JPH0630153U - Bearing support device for dipping rolls in hot dip bath - Google Patents

Abstract

(57) [Summary] [Purpose] To enable long-term stable use and repeated use of roll bearings in a hot dip bath. [Structure] A bearing supporting device for a roll immersed in a hot dip bath comprises a support arm (6) extending a roll (3, 4) immersed in a hot dip bath (5) into the hot dip bath (5). It is rotatably supported by a rolling bearing (7a) held in a bearing box (11) attached to the tip.
This device has a width of 0.5 mm in the radial direction of the bearing box (11).
The above slits (110) are provided, and the remaining portion (11) of the bearing box (11) except for the arc portion (θ) of 120 degrees on the load side.
The thickness of 1) is formed to 5 to 20 mm. Rolling bearing (7
The aligning ring (12) of a) is made of metal, and the aligning ring (12) is
It is also possible to provide a slit (120) of 0.5 mm or more in the radial direction.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to a device for supporting a roll immersed in a hot dip bath, and more particularly, to an improvement of a bearing support device for rotatably supporting the roll.

[0002]

[Prior art]

 When forming a plating layer of another metal on the surface of a steel strip, in addition to plating by electrochemical treatment, treatment by a so-called hot dipping bath in which a metal is melted and immersed in a plating bath is widely used. For example, when the surface of a steel strip is plated with zinc using such a hot dip bath, there is an apparatus disclosed in Japanese Utility Model Laid-Open No. 61-90852. In this apparatus, as shown in FIGS. 3 and 4, the steel strip 2 guided into the plating tank 1 changes its direction by a sink roll 3 and leaves the plating tank 1 via a support roll 4. The sink roll 3 and the support roll 4 for guiding the steel strip 2 in the state of being immersed in the hot molten zinc bath 5 are respectively provided with rolling bearings 7 at the tips of the support arms 6 as shown in FIG. It is rotatably supported via. Since the rolling bearing 7 is required to have heat resistance and wear resistance, it is preferably made of ceramic. However, the ceramic bearing 7 is significantly affected by its usage. The support arm 6 of the bearing 7 and the sink roll 3 are generally made of metal, which causes a difference in thermal expansion from the bearing 7, causing various problems.

For example, the support arm 6 of the bearing 7 undergoes thermal deformation in the high-temperature zinc bath 5, and the roll also thermally expands to maintain the positional relationship between the support arm 6 and the bearing 7 in a normal state. Is extremely difficult. Therefore, an unexpected load is applied to the bearing 7, and the bearing 7 is often damaged. Further, the support arm 6 and the sink roll 3 are cooled when they are pulled out of the zinc bath 5 for replacement after being used for a certain period of time. At this time, since the support arm 6 and the sink roll 3 are made of metal, the contraction amount is larger than that of the ceramic bearing 7. Zinc remains in the resulting gap and solidifies to compress and damage the bearing during cooling and contraction.

Further, since the bearing box fixed to the support arm is usually made of metal, the galvanized metal enters the gap due to the difference in thermal expansion between the ceramic bearing and the bearing box, as described above. The metal remains, and the bearing housing presses the bearing, resulting in damage.

[0005]

[Problems to be solved by the device]

 The present invention is to obtain a bearing support device for a hot dipping bath dipping roll that can be stably used for a long period of time and can be repeatedly used.

[0006]

[Means for Solving the Problems]

 A bearing support device for a roll immersed in a hot dip bath according to the present invention is a rolling bearing held in a bearing box in which a roll immersed in a hot dip bath is mounted at the tip of a support arm extending into the hot bath. Rotatably supported by. In this bearing support device, a slit having a width of 0.5 mm or more is provided in the radial direction of the bearing box, and the thickness of the remaining part of the bearing box excluding the arc portion of 120 degrees on the load side is formed to be 5 to 20 mm. .

The centering ring of the rolling bearing may be made of metal, and a slit of 0.5 mm or more may be provided in the radial direction of the centering ring.

[0008]

[Action]

 In the bearing support device of the present invention, a slit having a width of 0.5 mm or more is formed in the bearing box and, if necessary, the aligning ring in the radial direction.

The reason for setting the lower limit of the slit width to 0.5 mm is that when the bearing supporting device is pulled up from the hot dip plating bath (for example, a zinc plating bath), the slits of the bearing box and the centering shaft are opposite to each other. If zinc remains in the form of a bridge, the zinc solidifies and contracts, pulling the opposite surface of the bridge, and applying excessive compressive stress to the outer ring of the bearing, causing damage to the bearing. This is because molten zinc easily falls from the slit. Therefore, the bridge phenomenon cannot be completely prevented unless the slit width is set to 0.5 mm or more. Also, the upper limit of the slit width is that the bearing should not come off from the bearing box and the aligning ring when handling the bearing support device, and that the bearing should be placed in the bearing box and alignment center in the bearing support device when an axial load is applied. The axial load and the thickness of the bearing housing are taken into consideration in order to maintain the position of the wheel so that it will not be displaced. The angle formed with the center of the support roll is preferably 120 degrees or less.

In addition, the thickness of the bearing housing is stored in the bearing housing so that the thickness of the remaining portion in the radial direction excluding the arc portion of 120 degrees on the load side is not separated from the bearing housing. It is set to 5 to 20 mm so as not to apply excessive stress. Even within the range of 120 degrees on the load side, the bearing box or aligning ring is notched, so excessive compressive stress is not applied to the outer ring of the bearing, so the bearing will not be damaged due to contraction of the bearing box. A thickness of 5 to 20 mm is required to obtain the strength of the remaining portion.

In the present invention, the bearing is made of a ceramic material. Ceramic materials are suitable for dipping in a hot dip plating bath because they have low thermal deformation and excellent heat resistance and wear resistance.

[0012]

【Example】

 An embodiment of a device for supporting a dipping roll in a hot dip bath according to the present invention will be described with reference to FIGS.

As shown in FIG. 3, the steel strip 2 introduced from the continuous furnace 10 enters the hot dip plating bath 5 through the snout 8, is diverted upward by the sink roll 3, and is warped by the support roll 4. After straightening and stabilizing the strips, they come out on the bath surface and are controlled by the nozzle 9 to a predetermined amount of plating adhesion.

The present invention is applied to a support roll 4 and / or a sink roll 3 immersed in a hot dip bath 5.

As shown in FIGS. 1 and 2, a supporting device is a bearing in which a synchro 3 or a support roll 4 immersed in a hot dip plating bath 5 is attached to the tip of a support arm 6 extending into the hot dip bath 5. It is rotatably supported by a rolling bearing 7a held in the box 11.

An example in which the present invention is applied to the support roll 4 will be described below. In the supporting device of the present invention, the bearing 7a has an outer ring 71, balls 72, and an inner ring 73 all made of ceramic, and the balls 72 are of a ball bearing type using a cage 74. The aligning ring 12 is arranged between the bearing box 11 and the outer ring 71 so that the outer ring 71 can be easily aligned with the bearing box 11. The bearing box 11 is attached to the support arm 6 through the pedestal 13.

The retainer 74 in the bearing 7 a separates the balls 72, prevents the balls 72 from contacting each other, and prevents friction and wear of the balls 72.

In the bearing support device of the present invention, as shown in FIG. 1, a slit 110 having a width of 0.5 mm or more is cut out in the radial direction of the bearing box 11, and the load box side 120 of the bearing box 11 is provided. The thickness in the radial direction of the bearing box 11 of the remaining portion 111 excluding the arc portion θ of the degree is molded to 5 to 20 mm.

Here, the arc portion θ on the load zone side means a range of about 120 degrees from the position 16 rotated by θ ′ = about 30 degrees clockwise from the vertical line 15.

The aligning ring 12 of the rolling bearing 7a may be made of metal, and the slit 120 of 0.5 mm or more may be provided in the radial direction of the aligning ring 12.

The slits 110, 120 of the bearing box 11 or the aligning ring 12 are preferably provided on the non-load zone side.

The ball bearing molded as described above was applied to a model device similar to the device shown in 1 for an experiment. The shaft diameter (= inner ring inner diameter) = 80 mm, the bearing outer diameter = 200 mm, was run for 20 days under the conditions of average steel strip speed = 120 mm / min, average steel strip size = 0.8 mm thickness x 1000 mm width. After the operation, the model device was reused after being once pulled out from the hot dip plating bath. As a result, it was possible to drive for another 20 days.

As described above, it was confirmed from the above experimental results that it can withstand a long-term operation as compared with the conventional one.

[0024]

[Effect of device]

 According to the present invention, the original function of the ceramic bearing can be exerted, and the bearing can be stably and repeatedly used for a long time without damage.

[Brief description of drawings]

FIG. 1 is a side view of a bearing support device of the present invention.

FIG. 2 is a cross-sectional view taken along the line II-II of FIG.

FIG. 3 is a schematic explanatory diagram of a conventional hot dip bath facility.

FIG. 4 is a partial cross-sectional view taken along the line IV-IV in FIG.

[Explanation of symbols]

1: hot dip bath, 2: steel strip, 3: sink roll, 4: support roll, 6: support arm,
7, 7a: Bearing, 11: Bearing box, 12:
Aligning wheel, 13: pedestal, 71: outer ring, 73:
Inner ring, 74: cage, 110, 120: slit.

Front Page Continuation (72) Creator Akio Aoki 511-4-103 Chigasaki, Chigasaki City, Kanagawa Prefecture (72) Kunio Hayashi 5-29-2 Shonandai, Fujisawa City, Kanagawa Prefecture

Claims (2)

[Scope of utility model registration request] 1. A hot dipping bath which rotatably supports a roll placed by dipping in a hot dipping bath, which is rotatably supported by a rolling bearing held in a bearing box mounted at the tip of a support arm extending into the hot dipping bath. In the bearing support device for rolls, a slit having a width of 0.5 mm or more is provided in the radial direction of the bearing box, and the thickness of the remaining part of the bearing box except the arc portion of 120 degrees on the load side is set to 5 to 20 mm. A bearing support device for a dipping roll in a hot dip bath. 2. The bearing support device according to claim 1, wherein the aligning ring of the rolling bearing is made of metal, and a slit of 0.5 mm or more is provided in the radial direction of the aligning ring.