gap of the first mandrel roll is opened and the first mandrel roll is relieved of rolling force.

11. The rolling method according to claim 7, wherein after the first or second mandrel roll was switched into the free-running state, the mandrel roll is switched back into the rolling state before commencement of a subsequent rolling process with the first and second mandrel roll, respectively.

12. The rolling method according to claim 7, wherein to switch the first and second mandrel roll from the rolling state into the free-running state, the respective mandrel roll is displaced, with reference to the mandrel roll table, from a rolling position into a release position that is farther away from the main roll than the rolling position.

13. The rolling method according claim 12, wherein after displacement of the first and second mandrel roll from the rolling position into the release position, and before the commencement of the subsequent rolling process with the first and second mandrel roll, respectively, the mandrel roll is displaced back into the rolling position.

14. A multi-roll table ring-rolling mill comprising: (a) a mandrel roll table rotating about a mandrel table axle; (b) at least one main roll rotating about a main roll axle and first and second mandrel rolls mounted in the mandrel roll table; and (c) a relief device for relieving at least the first mandrel roll of rolling forces; wherein the main roll axle and the mandrel roll table axle are mounted in unchangeable manner and eccentric to one another at least during a rolling process; wherein the relief device acts independent of the main roll axle and the mandrel roll table axle being eccentric to one another; wherein the relief device comprises a displacement device for displacing a mounting of the first mandrel roll on the mandrel roll table; and wherein the displacement device comprises a motor-driven eccentric device and the first mandrel roll is mounted on the motor-driven eccentric device.

15. The multi-roll table ring-rolling mill according to claim 14, further comprising a measurement device for measuring a ring diameter of a ring situated and rolled between the first mandrel roll and the main roll or between the second mandrel roll and the main roll.

16. The multi-roll table ring-rolling mill according to claim 15, wherein the measurement device is connected to act together with the relief device in such a manner that the relief device relieves the first mandrel roll when a specific ring diameter has been reached.

17. The multi-roll table ring-rolling mill according to claim 15, wherein the measurement device is disposed on the mandrel roll table.

18. The multi-roll table ring-rolling mill according to claim 14, further comprising a return device for returning the first mandrel roll from a release position to a rolling position.

19. The multi-roll table ring-rolling mill according to claim 14, further comprising a first measurement device for the first mandrel roll and a second measurement device for the second mandrel roll, wherein the first measurement device measures a ring diameter of a first ring situated and rolled between the first mandrel roll and the main roll and the second measurement device measures a ring diameter of a second ring situated and rolled between the second mandrel roll and the main roll.

20. A rolling method for rolling rings in a multi-roll table ring-rolling mill comprising a mandrel roll table rotating about a mandrel table axle; at least one main roll rotating about a main roll axle and first and second mandrel rolls mounted in the mandrel roll table; and a relief device for relieving at least the first mandrel roll of rolling forces; wherein the main roll axle and the mandrel roll table axle are mounted in unchangeable manner and eccentric to one another at least during a rolling process; wherein the relief device acts independent of the main roll axle and the mandrel roll table axle being eccentric to one another; wherein the relief device comprises a displacement device for displacing a mounting of the first mandrel roll on the mandrel roll table; and wherein the displacement device comprises a motor-driven eccentric device and the first mandrel roll is mounted on the motor-driven eccentric device, the rolling method comprising: (a) rotating the first and second mandrel rolls mounted in the mandrel roll table about the main roll to form a first gap between the first mandrel roll and the main roll and a second gap between the second mandrel roll and the main roll; (b) reducing to a roll gap minimum each of the first and second gaps as a function of an angular position of the mandrel roll table existing with reference to the main roll; (c) subsequently increasing the first and second gaps; and (d) when a first predetermined ring diameter is reached for the first mandrel roll, switching the first mandrel roll from a rolling state into a free-running state and when a second predetermined ring diameter is reached for the second mandrel roll, switching the second mandrel roll from a rolling state into a free-running state, wherein the switching takes place even if the roll gap minimum has not yet been reached.

21. The rolling method according to claim 20, wherein to switch the first mandrel roll from the rolling state into the free-running state, the first roll gap of the first mandrel roll is opened.

22. The rolling method according to claim 20, wherein to switch the first mandrel roll from the rolling state into the free-running state, the first roll gap of the first mandrel roll is relieved of rolling force.

23. The rolling method according to claim 20, wherein to switch the first mandrel roll from the rolling state into the free-running state, the first roll gap of the first mandrel roll is opened and the first mandrel roll is relieved of rolling force.

24. The rolling method according to claim 20, wherein after the first or second mandrel roll was switched into the free-running state, the mandrel roll is switched back into the rolling state before commencement of a subsequent rolling process with the first and second mandrel roll, respectively.

25. The rolling method according to claim 20, wherein to switch the first and second mandrel roll from the rolling state into the free-running state, the respective mandrel roll is displaced, with reference to the mandrel roll table, from a rolling position into a release position that is farther away from the main roll than the rolling position.

26. The rolling method according claim 25, wherein after displacement of the first and second mandrel roll from the rolling position into the release position, and before the commencement of the subsequent rolling process, with the first and second mandrel roll, respectively, the mandrel roll is displaced back into the rolling position.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) Further advantages, goals, and properties of the present invention will be explained using the following description of exemplary embodiments, which are particularly also shown in the attached drawing. The drawing shows:

(2) FIG. 1. is a schematic top view of a multi-roll table ring-rolling mill;

(3) FIG. 2 is a multi-roll table ring-rolling mill according to FIG. 1, with relief of a mandrel roll having taken place;

(4) FIG. 3. is a schematic top view of a multi-roll table ring-rolling mill with a mandrel roll lock and the mandrel roll guided in an oblong hole and locked by the mandrel roll lock in all steps; and

(5) FIG. 4 is a multi-roll table ring-rolling mill according to FIG. 3, with the mandrel roll unlocked by the mandrel lock in steps B and C.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS

(6) The multi-roll table ring-rolling mill 10 shown in the figures comprises, centrally, a main roll 20 that rotates about a main roll axle 26, as well as four mandrel rolls 30, which are mounted on a mandrel roll table 35, which in turn rotates about a mandrel roll table axle 36.

(7) In this connection, the main roll axle 26 and the mandrel roll table axle 36 are offset from one another, so that in this way, an eccentric arrangement of these two axles and of the main roll 20 and of the mandrel roll table 35 is brought about. The corresponding direction of rotation 27 of the main roll 20 about the main roll axle 26 and the direction of rotation 37 of the mandrel roll table 35 or of the mandrel rolls 30 about the mandrel roll table axle 36 are indicated with arrows, in each instance.

(8) The mandrel rolls 30 are mounted on the mandrel roll table 35 with an identical distance from the mandrel roll table axle 36, as such, so that a roll gap 16 between the respective mandrel roll 30 and the main roll 20 periodically changes between a roll gap maximum and a roll gap minimum, as a function of the angular position of the mandrel roll table 35 with reference to the mandrel roll table axle 36 or the main roll 20.

(9) Furthermore, relief means 40 are provided on the mandrel roll table 35 for each mandrel roll 30, which means are configured as displacement means 45 for the mandrel rolls 30 in this exemplary embodiment, whereby for this purpose, an eccentric device 46, which is individually motor-driven, in each instance, and on which each of the mandrel rolls 30 is mounted, in each instance, is utilized in the embodiment shown in FIGS. 1 and 2. It is understood that this eccentric device 46 can also serve as a return means 50.

(10) The relief means can comprise a releasable mandrel roll lock 41 of the respective mandrel roll 30 on the mandrel roll table 35 as shown in FIGS. 3 and 4, thereby making it possible to guarantee relief in structurally simple manner, because then, the mandrel roll 30 can be released, and no rolling forces can be applied any longer when the mandrel roll lock 41 is released. For example, it is conceivable to guide the mandrel roll 30 in an oblong hole 42 when the mandrel roll lock 41 is released, whereby the mandrel roll lock 41 can press the mandrel roll against an end of the oblong hole 42 when the mandrel roll 30 is locked in place by it. Accordingly, the mandrel roll lock then absorbs the rolling forces; when the mandrel roll lock is released, this absorption is no longer possible, so that the rolling process is ended.

(11) In the exemplary embodiment shown in FIGS. 1 and 2, the mandrel roll 30 on the eccentric device 46 stands closest to the mandrel roll table axle 36 in a rolling position 62, so that relatively little torque is introduced into the respective eccentric device 46 by rolling forces acting on the mandrel rolls 30. In this regard, it is possible, in the case of this exemplary embodiment, that the electric motor drives of the eccentric devices 46 can counter the rolling forces. It is understood that in deviating embodiments, additional locks, such as engagement devices of the like, can also be provided.

(12) If an eccentric device 46 is rotated about its axis, relative to its rolling position, particularly rotated by 180°, then the respective mandrel roll 30 gets into its release position.

(13) Furthermore, in this exemplary embodiment, measurement means 70 are disposed on the mandrel roll table 35 per mandrel roll 30, which means can measure the outside diameter of rings 15 situated in the roll gap 16 in this exemplary embodiment. In this exemplary embodiment, the measurement means 70 are configured as optical distance measurement devices. It is understood that other measurement means can also be used in modified embodiments.

(14) If a ring 15 is now applied to a mandrel roll 30 (mandrel roll position A), it is rolled out in the narrowing roll gap as the mandrel roll table 35 rotates in the direction of rotation 37, until the roll gap minimum (mandrel roll position B) has been reached. As the mandrel roll table 35 continues to rotate in the direction of rotation 37, the roll gap widens, so that no further rolling takes place, whereby the finished, rolled ring 15 can then be removed from the mandrel roll once again (mandrel roll position C).

(15) As is directly evident, variations in the insertion volume of the ring 15 cause significant variations in the ring diameter with this method management shown in FIG. 1.

(16) For this reason, the respective ring diameter is monitored by way of the measurement means 70, and the respective eccentric device 46 is switched into its release position 61 when a predetermined ring diameter has been reached.

(17) This is checked, in the present exemplary embodiment, by means of a comparison of the respective measurement values with a corresponding, predetermined value.

(18) This switch of the eccentric device 46 or of the mandrel roll 30 into the release position 61 particularly takes place before the roll gap minimum (mandrel roll position B) predetermined by the eccentricity has been reached, whereby a possible switch after the roll gap minimum is not critical, because the rolling process has already been ended here, in any case. When the ring 15 is removed (mandrel roll position C), an eccentric device 46 that is situated in its release position or a mandrel 30 that is situated in its release position 61 is switched back into the rolling position 62. This switch happens in the unstressed state in this exemplary embodiment, whereby in accordance with the present method management, this return step can also take place before or afterward, as long as it is ensured that a rolling process is not initiated or influenced as a result. It is understood that in modified embodiments, the eccentric device 46 can be displaced in the direction of its rolling position even during the rolling process.

(19) Thus, although only a few embodiments of the present invention have been shown and described, it is to be understood that many changes and modifications may be made thereunto without departing from the spirit and scope of the invention.