CN210701711U

CN210701711U - Magnesium alloy thin strip rolling tension blending device

Info

Publication number: CN210701711U
Application number: CN201920933438.3U
Authority: CN
Inventors: 胡小东; 赵红阳; 王振敏; 卢艳青; 陈明; 张举
Original assignee: University of Science and Technology Liaoning USTL
Current assignee: University of Science and Technology Liaoning USTL
Priority date: 2019-06-20
Filing date: 2019-06-20
Publication date: 2020-06-09
Anticipated expiration: 2029-06-20

Abstract

The utility model relates to a metal material rolling processing technology field, in particular to magnesium alloy thin strip rolling tension allotment device, characterized by is provided with tension allotment roller set between two adjacent rolling mills. The tension allocating roller group comprises upper rollers and lower rollers, and the number of the upper rollers is the same as or different from that of the lower rollers. And the number difference value of the upper rollers and the lower rollers in the tension allocating roller group is 1. And the driving motor of the upper roller or the lower roller is connected with a torque controller. Compared with the prior art, the utility model has the advantages that: 1) a tension adjusting device is arranged between the two rolling mills to change the front tension and the rear tension of the plate strip and stabilize the adjusted tension. 2) Finally, the rolling efficiency is improved and good plate shape is obtained. 3) The utility model is suitable for a hot rolling, warm rolling, cold rolling of magnesium alloy slab band, but not limited to magnesium alloy also is applicable to in other metals such as metal slab bands such as steel, copper, aluminium and other need different front and back tensile strip applications.

Description

Magnesium alloy thin strip rolling tension blending device

Technical Field

The utility model relates to a metal material rolling processing technology field, in particular to can improve rolling efficiency and obtain the rolling tension blending device of magnesium alloy thin strip of good board type.

Background

Tension is an important parameter in the continuous rolling process, and reasonable tension is the premise of improving the rolling efficiency and obtaining good plate shapes. In the continuous rolling process, the tension between the frames can be divided into front tension and rear tension, the front tension of the front rolling mill is the rear tension of the rear rolling mill, and the front tension and the rear tension applied to the plate strip between the two frames are equal in magnitude and opposite in direction. The tension at two ends of the continuous rolling unit can be controlled by an unreeling machine and a reeling machine, wherein the front tension of the last rolling machine is controlled by the reeling machine, and the rear tension of the first rolling machine is controlled by the unreeling machine. The effects of front tension and rear tension on the plate strip are different during rolling, the effect of the rear tension on reducing the rolling force and increasing the pass reduction is larger, the effect of the front tension on controlling the plate shape is larger, and the tension is generally set to be 0.2-0.8 times of the yield strength of the material.

The tension between the frames can be adjusted through the rolling speed between the frames, and the micro-tension control can be performed on the continuous rolling process through a sleeve picking device and the like. Chinese utility model patent CN203917404U discloses "a cold continuous rolling mill inter-frame strip steel tension control device", this patent drives the dancer rools through the pneumatic cylinder and reciprocates and adjust the tensile size between two frames. When the tension is large, the adjusting rollers rise, the length of the strip steel stored between the adjusting rollers is released, and the tension of the strip steel between the frames is reduced; when the tension is small, the adjusting roller descends, the storage length of the strip steel between the two frames is increased, and the tension of the strip steel is increased. The tension control device is equivalent to a sleeve picking device, and the tension cannot be continuously adjusted when the stroke of the adjusting roller reaches the limit position. When the tension is controlled by the mill speed or the loop, the tension of the strip between the two stands is generally equal or similar. Because the front tension and the rear tension have different functions in rolling, the ideal condition is to control and distribute the front tension and the rear tension so as to achieve the purposes of improving the rolling efficiency and obtaining good plate shapes.

The magnesium alloy has low density and small heat capacity, so the temperature of the magnesium alloy strip between the tandem mill frames is reduced rapidly, and particularly the temperature is reduced obviously when thinner magnesium alloy strips are rolled. When the magnesium alloy is hot rolled, the temperature of a rolled piece is higher, the temperature of the strip is reduced after the strip is discharged from the rolling mill, and the strip enters the next continuous rolling stand for rolling. When the magnesium alloy is warm-rolled, the temperature of a rolled piece is generally lower, the temperature of a roller is higher, the temperature of the rolled piece is increased after the rolled piece is taken out of a rolling mill, and the temperature of the rolled piece is reduced when the rolled piece enters the next rolling mill. Therefore, no matter hot continuous rolling or warm continuous rolling, the front tension of the plate strip between two continuous rolling stands is expected to be smaller at the outlet of one rolling mill, so that the plate strip is prevented from being narrowed and even broken by large tension due to high temperature and low strength of the plate strip at the outlet of the rolling mill, and the rear tension at the inlet of the next rolling mill is expected to be larger, so that the next rolling mill rolls under the condition of large rear tension, and therefore the rolling reduction of the stand can be improved, thinner plate strip products can be obtained in the same pass, and in addition, good plate shapes can be obtained. Similar conditions are also present in hot and cold continuous rolling of other metals.

Disclosure of Invention

The utility model aims at providing a magnesium alloy thin strip rolling tension blending device overcomes prior art's is not enough, sets up controllable resistance device between two rolling mills, changes the tensile size in tension and back before the slab band to reach the tensile purpose of allotment between the frame, and enable the tension after the allotment and remain stable, tension regulation can adopt multiple form to go on, can improve rolling efficiency finally and obtain good board type.

In order to achieve the above object, the solution of the present invention is that:

a tension adjusting roller set is arranged between two adjacent rolling mills, and applies acting force with adjustable size and direction to passing strips, so that the rear tension between two adjacent stands is larger than the front tension or smaller than the front tension.

The tension allocating roller group comprises upper rollers and lower rollers, and the number of the upper rollers is the same as or different from that of the lower rollers.

And the number difference value of the upper rollers and the lower rollers in the tension allocating roller group is 1.

And the driving motor of the upper roller or the lower roller is connected with a torque controller.

The tension blending roller set is arranged on the cantilever type or closed structure frame, and the distance between the upper roller and the lower roller is adjustable.

Compared with the prior art, the beneficial effects of the utility model are that: 1) the controllable allocating device is arranged between the two rolling mills, so that the front tension and the rear tension of the plate strip between the continuous rolling mill frames are changed, and the allocated tension can be kept stable within a certain range. 2) The tension adjusting device can adopt a closed type or cantilever type structure, can be conveniently moved away from the rack and is restored to a normal tension rolling state, and finally the rolling efficiency can be improved and a good plate shape can be obtained. 3) The utility model is suitable for a hot rolling, warm rolling, cold rolling of magnesium alloy slab band, but not limited to magnesium alloy also is applicable to in the tensile strip is used around other metals such as metal slab bands such as steel, copper, aluminium and other needs are different.

Drawings

FIG. 1 is a schematic drawing of the tension of a prior art continuous rolling mill.

Fig. 2 is a schematic structural diagram of an embodiment of the present invention.

Fig. 3 is a schematic structural diagram of the second embodiment of the present invention.

Fig. 4 is a schematic diagram of a third structure according to an embodiment of the present invention.

Fig. 5 is a schematic diagram of a fourth structure according to an embodiment of the present invention.

Fig. 6 is a schematic view of the cantilever type frame tension adjusting roller set structure.

In the figure: 1-rolling mill, 2-plate belt, 3-next rolling mill, 4-tension adjusting roller group, 5-torque controller, 6-lower roller, 7-upper roller and 8-speed reducer.

Detailed Description

The structure of the present invention will be further described with reference to the following embodiments:

in the description of the present invention, it is to be noted that, unless otherwise explicitly specified or limited, the terms "mounted," "connected," and "connected" are to be construed broadly, and may be, for example, fixedly connected, detachably connected, or integrally connected; may be directly connected or indirectly connected through an intermediate. The specific meaning of the above terms in the present invention can be understood in specific cases to those skilled in the art.

Referring to fig. 1, which is a schematic diagram of continuous rolling tension in the prior art, in conventional continuous rolling, the front tension of a strip 2 between stands is equal to the rear tension, and the tension is controlled by the rolling speeds of a rolling mill 1 and a subsequent rolling mill 3.

See fig. 2, is the utility model discloses magnesium alloy thin strip rolling tension allotment device embodiment a structure schematic diagram, set up a set of tension allotment roller set 4 of constituteing by 1 last roller and 1 lower roller between two continuous rolling stands (rolling mill 1 and a back rolling mill 3), tension allotment roller set 4 is through applying certain amount of reduction to slab band 2 when continuous rolling, and the rolling moment power that tension allotment roller set 4 produced is provided by back tension, and slab band 2 between the frame has when tension is balanced: f_{Rear end}=F_{Front side}+F_{Resistance device}

For example, when a magnesium strip of 200X 1mm is hot rolled, the strip exit temperature of the preceding rolling mill is 300 ℃ and the yield strength of the strip is 100MPa, if the strip is tensioned between the rolling mill 1 and the subsequent rolling mill 3 according to a yield strength equal to 0.2 times:

F_{front side}=F_{Rear end}=0.2×100×200×1=4000N

When the tension adjusting roller group 4 is arranged between the rolling mill 1 and the subsequent rolling mill 3, the diameters of the upper roller and the lower roller are 200mm, if the tension adjusting roller group applies 30000N pressure to the plate strip, and the contact arc length of the pressure roller and the plate strip is 2mm, the required rolling moment is 30000 multiplied by 2 multiplied by 0.5=30000 N.mm. The required moment of tension allotment roller set rotation is provided by back tension, has when tension reaches equilibrium:

F_{rear end}=F_{Front side}+F_{Resistance device}

4000=F_{Front side}+30000/100

F_{Front side}=4000-300=3700N

1. Due to the effect of the tension adjusting roller group between the two frames, the front and rear tensions of the plate belt between the two frames are 3700N and 4000N respectively when the tensions reach balance. The tension adjustment can be performed as long as the strip is continuously rolled between the frames, and is not limited by other conditions.

Fig. 3 is a schematic structural diagram of an embodiment two of the magnesium alloy thin strip rolling tension adjusting device of the present invention, a torque controller 5 is added on the basis of the embodiment one, the torque controller 5 can apply braking or driving torque to adjust tension between frames, for example, the torque controller applies 50n.m braking torque, and then 500N force needs to be additionally added to the post tension to balance the braking torque. When the applied rolling torque and braking torque reach tension balance, the front-to-back tension of the strip between the rolling mill 1 and the subsequent rolling mill 3 becomes 3200N and 4000N, respectively. The moment controller 5 can adjust the driving moment applied by the tension adjusting roller group and drive the tension adjusting roller group and the plate strip to pass through the tension adjusting roller group, when the plate strip forms continuous rolling in the rolling mill 1 and the next rolling mill 3, the driving moment changes the direction, and the tension of the rolling mills before and after adjustment reaches a set value and is stabilized.

The torque controller 5 is a magnetic powder brake with rated output of 50N.m and is connected with the tension adjusting roller group 4, the torque controller 5 can also be a magnetic powder brake friction plate or an electromagnetic brake with rated output of 5N.m, and the brake torque is amplified by a speed reducer 8 with the ratio of 1:10 and then is connected with the tension adjusting roller group 4.

See fig. 4, is the three structural schematic diagrams of the utility model discloses magnesium alloy thin strip rolling tension allotment device embodiment, in this system, tension allotment roller set comprises 3 rollers of 1 lower roll 6 and last roller 7 crossing arrangement, and every roller can be controlled by the moment controller, exerts resistance moment or moment of power. The slab band 2 is crooked from top to bottom when the tension allotment roller set, and slab band and lower roll 6 and the increase of 7 area of contact of last roller, and the slab band receives the frictional force direction and the direction of advance of tension allotment roller set this moment opposite, has when tension is balanced:

F_{rear end}=F_{Front side}+F_{Resistance device}

If the friction coefficient between the tension adjusting roller group and the plate strip is 0.1, when the average pressure of the plate strip on the roller surface of the tension adjusting roller group is 1000N, the friction resistance borne by the plate strip is 100N, the total friction resistance of 3 rollers is 300N, and when the tensions are balanced, the front tension and the rear tension of the plate strip between the rolling mill 1 and the subsequent rolling mill 3 are 3700N and 4000N respectively. Each roller can provide braking torque or driving torque by a torque controller to adjust the front and back tension between the frames. For convenient operation, the tension adjusting roller group can be composed of a lower roller 6 and an upper roller 7 which can move up and down in a cantilever type, when the plate strip 2 forms continuous rolling between the rolling mill 1 and the next rolling mill 3, the upper roller 7 moves downwards to adjust the distance between the upper roller 7 and the lower roller 6, thereby achieving the adjusting effect of adjusting the friction resistance and the tension between the frames. The cantilever type upper roller 7 can be moved away from the frame and is converted into a normal rolling state, and the lower roller 6 is lower than a rolling line after descending at a height during normal rolling and is not contacted with the plate strip 2.

See fig. 5, is the four schematic structural diagrams of the embodiment of the magnesium alloy thin strip rolling tension allocating device of the utility model, in the system, the tension allocating roller set is a roller set consisting of 3 lower rollers 4 and 2 upper rollers 5, the upper rollers and the lower rollers can be controlled by a torque controller, and resistance torque or dynamic torque is applied. The slab band 2 is crooked from top to bottom when the roller set, and slab band and lower roll 6 and the increase of 7 area of contact of roller, and the slab band receives the frictional force direction and the direction of advance of roller set this moment opposite, has when tension is balanced:

F_{rear end}=F_{Front side}+F_{Resistance device}

If the friction coefficient between the tension adjusting roller group and the plate strip is 0.1, when the average pressure of the plate strip on the roller surface of the tension adjusting roller group is 1000N, the friction resistance borne by the plate strip is 100N, when the tension adjusting roller group is 5 rollers, the total friction resistance is 500N, and the front and rear tensions of the plate strip between the rolling mill 1 and the subsequent rolling mill 3 are 3500N and 4000N respectively. In addition, the adjusting roller can also provide braking torque or driving torque by a torque controller to adjust the front and back tension between the frames. For convenient operation, the tension adjusting roller group can be composed of a lower roller 6 and an upper roller 7 which can move up and down in a cantilever type, when the plate strip 2 forms continuous rolling between the rolling mill 1 and the next rolling mill 3, the upper roller 7 moves downwards to adjust the distance between the upper roller 7 and the lower roller 6, thereby achieving the adjusting effect of adjusting the friction resistance and the tension between the frames.

See fig. 6, the utility model discloses cantilever type frame tension allotment roller set structure sketch map, torque controller 5 are with controlling last roller 7, can remove from the frame within a definite time, convert normal rolling state into, and lower roll 6 descends to be less than the rolling line behind the height during normal rolling, does not contact with slab band 2.

See fig. 3, the utility model discloses a rolling tension allotment device is arranged in the hot continuous rolling in-process of steel band, when the hot continuous rolling of Q235 steel band, the rolled piece is 200mm wide, 2.0mm thick, rolling mill exit temperature is 900 ℃, because there is water-cooling and to the air heat transfer in the rolling process, when belted steel gets into next rolling mill, the temperature drops to 880 ℃, the yield strength of belted steel this moment is 65MPa and 75MPa respectively, for the tension allotment that obtains preceding tension is 10MPa and back tension is 20MPa, it can to set up the resistance that the resistance is 10000N between the frame.

The above embodiments are merely specific examples selected for the purpose of illustrating the objects, technical solutions and advantages of the present invention in detail, and all modifications, equivalents and improvements made without departing from the spirit and principles of the present invention should fall within the protection scope of the present invention.

Claims

1. A tension adjusting device for rolling magnesium alloy thin strips is characterized in that a tension adjusting roller set is arranged between two adjacent rolling mills; the tension adjusting roller group comprises an upper roller and a lower roller, and the number of the upper roller and the number of the lower roller are the same or different; the number difference of the upper rollers and the lower rollers in the tension allocating roller group is 1; the driving motor of the upper roller or the lower roller is connected with a torque controller; the tension blending roller set is arranged on the closed type or cantilever type structural frame, and the distance between the upper roller and the lower roller is adjustable.