ROTATING ENTRY SYSTEM WITH FRONT END OR FRONT AND REAR DRIVE SYSTEM

Abstract

A rolling mill rotating entry system (RES) with at least one front end-driven drum that indexes alignment of the RES guide path and drum with the bar stock transfer guide path. The front end drive system is offset from the bar stock transfer path, so that the bar stock has sufficient clearance to enter the guide path. The front end drive system facilitates desired indexed alignment of the RES guide path and the bar stock transfer path without the need for front end braking or damping systems that are customarily used with rear driven drums in known RES systems. Other RES embodiments include a rear drive system that drives the drum in tandem with the front drive system.

Description

BACKGROUND

1. Field

Embodiments of the present invention relate to a rotating entry system (RES) type of product handling system in a bar mill that produces long bar or rod products, wherein as part of a bar handling system the RES can receive long bar product from the rolling mill and then deliver the product onto a cooling bed. More particularly embodiments of the present invention relate to RES front end drive systems, alone or in combination with rear drive systems.

2. Description of the Prior Art

A conventional known rotating entry system (RES)-type product handling system is shown and described in U.S. Pat. No. 7,219,521, issued May 22, 2007, the entire contents of which is incorporated by reference herein. As shown in FIGS. 1 and 2 herein, a conventional known rotating entry system-type (RES) product handling system 10, has one or more guide channels 18a, 18b with corresponding rotatable drums 20a, 20b, typically about 90 meters (291 feet) long; a support structure 16; and a drive motor 30 for each drum that is located at the exit end of the RES. Known RES apparatus locates the drum drive 30 at the rear or downstream end of the drum, for concentric alignment of the drive and its corresponding driven drum shaft A_l, A₂. A concentrically aligned drive cannot be utilized at the front upstream or loading end of the drum as it would block the rolled bar transfer path leading into the guide channel 18a, 18b.

In the known RES apparatus of FIGS. 1 and 2, each drum has at least one drum channel 22a, 22b formed. within the outer drum periphery parallel to its corresponding guide channel 18a, 18b. Each drum 20a, 20b may have a plurality of drum channels 22a, 22b: for example four oriented 90° intervals about the drum circumference. During mill operation, a rolled bar enters one of the guide channels 18a, 18b in its receiving position. After the entire bar is inside its corresponding guide 18a, 18b the corresponding rotatable drum 20a, 20b, driven by a rear end motor 30, rotates and stops to a receiving position to accept the bar in a corresponding drum channel 22a, 22b. Thereafter the drum 20a, 20b rotates to a discharge position—typically at about 90 degrees from its receiving position—to discharge the bar to underlying cooling beds 14. At the end of the start/stop (or indexing) sequence of the drum 20a, 20b, the adjacent guide channels 18a, 18b are at the receiving position for the next coming bar after time gap of a few seconds The rotatable drum 20a, 20b includes more than 10 modular sub-assemblies that are connected in-line by couplings. A typical six-meter (20 feet) long modular sub-assembly has guide channels mounted on a rotating shaft A₁, A₂ that is supported by roller bearings (not shown).

The typical 90 degree indexing of the rotatable drum 20a, 20b during operation occurs in up to a few seconds to meet high tonnage production requirement. For a rear end drive 30 RES, the front end receiving guide can experience a phase lag delay in rotation indexing during an indexing operation performed by the rear drive. The phase lag is attributable to the lengthy rotatable drum, which can be modeled analytically as a series of torsional spring and inertia systems. Due to the delay and the short time indexing the front end of the drum 20a, 20b tends to oscillate, which may cause indexing misalignment between the incoming bar and its corresponding guide channel 18a, 18b. If gross indexing misalignment occurs the incoming bar may cobble and block the bar transfer path when its front end misses its corresponding guide channel 18a, 18b, leading to production disruption until the cobbled bar is removed from the bar transfer path. In known RES apparatus drum/guidepath misalignment is suppressed via a damping or a braking mechanism (not shown). The braking or damping systems help reduce or control drum front end oscillation, but they do not prevent such oscillation. Such braking or damping systems add construction and service complexity to the RES apparatus.

SUMMARY

Accordingly, embodiments of the present invention include an RES with a front end-driven drum that indexes alignment of the RES guide path and drum with the bar stock transfer path. The front end drive system is in an offset orientation from the bar stock transfer path, so that the bar stock has sufficient clearance to enter the guide path. In some embodiments the front end drive system incorporates pass-through slots aligned with the bar stock transfer path, for through passage of the stock. Other RES embodiments of the present invention include a rear drive system that drives the drum in tandem with the front drive system.

More specifically embodiments of the present invention include a rolling mill rotating entry system, having a drum rotatable about an axis. The drum has a front axial end and a rear axial end, and at least one drum channel capable of receiving stock translated into the drum from the front to rear ends along a downstream transfer path that is established when the drum is rotated to a loading position and discharging stock from the drum channel when the drum is rotated to a discharge position. The system also has a drive coupled to the drum proximal the front axial end thereof, for rotating the drum. The drive is oriented offset from and not impeding the stock downstream transfer path.

Another exemplary embodiment of the present invention includes a rolling mill rotating entry system, comprising coupled in series: a roll stand for translating rolled stock along a transfer path; a stock shear and transfer switch for respectively shearing stock to a desired length and selectively continuing stock translation along at least one downstream transfer path; a guide structure for guiding stock translation along the downstream transfer path; a drum rotatable about an axis; and a cooling bed for receiving stock discharged from the drum. The drum has a front axial end in proximity to the guide structure and a rear axial end, and at least one drum channel capable of receiving stock translated from the front to the rear end along the downstream transfer path when the drum is rotated to a loading position and discharging stock from the drum channel when the drum is rotated to a discharge position. A drive is coupled to the drum proximal the front axial end thereof, for rotating the drum, with the drive oriented offset from and not impeding the stock transfer path.

Yet another exemplary embodiment of the present invention includes a rolling mill rotating entry system, comprising coupled in series: a roll stand for translating rolled stock along a transfer path; a stock shear and transfer switch for respectively shearing stock to a desired length and selectively continuing stock translation along a plurality of downstream transfer paths; a plurality of respective guide structures corresponding to each downstream transfer path for guiding stock translation along said downstream transfer path; a plurality of respective drums corresponding to each downstream transfer path; and a cooling bed for receiving stock discharged from at least one respective drum. Each drum is rotatable about an axis, having a front axial end in proximity to the respective guide structure and a rear axial end. Each drum has at least one drum channel capable of receiving stock translated from the front to the rear end thereof along the downstream transfer path when the drum is rotated to a loading position and discharging stock from the drum channel when the drum is rotated to a discharge position. A drive is coupled to at least one respective drum proximal the front axial end thereof, for rotating the respective drum. The drive is oriented offset from and not impeding the stock downstream transfer path.

Further features of embodiments of the present invention, and the advantages offered thereby, are explained in greater detail hereinafter with reference to specific embodiments illustrated in the accompanying drawings. The features of the present invention may be applied jointly or severally in any combination or sub-combination by those skilled in the art.

BRIEF DESCRIPTION OF THE DRAWINGS

The teachings of the present invention can be readily understood by considering the following detailed description in conjunction with the accompanying drawings, in which:

FIG. 1 illustrates a schematic plan view of a known RES;

FIG. 2 illustrates a sectional elevational view of the known RES of FIG. 1, taken along 2-2 thereof;

FIG. 3 illustrates a schematic plan view of an RES, in accordance with an exemplary embodiment of the present invention;

FIG. 4 illustrates a partial plan view of front end drive and driven rotatable drum portions of an RES, in accordance with an exemplary embodiment of the present invention;

FIG. 5 illustrates a partial elevational view of front end drive and driven rotatable drum portions of FIG. 4, in accordance with an exemplary embodiment of the present invention;

FIG. 6 illustrates a front elevational view of a front end drive and guide bracket assembly of the RES of FIGS. 4 and 5, in accordance with an exemplary embodiment of the present invention;

FIG. 7 illustrates a partial cutaway front elevational view of a front end drive of FIG. 6 without the guide bracket assembly, in accordance with an exemplary embodiment of the present invention;

FIG. 8 illustrates a radial cross sectional view of the support structure and driven rotatable drum portions of FIGS. 4 and 5, taken along 8-8 of FIG. 4, in accordance with an exemplary embodiment of the present invention;

FIG. 9 illustrates a cross sectional view of the front end drive and driven rotatable drum portions of FIGS. 4 and 5, without the guide bracket assembly, in accordance with an exemplary embodiment of the present invention;

FIG. 10 illustrates a schematic plan view of an RES with front and rear drive systems, in accordance with an exemplary embodiment of the present invention; and

FIG. 11 illustrates a schematic plan view of an RES with front and rear drive systems, in accordance with another exemplary embodiment of the present invention.

To facilitate understanding, identical reference numerals have been used, where possible, to designate identical elements that are common to the figures.

DETAILED DESCRIPTION

To facilitate an understanding of embodiments, principles, and features of the present invention, they are explained hereinafter with reference to implementation in illustrative embodiments. In particular, they are described in the context of being a rotating entry system (RES) in a rolling mill. After considering the following description, those skilled in the art will clearly realize that the teachings of the present invention can be readily utilized in an RES front end drive system. Aspects of the present invention can provide a front end drive rotating entry system (RES) to reduce, if not eliminate, front end oscillation caused by a known rear-end drive RES, and thus enable a smooth and reliable receiving discharging operation. Embodiments of the present invention can index the rotatable drum with two synchronized drive systems mounted one at the front and one at the rear end of an RES.

RES Subsystem Operational Overview

With reference initially to FIG. 3, in accordance with a preferred embodiment of the present invention a front end drive RES product handling system and its associated bar stock transfer path is generally depicted at 10′ between the last roll stand 12 of a rolling mill and a receiver comprising a conventional carryover cooling bed 14. The system 10′ includes a support structure 16. At least one rotatable drum (here two drums 20a, 20b) are interposed between the support structure 16 and the cooling bed 14. The drums 20a, 20b are rotatable about their respective shafts, referenced by axes A₁, A₂. Long products such as bars, rods and the like exiting from the last roll stand 12 are directed along a transfer path by a switch 24 to a shear 26 for subdivision into shorter product lengths. The switch 24 and shear 26 act in concert in a known manner to direct the subdivided product lengths along respective downstream transfer paths alternatively to one and then the other of a pair of guide pipes 28a, 28b, having delivery ends aligned respectively with the drums 20a, 20b. As described below, the rotating drums 20a, 20b transfer bar stock product from the guide pipe 28a, 28b outlets to the cooling bed 14, completing the downstream transfer path.

As further shown in FIG. 3, the front end drive RES 10′ in accordance with the present invention includes at least one rotatable drum (here two drums 20a, 20b), each with a corresponding drum channel (not shown) for receipt of bar stock that is fed along a respective downstream transfer path, a support structure 16, and a corresponding front-end drive system 40. The front-end drive system 40 can be mounted on a support structure 16 either above or under the corresponding rotatable drum 20a, 20b, offset from the bar stock transport or transfer guide path. With a front end drive 40 RES, oscillation experienced by a drum 20a, 20b front end and its corresponding channel as compared to that of a known rear-end drive RES apparatus is reduced, if not eliminated. After an indexing sequence, an adjacent guide and drum channel can be positioned precisely at their relative receiving position—at the shortest possible time due to a lower (if not functionally insignificant) time delay—as compared to a known rear-driven RES 10 of FIG. 1. In embodiments of the present invention any relative oscillation of a drum and associated drum channel now occurs at the rear end of the RES 10′, and thus does not affect bar stock receiving/discharging operation, because the bar stock is only ejected circumferentially/laterally out of the drum's open exposed drum channel onto the cooling bed 14. Damping or braking mechanisms, previously utilized in known RES apparatus to suppress front drum and guide relative oscillation, are not needed when practicing the present invention. Elimination of such mechanisms reduces RES manufacturing cost, increases potential operational reliability and simplifies the system.

Further embodiments of the present invention, shown in FIGS. 11 and 12 can index the rotatable drums 20a, 20b with two tandem synchronized drive system motors: a first drive system/motor 40 mounted at the front and a second drive system (30 or 40′) mounted to the rear of the RES, to obtain a stable operation with increased tonnage production demand and lower operating load on each tandem drive (40 front drive/30 or 40′ rear drive) than would be handled by a single drive.

RES Front End Drive Structure

Referring to FIGS. 4-10 each individual modular drum 20a, 20b section is a known, fabricated structure of circumferentially arrayed, parallel, and generally U-shaped open-ended drum channels 22a, 22b that are affixed to and axially aligned with rotating drum shafts (designated by respective rotational axes A_l and A₂). As shown in FIG. 8, the modular drum sections are aligned and coupled together axially in tandem in known fashion to form the complete drum structures 20a, 20b. The respective first and second drums 20a, 20b are aligned axially and in series between its respective corresponding guide pipe 28a, 28b discharge outlet and the cooling bed 14. As shown in FIG. 8, channel guides 18a, 18b are offset from and abut drums 20a, 20b, in order to block the open ends of the corresponding drum channels 22a, 22b between the bar stock loading and dropping positions, so that the bar stock product transported therein does not drop prematurely from the drum channels.

In the present invention embodiment the drums 20a, 20b relative rotation and indexing operations are performed by a front end drive 40 that is coupled to and separately drives each respective drum shaft A₁, A₂ proximal the drum axial front end (i.e., the portion of the bar stock transfer path that is upstream of the drum). The drums 20a, 20b and their corresponding guide pipes 28a, 28b outlets, are aligned for receipt of bar stock in the drum channels 22a, 22b, in a loading position that constitutes a portion of the bar stock transfer path. The front end drive 40 rotates the drums 20a, 20b to their respective discharge or dropping positions for subsequent transfer dropping/discharge of the stock to the cooling bed 14. The drums 20a, 20b respective indexing and timing sequences for loading and discharging stock are performed by the front end drive 40 in a similar fashion as was performed by the known rear end drive 30 described in U.S. Pat. No. 7,219,521, that is incorporated by reference herein.

As previously noted the front end drive 40 is oriented offset from the bar stock transfer path between the guide pipes 28a, 28b and their corresponding drums 20a, 20b. Referring to FIGS. 4-10, the front end drive 40 includes a drive support structure and shroud 42 that is coupled to the RES support structure 16. The drive includes a pair of servo motors 44, each of which separately drives one of the drums 20a, 20b via a separately dedicated gear train 46. The servo motors 44 drive the drums 20a, 20b in previously described step-like start/stop fashion. Within each gear train 46 the drive gear 48, of known construction, is coupled to the servo motor 44 and transfers rotational power to driven gear 52 through intermediate gear 50. One or more intermediate gears may be incorporated in the gear train between the drive gear 48 and driven gear 52. A suitable gear ratio between the drive gear 48 and driven gear 52 is 40:1. Each driven gear 52 is coupled to its respective drum shaft A₁, A₂ and defines axial pass-through slots 54 within its hub structure corresponding to the number and radial orientation of drum channels 22a, 22b. The individual slots 54 are in communication with its corresponding drum channel 22a, 22b as well as the outlet portions of the guide pipes 28a, 28b.

The previously described components and materials herein as making up the various embodiments are intended to be illustrative and not restrictive. Many suitable components and materials that would perform the same or a similar function as the materials described herein are intended to be embraced within the scope of embodiments of the present invention. While embodiments of the present invention have been disclosed in exemplary forms, it will be apparent to those skilled in the art that many modifications, additions, and deletions can be made therein without departing from the spirit and scope of the invention and its equivalents, as set forth in the following claims.

Claims

1. A rolling mill rotating entry system, comprising: a drum rotatable about an axis, having a front axial end and a rear axial end, at least one drum channel capable of receiving stock translated into the drum from said front end toward said rear end thereof along a downstream transfer path that is established when the drum is rotated to a loading position and discharging stock from the drum channel when the drum is rotated to a discharge position; anda drive coupled to the drum proximal the front axial end thereof, for rotating the drum, the drive oriented offset from and not impeding the stock downstream transfer path.

2. The system of claim 1, wherein the drive comprises a motor coupled to a drive gear of a gear train, and a driven gear of the gear train coupled to the drum.

3. The system of claim 2, wherein the driven gear has a hub that defines at least one through-passage slot for unimpeded passage of stock therethrough along the downstream transfer path.

4. The system of claim 3, wherein the driven gear is coupled to a rotatable drum shaft that is coupled to the drum.

5. The system of claim 4, wherein: the drum has a plurality of drum channels oriented parallel to the drum rotational axis about a periphery of the drum; andthe driven gear defines a plurality of respective through-slots aligned with each respective drum channel along the downstream transfer path.

6. The system of claim 5, wherein the motor is a servo motor for rotating the drum in step-like start/stop motion from the loading position to the discharge position.

7. The system of claim 1, wherein the drive system defines at least one through-passage slot for unimpeded passage of stock therethrough along the downstream transfer path.

8. The system of claim 7, wherein: the drum has a plurality of drum channels oriented parallel to the drum rotational axis about a periphery of the drum; andthe drive system defines a plurality of respective through-passage slots aligned with each respective drum channel along the downstream transfer path.

9. The system of claim 8, wherein the drive comprises a motor coupled to a drive gear of a gear train, and a driven gear of the gear train coupled to the drum, the driven gear having a hub defining the through-passage slots.

10. A rolling mill line system with a rotating entry system for a cooling bed, comprising coupled in series: a roll stand for translating rolled stock along a transfer path;a stock shear and transfer switch for respectively shearing stock to a desired length and selectively continuing stock translation along at least one downstream transfer path;a guide structure for guiding stock translation along the downstream transfer path;a drum rotatable about an axis, having a front axial end in proximity to the guide structure and a rear axial end, at least one drum channel capable of receiving stock translated from said front end toward said rear end thereof along the downstream transfer path when the drum is rotated to a loading position and discharging stock from the drum channel when the drum is rotated to a discharge position;a drive coupled to the drum proximal the front axial end thereof, for rotating the drum, the drive oriented offset from and not impeding the stock transfer path; anda cooling bed for receiving stock discharged from the drum.

11. The system of claim 10, wherein the drive comprises a motor coupled to a drive gear of a gear train, and a driven gear of the gear train coupled to the drum.

12. The system of claim 11, wherein the drive comprises a motor coupled to a drive gear of a gear train, and a driven gear of the gear train coupled to the drum.

13. The system of claim 12, wherein the driven gear has a hub that defines at least one through-passage slot for unimpeded passage of stock therethrough along the downstream transfer path.

14. The system of claim 13, wherein the driven gear is coupled to a rotatable drum shaft that is coupled to the drum.

15. The system of claim 14, wherein: the drum has a plurality of drum channels oriented parallel to the drum rotational axis about a periphery of the drum; andthe driven gear defines a plurality of respective through-slots aligned with each respective drum channel along the downstream transfer path.

16. The system of claim 10, wherein the drive system defines at least one through-passage slot for unimpeded passage of stock therethrough along the downstream transfer path.

17. The system of claim 16, wherein: the drum has a plurality of drum channels oriented parallel to the drum rotational axis about a periphery of the drum; andthe drive system defines a plurality of respective through-passage slots aligned with each respective drum channel along the downstream transfer path.

18. A rolling mill line system with a rotating entry system, comprising coupled in series: a roll stand for translating rolled stock along a transfer path;a stock shear and transfer switch for respectively shearing stock to a desired length and selectively continuing stock translation along a plurality of downstream transfer paths;a plurality of respective guide structures corresponding to each downstream transfer path for guiding stock translation along said downstream transfer path;a plurality of respective drums corresponding to each downstream transfer path, each drum rotatable about an axis, having a front axial end in proximity to the respective guide structure and a rear axial end, at least one drum channel capable of receiving stock translated from said front end toward said rear end thereof along the downstream transfer path when the drum is rotated to a loading position and discharging stock from the drum channel when the drum is rotated to a discharge position;a drive coupled to at least one respective drum proximal the front axial end thereof, for rotating the respective drum, the drive oriented offset from and not impeding the stock downstream transfer path; anda cooling bed for receiving stock discharged from at least one respective drum.

19. The system of claim 18, wherein at least one drive system defines at least one through-passage slot for unimpeded passage of stock therethrough along the downstream transfer path.

20. The system of claim 19, wherein: at least one drum has a plurality of drum channels oriented parallel to the drum rotational axis about a periphery of the drum; andat least one drive system defines a plurality of respective through-passage slots aligned with each respective drum channel along the downstream transfer path.