GB2240608A

GB2240608A - Steel mill roll

Info

Publication number: GB2240608A
Application number: GB9002554A
Authority: GB
Inventors: Axel Hendricks; Brian Edward Earthrowl
Original assignee: Cooper Roller Bearings Co Ltd
Current assignee: Cooper Roller Bearings Co Ltd
Priority date: 1990-02-06
Filing date: 1990-02-06
Publication date: 1991-08-07
Also published as: GB9002554D0

Abstract

A roll for use in rolling steel strip from a continuous casting machine is composed of cylindrical sections (4, 5) each having a shaft (6, 7) extending therethrough. The shafts (6, 7) are supported at their ends with bearings (1, 2). At the centre of the roll there is a journal member (8) welded to the cylindrical sections (4, 5). The journal member (8) has a recess (8a) with a surface directly forming the inner race of a rolling element bearing assembly (10, 11, 12, 13). <IMAGE>

Description

STEEL MILL ROLL This invention relates to a steel mill roll, for example, for use in a continuous casting machine.

A continuous casting machine uses a large number of rolls to guide and support the steel product. Typically, these rolls are supported by two end bearings and a centre bearing. The centre bearing is usually of split construction. Such a bearing has its raceways and housings made in halves so that they can be assembled on to a necked or recessed shaft or journal forming the link between two adjacent portions of the roll. The journal may be solid or separately manufactured and welded to the cylinders which form the main portion of the roll.

In a continuous casting machine, space is at a premium, particularly at the centre of the roll, and it is therefore necessary to design the bearings so that they are run at the limits of their capacity. This applies particularly to the centre bearing. In consequence, it is sometimes necessary to renew the bearing during the life of the roll. This increases running costs for the continuous casting machine, both by increasing direct maintenance costs and by decreasing the amount of time the machine is available to cast steel.

According to the invention, there is provided a steel mill roll, having at least one bearing the roll being provided with a shaft or journal for the or each bearing, the surface of the journal forming directly the inner race of the bearing.

The bearing is any anti-friction bearing, such as a roller bearing. The bearing with the inner race formed by the journal may be intermediate the ends of the roll.

Significantly increased bearing capacity can be achieved by integrating the inner race of the bearing with the journal since this creates more space usable to accommodate larger and/or extra rolling elements. The journal may be a separately-formed member which connects two adjacent portions of the roll and is preferably a rolled steel component whose surface has been machined and heat treated to form the inner race of the bearing.

Because of the enhanced capacity it is envisaged that a roll in accordance with the invention will not require the replacement of the bearing during the life of the roll, thereby achieving substantial savings in maintenance costs.

The invention may be understood more readily and various other aspects and features of the invention may become apparent from consideration of the following description.

An embodiment of the invention will now be described by way of example only with reference to the accompanying drawings, wherein: Figure 1 is a side elevation of a roll for a continuous steel casting machine, of the type with which the invention is concerned; Figure 2 is a sectional view of a portion of a typical roll in accordance with existing designs; and Figure 3 is a view corresponding to that of Figure 2, but showing a roll in accordance with the present invention.

The roll illustrated in Figure 1 is mounted with end bearings 1 and 2, and a centrally-placed split cylindrical roller bearing 3. As shown in Figure 2, the roll, in one example, consists of generally cylindrical sections 4 and 5, with a tubular shaft 6 and 7 respectively through each. A journal member 8, consisting of a unitary component is welded into the ends of the cylindrical sections 4 and 5 to join them together. The member 8 has internal passages for water cooling purposes but this is purely exemplary.

In the conventional construction shown in Figure 2, the journal member 8 is provided with a circumferential recess 8a, around which is fitted the inner race 9 of the bearing, in the form of two semicircular components 9a and 9b. Lower 10 and upper 11 housing members assemble around the inner race 9. The lower housing 10 provides support for the roll. Seals 12 and 13 enclose the bearing at each side.

Figure 3 shows a construction in accordance with a preferred embodiment of the invention, in which the recess 8a in the journal 8 is not cut to the same depth as that in the conventional construction illustrated in Figure 2. Instead, the surface of the recess is machined to provide a profile corresponding to the surface of the inner race 9 of the bearing, the other components of the bearing then being fitted over the race 9 in similar manner to the conventional construction. The conventional split in the race is not necessary. The surface of the journal may be heat - or otherwise-treated to ensure that the race formed thereon is of suitable durability. The modified design creates more space for the bearing which means that additional rollersand/or larger rollers can be used. This in turn increases bearing life.

The centre bearing is not necessary a roller bearing and in other designs other types of bearings can be employed. In the modified design the centre roller bearing 3 is partly formed by the journal while the end bearings 1,2 which may be solid bearings are unchanged.

It is, however, possible to modify one or both end bearings alternatively or additionally in a similar fashion.

Claims

1. A steel mill roll, having at least one bearing, the roll being provided with a journal for the or each bearing, the surface of the journal forming directly the inner race of the bearing.

2. A roll according to claim 1, wherein the bearing is a roller bearing.

3. A roll according to claim 2, wherein the bearing is a cylindrical roller bearing.

4. A roll according to claim 1, 2 or 3 wherein the bearing is intermediate the ends of the roll.

5. A roll according to any one of claims 1 to 4, wherein the journal is a separately-formed member connecting two adjacent portions of the roll.

6. A roll according to any one of claims 1 to 4, wherein the journal is an internal part of the roll.

7. A roll according to claim 5 or 6, wherein the journal is a component whose surface has been heat treated and machined to form the inner race of the bearing.

8. A steel mill roll, substantially as described with reference to Figures 1 and 3 of the drawings.