JPS5926362B2 - continuous rolling mill - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a continuous rolling mill, and more specifically, the peripheral speed of two work rolls is changed so that the peripheral speed of the slower work roll is changed to the inlet plate speed, and the peripheral speed of the faster work roll is changed to the inlet plate speed. This invention relates to a continuous rolling mill that makes it possible to roll wide materials by controlling the speed to match the exit plate speed.

In the rolling of metal sheets, reducing the rolling load is necessary for downsizing the rolling mill, reducing roll wear, rolling hard materials, reducing edge drops, etc. This is particularly important for metallic materials.

In normal rolling of a metal plate, there is a method in which a metal plate C is rolled by two work rolls a and b having the same diameter and constant speed.

In this rolling state, the peripheral speeds of work rolls a and b are equal, so the points where the speed of the plate and the peripheral speed of the rolls match, that is, the neutral points N and N2, are on the same vertical line, and the roll bite shown with diagonal lines Frictional force in the direction of the arrow is applied from the work rolls a and b on the plate in section C. Therefore, plate C receives a compressive force in the horizontal direction, and the rolling load in the vertical direction is higher than when there is no frictional force. There is a problem with becoming.

Further, FIG. 2 shows a state in which rolling is performed while changing the circumferential speed of work rolls a s b, and the circumferential speed of work roll b is (■).

, peripheral speed v0 of work roll a, thickness of plate C on the entrance side.

, when the exit side plate thickness h1 of plate C is assumed, the circumferential velocity ratio V1/v
This is a method of rolling under the condition that o is v1/Vo>ho/h1 with respect to the plate thickness ratio.

In this method, the neutral points N1 and N2 are at different positions for the upper and lower work rolls a and b and are on the contact arc, so the direction of the frictional force shown by the arrow on the rolled plate C is on the upper and lower contact arc. There is a part C' that is in the opposite direction and is not compressed in the horizontal direction, and there are only parts on both sides of this part C' that are related to the same frictional force as in the case of normal rolling as shown in Fig. 1. The load is reduced compared to the case shown in FIG.

Recently developed RD (Rolling Drawin)
g) According to the rolling method, the rolling load can be significantly reduced and the above requirements are satisfied.

That is, in this RD rolling method, the circumferential speeds of work rolls a and b are changed, and the circumferential speed of work roll b is set to v.

, peripheral speed of work roll a ■1, thickness of plate C on the entrance side.

, outlet plate thickness h1 of plate C, and inlet plate speed V.

, exit plate speed ■, then V.

-vo1v1=v1, and rolling is performed so that v0/vo-ho/h.

In this case, the neutral points N1 and N2 are at different positions for the upper and lower work rolls a and b, with the neutral point N1 of the lower speed work roll b being at the rolling inlet, and the neutral point N2 of the higher speed work roll a being at the rolling exit. Since the direction of the frictional force is opposite over the entire length of the upper and lower contact arcs, the plate being rolled is not compressed in the horizontal direction (therefore, the rolling load is not affected by the frictional force). (The rolling load can be significantly reduced, and the above-mentioned needs can be satisfied.

However, in the RD rolling method, it is difficult to fix the neutral points N1°N2, so as shown in FIG. The above V is applied by utilizing the frictional force acting between the metal plate C of the winding part and the upper and lower work rolls a and b.

-v. , (2) The condition of 1-v0 is achieved.

In this way, plate C is placed on work roll a. If rolled around b, the tension at the entrance of the two-high rolling mill will be t.

and outlet tension t1 are constant, the inlet tension tb and outlet tension tf of roll bite section Friction coefficient e between the metal plate C and the metal plate C: Since it can vary within the range of the base of the natural logarithm, rolling is stabilized by automatic plate thickness adjustment using tension in response to roll eccentricity and other various disturbances, and lower work roll b peripheral speed V.

, the peripheral speed v1 of the upper work roll a, and the thickness of the lower side (inlet side) of the metal plate C.

, the upper (output side) plate thickness h1, then V as above
1/vo-ho/h, the direction of the frictional force acting on the upper and lower surfaces of the roll bit part can get.

However, in the RD rolling method, the metal plate is wound around the rolls and rolled as described above, so in the case of a tandem roll rolling mill, the shape is as shown in FIG. 5.

d is a roll, e is a metal plate, f is an uncoiler, and 1g is a recoiler.

Therefore, b) Difficult to thread the board; Mouth) Because the backing roll cannot be tightened, the roll is easily bent.

There are disadvantages such as → it is difficult to control the rolling force and → the plate is prone to scratches.

The present invention aims to provide a continuous rolling machine that can perform continuous rolling as in the RD rolling method (by significantly reducing the rolling load) without winding the plate around the rolls as in the above-mentioned RD rolling method. In seven rolling mills, the circumferential speed ratio of the rolls is equal to the elongation ratio of the plate to be rolled, and the circumferential speeds are different.
A device that detects the outlet plate speed of the stand, a device that controls the peripheral speed of the faster work roll of the stand to a set speed, and the signals from each device are compared and the outlet plate tension is adjusted so that the speed difference becomes zero. a device for detecting the inlet plate speed of the stand, a device for controlling the peripheral speed of the slower work roll of the stand to a set speed, and comparing the signals from each device to detect the speed difference. The rolling mill is equipped with a device for adjusting the inlet plate tension so that the tension becomes zero, and is characterized in that it comprises a device for adjusting the inlet plate tension so that the tension becomes zero. The present invention is characterized in that the speed of one of the work rolls having the same circumferential speed in adjacent stands is controlled, and the tension of the other is controlled.

An embodiment of the present invention will be described below with reference to FIG.

1 is an uncoiler, 12 is a recoiler, 3 is a rolled material, 4 and 5 are upper and lower work rolls of the first stand S□, 6 and 1 are upper and lower work rolls of the second stand S2, 8 and 9 are n-th work rolls. Upper and lower work rolls of stand Sn, 10
is a pinch roll, 11 is a board speedometer, 12 is a board speedometer at the exit of the first stand S1, 13 is a board speedometer at the exit of the second stand S2, 14 is a deflector roll, and 15 is a board speedometer at the exit of the in-stand Sn. , 16 is a tension meter on the entrance plate of the first stand S□, 11 is a tension meter between the first and second stands S, S2, 18 is a tension meter between the n-th stand Sn and the stand in front of it, and 19 is a tension meter between the n-th stand Sn and the stand in front of it. Tension meter between n stand Sn and coiler 2, 20 is tension controller of uncoiler 1, 21
is a tension controller, and the tension controller 21 and tension meter 11 control the circumferential speed of the work roll 6 so that the plate 3 between the first and second stands S, S2 has a predetermined tension.

22 is a tension controller which controls the peripheral speed of the work roll 8 using a tension meter 18 so that the plate 3 between the n-th stand Sn and the stand in front thereof has a predetermined tension.

23 is a circumferential speed regulator of the work roll 4 of the first stand S0, which controls the motor using a speed control device and a speedometer to set the set speed.

It's like you want to control it.

24 is a speed signal V from the circumferential speed regulator 23;

and the board speed meter 110 signal, i.e., the detected board speed V.

25 is a comparator that compares the signals with the signals of If the tension correction of 25 times is excessive and exceeds this limiter, the lowering device 27 of the first stand S1 is activated to correct the speed difference.

Reference numeral 28 denotes a circumferential speed regulator for the work roll 5 of the first stand S1, which is designed to control the set speed to Vl, which is faster than the work roll 4.

29 is a comparator that compares the speed signal v1 from the circumferential speed regulator 28 and the signal from the board speed meter 12, that is, the signal of the board speed V1 at the exit of the first stand S□; When there is a speed difference, a calculator 31 converts this into tension and supplies it to the tension controller 21, and 31 is a limiter, and when the tension correction from the calculator 30 is excessive, the first
The lowering device 27 of the stand S1 and the lowering device 32 of the second stand S2 are operated to correct the speed difference.

33 is a circumferential speed regulator that controls the set speed of the work roll 7 of the second stand S2 to 2; 34 is a speed signal v2 from the circumferential speed regulator 33 and a signal from the plate speed meter 13, that is, the output plate speed v2; A comparator 35 compares the speed with the signal, and if there is a speed difference, converts it into tension and applies it to the tension controller (nth) of the next stand.
In the case of stand Sn, a computing unit supplies the tension controller 22); 36 is a limiter 137 similar to the limiter 31 described above; 38 is a circumferential speed regulator that controls the set speed Vn of the work roll 9 of the n-th stand Sn; 39 is a comparator that compares the speed signal Vn from the circumferential speed regulator 37 and the signal from the outlet plate speed meter 15, that is, the signal of the outlet plate speed vn. 41 is a limiter, which converts the tension into tension and supplies it to the tension controller 40 of the recoiler 2. When the tension correction amount from the calculator 3 becomes excessive, the nth stand S
The lowering device 42 of n is operated to correct the speed difference.

The rolled material 3 is uncoiled from the uncoiler 1, passes through the pinch rolls 10, and is transferred to the upper and lower two crawl rolls 4,
5, and the upper and lower work rolls 6 of the second stand S2
．． It is further rolled at 7, then sent sequentially and rolled by upper and lower work rolls 8.9 of the n-th stand Sn, passed through a deflector roll 14, and then wound up by a recoiler 2.

The continuous rolling mill of the present invention basically makes the circumferential speed ratio of the upper and lower work rolls of each stand equal to the elongation ratio of the plate, makes the inlet plate speed equal to the slow work roll circumferential speed, and sets the outlet plate speed to the fast work roll. By keeping the relationship equal to the circumferential speed, the neutral point is located at the rolling entrance on the slow work roll side, and the neutral point is located at the rolling exit on the fast work roll side, similar to the condition of the neutral point in RD rolling shown in Fig. 3. Rolling is carried out in a manner that satisfies the following conditions.

Expressing the above relationship in a formula, we get In the first stand, λ1=■1/vo=v1/v.

=ho/h1 and vl-vl, vo=V.

At the second stand &ζλ22v2/v0=v2/v1-h
1/h2 and v2-v2, vl-v1 at the i-th stand &
ζλi2v i/v 1-0=Vi/Vi-□=h i
−1/h i and vi=Vi, v 1-1=Vi −
0 However, i = 1.2...n λi The elongation ratio of the plate of the second i-th stand vi ``Exit plate speed'' of the plate speed vi- to Vi ``Fast work roll circumferential speed〃 Vi-, : The outlet plate thickness at a slow work roll circumferential speed hi `` `` hi-1: becomes the inlet plate thickness.

That is, the continuous rolling mill of the present invention detects the plate speed at the exit of each stand so as to maintain the above relationship, and compares it with the circumferential speed of each stand's work roll until the difference is zero (or the ratio is constant). In this method, the tension before and after the stand is controlled so that the neutral point is located in the same way as in RD rolling.

Furthermore, as mentioned above, the speed relationship between the work roll and the plate (in other words, the circumferential speed of the work roll and the plate speed exactly match, which is expressed by the so-called neutral point, is the point at which the rolling material It is determined from the balance of forces.

Now, as shown in Fig. 6, the circumferential speed of the upper work roll is vl and the circumferential speed of the lower work roll is V, as in Fig. 3.

, the plate speed on the entry side is V. , the plate speed on the exit side is vl, and the plate thickness on the inlet side is .

, when the plate thickness on the exit side is h0, v□〉vo1■
,〉volho >h, and vl /vo -vl
/vo-h.

When rolling to satisfy the relationship /h1,
FIG. 6A shows a case where 1f is large or tb is small among the plate tensions tf1 and tb acting from the outside.

In this case, since the rolled material (ζ is in the direction of being pulled toward the exit side), the neutral point N2 on the exit side comes into the roll gap so that the total force within the roll gap becomes a dog on the input side.

Figure 6 B&i. This is a case where tf is small or tb is large and the total external force is large in the entry side direction. In this case, the neutral point N1 on the entry side comes within the roll interval.

In this way, the present invention makes the plate speed on the exit side match the circumferential speed of the high-speed roll by changing the tension, so that the neutral point N2 of the high-speed roll comes to the rolling exit, and also The plate speed on the side and the circumferential speed of the low-speed roll are made to match, so that the neutral point N1 of the low-speed roll comes to the rolling entrance.

In order to carry out such control, it is necessary to install a device to adjust the tension, a tension value limiter or a tension meter to prevent the tension value from exceeding the limit, and even change the circumferential speed of the work roll to increase the stand. and to control the tension between them.

Next, to explain specifically, the uncoiler 1 shown in FIG.
and the first stand 81, the plate speed V on the entrance side of the first stand S1.

is detected by the plate speed needle 11, and the speed signal v of the slower work roll 40 peripheral speed regulator 23 of the first stand S1
o and the plate speed V above.

If there is a speed difference, the speed difference is converted into tension by the calculator 25 and supplied to the tension controller 20, so that the inlet plate tension to the uncoiler 1 reaches the set value. The uncoiler 1 is controlled so that the speed difference becomes zero (
or the speed ratio is constant).

Since the uncoiler 1 is controlled in advance so that the tension becomes a predetermined value by the tension controller 20 which receives the tension setting signal Tb and the tension signal from the tension meter 16, the tension correction signal from the arithmetic unit 25 is applied. Accordingly, the plate tension on the entry side of the first stand S1 is adjusted so that the speed difference becomes zero, and the vo-vo is controlled.

Thereby, the same neutral point N1 as the neutral point in the case of RD rolling shown in FIG. 3 can be obtained.

In the tension correction described above, if the tension correction signal is too thick, the limiter 26 corrects the reduction of the reduction device 27 of the first stand S1, and control is performed so that the tension correction signal falls within the limit of the limiter 26. is performed and the speed difference is corrected.

Next, between the first stand S1 and the second stand 82,
The circumferential speed of the faster work roll 50 of the first stand S1 is controlled to vl by the circumferential speed regulator 28. The comparator 29 compares the signal of the plate speed v1, and if there is a speed difference, the difference is converted into tension by the calculator 30 and supplied to the tension controller 21 to correct the tension of the outlet plate.

The slower work roll 6 of the second stand S2 is connected to the tension controller 2 to which the tension setting signal Tf1 is input.
1 and a tension meter 17 to control the circumferential speed so as to maintain the tension between the first and second stands S1 and 82 at a predetermined value.
When the tension controller 21 receives the tension correction from the calculator 30 as described above, the circumferential speed of the work roll 60 of the second stand S2 is controlled, the plate tension on the exit side of the first stand S1 is adjusted, and the tension of the work roll 60 of the second stand S2 is adjusted. Circumferential speed v0 of work roll 5 of S1 and plate speed v0 on the exit side of first stand S1
is controlled so that the difference between the two is zero.

As a result, the same neutral point N2 as shown in FIG. 3 can be obtained.

At the same time, the work roll 60 circumferential speed v of the second stand S2
1 also the plate speed v1 between the first and second stands S1, 82
is controlled equally.

When the above-mentioned tension correction signal is excessive, the limiter 31 controls the lowering device 27 of the first stand S1 and the second stand S1.
The tension correction signal is controlled to fall within the limits of the limiter 31 by correcting the reduction of the second reduction device 32.

In this way, control is sequentially performed up to n stands Sn.

Between the n-th stand Sn and the coiler 2, the peripheral speed of the faster work roll 9 of the n-th stand Sn is detected by the speed signal Vn of the peripheral speed regulator 31 and the exit plate speed meter 15. A comparator 38 compares the signal of the outlet plate speed vn, and if there is a speed difference, the difference is calculated by a calculator 39.
is converted into tension and supplied to the tension controller 40, which controls the recoiler 2 to correct the outlet plate tension.

If this tension correction amount becomes excessive, the limiter 41 sends a signal to the rolling down device 42 of the n-th stand Sn to correct the rolling down and adjust the exit plate tension so that the speed difference becomes zero.

As described above, the difference between the inlet plate speed of the stand and the slower work roll circumferential speed of the stand is zero, and the difference between the outlet plate speed and the faster work roll circumferential speed is zero. Since rolling is performed by adjusting the tension on the exit side, the neutral point N1 of the slower work roll and the neutral point N2 of the faster work roll of the stand are R as shown in Figure 3.
The same neutral point relationship as in the case of D rolling is obtained, and continuous rolling can be performed in the same manner as in RD rolling.

Note that the continuous rolling mill of the present invention is not limited to the above-mentioned embodiments, and the work roll for tension control may be a slow work roll on the stand, or a work roll with a fast circumferential speed on the front stand. In this example, when the tension correction amount exceeds the limiter, a signal is sent to the tension device on the stand to correct the pressure reduction. It is also possible to modify the rolling down device through the tensioner, or to apply tension to a work roll with a slow circumferential speed as in the configuration from the second stand S2 onwards. The rolling mill may be configured such that a work roll with a high circumferential speed of 111 m is set at a speed of II) Ill.

As described above (according to the continuous rolling mill of the present invention, (i) R
RD rolling method without wrapping the plate around a roll as in the D rolling method.
Continuous rolling can be performed similarly to the rolling method.

(ii) The above (i) eliminates all the drawbacks when winding a plate around a roll.

(iii) By providing a tension correction signal or a tension signal limiter and correcting the reduction device when this signal exceeds the limiter, reliable cutting is possible and there is no risk of cutting the plate.

It can produce excellent effects such as

[Brief explanation of drawings]

Figure 1 is a diagram of normal rolling using work rolls with equal diameter and constant speed, Figure 2 is a diagram of rolling when the circumferential speed ratio of the upper and lower work rolls is changed, and Figure 3 is a diagram of rolling by the RD rolling method. State diagram, Figure 4 is an explanatory diagram of the RD rolling mill, Figure 5 is the RD rolling mill.
An explanatory diagram of a tandem roll rolling mill using the rolling method, Figures 6A and B are schematic diagrams showing the operation of the continuous rolling mill of the present invention, Figure 7
The figure is a schematic diagram showing an example of a continuous rolling mill of the present invention. 1...Uncoiler-12...Recoiler, 3...
Rolled material, 4, 5, 6, 7, 8, 9... work roll,
11.12.13.15... Plate speed needle, 16, 17° 18.19... Tension meter, 20, 21, 22... Tension controller, 23... Peripheral speed regulator, 24...
... Comparator, 25 ... Arithmetic unit, 26 ... Limiter
127... Reducing device, 28... Peripheral speed regulator, 29... Comparator, 30... Arithmetic unit, 31... Limiter 132... Reducing device, 40... Tension controller.

Claims (1)

[Claims] 1. In a rolling mill in which the circumferential speed ratio of the upper and lower work rolls is equal to and different from the elongation ratio of the rolled plate, there is provided a device for detecting the exit plate speed of the stand, and a device for detecting the outlet plate speed of the stand, and a device that controls the circumferential speed of the work roll to a set speed;
A device that compares the signals from each device and adjusts the outlet plate tension so that the speed difference becomes zero, and a device that detects the inlet plate speed of the stand, and a device that detects the peripheral speed of the work roll of the slower one of the stands. A rolling mill comprising at least one rolling mill equipped with a device for controlling the rolling speed to a set speed, and a device for comparing the signals from each device and adjusting the tension of the inlet plate so that the speed difference becomes zero. Continuous rolling mill with special features. 2. In a rolling mill in which the circumferential speed ratio of the upper and lower work rolls is equal to and different from the elongation ratio of the rolled plate, a device for detecting the outlet plate speed of the stand and a device for setting the circumferential speed of the faster work roll of the stand are used. a device for controlling the speed;
A device that compares the signals from each device and adjusts the outlet plate tension so that the speed difference becomes zero, and a device that detects the inlet plate speed of the stand, and a device that detects the peripheral speed of the work roll of the slower one of the stands. A device for controlling the speed to a set speed, and a device for comparing the signals from the respective devices and adjusting the tension of the entrance plate so that the speed difference becomes zero, and further comprising a signal for correcting the tension of the exit plate or limiting the tension signal. At least one rolling mill is equipped with a tension meter on the exit side and is capable of controlling the rolling device of the stand to be within the limit by correcting the rolling device of the stand when the signal exceeds the limit of the limiter. A continuous rolling mill characterized by comprising the above. 3. In a rolling mill in which the circumferential speed ratio of the upper and lower work rolls is equal to and different from the elongation ratio of the rolled plate, set the circumferential speed of the high-speed side work roll of the stand on the upstream side of the rolling line among the adjacent stands. a device for controlling the speed, a device for detecting the plate speed between adjacent stands, and a tension control device for controlling the inter-stand tension by changing the circumferential speed of the low-speed work roll of the downstream stand of the rolling line; and a device for detecting tension between the stands, which compares the circumferential speed of the high-speed work roll of the upstream stand and the plate speed between the stands, and controls the tension between the stands so that the speed difference between the two becomes zero. A continuous rolling mill characterized by: