JP5371615B2 - Bearing housing - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To prevent uplifting of a bottom plate of a bearing box body caused by a thermal elongation difference to prevent misalignment of a rotational shaft borne and supported by the bearing box. <P>SOLUTION: The bearing box 4 includes: a bearing box body 11 having a housing part 11a housing a bearing and a bottom plate 11b, installed on a base through a base plate, and having a square shape in a planner view; and an upper lid covering an upper part of the bearing box body 11. A plurality of reinforcement ribs 14 are disposed to connect side faces of curved leg bases 13 disposed at four corners of the bearing box body 11 with the bottom plate 11b, and a plurality of connection ribs 15 are disposed to connect side faces of the housing part 11a with the curved leg bases 13. <P>COPYRIGHT: (C)2011,JPO&amp;INPIT

Description

  The present invention relates to a bearing box, and more particularly to a bearing box disposed between a turbine and a compressor of a power generation system.

  As a bearing box disposed between a turbine and a compressor of a power generation system, for example, the one disclosed in Patent Document 1 is known.

JP 2002-317603 A

By the way, each of the turbine and the compressor disclosed in Patent Document 1 is incidentally and integrally provided in the bearing box via a claw foot portion extending from the lower compartment main body portion (casing) along the axial direction of the rotation shaft. It is installed on the cat footrest.
Further, during operation of the power generation system, the turbine casing and the compressor casing are at a high temperature (at least 100 ° C. or higher), so that a large difference in thermal expansion occurs in the cat leg portion incidentally and integrally provided in these casings.
On the other hand, the bearing box including the cat footrest is a low-temperature (room temperature to about 30 ° C.) because the bearings (journal bearing and thrust bearing) housed in the bearing box serve as a heat source, but the periphery is oil-cooled. The thermal elongation is slight.

  As a result, a large horizontal thermal expansion difference (direction perpendicular to the axis direction of the rotation axis) occurs between the claw foot and the claw foot platform, and this thermal expansion difference causes frictional force on the contact surface between the claw foot portion and the claw foot platform. (A force having a value obtained by multiplying the casing weight and the thrust load by the friction coefficient) is generated. As shown in FIG. 9, this frictional force acts on the contact surface 13 a between the claw foot portion (not shown) located at a position higher than the bottom plate 11 b of the bearing box body 100 and the claw foot platform 13. This causes a rotational moment with the bottom (bottom) of the fulcrum as a fulcrum.

When such a rotational moment is generated, the entire bearing box body is deformed into a convex bowl shape, and the bottom plate 11b of the bearing box body 100 is lifted, and the bearing housed therein is lifted upward, The rotating shaft (more specifically, the rotating shaft of the turbine, the rotating shaft of the compressor, and the connecting shaft that connects these rotating shafts) is lifted upward, resulting in misalignment of the rotating shaft.
Such misalignment occurs between the rotating part (rotor surface, blade tip, etc.) and the stationary part (inner surface of the casing, blade ring, stationary blade, gas seal, etc.) inside the turbine casing and the compressor casing. It may cause an increase / decrease in clearance, reduce the performance of the turbine and the compressor, and possibly cause internal contact, which may hinder the operation of the power generation system.

  The present invention has been made in view of the above circumstances, and can prevent the bottom plate of the bearing box body from being lifted due to a difference in thermal expansion, and can prevent misalignment of the rotary shaft supported by the bearing box. An object is to provide a bearing housing.

The present invention employs the following means in order to solve the above problems.
Bearing box according to the present invention includes a housing portion and the bottom plate for accommodating the bearing, the bearing housing body having a rectangular shape in plan view which is installed on a foundation via a base plate, covers the upper side of the bearing housing body A bearing box provided with an upper lid , wherein a space is formed between a side surface of the claw footrest provided at each of the four corners of the bearing box body and a side surface of the housing portion, and the four corners of the bearing box body A plurality of reinforcing ribs for connecting the side surface of the claw footrest and the bottom plate, respectively, and a plurality of connecting portions for connecting the side surface of the accommodating portion, the side surface of the claw footrest , and the upper surface of the bottom plate. A sheet of connecting ribs is provided.

  According to the bearing box of the present invention, the entire bearing box body is deformed upward by the difference in thermal expansion, the bottom plate of the bearing box body is lifted, and the bearing housed therein is lifted upward. At the same time, the rotation shaft supported by the bearing can be lifted upward to prevent misalignment of the rotation shaft.

  Since the power generation system according to the present invention includes a bearing box that prevents misalignment of the rotating shaft, the rotating part (rotor surface, blade tip, etc.) and the stationary part (in the turbine casing and the compressor casing) ( Increase or decrease in contact with the casing, blade ring, inner surface of the stationary blade, gas seal, etc., contact, etc. can be prevented, performance degradation of the turbine and compressor can be prevented, and power generation system Reliability can be improved.

  According to the present invention, it is possible to prevent the bottom plate of the bearing box main body from being lifted due to a difference in thermal expansion, and it is possible to prevent misalignment of the rotating shaft supported by the bearing box.

It is a principal part perspective view of the electric power generation system which comprised the bearing box which concerns on this invention. It is sectional drawing which cut | disconnected FIG. 1 along the axial direction of a rotating shaft. It is the front view which looked at the bearing housing body of the bearing housing concerning one embodiment of the present invention from the front. It is the front view which looked at the bearing box main body of the bearing box which concerns on 1st reference embodiment of this invention from the front. It is the front view which looked at the bearing box main body of the bearing box which concerns on 2nd reference embodiment of this invention from the front. It is a perspective view which shows the outline of the bearing box main body of the bearing box which concerns on 3rd reference embodiment of this invention. It is the front view which looked at the bearing box main body of the bearing box which concerns on 4th reference embodiment of this invention from the front. It is the front view which looked at the bearing case main body of the bearing case which concerns on 5th reference embodiment of this invention from the front. It is a figure for demonstrating the deformation | transformation of the bearing box main body by a thermal expansion difference, Comprising: It is the front view which looked at the bearing box main body of the conventional bearing box from the front.

Hereinafter, an embodiment of a bearing housing according to the present invention will be described with reference to FIGS.
1 is a perspective view of a main part of a power generation system including a bearing box according to the present invention, FIG. 2 is a cross-sectional view of FIG. 1 cut along the axial direction of a rotating shaft, and FIG. 3 is an embodiment of the present invention. It is the front view which looked at the bearing box main body of the bearing box from the front.

As shown in FIG. 1, the power generation system 1 is disposed between a turbine 2, a compressor 3, a generator (not shown), between the turbine 2 and the compressor 3, and between the turbine 2 and the generator. Bearing housing 4.
The turbine 2 obtains a rotational force by a working fluid (for example, air, high-temperature steam, combustion gas, etc.) flowing inside, and the rotational shaft 5 (see FIG. 2) and the connecting shaft 6 (see FIG. 2) by this rotational force. The compressor 3 and the generator connected via each are driven.

As shown in FIG. 2, the bearing box 4 includes a journal bearing 7 that supports the end of the rotating shaft 5 by bearing, a thrust bearing 8 that supports the center of the connecting shaft 6, and these journal bearing 7 and thrust bearing 8. And a bearing box main body 11 disposed (fixed) on a base (support base: mount) 10 via a base plate 9 and an upper lid 12 covering the upper side of the bearing box main body 11.
The corner portions located at the four corners of the bearing box body 11 protrude (extend) along the axial direction of the rotary shaft 5 from the corner portions located at the four corners of the lower casing body portion 2a of the turbine 2 (see FIG. 1). ) A cat foot part 2b (see FIG. 1) and a cat leg part that protrudes (extends) along the axial direction of the rotary shaft 5 from each corner located at the four corners of the lower casing body part 3a (see FIG. 1) of the compressor 3. A claw footrest 13 (see FIG. 6) for supporting 3b (see FIG. 1) is provided.
In addition, a housing portion 11 a that extends along the axial direction of the rotating shaft 5 and houses the journal bearing 7 and the thrust bearing 8 is provided in the central portion of the bearing box body 11.

  As shown in FIG. 3, the bearing box body 11 has a plurality of (for example, four) reinforcing ribs 14 that connect (couple) the side surfaces of the claw footrest 13 and the bottom plate 11 b of the bearing box body 11. In addition to being provided (fixed), a plurality of sheets (for example, 8 sheets) that connect (couple) each side surface of the housing portion 11a and the claw footrest 13 between the housing portion 11a and the claw footrest 13 Connecting ribs 15 are provided (fixed).

  According to the bearing housing 4 according to the present embodiment, the rigidity of the entire bearing housing body 11 is increased (improved) by the reinforcing ribs 14 newly provided in the bearing housing body 11. The entire box body 11 is deformed into an upwardly protruding bowl shape, the bottom plate 11b of the bearing box body 11 is lifted, the journal bearing 7 and the thrust bearing 8 housed therein are lifted upward, and the rotating shaft 5 And it can prevent that the connection axis | shaft 6 is lifted upwards and a misalignment arises in the rotating shaft 5. FIG.

  Also, by preventing such misalignment of the rotating shaft 5, the rotating part (rotor surface, blade tip, etc.) and the stationary part (casing, blade ring, static) within the turbine casing and the compressor casing. It is possible to prevent increase or decrease in clearance with the inner surface of blades, gas seals, etc., contact, etc., prevent performance degradation of the turbine and compressor, and improve the reliability of the power generation system Can do.

A first reference embodiment of a bearing box according to the present invention will be described with reference to FIG. FIG. 4 is a front view of the bearing housing body of the bearing housing according to the first embodiment of the present invention as seen from the front.
Bearing box 21 according to this embodiment differs from that of the embodiment described above in that it includes a bearing housing body 22 in place of the bearing housing body 11. Because other components are the same as those of the embodiment described above, it is omitted a description of those elements here.

As shown in FIG. 4, the bearing housing body 22 is formed by removing the reinforcing ribs 14 and connecting ribs 15 from the bearing box body 11 described at embodiment (omitted). That is, the bearing housing body 22 in that it does not have a reinforcing rib 14 and the connecting rib 15 is different from the bearing housing body 11 described at embodiment.

According to the bearing box 21 according to the present embodiment, the frictional force generated on the contact surface 13a between the claw foot portions 2b and 3b (see FIG. 1) and the claw foot base 13 due to the difference in thermal expansion (the friction coefficient for the casing weight and the thrust load, respectively). The force of the value obtained by multiplying only the claw footrest 13 is deformed with the lower part (bottom portion) of the claw footrest 13 as a fulcrum. As a result, the bottom plate 11b of the bearing box body 21 is lifted, the journal bearing 7 and the thrust bearing 8 housed therein are lifted upward, and the rotary shaft 5 and the connecting shaft 6 are lifted upward. Thus, it is possible to prevent the alignment deviation from occurring in the rotating shaft 5.
Other operational effects are the same as the embodiment described above, descriptions thereof will be omitted here.

A second reference embodiment of the bearing box according to the present invention will be described with reference to FIG. FIG. 5 is a front view of the bearing box body of the bearing box according to the second embodiment of the present invention as seen from the front.
Bearing box 31 according to this embodiment differs from that of the embodiment described above in that it comprises a fastening means 33 in place of the reinforcing ribs 14. Because other components are the same as those of the embodiment described above, it is omitted a description of those elements here.

  The fastening means 33 is, for example, attached to the central portion of the upper surface of the base plate 9 along the axial direction by a straight T-shaped groove 34, and attached to the central portion of the bottom surface of the bottom plate 11b via a bolt 35. And a T-shaped key 36 which is slidably fitted into the 34.

According to the bearing box 31 according to the present embodiment, the central portion of the base plate 9 and the central portion of the bottom plate 11b are firmly connected (coupled) via the fastening means 33, whereby the bearing Since the rigidity of the entire box body 32 is increased (improved), the entire bearing box body 32 is deformed into a convex bowl shape due to the difference in thermal expansion, and the bottom plate 11b of the bearing box body 32 is lifted. The journal bearing 7 and the thrust bearing 8 accommodated therein are lifted upward, and the rotating shaft 5 and the connecting shaft 6 are lifted upward to prevent the rotational shaft 5 from being misaligned. .
Other operational effects are the same as the embodiment described above, descriptions thereof will be omitted here.

A third reference embodiment of the bearing box according to the present invention will be described with reference to FIG. FIG. 6 is a perspective view showing an outline of a bearing box body of a bearing box according to a third reference embodiment of the present invention.
Bearing box 41 according to this embodiment differs from that of the embodiment described above in that it comprises a frictional force instead (coefficient of friction) reducing means 43 of the reinforcing ribs 14. Because other components are the same as those of the embodiment described above, it is omitted a description of those elements here.

  The frictional force (friction coefficient) reducing means 43 is, for example, a sheet-like member made of tetrafluoroethylene resin (PTFE) having excellent self-lubricity, weather resistance, and low friction characteristics. It is attached (arranged) so as to cover the contact surface 13a.

According to the bearing box 41 according to the present embodiment, the friction coefficient at the contact surface 13a between the claw foot portions 2b and 3b and the claw foot platform 13 can be reduced, and the rotation with the lower part (bottom) of the claw foot platform 13 as a fulcrum. Since the moment can be reduced, the entire bearing box main body 42 is deformed upwardly into a bowl shape due to the difference in thermal expansion, and the bottom plate 11b of the bearing box main body 42 is lifted, and the journal bearing 7 housed therein is accommodated. Further, the thrust bearing 8 is lifted upward, and the rotating shaft 5 and the connecting shaft 6 are lifted upward to prevent the rotational shaft 5 from being misaligned.
Other operational effects are the same as the embodiment described above, descriptions thereof will be omitted here.

A fourth reference embodiment of the bearing box according to the present invention will be described with reference to FIG. FIG. 7 is a front view of the bearing housing body of the bearing housing according to the fourth embodiment of the present invention as seen from the front.
Bearing box 51 according to this embodiment differs from that of the embodiment described above in that it comprises a tension wire 53 in place of the reinforcing ribs 14. Because other components are the same as those of the embodiment described above, it is omitted a description of those elements here.

  The tension wire 53 passes the upper lid 12 in a state where the upper lid 12 is put on the bearing box main body 52, and connects the cat footrest 13 positioned on the left side of the bearing box main body 52 and the cat footrest 13 positioned on the right side. A plurality of (for example, two) wire ropes to be connected (coupled), and each tension wire 53 is bridged in a state where a predetermined tension force is applied.

According to the bearing box 51 according to the present embodiment, the rigidity of the entire bearing box body 52 is increased (improved) by the tension wire 53, so that the entire bearing box body 52 protrudes upward due to the difference in thermal expansion. The bottom plate 11b of the bearing box main body 52 is lifted, the journal bearing 7 and the thrust bearing 8 housed therein are lifted upward, and the rotary shaft 5 and the connecting shaft 6 are lifted upward. As a result, it is possible to prevent misalignment of the rotating shaft 5.
Other operational effects are the same as the embodiment described above, descriptions thereof will be omitted here.

A fifth reference embodiment of the bearing box according to the present invention will be described with reference to FIG. FIG. 8 is a front view of the bearing box body of the bearing box according to the fifth embodiment of the present invention as seen from the front.
Bearing box 61 according to this embodiment differs from that of the embodiment described above in that it comprises a tension wire 63 in place of the reinforcing ribs 14. Because other components are the same as those of the embodiment described above, it is omitted a description of those elements here.

  The tension wire 63 is hung around a pulley 64 disposed below the housing portion 11a (more specifically, inside the base plate 9), and the center of the claw foot base 13 and the bottom plate 11b located on the left side of the bearing box main body 62. A plurality of (for example, four) wire ropes that connect (join) the claw foot 13 and the central portion of the bottom plate 11b, which are located on the right side of the bearing box body 62, and each tension. A predetermined tension force is applied to the wire 63.

According to the bearing box 61 according to the present embodiment, the rigidity of the entire bearing box body 62 is increased (improved) by the tension wire 63 and the pulley 64, and therefore the entire bearing box body 62 is caused by the difference in thermal expansion. It is deformed into an upwardly protruding bowl shape, and the bottom plate 11b of the bearing box main body 62 is lifted. The journal bearing 7 and the thrust bearing 8 accommodated therein are lifted upward, and the rotating shaft 5 and the connecting shaft 6 are It is possible to prevent the rotation axis 5 from being misaligned by being lifted upward.
Other operational effects are the same as the embodiment described above, descriptions thereof will be omitted here.

It should be noted that the present invention is not limited to the above-described embodiment, and can be appropriately modified and changed as necessary without departing from the technical idea of the present invention.
For example, in the third reference embodiment described above, as the frictional force (friction coefficient) reducing means 43, a sheet-like material made of tetrafluoroethylene resin (PTFE) having excellent self-lubricity, weather resistance, and low friction characteristics. Although the member is adopted, the present invention is not limited to this, and any member may be used as long as it reduces the frictional force (friction coefficient) such as a roller bearing.

1 Power Generation System 2 Turbine 3 Compressor 4 Bearing Box 7 Journal Bearing (Bearing)
8 Thrust bearing (bearing)
DESCRIPTION OF SYMBOLS 9 Base plate 10 Base 11 Bearing box main body 11a Accommodating part 11b Bottom plate 12 Upper lid 13 Claw footrest 13a Friction surface 14 Reinforcement rib 15 Connection rib 21 Bearing box 22 Bearing box main body 31 Bearing box 32 Bearing box main body 33 Fastening means 41 Bearing box 42 Bearing Box body 43 Friction coefficient reducing means 51 Bearing box 52 Bearing box body 53 Tension wire 61 Bearing box 62 Bearing box body 63 Tension wire 64 Pulley 100 Bearing box body

Claims (2)

A bearing box having a housing portion that houses a bearing and a bottom plate, and that has a rectangular shape in plan view that is installed on a foundation via a base plate, and an upper lid that covers the top of the bearing box body. There,
A space is formed between the side surface of the claw footrest provided at each of the four corners of the bearing box body and the side surface of the accommodating portion,
A plurality of reinforcing ribs for connecting the side surface of the claw footrest provided at each of the four corners of the bearing box body and the bottom plate are provided, and the side surface of the housing portion, the side surface of the claw footrest , and the bottom plate A bearing box comprising a plurality of connecting ribs that connect the upper surface . A bearing box according to claim 1, a turbomachine having a generator that generates electric power by rotating a compressor or a turbine, and a heat exchanger that performs heat exchange between the working fluid flowing inside. Power generation system characterized by

Images