JPS6044116A - Bearing for back-up roll of thick plate rolling mill - Google Patents

Abstract

PURPOSE:To obtain a titled device that reduces fluctuation of exit side plate thickness and prevents lowering of load resisting function at the time of low speed by fixing a pair of double ball-and-roller bearings from both end faces by bearing outer ring fixing members through guide rings and forming to specified bearing thickness. CONSTITUTION:In remodeling an oil film bearing of a thick plate rolling mill to a ball-and-roller bearing, a pair of double ball-and-roller bearings 5, 6 that support a roll neck part 2 are provided interposing a space seat 13 in a chock 3 without remodeling the chock 3 of a back-up roll 1. Bearing outer rings 7, 8 that hold the bearings 5, 6 are fixed in axial direction by annular outer ring fixing members 11, 12 through roller guide rings 15, 16 arranged on both outer end faces. Inner rings 9, 10 are fixed by inner ring fixing members 17, 18. Further, the thickness (t) of the above-mentioned bearings 5, 6 is formed to satisfy relation of 0.1<=t/d<=0.13 where (d) is he shaft diameter of the roll neck part 2.

Description

TECHNICAL FIELD OF THE INVENTION The present invention relates to a bearing device for a backup roll of a plate rolling mill.

Technical Background of the Invention A plate rolling mill uses reverse rolling conditions and rolls in a high load region (approximately 5,000 tons). In order to facilitate the control of the thickness of the rolled material, it is required to roll the material at a speed as low as possible (for example, i 2 rpm or less) and to control the rolling speed.

Conventional thick plate FE and rolling mill back-up roll bearing devices usually employ a moboil type oil film bearing as shown in FIG.

That is, this oil bearing is made by fitting a sleeve B whose inner diameter is a tapered surface into a tapered roll neck part A, applying a key C, and attaching a white metal fitted inside the sleeve B and chock D. This structure has an oil film formed between the shell E and the bearing surface made of a bearing material such as .

Problems with background technology However, conventional oil film bearings have the following problems.

■ It is vulnerable to low-speed rolling in high-load ranges, and in reality, when the rotation speed of the backup roll is less than 12 rpm, it becomes difficult to form an oil film on the bearings, resulting in an extremely low load-bearing performance. It cannot withstand rolling and may cause oil film seizure.

■ The rotation accuracy of the bearing affects the accuracy of rolled products, but with oil film bearings, the oil film thickness changes as the rolling speed changes.
Variation occurs in the thickness of the exit side plate.

In order to prevent this, in recent years, hydraulic reduction devices have been adopted to correct the oil film thickness from the viewpoint of rolling control technology and to suppress oil film fluctuations. However, even with this method, it is not practical to control the rolling load in response to changes in the oil film when the roll rotational speed is accelerated or decelerated. In particular, during automatic plate thickness control, changes in the oil film act as a disturbance element, and the plate thickness variation on the exit side is particularly large, causing problems.

■ Oil film bearings cause eccentricity during roll rotation, but
If the rolls are eccentric, the roll grip will change during rolling, and the thickness of the sheet on the exit side will fluctuate.

Furthermore, during automatic plate thickness control, the eccentricity affects the plate as a large disturbance element, so that the variation in the plate thickness on the exit side becomes even larger.

Despite the above problems, oil film bearings are normally used as backup roll bearings in thick plate rolling mills, so oil film seizure is prevented during low speed rolling where the roll rotation is 1 or 2 rpm or less. Even if we try, there are limits to this, and the current situation is that oil film seizure cannot be avoided.

Furthermore, as a bearing device for a backup roll of a rolling mill, a device using a double-row cylindrical roller bearing instead of an oil film bearing is known from Japanese Patent Publication No. 56-38804; Since a standard-sized double-row cylindrical roller bearing is used in the radial direction, the mounting space for the oil film bearing, which has a small radial thickness, cannot accommodate a thicker cylindrical roller bearing. The installation space for the cylindrical roller bearing had to be expanded by machining. As a result, the wall thickness of the chock becomes thinner, so if this conventional structure is used in a plate rolling mill that attempts to roll under the aforementioned high load and at a very low speed, the chock may lack rigidity and deform. This is likely to occur, resulting in a problem of worsening the accuracy of the exit side plate thickness.

For these reasons, the conventional drawing cannot be applied to plate rolling mills.

Purpose of the Invention The present invention has been made in view of the above circumstances, and its purpose is to improve the oil film bearing without reworking the inner diameter of the chock when modifying the oil film bearing device of a thick plate rolling mill into a rolling bearing device. The purpose of the present invention is to provide a device that can use the mounting space for a chock as it is. The backup roll for plate rolling mills also reduces variations in the exit side thickness of rolled material, prevents deterioration in load-bearing performance during low-speed rolling, and prevents changes in oil film thickness and roll eccentricity when accelerating and decelerating rolling speeds. The purpose of this invention is to provide a bearing device for.

Summary of the Invention The present invention maintains the inner diameter of the chock without reworking, supports the roll neck portion of the backup roll within the chock with a pair of double-row rolling bearings, and fixes each outer ring of the bearing in the axial direction. A sealing portion is formed between the outer ring fixing members provided at both ends of the chock and the end of each inner ring outer circumferential surface on the outside of the bearing.

Embodiment of the Invention FIG. 2 is a longitudinal cross-sectional view of an embodiment of the invention, in which l is a back-up roll of a thick plate rolling mill, and the roll neck portion 2 is a large diameter shaft portion 2a, a medium diameter Shaft portion 2b.

The small diameter shaft portion 20 at the tip and the conical root portion consist of a portion 2d. In the inner hole 4 of the chock 3, a pair of double-row cylindrical roller bearings 5 and 6 are fitted in parallel with a spacer 13 sandwiched between the outer rings 7 and 8. One annular outer ring fixing member 11 is fixed by a front cover 51 which will be described later and is bolted to the side, and the other annular outer ring fixing member 12 is fixed to the other end of the chock 3 by a bolt 39 or the like. The outer rings 7, 8 are connected to each other through roller guide rings 15, 16 arranged at both outer ends of the outer rings 7, 8 of the bearings 5, 6.
is fixed in the axial direction. Here, one of the outer ring fixing members 11 may be formed by a shoulder portion provided integrally with the chock 3. Reference numeral 14 denotes a cylindrical ring that is fitted and fixed to the medium diameter shaft portion 2b of the roll neck portion 2 with a tight fit, and its outer diameter is designed to be the same as the diameter of the large diameter portion 2a.

The inner rings 9 and 10 of the pair of bearings 5 and 6 are loosely fitted to the large diameter shaft portion 2a of the roll neck portion 2 and the cylindrical ring 14, and are press-fitted and fixed to the conical rooting portion 2d of the roll neck portion 2. an inner ring positioning fillet ring 17,
It is positioned by a thrust ring 18 for positioning the inner ring, which is loosely fitted to the small diameter shaft mzc of the four-wheel neck portion 2. Inner and outer circumferential surfaces 9a are provided on the mutually abutting end surfaces of the inner E*9*1o.

9b, 10a, radial passage 19°2 communicating with IQb
0 is provided, and the end faces of each inner ring 9 and 10, which are positioned by the fillet ring 17 and the thrust ring 18, are provided with axial notches 21 and 22 at several positions in the circumferential direction, respectively.
is provided, and the inner ring 9,100 is formed by the notch 21°22.
Inner and outer peripheral surfaces 9a, 9b.

10a and 10b are connected to each other. One end surface 18a of the thrust ring 18 is in close contact with an end surface 25 of the medium diameter shaft portion 2b of the roll neck portion 1, and a knock pin 26 implanted in the end surface 25 is inserted into the one end surface 18a of the thrust ring 18.
The thrust ring 18 is prevented from rotating by engaging with a radial notch groove 27 formed in the thrust ring 8a.

The wall thickness t of the bearings 5 and 6 is made thinner than the large shaft diameter d of the roll neck portion 2 so that 0.1≦t/d≦0.13. The biggest advantage of reducing the wall thickness t of the bearings 5 and 6 is that when converting an oil film bearing in a conventional thick plate rolling machine to a rolling bearing, no machining of the inner diameter of the chock 3 is required at all. , the first part of the roll neck part 2
By simply modifying the tapered surface T shown in the figure to a cylindrical surface, the mounting space for the oil film bearing on the chock 3 can be used as is, and the wall thickness of the chock 3 before modification can be maintained.

Incidentally, in conventional oil film bearings, the ratio of the average wall thickness of the bearing to the average shaft diameter of the roll neck portion is usually 0.1 to 0.13.

In addition, each double row cylindrical roller 1 extraction 5.6 is connected to the inner and outer rings 9,
10, 7.8, cage 28, 29 and cylindrical roller 3
0.31, and the cylindrical roller 30°31 is Rakugai@7.
It is a well-known practice that the transfer is guided by fixing nails 32, 33, spacers 13 and roller guide rings 15, 16 formed integrally with 8. Furthermore, supply channels 34.35 provided at several locations around the circumference of the fixing nails 32.33 of the outer ring 7.8
lubricant is supplied to the inside of the bearing from the supply path (not shown) of the chock 3 through the exhaust path 36 provided at several locations around the circumference of the spacer 13 and the exhaust formed in each outer ring fixing member 11, 12 and the chock 3. The lubricant can also be discharged from passages 37 and 38.
As is well known. Seal retaining rings 23 and 24 are fitted and fixed to step portions 9c and 10o provided on both sides of the outer peripheral surfaces 9a and 10a of the inner rings 9 and 10, respectively. The seal retaining rings 23, 24 respectively have the steps 9c,
A lip 23a is fitted and fixed to the outer ring fixing member 10a, and the lip 23a is in sliding contact with the inner surfaces 11a and 12'a of the outer ring fixing member 11°12 on its outer periphery.
.

Rubber rings 23 b, 24 b with a V-shaped cross section having 24 a
are attached to serve as sealing means for both ends of the pair of double-row cylindrical roller bearings 5 and 6.

The conical root of the roll neck part 2 is part 2dKFE.

In the IJ ring 17, the conical root has an inner diameter tapered surface 40 along the portion 2d, and has an upper annular cavity 41 and a lower annular cavity 42 on the outer circumferential side. A cylindrical portion 12b extending in the axial direction on the opposite side of the cylindrical portion 12c that contacts the roller guide ring 16 of the outer ring fixing member 12 is inserted into the annular space 41 at the bottom and is loosely fitted. do. Then, the cylindrical portion 12c
An oil sear A/43 is interposed between the inner and outer peripheral surfaces of the fillet ring 17 and the fillet ring 17 to seal the radial gap between the two members 12b and 17, and a bolt is inserted between the outer peripheral surface 17a of the fillet ring 17 and the end surface of the chock 3. A slight gap c is formed between the scale cover 45 and the scale cover 45 fixed with 44 or the like. Also, a step portion 171 formed on the outer surface of the fillet ring 17
), and its seal lip is attached to the inner circumferential surface of the axially protruding portion 1b formed on the barrel end surface 1a of the roll l and whose end surface abuts the side surface 17c of the same step portion 17b of the fillet ring 17. The fillet ring 17 and the roll neck part 2 are completely sealed by sliding contact.

Furthermore, scale, water, etc. that have entered the lower part of the scale cover 45 through the slight gap C□ between the scale cover 45 and the fillet ring 17 are allowed to pass through the upper annular cavity 42 of the fillet ring 17 to the outside of the bearing. A drain hole (not shown) is provided for draining.

Inner ring 10 fitted to large diameter shaft portion 2a of roll neck portion 2
The inner rings 9 and 10, the thrust ring 18, and the fillet ring 17 are provided with the inner rings 9 and 10, the thrust ring 18, and the fillet ring 17 to prevent galling. Radial passages 19, 20, 21
．． A 47° 48 for holding and guiding a portion of the lubricant supplied through 22 is disposed around the periphery in a continuous spiral or u-ring shape. Of course, when provided in a spiral shape, the lubricant is formed in a direction such that the lubricant is transferred from the roll shaft end side to the roll large diameter shaft side.

A thrust roller bearing 49 for receiving the axial load of the roll 1 is provided on the small diameter shaft portion 2c at the tip of the roll neck portion 2. This thrust roller bearing 49 is located between a front cover 51 which also serves as a bearing box and which is fixed to the outer end of the chock 3 with bolts 50 and a thrust receiver 52 which is fixed inside the front cover 51. A screw ring 53 fixed to the
It is fixed between the thrust receiver 52 and an adjusting screw 54 that is screwed into the thrust receiver 52 .

Next, FIG. 3 shows a modified embodiment, in which the sealing means between the inner surfaces of the inner rings 9, 10 and the outer ring fixing parts i'll, 12 are the inner rings 9, 10.
Stepped portions 9 provided on both sides of the outer surfaces 9a and 10a of 10 Q
+ 10 c, one of the flingers 57 and 59 are fitted and fixed, respectively, and the other flinger 58 is held between the outer ring fixing member 11, 12 and the guide ring 15, 16.
', 60. To be more specific, the gap is located between one of the flingers 57, 5.
Slight gap Q between the outer surface of No. 9 and the inner No. 1 surface of outer ring fixing member 11.12, one of the 7 linkers 57°59
A slight gap C3 between the inner surface of the stepped portion 58.60 and the outer surface of the other flinger 55.56, the bottom surface of the stepped portions 581, 60 and the other flinger 55.56. A slight gap C4 is continuously formed between the inner circumferential surface of each of the two parts.

In the embodiment shown in FIG. 3, the end surfaces of the inner rings 9.degree.
4i & 9. The inner and outer circumferential surfaces 9a, 9b, 10a, 10b of the inner rings 9, 10 are respectively attached to the end surfaces that contact the end surfaces of the xo.
Radial passages 19, 20, 61, 62 communicating with
, 63, and 64 are provided.The other parts are as follows.
Since it is the same as the embodiment shown in the figure, the explanation will be omitted.

In each embodiment, the roll neck portion 2 is formed with a stepped shaft portion having a large diameter shaft portion za and a medium diameter shaft portion 2b, and a cylindrical ring 14 is fitted onto the medium diameter shaft portion 2b. omitted,
The medium-diameter shaft portion 2b and the large-diameter shaft portion 28 may have the same diameter.Of course, in this case, lubricant retaining and guiding grooves 47 and 48 are formed on the inner peripheral surfaces 9b and 10b of both inner rings 9 and 1°. . Furthermore, although a pair of double-row cylindrical roller bearings 5.6 are used in each embodiment, a pair of tapered roller bearings may also be used.

Effects of the Invention The present invention can be fully understood from the embodiments described above, and has the following effects compared to conventional bearing devices.

■ Set l3JJlt of the roller bearing to be 0.1≦-≦0.13 with respect to the roll neck diameter.
By making the wall thinner, the mounting space for the oil film bearing on the chock in a conventional thick plate rolling mill can be used as is. Therefore, when modifying a conventional thick plate rolling mill, there is no need to process the inner diameter of one chock, the thickness or rigidity of the chock before modification can be maintained, and the accuracy of the exit plate thickness is not affected.

■ As shown in Fig. 4, when low-speed rolling is performed at a backup roll rotation speed of 12 rpm or less, conventional oil film bearings have extremely low load resistance, but the bearing device of the present invention has is about s,oo.

II at low speed and high load range
It can withstand sufficient E-rolling without causing seizure.

■ Even if the roll rotation speed is accelerated or decelerated during automatic plate thickness control, since the bearing device of the present invention is a roller 75 bearing, there is almost no oil film fluctuation unlike in conventional oil film bearings, and therefore the fifth As shown in the figure, when the roll rotation speed is changed,
Traditional? The bearing device of the present invention has smaller load fluctuations than the FJJ membrane bearing. Further, as shown in FIG. 6, the amount of roll eccentricity during roll rotation is smaller in the bearing device of the present invention than in the conventional oil film bearing.

In view of the above, in the present invention, the variation in the outlet side plate thickness of the rolled material is much smaller than in the conventional oil film bearing, and the material yield is also improved by about 0.3%.

■ Each outside @ fixing member and each inner ring outside Ill! 'Since a small gap formed by a combination of flingers or a sealing means is provided between the bearing and the I surface, the lubricant supplied to the inside of the bearing is collected in the lower half of the bearing and becomes an oil bath. This structure improves the lubrication effect of the bearing during low-speed rolling.

In the case of the structure of the other person's embodiment, there are also the following additional effects.

■ In the case of the structure of the example, the lubricant holding and guiding surface is formed on the inner circumferential surface of one inner ring, and the lubricant is formed on the outer circumferential surface of the cylindrical ring, so it is formed on the inner circumferential surface of both inner rings. It is easier to process than .

[Brief explanation of the drawing]

FIG. 1 is a vertical cross-sectional view showing the main parts of a conventional device (FIG. 2 is a vertical cross-sectional view showing the main parts of an embodiment of the present invention, and FIG. 3 is a longitudinal cross-sectional view of the main parts showing a modified embodiment. Fig. 4. Fig. 5 and Fig. 6 are graphs comparing the effects of the conventional device and the present invention, respectively. 1...Roll, double-rotated roll neck g, 2a...Large diameter shaft portion, 2b...Medium diameter shaft part, 3...Chock, 4...
・Inner hole, 5.6...Double row rolling bearing, 7,8...
Outer ring, 9゜10...Inner ring, 11.12...Outer ring fixing member, 15゜16...Roller guide ring, 17...Inner ring fixing member (fillet ring), 18...Inner ring fixing member ( Thrust Ring) Applicant Sumitomo Metal Industries Co., Ltd. Koyo Seiko Co., Ltd. Agent Gopo-Keiji Procedural Amendment (Method) 1. Display of the case 1982 Patent Application No. 1534.54 2 Name of the invention Bearing device for backup rolls of plate rolling mill 3 Person making the amendment Relationship to the case Applicant name Title (211) Sumitomo Metal Industries, Ltd. (1 other person) 4. Agent November 29, 1988 6. Subject of amendment 7. Contents of amendment (1) On page 21, line 9 of the specification, after “as shown”, “
The roll eccentricity measurement results measured with Kiss Roll 1000) are corrected as follows. (2) On page 21, line 10 of the same book, after "of the present invention," amend "Korogashi." (3) Correct figures 4, 5, and 6 as shown in the attached sheet. Applicant: Ninyu Metal Industry Co., Ltd., Koyo Sekiko Co., Ltd., -Zo Agent: Goho - Keibo...Paper Procedural Amendment 1. Display of the case 1982 Patent Application No. J53454 2 Name of the invention Bearing device for buffer/sibro roll of thick plate rolling mill 3 Person making the amendment Relationship to the case Applicant name Title (21,1) Sumitomo Metal Industries, Ltd. Company (1 other person) 46 Representative specification (claims column, detailed description of invention column)
8. Contents of amendment (1) The scope of patent claims will be amended as shown in the attached sheet. (2) The following explanation will be added between lines 9 and 10 on page 8 of the specification. ``The first invention maintains the inner diameter of the chock without reworking, supports the roll neck portion of the backup roll within the chock with a pair of double-row rolling bearings, and
The bearing is designed to satisfy the relationship 0.1≦t/d≦0.13, where t10 is the wall thickness of the bearing and d is the shaft diameter of the neck portion. J (3) On page 8, line 10 of the same book, the phrase ``one book'' was replaced with ``also the second book''.
Correct it with "No." Japanese Patent Application No. 58-153454 (Amendment 2) claims the invention, which is provided at both ends of the chock for fixing the outer ring in the axial direction through a pair of double-row roller guide rings supporting the roll neck portion. The outer ring fixing member is configured to satisfy the relationship of an annular ring fixed member disposed on the outer end surface of the pair of bearing inner rings and fixing the inner ring in the axial direction. a pair of double-row rolling bearings that are fitted in parallel and support the roll neck portion;
An outer ring fixing member provided at both ends of the chock that fixes the outer ring in the axial direction via a roller guide ring arranged on the out-of-plane end surfaces of the pair of bearing outer rings; A thick plate comprising an annular inner ring fixing member which is arranged to fix the inner ring in the axial direction, and a sealing means is provided between the end of each inner ring outer peripheral surface on the outside of the bearing and the outer ring fixing member. Bearing device for a backup roll of a rolling mill (3) The sealing means is formed into a seal ring that is fitted and fixed to an end portion of the outer peripheral surface of the inner ring on the outside of the bearing, and whose lip slides into contact with the inner surface of the outer ring fixing member. Claims (2)
(4) The sealing means includes a flinger that is fitted and fixed to an end of the outer peripheral surface of the inner ring on the outside of the bearing, and an inner surface of the outer ring fixing member. A bearing device envelope for a backup roll of a thick plate rolling mill according to claim (2), comprising a slight gap formed between the flinger and the flinger. A patented backup roll bearing device in which a ring is fitted onto the middle diameter shaft of the roll neck, and one double row roller supports the inner ring of the bearing.

Claims (1)

[Claims] (1) A chock and a p
- A pair of double-row rollers that support the runnet portion are provided at both ends of the chock that fixes the outer ring in the axial direction via a shaft bearing and roller guide rings arranged on both outer end surfaces of the pair of outer rings of the bearing. an annular inner ring fixing member disposed on both outer end surfaces of the pair of inner rings of the bearing and fixing the inner rings in the axial direction; Bearing device for a backup roll of a thick plate rolling mill characterized by providing a sealing means between the fixing member .1≦t/d≦0.13 The bearing device (3) for a backup roll of a plate rolling mill according to claim (1), wherein the sealing means is , the thick plate rolling according to claim (1), wherein the inner ring outer 1 is fitted and fixed to the end of the surface on the outside of the bearing, and the lip is formed as a seal ring that slides into contact with the inner surface of the outer ring fixing member. Bearing device for backup rolls (4) The sealing means includes a flinger that is fitted and fixed to the end of the outer circumferential surface of the inner ring on the outside of the bearing, and a 7" linker that is attached to the inner surface of the outer ring fixing member. A bearing device (5) for a back-up roll of a plate rolling mill according to claim (1), comprising a cylindrical ring with a lubricant retaining and guiding groove provided on the outer periphery. A bearing device for a back-up roll of a plate rolling mill according to claim (1), wherein one of the double-row rollers is fitted into the middle-diameter shaft portion of the roll neck portion and supports an inner ring of the bearing.