JP2608963B2 - Roller bearing structure in molten zinc bath - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION <Industrial application field> The present invention relates to a hot-dip galvanizing equipment, and more particularly, to a bearing structure of a roll provided in a hot-dip zinc bath.

<Prior Art> Conventionally, when hot dip galvanizing is continuously performed on a strip-shaped steel sheet, generally, as shown in FIGS. 4 and 5, the steel sheet 1 to be plated is once drawn into a hot-dip zinc bath 2. After that, the direction is changed by the sink roll 3, and further, the steel plate 1 is plated by the pair of stabilizer rolls 4 arranged opposite to each other.
While pulling up in the vertical direction while measuring vibrations and correcting warpage in the width direction, a surplus of molten zinc adhering to the surface of this is used as a pair of opposing wiping nozzles provided on the bath. 5 to blow down to a required plating film thickness.

In such equipment, the sink roll 3 or the stabilizer roll 4 rotates at a smooth constant peripheral speed so that relative slip does not occur between the body 3a or 4a and the steel plate 1 to be plated. Is an indeterminate condition, but contrary to this, often it does not rotate smoothly, slipping occurs with the steel plate 1 to be plated, and the quality of the plated surface is significantly impaired due to abrasion. .

In such a facility, the stabilizer roll 4 is rotatably supported by a cylindrical slide bearing 7 fitted on shafts 4b provided at both ends thereof and fixedly supported by hangers 6. The sliding surface between the sliding bearings 7 is lubricated by the molten zinc filled in the molten zinc bath 2.

As described above, since the cylindrical sliding bearing 7 depending on the lubricating action of the molten zinc is used, and a passive rotation linked to the movement of the steel sheet 1 to be plated is expected, the molten zinc bath 2 When a large amount of foreign matter enters the sliding surface between the shaft 4b and the cylindrical sliding bearing 7, the stabilizer roll 4 becomes difficult to rotate.
And the body portion 4a of the stabilizer roll 4 slips, causing abrasion on the surface of the steel plate 1 to be plated, and in extreme cases, the stabilizer roll 4 cannot rotate and the operation becomes impossible. Even things can happen.

Conventionally, in order to reduce inconvenience caused by entry of foreign matter into the sliding surface, the gap between the shaft 4b and the cylindrical bearing 7 is initially set to a wide value of several mm, and this gap is In practice, it became larger due to wear during use, and in practice it was necessary to operate in a rattling state.

As described above, since the stabilizer roll 4 is supported by the cylindrical bearing 7 in the rattling state, the stabilizer roll 4 is in an unstable rotation state in which the contact state between the stabilizer roll 4 and the steel plate 1 to be plated is constantly changed. By vibrating the steel plate 1,
This is a cause of impairing plating uniformity or giving a pattern to a plated surface.

The same applies to the sink roll 3.

Until now, as a measure for enabling the stabilizer roll 4 to rotate lightly, it has been considered to replace the cylindrical sliding bearing 7 with a rolling bearing many times, but it is inferior in life and reliability and high in cost. Therefore, it has not been put to practical use (see Japanese Utility Model Application Laid-Open No. 61-142858).

The use of ceramics having excellent corrosion resistance to molten metal has also been proposed (see Japanese Utility Model Application Laid-Open No. 63-73349,
However, since it is very expensive and the structure of the bearing portion is of the conventional type, a fundamental solution cannot be obtained in terms of vibration suppression.

<Problems to be Solved by the Invention> The present invention has been made to solve the above-mentioned problems of the bearing portions such as the sink roll 3 and the stabilizer roll 4 provided in the molten zinc bath. It is.

<Means for Solving the Problems> The present invention provides a bearing structure for rotatably supporting a roll used in a hot-dip galvanizing line of a hot-dip galvanizing line, wherein a conical hole is formed at the center of the end face of the roll. Roll, and a conical sliding bearing fitted into the conical hole and having a conical pointed tip for rotatably supporting the roll, the conical shape provided on the roll end face The tapered angle of the hole and the tapered angle of the conically shaped tip of the conical sliding bearing are equal to each other within the range of 30 to 120 °.

<Operation> The bearing portion of the roll in the molten zinc bath of the present invention has a roll provided with a conical hole at the center of the end face of the roll, and a tip fitted into the conical hole and rotatably supporting the roll. A conical sliding bearing having a conical pointed shape, a tapered angle of a conical hole formed in the roll end face, and a tapered angle of a conically shaped tip of the conical sliding bearing. Is equal to each other in the range of 30 to 120 °,
Rolls provided in the molten zinc bath can be supported with little clearance regardless of the wear of the bearing,
In addition, even if a foreign matter enters the bearing portion, an abnormal situation does not occur, and the rotational friction force can be reduced.

<Example> An example of the present invention will be described with reference to the drawings.

FIG. 1 shows an embodiment in which the present invention is applied to a bearing portion of a stabilizer roll, and is a diagram viewed from a direction perpendicular to a plane including a shaft.

In this figure, 14 indicates a stabilizer roll,
This is composed of a body part 14a with which the steel sheet to be plated contacts, and bearing parts 14b provided at both ends of the body part 14a. Reference numeral 16 denotes a conical sliding bearing for supporting the stabilizer roll 14.

The bearing portion 14b of the stabilizer roll 14 is a conical hole formed at the center of the end face.

The tip 16a of the conical sliding bearing 16 has a conical pointed shape, and the taper angle of this portion is equal to the taper angle of the bearing 14b of the stabilizer roll 14.

This taper angle can be selected in the range of 30 ° to 120 °, but if this angle is too small, the conical plain bearing 16
Not only is the bending strength of the bearing reduced, but also the escape when foreign matter is caught is not performed well, and if this angle is too large, when the stabilizer roll 14 is loaded in the radial direction, the conical sliding bearing 16 In general, good results can be obtained at about 70 ° because a problem arises that the generation of a force in the escape direction becomes too large to stably support.

The bearing portion 14b and the conical sliding bearing 16 are made of a molten zinc-resistant metal material or a ceramic material in order to improve the service life.
A groove (not shown) corresponding to an oil groove is engraved on the sliding surface so that molten zinc can enter into the sliding surface to perform a lubricating operation well.

The conical sliding bearing 16 is supported by a structure 15 called a hanger so as to be at a predetermined position with respect to the ground,
This itself is fixed so as not to rotate. The hanger 15 moves in such a direction as to push and pull the conical plain bearing 16 with respect to the bearing portion 14b, that is, in the axial direction of the stabilizer roll 14, so that the position thereof can be adjusted. When it is received, it automatically retreats to a position where excessive force disappears.

FIG. 2 is a view showing an example of the structure of the hanger. The hanger 15 is supported by a pin 20 and can swing about the pin 20 by the driving force of an actuator 21 such as a cylinder. . Accordingly, the position of the conical plain bearing 16 can be adjusted by the movement of the actuator 21.

Generally, a minimum gap (for example, about 0.5 mm) required for molten zinc to enter between the bearing portion 14b and the conical sliding bearing 16 to provide a lubricating effect, or a degree of light contact with each other By setting the position of the hanger 15, the stabilizer roll 14 is rotatably supported in a state where there is no backlash in practical use.

When the bearing portion 14b or the conical sliding bearing 16 is worn out during operation and the gap between them is to be enlarged, the actuator 21 is operated in a direction in which the conical sliding bearing 16 approaches the bearing portion 14b, and the gap between the conical sliding bearing 16 and the conical sliding bearing 16 is increased. Is kept constant, and the stabilizer roll 14 is rotatably supported in a stable state.

Also, if foreign matter contained in the molten zinc enters between the bearing portion 14b and the conical sliding bearing 16 during operation, the conical sliding bearing 16 receives a force in a direction inevitably pushed out, As a result, the actuator 21 automatically operates in the retreating direction of the hanger 15 to prevent an abnormal state.

In this structure, since the amount of protrusion of the conical sliding bearing 16 is short, it is easy to increase the bending strength of the conical sliding bearing 16, and therefore, the diameter of the sliding surface can be reduced, and the rotational friction force of the stabilizer roll 14 is reduced. can do.

In the above description, the stabilizer roll 4 has been described. However, the same applies to the sink roll 3, and the above-mentioned common problem can be solved at once by the present invention.

FIG. 3 shows an example in which a conical sliding bearing 16 for supporting the sink roll 3 is supported by a bath wall of the molten zinc bath 2 and is directly moved by an actuator 21. In this case, although the seal between the conical sliding bearing 16 and the bath wall of the molten zinc bath 2 becomes complicated, there is an advantage that a stronger support can be provided because no hanger is required.

<Effect of the Invention> As described above, in the bearing having the structure according to the present invention, the roll disposed in the molten zinc bath can be pivotally supported with little clearance regardless of the wear of the bearing portion. The advantage is that, even if foreign matter enters the bearing portion, it does not fall into an abnormal situation and the rotational friction force can be reduced, so that a high-quality hot-dip galvanized steel sheet can be manufactured without scratches on the plated surface. The industrial value of the present invention is great.

[Brief description of the drawings]

FIG. 1 shows an embodiment in which the present invention is applied to a bearing portion of a stabilizer roll, and is a diagram viewed from a direction perpendicular to a plane including a shaft. FIG. 2 is a view showing an example of the structure of a hanger supporting the bearing portion of the present invention. FIG. 3 is a view showing one embodiment in which the present invention is applied to a bearing portion of a sink roll, as viewed from a direction perpendicular to a plane including a shaft. 4 and 5 are explanatory views of a conventional continuous hot-dip galvanizing equipment. 1 ... steel plate to be plated, 2 ... molten zinc bath, 3 ... sink roll, 3a ... trunk, 4 ... stabilizer roll, 4a ...
... body, 5 ... wiping nozzle, 6 ... hanger, 7 ...
... Sliding bearing, 14 ... Stabilizer roll, 14a ... Body, 14b ... Bearing part, 15 ... Hanger, 16 ... Conical sliding bearing, 20 ... Pin, 21 ... Actuator.

Claims (1)

(57) [Claims] A bearing structure for rotatably supporting a roll used in a hot-dip galvanizing line of a hot-dip galvanizing line, wherein a roll having a conical hole formed in the center of the end face of the roll; And a conical sliding bearing whose tip for supporting the rotation of the roll has a conical pointed shape, the taper angle of the conical hole provided on the end face of the roll, A bearing structure for a roll in a molten zinc bath, characterized in that the tapered angle of the conical point of the slide bearing is equal to each other within a range of 30 to 120 °.