FI104343B - Sliding bearing for the roll to a paper / cardboard machine or finishing machine - Google Patents

Description

104343

Roller bearing for paper / board machine or finishing machine roller. - Glidlagring för valsen account en pappers- / cardboard eller efterbehandlingsmaskin.

The present invention relates to an outboard roller bearing around a roll axis of a paper / board machine or a finishing machine, comprising hydrostatic bearing elements around the shaft which are provided with sliding elements adapted to position the shaft of the roller to support the shaft; , as with the bearing bar.

The invention also relates to a method for cooling the slip-bearing deposition of a roll of a paper / board machine or a finishing machine, in particular a heated roll, around a roll axis, which slide bearings include hydrostatic bearings around the roll. rib elements provided with sliding elements • 20 arranged to position about the axis of the roll so as to rotatably support the roll relative to the frame member.

Such non-slip bearings on rollers, for example nip forming rollers, replace roller bearings and less favorable sliding bearing solutions. The above-described sliding bearing is achieved, for example, by the arrangement of patent application FI 970624, which is schematically shown in Figure 1. The prior art solution of Figure 1 30 comprises exterior roll hydrostatic bearing elements 3 mounted on a bearing bracket 5 and freely positioned to form a nip about axis 2 of roll 1. Said nip is formed with the counter roll 12.

35

Particularly in heated rollers (thermal rollers) where the heat transfer from the roll shaft to the bearing elements is particularly strong, such heat transfer 2 104343 may result in damage to the sliding bearings or other hydraulic components.

It is an object of the invention to provide an improved roller bearing outside the roll of a paper / board machine or a finishing machine which interrupts or at least substantially reduces the thermal energy flow from the roller to the slide elements and avoids excessive heating of the slide elements and consequent problems. A further object of the Kek-10 invention is also to minimize the temperature difference between the sliding surfaces.

To achieve these objects of the invention, the non-roller bearings of the paper / board machine or the finishing machine 15 according to the invention are characterized in that the bearings include a sleeve between the sliding elements and the shaft which is rotatable with the shaft.

1 20 In a preferred embodiment of the invention, the sleeve has a plurality of holes extending substantially in the axial direction of the sleeve through which the heat transfer medium is arranged to be conducted.

Another object of the invention is to fit the conical outer surface of the shaft into a cylindrical surface suitable for sliding bearings. This object is solved according to the invention so that the outer surface of the sleeve is substantially cylindrical, the inner surface being adapted to the shape of the outer surface of the shaft.

•

The dependent claims 2 to 6 disclose some preferred embodiments and structural embodiments of the plain bearing according to the invention.

35

The method according to the invention is characterized in that the method utilizes a sleeve having substantially axially extending holes, which sleeve is positioned between the shaft and the sliding elements, and that a cooling medium is passed through said axially extending holes.

The invention will now be described, by way of example, with reference to the figures in the accompanying drawings, in which:

Figure 1 is a schematic, partially cut-away end view of a prior art plain bearing 10.

Figure 2 is a schematic sectional view of a plain bearing according to an embodiment of the invention.

Figure 3 shows a schematic end view of the sleeve.

Figure 4 is a sectional view taken along line IV-IV in Figure 3.

. Fig. 2 schematically illustrates an embodiment of an exterior roller bearing of roller 20 according to the invention. The roller is designated by reference numeral 1. The axis of the roller is designated by reference numeral 2.

Although the plain bearing arrangement of the invention comprises. . 25 generally illustrates an arrangement with only one bearing element 3 corresponding to the uppermost vertical bearing element of Figure 1. The bearing elements 3 are mounted on the frame member or bearing bracket 5.

30

A sleeve 6 is disposed between the sliding elements 4 of said bearing elements 3 and the shaft 2 of the roller 1. As best seen in Figure 4, the hole 6 of the sleeve 6 is of conical cross-section. This conical surface 17 35 allows the sleeve 6 to be arranged axially around the conical portion 21 of the shaft 2 extending outside the roller 1 between the sliding elements 4 and the shaft 2.

104343 4

The sleeve 6 is secured around the shaft 2 by, for example, a wedge lock (not shown) such that the sleeve 6 rotates with the shaft. Axial movement can be prevented, for example, by means of a nut 20 around the shaft 2 with a nut 20. The outer surface 11 of the sleeve 6 has a substantially cylindrical cross-section. The lubricating oil film (not shown) between the shaft 2 and the sliding element 4 is between the cylindrical outer surface 11 of the sleeve 6 and the sliding surface of the sliding element 4.

10

Due to the conical nature of the shaft 2, the bearing elements 3 are previously slightly inclined with respect to the axis of rotation of the shaft 2, but due to the cylindricality of the outer surface 11 of the sleeve 6 according to the invention As a result, other special arrangements are avoided, for example with respect to the bearing bracket 5.

A plurality of '20 elongated holes 7 extending axially to the sleeve extend over most of the length of the sleeve 6.

Also, an annular groove 9 is provided on the end face 19 of the sleeve 6 extending around the circumference of the entire end face, in which the holes 7 are provided. 25 one end opens. The other end of the holes 7 opens through an additional hole 18 to the cylindrical outer surface 11 of the sleeve 6.

The cooling medium 8 is led into the holes 7 of the sleeve 6 from an external pressure source (not shown) at a suitably adjustable pressure. The cooling medium 8 is initially introduced into the feed channel 15, which in the embodiment of Figure 2 is a hole passed through a bearing bracket 5. The cooling medium 8 is introduced along the supply channel 15 into the flexible tube 14 extending the supply channel 15 and thereafter 35 via the positioning means 13 into the supply tube 10. A supply end 16 is connected to the supply tube 10 where the direction of the cooling medium 8 is approximated. The feed end 16 opens into the annular groove 9 of the sleeve 6 5 104343.

The shaft 2 rotating about its axis of rotation 22 rotates the sleeve 6, whereby the holes 7 in the sleeve rotate in turn at the feed end 16 of the feed tube 10 in the sleeve annular groove 9, whereby the cooling medium 8 moves from the feed head 16 to the holes 6 at one end of hole 7 through additional holes 18 on outer surface 11 of sleeve 6.

The positioning means 13 maintains a constant distance between the sleeve 6 and the feed pipe 10. The flexible tube 14 allows the supply tube 10 to move relative to the supply channel 15. Changes in distance can be caused by thermal expansion due to temperature changes in the sleeve 6 and shaft 2.

15

The function of the sleeve 6 and the cooling medium 8 is to cut off or substantially reduce the thermal energy flow from the shaft 2 to the bearing elements 3. The surface temperature of the roll in the thermo roll 1 can rise up to 200 ° C. 8, whereby the thermal energy flow from the shaft 2 to the sliding elements 4 is interrupted or substantially reduced. The problems of excessive heating of the lubricating oil film of the sliding elements 4 are thus eliminated, while its temperature remains low and substantially constant all the time in use.

The efficiency of the thermal energy flow cut-off is influenced by the temperature of the cooling medium 8, which is advantageous for the invention; in this embodiment is less than about 80 ° C, which is the normal maximum temperature of the lubricating oil forming lubricating oil between the sliding element 4 and the shaft 2. Preferably, the cooling medium is the same oil 35 used for lubrication, but other fluids may be used provided that the medium circulation is sufficiently insulated from the lubricating oil circuit of the sliding elements 4. The efficiency of cutting the thermal energy flow is also affected by the diameters of the holes 104343 6 7 of the sleeve 6 and their frequency in the circumference of the sleeve 6. Of course, these features can be changed as needed.

According to the invention, the sleeve 6 may be made of a heat-insulating material, whereby the holes 7 and their associated cooling medium 8 feeds may be omitted.

Claims (7)

An outer slide bearing, which surrounds the shaft (2) to a roller (1) in a paper / cardboard machine or a finishing machine, which has hydrostatic bearing elements (3) around the shaft (2) provided with sliding elements (4) arranged to be positioned about the axis (2) of the roller (1) for rotatingly supporting said axis (2) and thereby the roller (1) with respect to a frame member 10 (5), characterized in that: the bearing shows a sleeve (6) between the sliding elements (4) and the shaft (2), which is arranged to rotate with the shaft (2). Sliding bearing according to claim 1, characterized in that the sleeve (6) has a number of shafts (7) extending substantially in the axial direction of the sleeve (6), through which a heat transfer medium (8) is arranged to be fed. Sliding bearing according to claim 2, characterized in that at the end (19) of the sleeve (6) there is an annular cutter (9), to which said cooling medium (8) can be fed with the feeding means (10,14,15,16) of the medium. and that each shark (7) opens into the annular cutter (9) to guide the cooling medium (8) through the heels. Sliding bearing according to claim 1, characterized in that the outside (11) of the sleeve (6) is substantially cylindrical, the inside (17) being adapted to the shape on the outside (21) of the shaft. Sliding bearing according to any of claims 1-4, characterized in that the sleeve (6) is made of heat insulating material. 35 Sliding bearing according to any of the present claims, characterized in that the roller (1) is a heated roller. 104343 10 A method of cooling an outer slide bearing, which surrounds the shaft (2) to the roller (1), in particular a heated roller, in a paper / cardboard machine or a finishing machine, which slide bearing has hydrostatic bearing elements (3) around the shaft (2). ), which are provided with sliding elements (4) which are adapted to be positioned about the axis (2) of the roller (1) for rotatingly supporting said axis (2) and thereby the roller (1) with respect to the frame member (5). , characterized in that in the method a sleeve (6) is used which has a substantially shaft (7) which extends substantially in the axial direction, which sleeve (6) is arranged between the shaft (2) and the sliding elements (4), and that the in the axial direction extending the heel (7), cooling medium (8) is led. 15