JP2012224937A - Device for supporting steel strip of acid washing tank - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a device for supporting a steel strip of an acid washing tank in which a roller structure with a skew for preventing meandering can be adapted to a dam roller vulnerable to acid corrosion.SOLUTION: The device for supporting a steel strip in an acid washing tank so that the steel strip continuously carried into an acid washing tank inside of which divided by a dam 2 into at least two acid tanks, is prevented from making contact with the dam 2, includes: an acid-resistant support shaft 11 bent in a direction opposite to a traveling direction of the steel strip at around the center of the width; and acid-resistant cylindrical sleeves 12, 13 provided rotatably around the bent right and left support shafts 11.

Description

  The present invention relates to a steel strip support device for a pickling tank in which at least two pickling tanks are formed by partitioning the inside by a dam.

Conventionally, pickling treatment has been performed to remove rust, scale, and the like of steel strips.
As such a pickling apparatus, a pickling tank 1 is used as shown in FIG. 9 so that the steel strip can be continuously pickled. The pickling tank 1 is partitioned into a plurality of tanks 3 by a plurality of dams 2 along the traveling direction of the steel strip S. Each tank 3 is filled with an acid such as hydrochloric acid for removing rust and scale attached to the steel strip S carried by the bridle roll 4 provided on the entry side and the exit side of the pickling tank 1. As shown in FIG. 10, the steel strip S is immersed in the acid of each tank 3 over the skid cap 2a at the top of the dam 2 to remove rust and scale attached to the surface (for example, Patent Document 1, FIG. 9, see FIG.

  The dam 2 is made of a material that is not easily affected by acid, for example, a hard material such as acid-resistant brick or stone. . For this reason, some idle rolls that reduce friction with the surface of the steel strip S are provided so that wrinkles are difficult to enter (for example, see Patent Documents 2 and 3).

  By the way, when the steel strip S is immersed in the acid of each tank 3 of the pickling tank 1 and transported to the next tank 3 beyond each dam 2, the steel strip S meanders in a direction perpendicular to the transport direction. A phenomenon occurs. In particular, when an idle roll is provided, meandering tends to be larger than when only a skid cap is provided. The reason for this is that the idle roll has a gap with the shaft to enable rotation, and has a degree of freedom in tilting with respect to the transport direction, but when rotated in a tilted state, the steel strip goes straight to the transport direction. This is because it can cause movement in the direction. If the meandering is large, the steel strip S comes into contact with the structure near the dam 2 such as the end of the idle roll or the horizontal wall of the tank, so that the end face of the steel strip S is damaged or the equipment is destroyed. .

  As a means for suppressing the meandering of the steel strip S, there is known a method for providing a predetermined skew to a pair of rolls that support the lower surface of the steel strip from both sides with a center line interposed therebetween as disclosed in Patent Document 4. . As shown in FIG. 11, the skew is to give an inclination angle in the longitudinal direction of the support rolls 6 a and 6 b in the direction opposite to the traveling direction of the steel strip S with respect to the direction orthogonal to the traveling direction of the steel strip S. The θ shown in FIG. 11 is called a skew angle. Here, as shown in FIG. 11, the pair of support rolls 6 a and 6 b has a traveling direction of the steel strip S with respect to a direction orthogonal to the traveling direction of the steel strip S from the left and right with respect to the traveling direction of the steel strip S. The steel strip S is supported with a skew angle θ in the opposite direction.

  Thus, by installing the direction of the longitudinal direction of a pair of support rolls 6a and 6b in the direction opposite to the traveling direction of the steel strip S (the direction of the white arrow in FIG. 11), the steel strip S is attached. Is always applied with a force directed in the center direction of the steel strip S (the force in the direction of the thin arrow in FIG. 11) and has the effect of suppressing meandering. In addition, when the center position of the steel strip S is shifted due to meandering, a difference is generated in the frictional force between the pair of support rolls 6a and 6b provided on the left and right, and the steel strip S is shifted with respect to the steel strip. A greater force is applied in the direction in which the correction is made, providing a meandering correction effect. In addition, by increasing the skew angle θ, the force directed toward the central direction with respect to the steel strip S becomes stronger.

  The skewed support rolls 6a and 6b proposed in Patent Document 4 are applied to the looper portion at the pickling tank entry side, for example, at the pickling tank exit side and the cold rolling mill entry side looper portion. Is also applicable.

JP-A 63-86882 Japanese Patent Laid-Open No. 10-287989 Japanese Patent Laid-Open No. 11-1786 JP 2005-334949 A

  However, even if a skew angle is provided in the roll of the looper portion on the tank entry / exit side as described above, the meandering generated by the dam roll in the pickling tank cannot be suppressed even if the meandering of the steel strip S in the looper portion can be prevented. Problems such as brazing the end surface of the steel strip S will occur.

  Then, this invention aims at providing the steel strip support apparatus of the pickling tank which can suppress the meandering of the steel strip S in a pickling tank and can prevent the wrinkle of the end surface of the steel strip S. .

  In order to solve the above problems, in the steel strip support device for a pickling tank according to the present invention, the steel strip is continuously fed into a pickling tank in which at least two pickling tanks are formed by partitioning the inside by a dam. Is a steel strip support device in a pickling tank for supporting the steel strip so as not to contact the dam, the acid-resistant support shaft bent in the direction opposite to the traveling direction of the steel strip near the center of the width, and the bent And an acid-resistant cylindrical sleeve rotatably provided around the left and right support shafts of the portion.

  The support shaft may be integrated, but a pair of left and right shaft centers that are attached in a state bent in the opposite direction to the traveling direction of the steel strip on both sides of the bearing block at the center of the width are linear. You may make it the structure which consists of a shaft body. With such a configuration, manufacturing can be facilitated.

  The skew angle of the bent support shaft is preferably 0.6 ° or more and 3 ° or less. If the angle is less than 0.6 °, the meandering correction function is insufficient, and if it exceeds 3 °, the force that pushes the central portion of the sleeve against the shaft becomes strong, making it difficult for the sleeve to rotate, causing uneven wear, short The above-mentioned range is preferable because of the life.

  Further, the support shaft has a structure in which the surface of the iron material is coated with an acid-resistant material, and the surface thereof is further coated with a lubricious material, and the sleeve is coated with acid-resistant rubber on the outer peripheral surface of a cylindrical plastic. It is preferable to have a configuration. The specific method of covering with an acid-resistant material and further covering the surface with a lubricating material may be, for example, an iron material with a rubber lining and a fluororesin intermediate tube fitted and integrated, Thereby, it is hard to be affected by an acid and the friction with a sleeve can be reduced. In addition, the sleeve is made of plastic such as FRP to maintain lubricity with the shaft, and the outer peripheral side surface is covered with acid-resistant rubber, so that the steel strip is less likely to wrinkle. If the material on the outer peripheral side is other than acid-resistant rubber, such as plastic or laminated resin, due to the warpage in the width direction of the steel strip or the unevenness formed by the edge burr generated at the end when slitting in advance, the difference in the threading frequency There is a case where wrinkles are formed on the steel strip due to a wear step generated in the sleeve. The acid-resistant rubber is preferable because even if irregularities and steps are generated, no flaws are generated in the steel strip due to the unevenness or steps.

  Moreover, it is preferable to provide a step part having a diameter larger than the central part in the longitudinal direction on both ends in the longitudinal direction of the inner periphery of the sleeve. The acid solution enters the gap between the stepped portion and the outer periphery of the support shaft, and this acts as a lubricating solution to lighten the rotation of the sleeve.

  Further, the surface of the shaft support block provided at the end portion of the support shaft is vertical on the downstream side in the traveling direction of the steel strip, and the steel strip proceeds on the shaft support block receiver provided on the side wall of the pickling tank. The downstream surface with respect to the direction is preferably vertical. In the present invention, a reaction force acting to push the steel strip of the sleeve having a skew angle toward the center acts as a force to cause the support shaft to pass in the plate direction. This force increases as the skew angle increases. Therefore, in order to receive the force to cause the support shaft to pass in the plate direction, the surface of the shaft support block on the downstream side with respect to the traveling direction of the steel strip is vertical, and the shaft support block support is also in the traveling direction of the steel strip. The surface on the downstream side should be vertical.

  The shaft support block preferably has an inverted trapezoidal shape with a lower side as viewed from the side surface, and the shaft support block receiver also preferably has an inverted trapezoidal shape with the upper part opened. In this way, when the support device is replaced, the support shaft and the sleeve can be removed simply by lifting upward without removing the acid solution from the tank, and a new support shaft and sleeve can be easily attached.

  ADVANTAGE OF THE INVENTION According to this invention, the meandering of the steel strip passed through in the pickling tank can be prevented, and it can prevent that a flaw generate | occur | produces in the edge part of a steel strip.

It is a top view which shows the installation state of the steel strip support apparatus of the pickling tank which concerns on one embodiment of this invention. It is sectional drawing which shows the installation state of the steel strip support apparatus of the pickling tank which concerns on one embodiment of this invention. It is sectional drawing of the steel strip support apparatus of the pickling tank which concerns on one embodiment of this invention. It is an expanded sectional view of the support shaft end part vicinity of the steel strip support apparatus of the pickling tank which concerns on one embodiment of this invention. It is an expanded sectional view of the bearing block vicinity of the steel strip support apparatus of the pickling tank which concerns on one embodiment of this invention. It is a side view of the axis | shaft support block of the steel strip support apparatus of the pickling tank which concerns on one embodiment of this invention. It is sectional drawing of the sleeve of the steel strip support apparatus of the pickling tank which concerns on one embodiment of this invention. It is a figure which shows the relationship between a skew angle and the largest meander generation amount. It is a side view which shows the structure of the conventional pickling tank. It is an enlarged side view of the pickling tank of FIG. It is a top view which shows the effect | action of the support roll which provided the skew.

Embodiments of the present invention will be specifically described below with reference to the drawings.
As shown in FIGS. 1 and 2, the steel strip support device 10 for the pickling tank according to the embodiment of the present invention is installed in the vicinity of the dam 2, and the width center is opposite to the traveling direction of the steel strip S. In the vicinity, it has a support shaft 11 bent at a skew angle θ, and a pair of acid-resistant sleeves 12 and 13 that are rotatably provided on the left and right of the bent portion. Shaft support blocks 14 and 15 are provided at the ends of the support shaft 11, and the support shaft 11 is supported by shaft support block receivers 16 and 17 provided on the side wall 19 of the pickling tank. As shown in FIG. 3, the support shaft 11 is provided with a bearing block 18 near the center of the width of the pickling tank, and shaft bodies 11A and 11B are provided between the shaft support blocks 14 and 15 on the side walls of the pickling tank. It is good also as a structure. The shaft bodies 11A and 11B are installed in a state bent at a skew angle θ in the direction opposite to the traveling direction of the steel strip.

  As shown in FIG. 4, the support shaft 11 is formed by covering the outer periphery of a steel shaft main body 11a with a rubber lining 11b and further fitting a fluororesin cylinder 11c on the outer periphery thereof. The rubber lining 11b provides acid resistance to prevent the steel shaft body 11a from being affected by acid, and the surface friction is reduced by the fluororesin coating 11c. Further, the shaft support blocks 14 and 15 at the end of the support shaft may be made of FRP (fiber reinforced plastic), and the shaft support block receivers 16 and 17 on the side of the pickling tank may be rubber-lined on the main body made of FRP or steel.

  When the bearing block 18 is provided at the center, it is desirable to provide a rubber lining 18b on the surface of the steel main body 18a as shown in FIG. 5 and to fit a fluororesin ring 18c on the side contacting the sleeve to reduce the friction. .

  The sleeves 12 and 13 have acid resistant rubbers 12b and 13b coated on the outer peripheral surfaces of the FRP sleeve bodies 12a and 13a. As the material of the acid resistant rubber, butyl rubber (isobutylene / isoprene copolymer), styrene rubber (styrene / butadiene copolymer), ethylene propylene rubber or butadiene rubber can be used. Further, since the acid-resistant rubbers 12b and 13b are in contact with the surface of the steel strip S, the hardness is JIS K 6253 type A durometer so that the steel strip S is not damaged and is not easily damaged by the steel strip S. It is preferable to use a 50-80 degree thing by a length test.

  The support shaft 11 bent in the vicinity of the center of the width in the direction opposite to the traveling direction of the steel strip S is in a direction to make the shaft perpendicular to the plate direction by the reaction force of the force that corrects the meandering of the steel strip S. A force is received from the steel strip S via the sleeves 12 and 13. Since the skew angle of the support shaft 11 is fixed, it becomes a force for raising the entire shaft with the shaft support blocks 14 and 15 at the end of the support shaft as fulcrums. In order to reduce this force, the shape of the shaft support blocks 14 and 15 is such that the downstream surface in the traveling direction of the steel strip is vertical as shown in FIG. If the surface on the downstream side in the traveling direction is vertical, it is possible to suppress the support shaft 11 from rising.

  As shown in FIG. 6, the shaft support blocks 14 and 15 provided at the end of the support shaft 11 have an inverted trapezoidal shape as shown in FIG. The support block receivers 16 and 17 can be easily attached and detached from above. The shaft support blocks 14 and 15 and the shaft support block receivers 16 and 17 are not fixed by fixtures, but are simply held on the shaft support block receivers 16 and 17 by the weight of the support shaft 11 and the sleeves 12 and 13. is there. Thereby, it can replace | exchange by raising / lowering and moving work by machines, such as a crane, with a short rest time and a small work load, without extracting an acid solution from a tank.

  FIG. 7 shows an example of a cross-sectional shape of the sleeves 12 and 13. This is an example in which stepped portions having a diameter larger than the central portion in the longitudinal direction are provided in the regions a and b on both ends in the longitudinal direction of the inner circumference of the sleeve main bodies 12a and 13a. By providing the step as described above, the acid solution enters the gap between the outer circumferences of the support shafts 10 and 11 and the a and b portions, which acts as a lubricating solution and lightens the rotation of the sleeves 12 and 13.

  Next, the appropriate value of the skew angle θ was examined. The allowable meandering amount in the tank is determined by half of the difference between the steel strip width and the internal dimensions of the tank equipment such as the tank wall and dam roll chock (for one side). For example, the steel strip width is 1800 mm and the internal dimension of the tank is 2000 mm. In this case, the allowable meandering amount is 100 mm. The allowable meandering amount varies depending on the maximum width of the steel strip passing through the line and the equipment specifications, but is generally about 100 mm to 300 mm. On the other hand, as shown in FIG. 8, the larger the skew angle θ, the smaller the amount of meandering that occurs. In order to suppress the generated meandering amount to 300 mm or less which is a general allowable value, the skew angle θ needs to be 0.6 ° or more. However, if the skew angle θ is too large, the force in the direction to make the sleeve perpendicular to the plate passing direction becomes strong, that is, the force that the roll is pressed against the tilt axis in the direction perpendicular to the plate passing direction becomes strong. As a result, it is difficult to rotate, causing problems of uneven wear and short life. Since the maximum meandering amount can be suppressed to a very small value of several tens mm or less at a skew angle of 3 °, the skew angle θ is preferably 0.6 ° or more and 3 ° or less.

S Steel strip 1 Pickling tank 2 Dam 2a Skid cap 3 Tank 4 Bridle roll 5 Ringer roll 6a, 6b Support roll 10 Steel strip support device 11 Support shaft 11A, 11B Shaft body 11a Shaft body 11b Rubber lining 11c Fluororesin coating 12, 13 Sleeve 12a, 13a Sleeve body 12b, 13b Acid resistant rubber 14, 15 Shaft support block 16, 17 Shaft support block receiver 18 Bearing block 18a Body 18b Rubber lining 18c Fluororesin film 19 Side wall of tank

Claims (7)

A steel strip support device in a pickling tank for supporting a steel strip that is continuously fed into a pickling tank in which at least two pickling tanks are formed by partitioning the inside by a dam so as not to contact the dam. There,
An acid-resistant support shaft that is bent in the direction opposite to the traveling direction of the steel strip near the center of the width, and an acid-resistant cylindrical sleeve that is rotatably provided around the left and right support shafts of the bent portion. A steel strip support device for a pickling tank, comprising:   The support shaft is composed of a bearing block in the center of the width, and a pair of left and right shaft centers that are bent in opposite directions to the traveling direction of the steel strip on both sides of the bearing block. The steel strip support device for a pickling tank according to claim 1.   The steel band support device for a pickling tank according to claim 1 or 2, wherein the skew angle of the bent support shaft is 0.6 ° or more and 3 ° or less.   The support shaft has a structure in which the surface of the iron material is coated with an acid-resistant material, and the surface thereof is further coated with a lubricious material. The steel strip support device for a pickling tank according to any one of claims 1 to 3, wherein the steel strip support device is provided.   The acid according to any one of claims 1 to 4, wherein a step portion having a diameter larger than a central portion in the longitudinal direction is provided on both end sides in the longitudinal direction of the inner circumference of the sleeve. Steel strip support device for washing tank.   The surface of the shaft support block provided at the end of the support shaft is perpendicular to the traveling direction of the steel strip, and the progress of the steel strip of the shaft support block receiver provided on the side wall of the pickling tank The steel strip support device for a pickling tank according to any one of claims 1 to 5, wherein a surface on the downstream side with respect to the direction is vertical.   7. The shaft support block according to claim 1, wherein the shaft support block has an inverted trapezoidal shape with a lower side as viewed from the side, and the shaft support block receiver has an inverted trapezoidal shape with an open top. Steel strip support device for pickling tanks.

Images