JPS6117327A - Method and device for tension generation of strip - Google Patents

Abstract

PURPOSE:To make the diameter of a roller smaller by providing a bending device on the strip rolling out side of one of the two driven rollers passing through with a strip being coiled. CONSTITUTION:A strip 11 is wound on a pair of bridle rollers 14, 16 and in made to be bent in the reverse direction to the direction bent by the bridle roller 16 by a bending roller 18 provided close to the bridle roller 16, after its passing through the bridle rollers 14, 16. The bend deformation of the strip 10 by the bridle rollers 14, 16 is therefore corrected and the diameter of the bridles 14, 16 can be made smaller.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Application of the Invention] The present invention relates to a method and apparatus for generating tension in a strip when tension is applied to the strip and the strip is rolled or bent and stretched, and particularly relates to a tension generation method using a tension pridle type. and related to equipment.

[Background of the invention]

Examples of processing a strip by applying tension to a band-shaped strip can be seen in many cases such as rolling, tension leveling by bending and stretching the strip, and scale breakers. As a method of applying tension to the strip, as seen in JP-A-53-118227 (hereinafter referred to as the known example), two or more rollers are arranged before and after a bending/stretching machine, and the strip is applied to each roller. A device called a tension pridle is used, which uses the frictional force between the roller and the strip to apply high tension. In the case of a rolling or tension leveler, a rolling mill or a leveler is provided in place of the bending and stretching machine of the above-mentioned known example.

In these rolling machines or the mechanical scale prefabricated machines mentioned above, especially when handling strips with a large thickness,
Since it is desired to stretch the strip to a large extent, it is desirable to apply a large tension to the strip.

In the known example, since it is difficult to apply a large tension with a prydle device, it has been proposed to provide a device such as an intermediate prydle. However, if a greater tension can be applied to the bridle device, such an intermediate bridle roller can be eliminated9, providing an economical device. In other words, if a scale breaker can generate a bending elongation rate of 1096 or more in the strip, cracks will occur in the scale due to the difference in elongation rupture rate with the scale base material, and 70 to 80 inches of scale will need to be treated with a scale breaker. It can be removed in just one step, and the subsequent pickling process can be done in a very short time (compared to 115 times in the past). Nevertheless, the bending elongation of the strip in conventional scale breakers is limited to approximately 5 inches or less. This is due to the following reason.

The maximum dimensions of the strip processed by the scale breaker are approximately 5mm thick and 1650mm wide.

When the plate thickness is as thick as 5 m, the diameter of the bridle roller is empirically determined to be 160011II11, as detailed later.
A certain degree is used. A strip tension of 50 tf is required to bend and stretch the above plate by 5%. However, in order to further increase the elongation to about 10%, a large tension of 100 tf is required since the elongation of the strip and the tension are approximately proportional.

Meanwhile, as shown in FIG.
When the strip is wrapped around and bent, stress occurs in three directions on the strip surface. That is, when tension is applied in the longitudinal direction of the strip, not only does an elongation strain ε□ occur, but also strains εh and εh occur in the width and thickness directions, respectively. The following equation holds between these distortions.

, εt+eb+εh=o ・・・・・・
(1) Generally, in plastic deformation, t = g), so a strain of 61' occurs in the width direction of the plate.

On the other hand, the strain εt in the longitudinal direction is determined by the roller diameter being D1 and the plate thickness being h.
Then, ε゛ is medium h/l) ・・・・・・(
2). Therefore, εb+−h/2D (3
).

If the longitudinal elastic modulus of the strip is E, a stress σb of BIb is generated in the width direction of the strip surface.

It can be seen that when this stress exceeds the yield stress σ of the strip, plastic deformation also occurs in the strip width direction.

FIG. 7 shows the strain εb at the position of the inner pot in the width section of a strip bent with a radius of curvature D/2. However, in reality, even if the strip is bent in the longitudinal direction, the strip is pressed against the roller and is regulated by the roller in the width direction of the breast plate.
It cannot bend and is in a state of zero curvature, and the widthwise strain εb occurs in a plane strain state. That is, the side of the strip in contact with the roller has a negative strain (-εb), and the opposite side has a positive strain εb. When Eεb exceeds the material yield stress σ, plastic deformation occurs from the strip surface. When plastic deformation occurs in this way, the part bent by the rows 212 in FIG. When it is bent, it undergoes a curved deformation as shown by symbol A. When this curved deformation occurs, it is not only difficult to pass the strip past the bridle roller, but also to ensure the uniformity of the surface treatment effect, especially when surface treatment processes such as pickling and plating are performed subsequently. The above is the problem. In particular, when the diameter of the roller becomes smaller, εb becomes larger as shown in equation (3), and curvature deformation is likely to occur. Therefore, in order to keep EE'b within the elastic limit, it is necessary to select the roller diameter as follows.

Therefore, if E = 21000 blows and h = 5-σ1 = 32 chest/゛-2, then from equation (5), p = 1640 pounds.

As mentioned above, the diameter of the bridle roller is the same as described above (approximately 1600 mm) when processing plates with a thickness of 5 mm, and strip breakers with high bending and elongation ratios have not been put to practical use in the past. .

However, as the bridle roller diameter increases, the product of the tension generated and the roller radius becomes the drive torque, so the drive torque increases in proportion to the roller diameter, and the drive system equipment is enormous. Ru.

[Purpose of the invention]

SUMMARY OF THE INVENTION An object of the present invention is to provide a method and apparatus for generating tension in a strip, which can reduce the diameter of a roller that applies tension to the strip.

[Summary of the invention]

The present invention involves re-bending the strip in the opposite direction to the direction in which it was bent by the rollers that the strip passes as it is being wound;
The present invention is configured to correct the curved deformation of the strip caused by the two or more rollers, and to reduce the diameter of the two or more rollers.

[Embodiments of the invention]

A preferred embodiment of the method and device for generating tension in a strip according to the present invention will be described in detail with reference to the accompanying drawings.

FIG. 1 shows the principle of the method and device for generating tension in an IJ tube according to the present invention. In FIG. 1, the strip 10 is wound around a pair of bridle rollers 14.16, and after passing through the bridle rollers 14.16, the strip 10 is placed adjacent to the bridle rollers 16 on the strip delivery side of the pridle row 216. The bending row 218 causes the bridle roller 16 to bend in the opposite direction to the bending direction.

The strip 10 is formed by the bridle roller 16 as shown in FIG.
t = 1/R1). Then, when the bending moment M is released during the strip feeding position of the bridle roller 16, M=0, a residual curvature ' occurs in the width direction of the plate, and the plate curves. Therefore, as shown in FIG. 1, a bending row 218 is provided on the strip delivery side of the bridle roller 16 in close proximity to the bridle row 216.
As shown in FIG. 2, the curvature is corrected by bending in the opposite direction by 2t. At the point where the strip 10 exits from the bending row 218, the curvature of the strip 10 becomes zero due to springback, the curvature deformation is corrected, and the diameter of the priddle row 914.16 can be reduced. In addition, the relationship between Kl and 2 is generally K
s>Ks.

As described above, the present invention employs a small-diameter bridle roller, but the bending deformation in the board width direction caused by the bridle roller K is corrected by the bending roller 18 provided immediately after the bridle roller 16. From then on, the plate is not curved and normal strip threading is possible.

Further, by providing the bending row 218, the following additional effects can be obtained at the same time. That is, the tension that can be generated by one priddle row 2 is expressed by the following formula: % where σ0 is the inlet tension, σ1 is the outlet tension, θ is the winding angle, and μ is the friction coefficient. According to this formula (6), if the angle θ becomes a dog, the tension σ1 that can be generated can be increased. Therefore, the bending roller 18 provided on the strip sending side of the bridle roller 16 increases the winding angle by Δθ, making it possible to increase the tension σ1.

That is, in the case where there is no conventional bending row 218, the winding angle is θ2.
is generally 220 degrees, but the installation of the bending row 218 increases the winding angle by Δθ=30 degrees.

If μ = 0.15, σ1/σ0 is conventionally σ1/σo = 7.78, but in this example it increases to σ1/σ0 = 923. . That is,
This has the effect of increasing the tension generation magnification with one roller.

Note that when the diameter of the bridle roller 16 shown in FIG. For example, the problem of strength against tension can be satisfactorily solved.

FIG. 3 shows a specific example of the tension generator according to the present invention. In FIG. 3, the stand 20 of the rolling mill is provided with an upper working row 222 and a lower working row 224, so that the strip 10 can be rolled.

On the strip 10 person side of the stand 20 (on the left side in FIG. 3), there are entry side bridle rollers 26, 28, 3.
0°32 is provided, and an exit bridle roller 3 is provided on the exit side.
4.36, 38, and 40 are arranged. Inlet bridle roller 28.32 and outlet bridle roller 236.40
Bending rollers 42, 44.degree. 46.48 of a bending device are respectively provided on the strip delivery side.

The power transmission system of the entry side bridle rollers 26.28, 30.32 includes gears 50, 52,
54, 56 meshing, and gear 58 that further collects this
, 60 are assembled on one shaft and connected to a direction changing bevel gear 62. Output side bridle roller 34, 3
6.38゜40 power transmission system has gear 6 as well as the input side.
4°66.68.70 meshing, and are further assembled into one shaft by gears 72 and 74, and connected to a bevel gear 76. The power for the entry and exit side priddle rolls is supplied to the motor 68. In addition, the tension between the priddles on the input side and the output side is determined by controlling the torque of the motor 86 by driving a gear 82 attached to a case 8o that holds the differential gear 78 via a pinion 84. It is given by doing.

The lowering mechanism of the bending roller, that is, the bending device is shown in FIG. 4, taking the bending row 248 as an example. The priddle row 238.40 is attached to the frame 90 by the bearing box 88 or the like.

Then, the bending row 2 for the exit bridle roller 40
48 is provided on the arm 96 via a pin 94 attached to a bracket 92, and by pressing down on the cylinder 98, the strip 10 is bent in the opposite direction to the bridle roller 40. The cylinder 9B is supported by a bottle 100 provided on the pedestal 90 and a bottle 102 provided on the arm 96.

The amount of reduction of the roller 48 is adjusted by vertically adjusting the screw 106 with respect to the bracket 104 provided on the pedestal 90. Of course, this screw 106
It is also possible to automatically adjust the plate thickness by detecting the plate thickness using a plate thickness detector (not shown) and driving a drive device such as a motor via a control device (not shown). In addition,
Of course, this adjustment is not necessary when the plate thickness does not change much.

Note that the bending roller is not provided on the strip delivery side of all the slider rollers.

The reason for this is that, for example, the distance between the entry side bridle roller 26 and the entry side bridle 2 is not necessary because the distance between the rollers is short and the strip 10 is unlikely to be bent in the width direction.

This is the five rows shown in Figure 5. 108°11
The same applies to vertical bridle rollers constructed of 0.112, 114, and 116. That is, since the spacing between the plywood rows 2108 to 116 is narrow, curvature deformation is unlikely to occur.

In such a case, it is only necessary to provide the bending row 2118 on the exit side of the roller 116 on the removal side of the strip 10. In addition, in order to improve the bending effect of the bending row 2118,
Auxiliary rows 2, 20 may also be provided.

According to the above embodiment, for example, the thickness is 5 mm and the plate thickness is 165 mm.
Assuming that tension is applied to a strip of 0 m5, the inlet bridle rollers 26.28, 30.32 and the outlet bridle rollers 34, 36, 38.40 are solid rollers with a diameter of about half the conventional diameter, i.e., 750 mm in diameter. is used. Since the roller diameter is thus small, a curved deformation occurs in the strip width direction of the strip 10 on the exit side of the prydle row 2, as shown in FIG. Thereupon, the strip 10 is bent by bending rollers 42, 44, 46, 48.
8. Perform the work of bending in the opposite direction to 32, 36. 40,
Correct the curved deformation that occurs in the width direction of the plate. in this way,
In this embodiment, the diameter of the bridle roller can be made smaller, so even if twice the tension is applied than before, the driving torque can be kept at the same level as the conventional one. It can be made into a value.

In addition, in the above-mentioned embodiment, the rolling mill was arranged between the input side and exit side priddles, but a descaler with rollers arranged in a staggered manner as shown in the above-mentioned known example was arranged, It is also possible to bend and stretch the strip to break up any skeletal particles stuck to the surface of the strip.

〔Effect of the invention〕

As explained above, according to the present invention, it is possible to reduce the diameter of the roller that applies tension to the strip.

[Brief explanation of drawings]

FIG. 1 is an explanatory diagram showing the principle of the tension generation method and tension generation device for a strip according to the present invention, FIG. ) FIG. 4 is a block diagram of an embodiment of a tension generating device for IJ tubes, FIG. 4 is a schematic diagram of an embodiment of a bending roller rolling mechanism, and FIG. 5 is a diagram showing another embodiment of a strip tension generating device according to the present invention. FIG. 6 is an explanatory diagram of the curved diamond shape of the strip produced by the small-diameter bridle roller, and FIG. 7 is an explanatory diagram showing the occurrence of stress and potholes in the cross section of the strip in the width direction of the strip in the small-diameter bridle roll. . 10... Strip, 14.16... Bridle roller, 18, 42, 44, 46, 48, 118... Bending roller, 26, 28, 30, 32... Entry side bridle roller, 34, 36 , 38, 40... Exit bridle roller, 96... Arm, 9B... Cylinder, 1
04... Bracket, 1o6... Screw, 12°... Auxiliary roller.

Claims (1)

[Claims] 1. A strip tension generation method in which a strip is wound around two or more driven rollers and tension is generated by contact friction between the roller surface and the strip surface, wherein the strip of at least one of the rollers 1. A method for generating tension in a strip, which comprises bending the strip in a direction opposite to the direction in which the roller bends the strip on the feeding side. 2. The re-bending of the strip is performed near the delivery portion of the roller through which the strip of the two or more rollers passes last.
Method of generating tension in strips as described in Section. 3. The method for generating tension in a strip according to claim 1 or 2, wherein the bending amount of the strip is changed in accordance with the thickness of the strip. 4. In a strip tension generating device comprising two or more rollers through which the strip passes while being wound, and a drive source for rotationally driving these rollers, at least one of the rollers has this on the strip delivery side. 1. A tension generating device for a strip, comprising a bending device having a bending roller that bends the strip in a direction opposite to the direction in which the strip is bent by the roller. 5. The strip tension generating device according to claim 4, wherein the bending device is disposed near a delivery portion of a roller through which the strip of the two or more rollers passes last. 6. Claim 4, wherein the bending device includes positioning means for maintaining the bending roller at an arbitrary position, and bending force applying means for pressing the bending roller against the strip. Or the strip tension generator according to item 5. 7. The bending device includes a plate thickness detector that detects the thickness of the strip passing through the two or more rollers, and a position of the positioning means to maintain the bending roller based on a detection signal from the plate thickness detector. 7. The strip tension generating device according to claim 6, further comprising control means for changing the tension.