GB2439149A

GB2439149A - A bearing chamber assembly

Info

Publication number: GB2439149A
Application number: GB0611996A
Authority: GB
Inventors: Alan Roddis
Original assignee: AES Engineering Ltd
Current assignee: AES Engineering Ltd
Priority date: 2006-06-17
Filing date: 2006-06-17
Publication date: 2007-12-19
Also published as: GB0611996D0

Abstract

A bearing chamber of a rotating piece of equipment, such as a centrifugal pump, comprises a housing 12 having located therein bearings 13, 14 and seals (16, 17, Fig 1) and a drive shaft 11 extending through the housing 12 and mounted for rotation within the bearings 13, 14 and sealed to the housing 12 by the seals (16, 17, fig 1). A bearing cap 30 is provided and is constructed so as to maximise the surface area in contact with a lubrication media such as oil so as to enhance heat dissipation. The bearing cap 30 preferably includes a series of radially and/or longitudinally extending castellations 31 adjacent to the lubrication media which act as an effective heat transfer. The surface of the bearing cap 30 facing outwardly from the bearings 13, 14 may have an external profile that is configured in such a way to re-direct any high velocity fluid away from the bearing seal (16, 17, fig 1).

Description

BEARING CAP

Field of Invention

The present invention relates to rotating equipment, specifically centrifugal pumps.

More particularly, the present invention relates to the bearing chamber of the rotating equipment and the effective heat transfer/exchange of the lubrication media contained within. Furthermore, the invention relates to the effective re-distribution of high-pressure water jet, directed at said bearing chamber.

Background of the Invention

An example of a piece of rotating equipment which has a bearing chamber is a Centrifugal Pump In such equipment, each bearing arrangement typically consists of at least one bearing housed in a bearing chamber. Said bearing occupies the radial space between the stationary housing and rotating shaft. Said bearing is lubricated and sealed between the rotor to stator interface to prevent the ingress or egress of a fluid or solid to the bearing cavity, since such unwanted material results in the deterioration of equipment life.

Bearing seals are often also referred to as bearing protectors or bearing isolators, however, the use of such seals extends well beyond the protection of a bearing in rotating equipment. Accordingly, while reference will be made below to bearing protectors, it should be understood that this term is used, as far as the invention is concerned, in connection with such having wider uses.

* SS * * * * S.* * .. Certain pumps, such as the 3196 model from ITT Industries / Goulds, contain the 5::. bearing seal in the adapter frame rather than the bearing chamber. Clearly, if the S..

bearing chamber is inventoried as an independent subassembly, the bearings *3t contained with the bearing chamber are not sealed whilst stored. Since evidence * : * suggests that only a small about of moisture can dramatically reduce bearing life, it is considered advantageous if said bearing chamber can be stored with an integral seal installed.

Certain other pumps, incorporate a bearing cap which contains a bearing seal and which is mounted onto the beanng chamber to protect the bearings. During dynamic equipment operation, the bearing lubrication fluid heats and expands. On severe applications, the lubrication fluid can get considerably hot given high shaft speed and energy input from both the bearings and an integral splash ring.

As bearing lubrication, fluid gets hot, its lubrication properties change, and often the effectiveness of the lubrication reduces since the lubrication fluid may also deteriorate with temperature.

It is considered to be advantageous, if said bearing chamber, and more specifically one or more bearing caps, can effectively dissipate/transfer the heat from the lubrication media inside the bearing chamber to the atmosphere outside the bearing chamber.

Often, rotating equipment is cleaned, in operation, using high pressure cleaning equipment, typically directing a high-pressure water jet at the bearing chamber.

Clearly, preventing this moisture from entering the bearing chamber is a primary consideration for the bearing seal.

It is considered to be further advantageous, if said bearing chamber, and more specifically one of more bearing caps, can effectively re-distribute any such directed water jet, away from the bearing seal and/or any other such sealing interface which may be considered an entry point for moisture ingress into the bearing chamber.

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..... Statements of the Invention

* *. According to the present invention, there is provided a bearing chamber of a rotating piece of equipment. Said bearing chamber comprises of a housing having located therein bearings and seals, and a drive shaft extending through the housing and mounted for rotation within said bearings and sealed to the housing by said seals, : whereby said stationary members of the assembly are constructed to maximise the surface area in contact with the lubrication media employed to lubricate the bearings.

Preferably, said seals are mounted in one or more bearing caps which, in turn, mount to the housing, and said bearing cap has a series of radially and/or longitudinally extending castellations, adjacent to said bearing lubrication media, said castellations maximising the surface area in contact with the lubrication media thus acting as an effective heat transfer system to atmosphere.

Preferably, on the outwardly facing side of the bearing cap, opposite to the lubrication media side, said bearing cap external profile is configured in such a way to re-direct any such high velocity fluid away from the bearing seal and/or sealing interfaces.

Preferably, said external profile of the bearing cap, has a series of substantially concentric contours, comprising of circumferential grooves radially displaced to the centre position of said bearing cap, said grooves are preferably abruptly terminated at the relative 6 o'clock position on the end view of the bearing cap with a communication means herewith referred as a slot. Therefore, in operation, water entering said circumferential grooves is directed around the circumference of the groove, away from the somewhat centrally displaced bearing seal, before exiting said grooves at the 6 o'clock communication slot.

Preferably, said bearing cap is sealed to the bearing chamber by a sealing member which is radially positioned to provide a sealing means for any and all areas of moisture ingress into the bearing chamber.

Preferably, said sealing member is a solid toroidal sealing member.

* S. S * S S...

* ** Preferably, said bearing cap is positively secured to the bearing chamber by at least one longitudinal bolt/screw. S..

*.*t Preferably, at an outer most radial surface of said bearing cap is a location feature, said location feature is employed to locate a further member of the rotating equipment assembly, namely the frame adapter.

Preferably, said bearing cap has at least one surface discontinuity adjacent to the lubrication media, said surface discontinuity namely a slot, communicates from a radially outward position of the bearing cap to a radially inward position, hence can be employed to communicate externally applied bearing lubrication media between the two radial positions.

Preferably, said bearing cap has at least one circumferential mark sited to advise the operator the correct assembly orientation of said bearing cap to said bearing chamber.

Preferably, at least three longitudinal bolts are employed to secure said bearing cap to said bearing chamber, and preferably said bolts unequally circumferentially spaced so that said bearing cap can only be assembled onto said bearing chamber in one rotational orientation, thereby ensure the 6 o'clock communication slot is always positioned at the 6 o'clock point.

Brief Description of the Drawings

By means of example only, the following drawings are intended to show the various embodiments of the invention, however, clearly further configurations which achieve the same/similar outcome are also anticipated.

Figure 1-shows a cross section of a prior-art centrifugual pump Figure 2-shows a cross section of the centrifugual pump of the invention : .2 Figure 3-corresponds to Figure 2 and shows a cross section of the bearing chamber S...

..... subassembly of the invention : ** Figure 4-corresponds to Figure 3 and shows an end view of the bearing cap of the S...

* invention.

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Detailed Description of the Invention

The invention will now be described by way of example only, with reference to the accompanying drawings.

From Figure 1, a centrifugal pump 10 has a rotating shaft 11 and a stationary housing 12. Said housing 12, houses bearings 13 and 14 which are radially connected to the shaft 11. The impeller 15 is longitudinally and rotationally connected to the shaft 11. The shaft 11 is also rotationally coupled to bearing seals 16 and 17 and mechanical seal 18.

Bearing lubrication media 19 is positioned in the inner most radial surface 20 of the bearing chamber 12. Said seals 16 and 17 prevent said bearing lubrication media 19 from being contaminated.

As shown, the bearing seal 17 is mounted in adapter frame 21, therefore, if the bearing chamber 12, bearings 13 and 14 and shaft 11 assembly is stored without frame adapter 21, the inner most surface 20 of bearing chamber 12 and bearings 14 and 13 can get contaminated with foreign debris before the equipment is operational, given the fact that the bearing seal 17 is not part of said assembly.

Figure 2, shows an embodiment of the invention, in that bearing chamber 12 has a bearing cap 30 mounted as an integral part of the bearing chamber 12 assembly.

As bearing seal 17 is mounted in bearing cap 30, therefore, when stored as a sub-assembly, said bearings 14 and 13 are totally sealed, as shown in Figure 3. * **. * S * ***

* *. From Figure 3, said bearing cap 30 has a series of radially and/or longitudinally extending castellations 31, adjacent to said bearing 14 and bearing lubrication media 55* 19. Said castellations 31 maximise the surface area in contact with the lubrication * media 19 thus acting as an effective heat transfer system to atmosphere. *

S.....

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On the outwardly facing side of the bearing cap 30, opposite to the lubrication media 19 side, is an external profile 32 of said bearing cap 30, configured in such a way to re-direct any such high velocity fluid away from the bearing seal 17 and/or sealing interfaces.

From Figure 4, preferably, said external profile 32 of the bearing cap 30, has a series of substantially concentric contours, comprising of circumferential grooves 40 radially displaced to the centre position of said bearing cap 30.

Said grooves 40 are preferably abruptly terminated 41 at the relative 6 o'clock position on the end view of the bearing cap 30 with a communication means herewith referred as a slot 42. Therefore, in operation, water entering said circumferential grooves 40 is directed around the circumference of the groove 40, away from the somewhat centrally displaced bearing seal 17, before exiting said grooves at the 6 o'clock communication slot 42.

From Figure 3, preferably, said bearing cap 30 is sealed to the bearing chamber 12 by a sealing member 50 which is radially positioned to provide a sealing means for any and all areas of moisture ingress into the bearing chamber 12.

Said sealing member 50 is a solid toroidal sealing member, herewith referred as an elastomer.

Said bearing cap 30 is positively secured to the bearing chamber by at least one longitudinal bolt/screw 51. Preferably, said bolt 51 incorporates a sealing washer 52.

From Figure 4, preferably, at least three longitudinal bolts 51 are employed to secure Is..

said bearing cap 30 to said bearing chamber 12, and preferably said bolts 51 * *. unequally circumferentially spaced, in that angle @ is not equal to 120 degrees. This provides the advantage that said bearing cap 30 can only be assembled onto said *.

bearing chamber 12 in one rotational orientation, thereby ensure the 6 o'clock *: communication slot 42 is always positioned at the 6 o'clock point.

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From Figure 2, preferably, at an outer most radial surface of said bearing cap 30 is a location feature 60, said location feature is employed to locate a further member of the rotating equipment assembly, namely the frame adapter 21.

From Figure 3, preferably, said bearing cap 30 has at least one surface discontinuity adjacent to the lubrication media. Said surface discontinuity namely a slot 70, communicates from a radially outward position 71 of the bearing cap 30 to a radially inward position 72, hence can be employed to communicate externally applied bearing lubrication media, for example via onfice 73 between the two radial positions 71 and 72.

It will be obvious to the experienced reader, that the various embodiments of the invention offer clear advantages for all types of rotating equipment, specifically centrifugal pumps and more specific models such as the ITT Industries Goulds 3196 range and Peerless Pumps 8196 range. S. * S * *.* S... * S

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Claims

CLAIMS

1. A bearing chamber of a rotating piece of equipment, comprising of a housing having located therein bearings and seals, and a drive shaft extending through the housing and mounted for rotation within said bearings and sealed to the housing by said seals, whereby said stationary members of the assembly are constructed to maximise the surface area in contact with the lubrication media employed to lubricate the bearings.
2. A bearing cap according to Claim 1, whereby said seals are mounted in said cap, and said bearing cap, mounts to the housing, and said bearing cap has a series of radially and/or longitudinally extending castellations adjacent to said bearing lubrication media, said castellations maximising the surface area in contact with the lubrication media thus acting as an effective heat transfer system to atmosphere.
3. A bearing cap according to Claim 1 or 2, whereby on the outwardly facing side of the bearing cap, opposite to the lubrication media side, said bearing cap external profile is configured in such a way to re-direct any such high velocity fluid away from the bearing seal and/or sealing interfaces.
4. A bearing cap according to any preceding claims, whereby said external profile of the bearing cap has a series of substantially concentric contours, comprising of circumferential grooves radially displaced to the centre position of said bearing cap, I.e. * I III.

* *.
5. A bearing cap according to any preceding claims, whereby said grooves are abruptly terminated at the relative 6 o'clock position on the end view of the bearing cap with a communication means herewith referred as a slot. * . * a * S.

6. A bearing cap according to any preceding claims, whereby said bearing cap is sealed to the bearing chamber by a sealing member which is radially positioned to provide a sealing means for any and all areas of moisture ingress into the bearing chamber.

7. A bearing cap according to any preceding claims, whereby said sealing member is a solid toroidal sealing member.

8. A bearing cap according to any preceding claims, whereby said bearing cap is positively secured to the bearing chamber by at least one longitudinal bolt/screw.

9. A bearing cap according to any preceding claims, whereby at an outer most radial surface of said bearing cap is a location feature, said location feature is employed to locate a further member of the rotating equipment assembly, namely the frame adapter.

10.A bearing cap according to any preceding claims, whereby said bearing cap has at least one surface discontinuity adjacent to the lubrication media, said surface discontinuity namely a slot, communicates from a radially outward position of the bearing cap to a radially inward position, hence can be employed to communicate externally applied bearing lubrication media between the two radial positions.

1 l.A bearing cap according to any preceding claims, whereby said bearing cap has at least one circumferential mark sited to advise the operator the correct assembly orientation of said bearing cap to said bearing chamber.

12.A bearing cap according to any preceding claims, whereby at least three longitudinal bolts are employed to secure said bearing cap to said bearing chamber, said bolts unequally circumferentially spaced so that said bearing cap S...

can only be assembled onto said bearing chamber in one rotational orientation, thereby ensure the 6 o'clock communication slot is always positioned at the 6 S...

* o'clock point.

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*:.:o 13.An rotating piece of equipment, according to Claim I and substantially as herein described.

14.A rotating piece of equipment, substantially described herein with reference to figures 2 to 4 of the accompanying drawings.