Device and method for mounting a bearing on a seat

Abstract

A tool kit for mounting a bearing having an inner ring with a tapered bore onto a seat, the mounting being accomplished with the following: an adaptive sleeve interposed radially between the inner ring and the seat and comprising on its outer periphery a tapered portion (11) for mating with the tapered bore of the inner ring, a threaded part (12) extending away from the bearing in the axial direction is further arranged on the outer periphery of the bearing; the hydraulic nut (13) comprises a threaded hole (14) and a piston (15), and the piston can move in the axial direction so as to exert axial force on the side face of the bearing inner ring; and a hydraulic pump for establishing a hydraulic pressure inside the hydraulic nut, in which the tool kit comprises: a drive tube (16) axially interposed between the side of the bearing inner ring and the piston of the hydraulic nut; and a reaction sleeve interposed between the hydraulic nut and the fitting sleeve and including a first threaded portion engaged with the threaded portion of the fitting sleeve and a second threaded portion engaged with the threaded bore of the hydraulic nut.

Description

Technical Field

[0001] The present invention relates to a device for mounting a bearing (in particular a spherical roller bearing or a toroidal roller bearing) having an inner ring with a tapered bore onto a seating.

[0002] The present invention also relates to a method for mounting a bearing having an inner ring with a tapered bore onto a seating. Background Art

[0003] The SKF Drive-Up Method for mounting a rolling bearing with a tapered bore (i.e., a rolling bearing having a bore with a tapered surface in the inner ring) onto a seating is known.

[0004] For this purpose, as Figure 1 shown, a hydraulic nut 13 and an adapter sleeve 8 are used to mount a spherical roller bearing 1. The adapter sleeve includes a tapered portion 11 on its outer peripheral surface to cooperate with the tapered surface 6 of the bearing bore. The adapter sleeve also includes a threaded portion 12 for engaging with a threaded portion 14 disposed in the bore of the nut. A hydraulic pump 24 with a high-precision pressure gauge 25 is used to build pressure inside the nut for driving a piston 15 axially against the side surface of the bearing inner ring. A specific pressure calculated specifically for each bearing type enables the bearing to be precisely positioned at the starting point, from which the axial drive-up is measured with the aid of a dial indicator 26. By controlling the axial drive-up from this predetermined position, an appropriate fit is achieved.

[0005] In some applications, such as when the bearing is mounted inside a housing having a bore through which a shaft extends, there is not enough space for the hydraulic nut to engage inside the housing bore until it reaches the bearing.

[0006] The present invention aims to solve this problem. Summary of the Invention

[0007] It is an object of the present invention to provide a toolkit for mounting a bearing having an inner ring with a tapered bore onto a seating, the mounting being achieved by using an adapter sleeve, a hydraulic nut, and a hydraulic pump.

[0008] The adapter sleeve is radially interposed between the inner ring and the seating. The adapter sleeve includes a tapered portion on its outer periphery for mating with the tapered bore of the inner ring. The adapter sleeve further includes a threaded portion on its outer periphery for extending axially away from the bearing.

[0009] The hydraulic nut includes a threaded bore and a piston that can move axially to apply an axial force on the side surface of the inner ring of the bearing.

[0010] The hydraulic pump is used to establish hydraulic pressure inside the hydraulic nut.

[0011] The tool kit according to the present invention includes a drive tube and a reaction sleeve.

[0012] The drive tube is axially interposed between the side surface of the inner ring of the bearing and the piston of the hydraulic nut.

[0013] The reaction sleeve is interposed between the hydraulic nut and the adapter sleeve. The reaction sleeve includes a first threaded portion that engages with the threaded portion of the adapter sleeve. The reaction sleeve further includes a second threaded portion that engages with the threaded bore of the hydraulic nut.

[0014] In a preferred embodiment of the present invention, the drive tube and the reaction sleeve are made of AISI 4140 alloy steel or similar materials.

[0015] In a preferred embodiment, the reaction sleeve 17 includes a knurled surface 27 axially located between the first threaded portion 18 and the second threaded portion 19.

[0016] In a preferred embodiment of the present invention, the tool kit further includes a contact ring that is axially interposed between the drive tube and the side surface of the inner ring of the bearing.

[0017] In a preferred embodiment of the present invention, the contact ring is made of AISI 4140 alloy steel or similar materials.

[0018] In a preferred embodiment of the present invention, the contact ring has a tapered portion on the side that engages with the side surface of the inner ring of the bearing to prevent any contact with the seal or cage or rolling elements of the bearing.

[0019] Another object of the present invention is a method of installing a bearing having an inner ring with a tapered bore onto a seating using the tool kit according to the present invention.

[0020] In a preferred embodiment of this method, the contact ring is not used.

[0021] In another preferred embodiment of the present method, a contact ring is used. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] The present invention will now be explained with reference to the drawings, which are illustrative examples and do not limit the purpose of the present invention, wherein:

[0023] - Figure 1 shows the SKF propulsion method using a conventional tool kit, and

[0024] - Figure 2 shows the SKF propulsion method using a tool kit according to the present invention.

[0025] LIST OF REFERENCE NUMERALS

[0026] 1 Bearing

[0027] 2 Inner Ring

[0028] 3 Outer Ring

[0029] 4 Rolling Element

[0030] 5 Cage

[0031] 6 Tapered Hole

[0032] 7 Seat

[0033] 8 Adaptor Sleeve

[0034] 9 Cylindrical Hole

[0035] 10 Cylindrical Surface

[0036] 11 Tapered Portion

[0037] 12 Threaded Portion

[0038] 13 Hydraulic Nut

[0039] 14 Threaded Hole

[0040] 15 Piston

[0041] 16 Drive Tube

[0042] 17 Reaction Sleeve

[0043] 18 First Threaded Portion

[0044] 19 Second Threaded Portion

[0045] 20 Cylindrical Hole

[0046] 21 Cylindrical Surface

[0047] 22 Contact Ring

[0048] 23 Tapered portion

[0049] 24 Hydraulic pump

[0050] 25 Pressure gauge

[0051] 26 Dial indicator

[0052] 27 Knurled surface

[0053] L Side of the housing Detailed implementation manner

[0054] Figure 2 The bearing 1 mounted on the seat 7 is shown.

[0055] The bearing is a rolling bearing and includes an inner ring 2, an outer ring 3, rolling elements 4 in the form of spherical rollers located between the inner ring and the outer ring, and a cage 5 for holding the rollers in place at uniform intervals in the circumferential direction. The inner ring 2 has a tapered hole 6.

[0056] To mount the bearing on a seat (such as a shaft or sleeve as shown in the figure), several elements are used.

[0057] The first element used is an adapter sleeve 8 that is radially interposed between the inner ring and the seat.

[0058] The adapter sleeve 8 also includes a tapered portion 11 on its outer periphery for mating with the tapered hole 6 of the bearing inner ring.

[0059] The adapter sleeve 8 also includes a threaded portion 12 on its outer periphery that extends axially away from the bearing.

[0060] Advantageously, the adapter sleeve 8 has a cylindrical hole 9 for direct contact with the cylindrical surface 10 of the seating 7.

[0061] The second element used is a hydraulic nut 13. The hydraulic nut includes a threaded hole 14 and a piston 15 that can move axially to apply an axial force on one side of the bearing inner ring, and this side of the inner ring extends radially.

[0062] The hydraulic nut also includes a dial indicator, such as Figure 1 the dial indicator shown.

[0063] The third element used is a hydraulic pump, such as Figure 1 the hydraulic pump shown, for generating hydraulic pressure inside the hydraulic nut to axially actuate the piston, and the piston is also used during the installation of the bearing.

[0064] Advantageously, the pump is a manual pump and includes a high-precision pressure gauge.

[0065] In addition to the components mentioned above, a toolkit is also used to install the bearing.

[0066] The toolkit includes a drive tube 16 that axially intervenes between the side of the inner ring of the bearing and the piston of the hydraulic nut.

[0067] The toolkit also includes a reaction sleeve 17 that intervenes between the hydraulic nut 13 and the adapter sleeve 8.

[0068] The reaction sleeve 17 includes a first threaded portion 18 that is to engage with the threaded portion 12 of the adapter sleeve 8.

[0069] The first threaded portion 18 is located on the inner periphery of the reaction sleeve 17.

[0070] The reaction sleeve 17 also includes a second threaded portion 19 that is to engage with the threaded hole 14 of the hydraulic nut 13.

[0071] The second threaded portion 19 is located on the outer periphery of the reaction sleeve 17.

[0072] The reaction sleeve is radially intervening between the seat and the drive tube.

[0073] Advantageously, the reaction sleeve 17 has a cylindrical hole 20 for direct contact with the cylindrical surface 21 of the seat 7.

[0074] Advantageously, the reaction sleeve has a knurled surface 27 on its outer periphery. Due to its knurled surface, the reaction sleeve can be easily handled.

[0075] Due to the toolkit, the hydraulic nut can be held at a greater axial distance from the bearing compared to the case without the toolkit, so as not to interfere with mechanical components around the bearing, such as the housing in which the bearing is installed.

[0076] Due to the present invention, the bearing can be installed inside the housing while holding the hydraulic nut outside the housing, as Figure 2 shown, where the line L represents the side of the base of the housing.

[0077] Due to the present invention, the bearing can be replaced in situ, thus significantly reducing the downtime during maintenance.

[0078] In a preferred embodiment of the present invention, the drive tube 16 and the reaction sleeve 17 are made of AISI 4140 alloy steel. Calculations have shown that this material is suitable for properly transmitting the axial force to the bearing.

[0079] Optionally, the tool kit further includes a contact ring 22 to be axially interposed between the drive tube 16 and the side surface of the inner ring of the bearing, so as to receive the driving force from the piston.

[0080] In a preferred embodiment of the present invention, the contact ring 22 is made of AISI 4140 alloy steel.

[0081] In a preferred embodiment of the present invention, the contact ring has a tapered portion 23 on the side to be engaged with the side surface of the inner ring of the bearing, so as to prevent any contact with the seal or cage or rolling elements of the bearing.

[0082] A method for installing the bearing 1 onto the seat 7 by using the tool kit according to the present invention will now be described.

[0083] When the contact ring 22 is not used, the method includes the different steps (a), (b), (c), (d), (e), (f) and (g) described below.

[0084] Step (a): Install the adapter sleeve 8 onto the seat 7. Then install the bearing 1 onto the adapter sleeve 8 such that the tapered hole 6 of the inner ring 2 of the bearing mates with the tapered portion 11 of the adapter sleeve 8.

[0085] Step (b): Install the reaction sleeve 17 by engaging the first threaded portion 18 of the reaction sleeve 17 with the threaded portion 12 of the adapter sleeve 8.

[0086] Preferably, due to the knurled surface 27 of the reaction sleeve 17, step (b) is completed by hand-tightening.

[0087] Step (c): Install the drive tube 16 around the reaction sleeve 17 to contact the inner ring 2 of the bearing.

[0088] Step (d): Install the hydraulic nut 13 such that the threaded hole 14 of the hydraulic nut 13 engages with the second threaded portion 19 of the reaction sleeve 17 until the piston 15 contacts the drive tube 16.

[0089] Step (e): Generate a specific pressure inside the hydraulic nut 13 to generate the piston driving force required to establish the "starting point" (according to the standard drive-up method that correlates the force with the gauge pressure depending on the piston surface area).

[0090] Before step (e), connect the hydraulic pump to the hydraulic nut.

[0091] Step (f): Reset the dial indicator mounted on the hydraulic nut and use the hydraulic pump to achieve the pre-displacement of the inner ring (so-called advance distance). Then release the pressure and remove the hydraulic nut 13, the drive tube 16 and the reaction sleeve 17.

[0092] Step (g): Install a tab washer (not shown) and a lock nut (not shown) on the threaded portion 12 of the adapter sleeve 8 and tighten against the side surface of the bearing inner ring 2 to lock the position of the bearing 1 on the seat 7.

[0093] When using the contact ring (22), the method for installing the bearing onto the seat includes the different steps (a’), (b’), (c’), (d), (e), (f’) and (g) described below.

[0094] Step (a’): Install the adapter sleeve 8 on the seat 7. Then install the bearing 1 on the adapter sleeve 8 such that the tapered hole 6 of the bearing inner ring 2 mates with the tapered portion 11 of the adapter sleeve 8 and position the contact ring 22 against the bearing inner ring 2.

[0095] Step (b’): Install the reaction sleeve 17 by engaging the first threaded portion 18 of the reaction sleeve 17 with the threaded portion 12 of the adapter sleeve 8 until it is in firm contact with the contact ring 22.

[0096] Preferably, due to the knurled surface 27 of the reaction sleeve 17, step (b) is completed by hand-tightening.

[0097] Step (c’): Install the drive tube 16 around the reaction sleeve 17 to contact the contact ring 22.

[0098] Step (d): Install the hydraulic nut 13 such that the threaded hole 14 of the hydraulic nut 13 engages with the second threaded portion 19 of the reaction sleeve 17 until the piston 15 contacts the drive tube 16.

[0099] Step (e): Generate a specific pressure inside the hydraulic nut 13 to generate the piston driving force required to establish the “starting point” (according to the standard advancement method that correlates force with the gauge pressure depending on the piston surface area).

[0100] Before step (e), connect the hydraulic pump to the hydraulic nut.

[0101] Step (f’): Reset the dial gauge mounted on the hydraulic nut and use a hydraulic pump to effect a pre-displacement (so-called push distance) of the inner ring. Then release the pressure and remove the hydraulic nut 13, the drive tube 16, the reaction sleeve 17 and the contact ring 22.

[0102] Step (g): Mount a tab washer (not shown) and a lock nut (not shown) on the threaded portion 12 of the adapter sleeve 8 and tighten against the side face of the bearing inner ring 2 to lock the position of the bearing 1 on the seat 7.

[0103] The choice of whether to use the contact ring 22 for mounting the bearing depends on the construction and dimensions of the bearing and the seat.

[0104] A specific pressure inside the hydraulic nut is pre-determined for the bearing to be mounted and can vary according to the different bearing types or dimensions.

[0105] This specific pressure enables precise positioning of the bearing from a starting point from which the axial push is measured.

[0106] By controlling the axial push during bearing mounting, proper seating is achieved.

[0107] Thanks to the present invention, the bearing can be optimally mounted, i.e., for example, the clearance inside the bearing is reduced by 0.45‰.

[0108] It has been found that the components of the tool kit are fail-safe and their presence (as additional elastic members) produces a negligible additional elastic deformation which does not affect the standard push distance calculated by the SKF software related to the direct contact between the hydraulic nut piston and the bearing inner ring.

[0109] The method described above is advantageously used for an “in situ” replacement of a bearing located in a housing, the side of which is represented by Figure 2 the line L thereon. In this case, the bearing, the adapter sleeve and the housing base must be slid together into position, where the shaft is jacked up slightly above its nominal height.

Claims

1. A tool kit for mounting a bearing (1) having an inner ring (2) with a tapered bore (6) on a seat (7), the mounting being accomplished using: - an adapting sleeve (8) radially interposed between the inner ring and the seat and comprising, on the outer periphery of the adapting sleeve (8), a tapered portion (11) for mating with the tapered hole (6) of the inner ring (2) and a threaded portion (12) for extending axially away from the bearing, - a hydraulic nut (13) comprising a threaded hole (14) and a piston (15) movable in the axial direction to exert an axial force on the side of the inner ring of the bearing, and - a hydraulic pump for building up hydraulic pressure inside the hydraulic nut (13), It is characterized in that The tool kit includes: - a drive tube (16) axially interposed between the side surface of the bearing inner ring (2) and the piston (15) of the hydraulic nut (6), and - a reaction sleeve (17) interposed between the hydraulic nut (13) and the adapter sleeve (8) and comprising a first threaded portion (18) engaging with the threaded portion (12) of the adapter sleeve (8) and a second threaded portion (19) engaging with the threaded hole (14) of the hydraulic nut (13).

2. The tool kit according to claim 1, characterized in that: The drive tube (16) and the reaction sleeve (17) are made of AISI 4140 alloy steel.

3. The tool kit according to claim 1 or 2, characterized in that: The reaction sleeve (17) includes a knurled surface (27) axially between the first threaded portion (18) and the second threaded portion (19).

4. A tool kit according to any preceding claim, characterised in that The tool kit further comprises a contact ring (22) which is axially interposed between the drive tube (16) and the side surface of the bearing inner ring to receive the driving force from the piston.

5. The tool kit according to claim 4, characterized in that The contact ring (22) has a tapered portion (23) on the side engaging with the side of the bearing inner ring so as to prevent any contact with the seal or cage or rolling elements of the bearing.

6. The tool kit according to claim 4 or 5, characterized in that: The contact ring (22) is made of AISI 4140 alloy steel.

7. A method for mounting a bearing (1) having an inner ring (2) with a tapered bore (6) in a seat (7) using a tool kit according to any one of claims 1 to 3, characterized in that The method comprises the following steps: (a) installing the adapter sleeve (8) on the seat (7), and then installing the bearing (1) on the adapter sleeve (8) so that the tapered hole (6) of the bearing inner ring (2) fits with the tapered portion (11) of the adapter sleeve (8), (b) mounting the reaction sleeve (17) by engaging the first threaded portion (18) of the reaction sleeve (17) on the threaded portion (12) of the adapter sleeve (8), (c) installing the drive tube (16) around the reaction sleeve (17) so as to contact the bearing inner ring (2), (d) installing the hydraulic nut (13) so that the threaded hole (14) of the hydraulic nut (13) engages with the second threaded portion (19) of the reaction sleeve (17) until the piston (15) comes into contact with the drive tube (16), (e) generating a specific pressure inside the hydraulic nut (13) by means of the hydraulic pump according to a propulsion method that relates the force to the gauge pressure that depends on the piston surface area, so that the piston driving force required to establish the starting point is generated, (f) resetting the dial gauge mounted on the hydraulic nut and using the hydraulic pump to achieve a predetermined displacement of the inner ring, the so-called advancement distance; then releasing the pressure and removing the hydraulic nut (13), the drive tube (16) and the reaction sleeve (17), (g) Installing a tab washer and a locking nut on the threaded portion (12) of the adapter sleeve (8) and tightening against the side of the bearing inner ring (2) to lock the position of the bearing on the seat.

8. A method for mounting a bearing (1) having an inner ring (2) with a tapered bore (6) in a seat (7) using a tool kit according to any one of claims 4 to 6, characterized in that The method comprises the following steps: (a') installing the adapter sleeve (8) on the seat (7), and then installing the bearing (1) on the adapter sleeve (8) so that the tapered hole (6) of the bearing inner ring (2) fits with the tapered portion (11) of the adapter sleeve (8), and the contact ring (22) is positioned against the bearing inner ring (2), (b') installing the reaction sleeve (17) by engaging the first threaded portion (18) of the reaction sleeve (17) on the threaded portion (12) of the adapter sleeve (8) until it is in firm contact with the contact ring (22), (c') installing the drive tube (16) around the reaction sleeve (17) so as to be in contact with the contact ring (22), (d) installing the hydraulic nut (13) so that the threaded hole (14) of the hydraulic nut (13) engages with the second threaded portion (19) of the reaction sleeve (17) until the piston (15) comes into contact with the drive tube (16), (e) generating a specific pressure inside the hydraulic nut (13) by means of the hydraulic pump according to a propulsion method that relates the force to the gauge pressure that depends on the piston surface area, so that the piston driving force required to establish the starting point is generated, (f') resetting the dial gauge mounted on the hydraulic nut and using the hydraulic pump to achieve a predetermined displacement of the inner ring, the so-called push-in distance; then releasing the pressure and removing the hydraulic nut, the drive tube, the reaction sleeve and the contact ring, (g) Install a tab washer and lock nut on the threaded portion of the adapter sleeve and tighten against the side of the bearing inner race to lock the position of the bearing on the seat.

9. The method according to claim 7 or 8, characterized in that: Due to the knurled surface (27), the reaction sleeve (17) is finger-tight.

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