ROLLER REPLACING APPARATUS AND METHOD FOR RAPIDLY REPLACING WORKING ROLLER BASED ON ROLLER REPLACING APPARATUS

Abstract

A roll changing device is applicable to a multi-roll mill. Under a roll changing state, assembly parts of the work rolls and the bearing chocks have a lateral movement space with the internal width not less than the assembly width of the work rolls and the bearing chocks in a lateral direction of the assembly parts moving along a rolling strip in a mill house, and the movement space allows another work rolls to coexist with used work rolls in the mill house before the used work rolls are pulled out. The roll changing device is provided with at least two rows of clamping heads, one row of clamping heads corresponding to an inlet side are inlet clamping heads, another row of clamping heads close to an outlet side are outlet clamping heads, each row of clamping heads comprises a pair of upper and lower clamping heads arranged in parallel.

Claims

1. A roll changing device, adapted for a multi-roll mill, wherein: work rolls of the multi-roll mill are not provided with bearing chocks, or the work rolls are provided with bearing chocks, but assembly parts of the work rolls and the bearing chocks have a lateral movement space with an internal width no less than an assembly width of the work rolls and the bearing chocks in a lateral direction of the assembly parts moving along a rolling strip in a mill house in a roll changing state, and the lateral movement space allows another group of work rolls to coexist with the work rolls in the mill house before the work rolls are pulled out of the mill house; and the roll changing device is provided with at least two rows of clamping heads, one row of clamping heads corresponding to an inlet side of the rolling strip are configured as inlet clamping heads, another row of clamping heads close to an outlet side of the rolling strip are configured as outlet clamping heads, each row of clamping heads comprises a pair of upper and lower clamping heads which are arranged in parallel.

2. The roll changing device according to claim 1, wherein the clamping heads comprise bottom bracket grooves, and clampers capable of applying an acting force to a direction of the bracket grooves for clamping the work rolls tightly are arranged on upper portions of the bracket grooves at intervals.

3. The roller changing device according to claim 1, wherein the clamping heads of the roll changing device are connected to clamping driving ends.

4. A work roll changing method adopting the roll change device according to claim 1, wherein through cooperation of the roll changing device and work roll brackets, the work rolls are changed with the roll changing device entering and exiting from the mill house of the mill only once, and the method comprising the following steps: (1) switching the mill to the roll changing state, opening a roll gap, and holding up a pair of used work rolls to be changed by work roll brackets at an inlet side of the mill, while laterally moving the pair of used work rolls towards the inlet side of the mill; (2) enabling the roll changing device to enter the mill house, loading a pair of new work rolls by outlet clamping heads of the roll changing device, and enabling inlet clamping heads to be in an empty carriage state; (3) enabling the roll changing device to enter the mill house along an axial direction of the work rolls, and enabling the new work rolls loaded by the outlet clamping heads to be in position exactly in the axial direction during the process; (4) holding up the new work rolls by work roll brackets at an outlet side of the mill; (5) clamping the pair of used work rolls which are already close to the inlet side by the inlet clamping heads of the roll changing device; (6) enabling the work roll brackets at the inlet side to retract to a rolling state, and fixing the pair of used work rolls at the inlet side only by the inlet clamping heads of the roll changing device at the moment, and meanwhile, holding up the pair of new work rolls just pushed in from the outlet side by the work roll brackets at the outlet side; (7) unclamping the pair of new work rolls located at the outlet side by the outlet clamping heads of the roll changing device, and holding up the new work rolls only by the work roll brackets at the outlet side at the moment; (8) enabling the roll changing device to exit from the mill house: loading the pair of used work rolls by the inlet clamping heads of the roll changing device, and enabling the outlet clamping heads to be in the empty carriage state; and (9) switching the mill to the rolling state, closing the roll gap, and enabling the work roll brackets at the outlet side to retract to the rolling state, and ending roll changing.

5. The efficient work roll changing method according to claim 4, wherein when the work rolls are changed in the steps (1)-(9), the operations on the outlet side and the inlet side are performed in a reversed order, that is, the used rolls are moved towards the outlet side, the new rolls enter from the inlet side, and the used rolls and the new rolls are staggered in the mill house.

6. The efficient work roll changing method according to claim 4, wherein each row of clamping heads can only clamp a single work roll.

7. The efficient work roll changing method according to claim 4, wherein before the new work rolls enter the mill house to be in position and the used work rolls are pulled out of the mill house, the new work rolls and the used work rolls coexist in the mill house, and the new work rolls are not in contact with the used work rolls.

8. The efficient work roll changing method according to claim 4, wherein the roll changing device loads the new work rolls to-be-changed before entering the mill house for roll changing.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0038] FIG. 1 is a rolling state diagram of a multi-roll mill in the prior art;

[0039] FIG. 2 is a work roll changing preparation state diagram of FIG. 1;

[0040] FIG. 3 is a work roll changing state diagram (a roll changing device is outside a mill house) of FIG. 1;

[0041] FIG. 4 is a work roll changing state diagram (a roll changing device is in a mill house) of FIG. 1;

[0042] FIG. 5 is a roll changing device implemented according to the present invention;

[0043] FIG. 6 is another stereoscopic diagram of FIG. 5;

[0044] FIG. 7 is a diagram of a mill switched from a rolling state to a work roll changing preparation state according to an efficient work roll changing method of the present invention;

[0045] FIG. 8 is a state diagram of changing of work rolls of a mill implemented according to an efficient work roll changing method of the present invention (a roll changing device is outside a mill house when new rolls are pushed in);

[0046] FIG. 9 is a state diagram of changing of work rolls of a mill implemented according to an efficient work roll changing method of the present invention (a roll changing device is in a mill house);

[0047] FIG. 10 is a partial schematic diagram (intermediate rolls are omitted) of a state diagram of changing of work rolls of a mill implemented according to an efficient work roll changing method of the present invention (a roll changing device is in a mill house); and

[0048] FIG. 11 is a state diagram of changing of work rolls of a mill implemented according to an efficient work roll changing method of the present invention (intermediate rolls are omitted when used rolls are pulled out).

DESCRIPTION OF THE EMBODIMENTS

[0049] A roll changing device according to the present invention shown in FIG. 5 and FIG. 6 is applicable to a multi-roll mill and is characterized in that the multi-roll mill is not provided with bearing chocks, or work rolls are provided with bearing chocks. In a roll changing state, assembly parts of the work rolls and the bearing chocks have a lateral movement space with an internal width no less than an assembly width of the work rolls and the bearing chocks in a lateral direction of the assembly parts moving along a rolled strip in a mill house, and the lateral movement space allows another group of work rolls to coexist with used work rolls in the mill house before the used work rolls are pulled out of the mill house. The roll changing device 1 shown in FIG. 5 and FIG. 6 is provided with two rows of clamping heads (inlet clamping heads 3 and outlet clamping heads 2) corresponding to an inlet and an outlet of the rolling strip, the inlet clamping heads 3 and the outlet clamping heads 2 each comprise a pair of upper and lower clamping heads, and the four clamping heads are arranged in parallel.

[0050] Further, the inlet clamping heads 3 and the outlet clamping heads 2 comprise bottom bracket grooves, and clampers capable of applying an acting force to the bracket grooves for clamping the work rolls tightly are arranged on upper portions of the bracket grooves at intervals. The bracket grooves are not limited to the shape in which the bearing bush-shaped internal arc in the figures matches the work rolls, and also may be in shapes in which the work rolls can be clamped, such as a v shape.

[0051] Further, the inlet clamping heads 3 and the outlet clamping heads 2 are connected to clamping driving ends of head ends.

[0052] According an efficient work roll changing work roll method according to the present invention shown in FIGS. 7-11, an 18-roll mill is taken as an example for describing a typical efficient work roll changing implementation. A similar roll changing method may also be adopted for efficient roll changing by other mills such as a 20-roll mill and a 36-roll mill.

[0053] The present invention utilizes the typical feature that the work rolls of such multi-roll mills are not provided with bearing chocks and have a certain lateral movement space in the mill house, and two working processes of “pushing new rolls in and pulling used rolls out” are provided. Through the lateral movement space of the work rolls moving along the rolled strip in the mill house, the used work rolls move laterally (along an inlet or outlet direction of the rolling strip) when the mill switches to a roll changing state, thus an appropriate space is reserved for the new work rolls entering the mill house at first, and the new work rolls and the used work rolls can be placed in the mill house side by side, and details are as follows.

[0054] (1) A mill switches to a roll changing state (shown in FIG. 7), a roll gap is opened, work roll brackets at an inlet side hold up a pair of used work rolls 8 needing to be changed (or a single work roll, a pair of work rolls taken as an example herein), and meanwhile laterally move toward the inlet side of the mill.

[0055] (2) As shown in FIG. 8, a roll changing device 1 enters a mill house of the mill, outlet clamping heads 2 of the roll changing device load a pair of new work rolls 8, and inlet clamping heads 3 are in an empty carriage state.

[0056] (3) The roll changing device 1 enters the mill house, and the new work rolls 8 loaded by the outlet clamping heads 2 are in position exactly in an axial direction during the process.

[0057] (4) Work roll brackets 5 at an outlet side hold up the new work rolls 8, as shown in FIG. 9 and FIG. 10.

[0058] (5) The inlet clamping heads 3 of the roll changing device 1 clamp the pair of used work rolls 8 close to the inlet side, as shown in FIG. 9 and FIG. 10.

[0059] (6) The work roll brackets 4 at the inlet side retract to a rolling state (the pair of used work rolls 8 at the inlet side are fixed only by the inlet clamping heads 3 of the roll changing device 1 at the moment), and meanwhile, the work roll brackets 5 at the outlet side hold up the pair of new work rolls 8 just pushed in from the outlet side and stay still.

[0060] (7) The outlet clamping heads 2 unclamp the pair of new work rolls 8 located at the outlet side (the new work rolls 8 are held up only by the work roll brackets 5 at the outlet side at the moment).

[0061] (8) As show in FIG. 11, the roll changing device 1 exits from the mill house, with the inlet clamping heads 3 loading the pair of used work rolls 8, and the outlet clamping heads 2 being in an empty carriage state.

[0062] (9) The mill switches to the rolling state (referring to a rolling state of a general mill in FIG. 1), the roll gap is closed, the work roll brackets 5 at the outlet side retract to the rolling state, and roll changing is completed.

[0063] Compared with traditional roll changing methods, the efficient work roll changing method of the present invention has the advantages that operation times of the roll changing device are reduced, the roll changing time can be shortened by 30-60%, especially for wide strip steel mills with the longer movement distance of the roll changing device entering and exiting from the mill house, the roll changing time is significantly shortened by using the method of the present invention, and the operability of the mill is improved.