Fixture for connecting rotors of rotary machine and method of connecting rotors

A fixture for connecting rotors of a rotary machine includes: an axial member provided with a column-like fitting portion which is disposed inside of a first bolt hole and fits the first bolt hole; and a sleeve provided with a cylindrical fitting portion which is disposed inside of a second bolt hole and fits the second bolt hole. The axial member further includes a tapered portion which is formed on an end portion of the column-like fitting portion, and is gradually reduced in diameter from the first bolt hole toward the second bolt hole. The cylindrical fitting portion of the sleeve is formed with a tapered hole which is gradually expanded in diameter from the second bolt hole toward the first bolt hole around an axis of the sleeve.

TECHNICAL FIELD

The present invention relates to a fixture for connecting rotors which is used when connecting divided rotors of a rotary machine. Priority is claimed on Japanese Patent Application No. 2012-174345 filed Aug. 6, 2012, the content of which is incorporated herein by reference.

BACKGROUND ART

A rotor of a rotary machine such as a gas turbine and a steam turbine, for example, is divided into a turbine side and an electric generator side in the axial direction, and the rotor is configured by connecting the divided rotors with each other. One example of such a rotor connection, for example, is disclosed in Patent: Document 1.

When connecting the rotors which are divided in a plural number in this manner, each rotor is suspended by an overhead crane, and an axial alignment between the rotors is performed by operating the crane while each rotor is suspended by the crane. Patent Document 2 is cited as another example of the connection of rotors.

PRIOR ART DOCUMENT

Patent Document

Patent Document 2: Japanese Unexamined Utility Model Application, First Publication No. S61-108521

SUMMARY OF INVENTION

Problem that the Invention is to Solve

Axial alignment of the rotors of a rotary machine which are suspended by the crane is very difficult, and it takes a considerable amount of time to do such an operation. Its workability is not good, and it is likely to become a cause of a cost increase.

An object of the present invention is to provide a fixture for connecting rotors of a rotary machine and a method of connecting rotors which allow easy axial alignment.

Means for Solving the Problem

To solve the above problem, the present invention has adopted the following means.

According to a first aspect of the present invention, there is provided a fixture for connecting rotors of a rotary machine, which is used to connect a first rotor and a second rotor to each other by butting a first flange portion provided on an end portion of the first rotor and a second flange portion provided on an end portion of the second rotor to each other, and then inserting a bolt through a first bolt hole which is formed in the first flange portion to a second bolt hole which is formed in the second flange portion, the fixture including: an axial member provided with as column-like fitting portion which is disposed inside of the first bolt hole, and fits the first bolt hole; and a sleeve provided with a cylindrical fitting portion which is disposed inside of the second bolt hole, and fits the second bolt hole. The axial member further includes as tapered portion which is formed at an end portion of the column-like fitting portion, and is gradually reduced in diameter from the first bolt hole toward the second boll hole. The cylindrical fitting portion of the sleeve is formed with a tapered hole which is gradually expanded in diameter from the second bolt hole toward the first bolt hole around an axis of the sleeve and is capable of fitting the tapered portion.

By using such a fixture for connecting the rotors of the rotary machine, the axial member and the sleeve installed in the first and second bolt holes are caused to approach each other. As a result, the tapered portion fits the tapered hole exactly. In such a state of fitting together, a central axis of the axial member and as central axis of the sleeve coincide. According to this, the axial lines of the first bolt hole and the second bolt hole coincide. Thus, the axial alignment of the first flange portion, and the second flange portion can be performed.

In addition, the axial member may include a tool hole which is formed to be dented in the axial direction around the axis of the axial member from an end portion of the first bolt hole side, and a male screw portion which is formed on an end portion of the tapered portion, and extends from the first bolt hole to the second bolt hole.

By using such a tool hole and a male screw portion, it is possible to fasten the sleeve to the axial member. Since, the tapered portion of the axial member and the tapered hole of the sleeve can he fitted together easily and certainly, the axial alignment of the first flange portion and the second flange portion can be performed. In addition, it is possible to easily detach the axial member and the sleeve.

In addition, a length of the cylindrical fitting portion in an axial direction may be less than or equal to a width of the second flange portion in the direction in which the bolt is inserted.

In this manner, since the cylindrical fitting portion does not protrude from the second flange portion toward the first flange portion when the cylindrical fitting portion fits the second bolt hole, the axial alignment of the first flange portion and the second flange portion is more easily performed.

Further, the axial member may include a first screw hole for installing a drawing tool which is formed to be dented in the axial direction of the axial member from the end portion of the first bolt hole side.

For example, when the drawing tool such as an eyebolt is screwed into the first screw hole, it is possible to easily draw the axial member out from the first bolt hole and the second bolt hole.

In addition, the sleeve may include a second screw hole for installing a drawing tool which is formed to be dented in the axial direction of the sleeve from the end portion of the second bolt hole side.

For example, when the drawing tool such as an eyebolt is screwed into the second screw hole, it is possible to easily draw the sleeve out from the second bolt hole.

According to a second aspect of the present invention, there is provided a method of connecting rotors, which connects a first rotor and a second rotor with each other by butting a first flange portion provided on an end portion of the first rotor and a second flange portion provided on an end portion of the second rotor, then inserting bolts through a plurality of first bolt holes which are formed in the first flange portion and a plurality of second bolt holes which are thrilled in the second flange portion, the method including: a connection preparation step of preparing a fixture for connecting rotors including an axial member provided with a column-like fitting portion which is disposed inside of the first bolt hole and fits the first bolt hole, and a sleeve provided with a cylindrical fitting portion which is disposed inside of the second bolt hole and fits the second bolt hole, in which the axial member is further provided with a tapered portion which is formed at an end portion of the column-like fitting portion, and is gradually reduced in diameter from the first bolt hole toward the second bolt hole, and the cylindrical fitting portion attic sleeve is provided with a tapered hole which is gradually expanded in diameter from the second bolt hole toward the first bolt hole around an axis of the sleeve; a fixture installation step of making the column-like fitting portion of the axial member lit any one of the plurality of the first bolt holes, and then making the tapered portion fit the tapered hole by making the cylindrical fitting portion of the sleeve it the second bolt hole corresponding to the first bolt hole; a bolt installation step of installing a bolt by inserting through any one of the first bolt holes and the second bolt holes, other than the first bolt hole or the second bolt hole in which the axial member and the sleeve are fitted in the fixture installation step; a fixture detaching step of detaching the axial member and the sleeve installed in the fixture installation step after the fixture installation step and the bolt installation step; and a bolt final installation step of installing the bolt by inserting through the first bolt hole and the second bolt hole from which the axial member and the sleeve have been detached in the fixture detaching step.

By such a method of connecting the rotors, it is possible to perform the axial alignment of the first flange portion and the second flange portion by making the tapered portion of the fixture for connecting the rotors fit the tapered hole thereof in the fixture installation step. While performing such an axial alignment, it is possible to install the bolt into all the first bolt holes and the second bolt holes, and to easily connect the first rotor and the second rotor.

Effects of the Invention

According to the fixture for connecting the rotors of the rotary machine and the method for connecting the rotors of the present invention, it is possible to easily perform the axial alignment by using the axial member provided with the tapered portion and the sleeve provided with the tapered hole.

DESCRIPTION OF THE EMBODIMENTS

Hereinafter, a connecting fixture1(a fixture for connecting rotors in a rotary machine) according to an embodiment of the present invention will be described, but first of all, a rotor100to which the connecting fixture1is applied will be described.

The rotor100is used, for example, in the rotary machine such as a gas turbine or a steam turbine, and is a member which transmits a rotatory power.

As shown inFIG. 1andFIGS. 2A and 2B, the rotor100is configured by the first rotor110, and the second rotor120connected to an end portion of the first rotor110. Axial lines of the first rotor110and the second rotor120coincide mutually, and form an axial line O of the rotor100. The rotor100formed of the first rotor110and the second rotor120is rotatable around the axial line O.

Hereinafter, the description will be given based on the following. The first rotor110is disposed in a first direction side D1(in the embodiment, a left side when seeing a paper surface ofFIG. 1from the front) of the axial line O with respect to a connecting portion C (refer toFIG. 7C) between the first rotor110and the second rotor120. In addition, the second rotor120is disposed in a second direction side D2(in the embodiment, a right side when seeing a paper surface ofFIG. 1from the front) of the axial line O with respect to the connecting portion C.

The first rotor110includes a first main body portion111which forms a cylindrical shape, and a first flange portion112which is provided on an end portion of the second direction side D2of the first main body portion111, and forms a disc shape of a larger outer diameter than the first main body portion111. The first flange portion112includes a plurality of first bolt holes113which are arranged circumferentially at intervals at positions radially outward from the outer diameter of the first main body portion111and are formed by passing, through the first flange portion112in a direction along the axial line O.

The second rotor120, similarly, includes a second main body portion121which forms a cylindrical shape, and a second flange portion122which is provided on an end portion of the first direction side D1of the second main body portion121, and forms a disc shape of a larger outer diameter than the second main body portion121. The second flange portion122includes a plurality of second bolt holes123which are arranged circumferentially at intervals at positions radially outward from the outer diameter of the second main body portion121and are formed by passing through the second flange portion122in a direction along the axial line O.

The first flange portion112and the second flange portion122have the same diameter. In addition, the first bolt holes113and the second bolt holes123are formed such that, when the first rotor110and the second rotor120are butted together on a concentric axis, the first bolt holes113and the second bolt holes123are disposed at the same circumferential position. In addition, the first bolt holes113and the second bolt holes123have the same inner diameter of holes.

Next, the connecting fixture1will be described.

As shown inFIG. 3, the connecting fixture1includes an axial member10which fits the first bolt hole113and is disposed from the first bolt hole113to the second bolt hole123, and a sleeve20which fits the second bolt hole123and fits the axial member10from an outer circumferential side.

As shown inFIGS. 4A and 4B, the axial member10forms a pin shape around an axis P1, and includes a head portion11provided at the end portion of the first direction side D1, a stopper portion14provided at the second direction side D2of the head portion11, and a column-like fitting portion13provided at the second direction side D2of the stopper portion14.

In addition, the axial member10includes a tapered portion16formed through a chamfered portion15aat the end portion of the second direction side D2of the column-like fitting portion13, and a male screw portion17formed through a chamfered portion15bat the end portion of the second direction side D2of the tapered portion16.

The head portion11forms a cylindrical shape, and further, includes a hexagonal hole (tool hole)12which is formed to be dented from the first direction side D1toward the second direction side D2around an axis P1. At the center of the inside of the hexagonal hole12, a first screw hole19is formed to be further dented from the first direction side D1toward the second direction side D2around the axis P1. Therefore, a screw (not shown) is capable of being screwed into the first screw hole19.

The stopper portion14forms a disc shape of larger diameter than an inner diameter of the first bolt hole113, and an end surface of the stopper portion14which faces the second direction side D2contacts with the first flange portion112in such a state where the axial member10is installed in the first flange portion112. Thus, it is possible to lock the entire axial member10to the first flange portion112.

The column-like fitting portion13forms a column shape having an outer diameter equal to the inner diameter of the first bolt hole113, and is capable of fitting the first bolt hole113. In addition, the chamfered portion15ais provided at the end portion of the second direction side D2. Further, between a total length L3of the column-like fitting portion13and the chamfered portion15aalong the axis P1, and a width L1of the first flange portion112along an axial line O, a relationship L1≧L3of is established. In a state in which the axial member10is installed at the first flange portion112, the entire column-like fitting portion13and the entire chamfered portion15aare disposed inside of the first bolt hole113. In such a state, the axial member10is unmovable in a radial direction of the first bolt hole113.

The tapered portion16forms a truncated circular cone shape which is formed from the first direction side D1toward the second direction side D2through the chamfered portion15a, and is gradually reduced in outer diameter from the column-like fitting portion13. In addition, the tapered portion16is provided so that, in a state where the stopper portion14contacts with the first flange portion112, at least a part of the tapered portion16is positioned inside of the second bolt hole123.

The male screw portion17is positioned at the end portion of the second direction side D2, and forms a column shape of smaller diameter than the tapered portion16. The male screw portion17is provided with the male screw on an outer circumferential surface of the column shape thereof. In addition, the male screw portion17is provided so that, in a state where the stopper portion14contacts with the first flange portion112, at least a part of the male screw portion17protrudes from the second flange portion122toward the second direction side D2.

Among the width L1of the first flange portion112in the direction of the axis P1, a width L2of the second flange portion122in the direction of the axial line O, the total length L3of the column-like fitting portion13and the chamfered portion15ain the direction of the axis P1, and a total length L4of the tapered portion16and the chamfered portion15bin the direction of the axis P1, a relationship of L1+L2>L3+L4is established.

As shown inFIGS. 5A and 5B, the sleeve20forms a cylindrical shape around an axis P2, and includes a cylindrical fitting portion21which fits the second bolt hole123, and a sleeve stopper portion22provided at the second direction side D2of the cylindrical fitting portion21. In addition, in the sleeve20, a tapered hole23which passes through the cylindrical fitting portion21and the sleeve stopper portion22in the direction of the axis P2is formed.

The cylindrical fitting portion21forms a cylindrical shape, is positioned at the first direction side D1, and has an outer diameter equal to an inner diameter of the second bolt hole123so as to be capable of fitting the second bolt hole123. In addition, between to length L5of the cylindrical fitting portion21in the direction of the axis P2, and the width L2of the second flange portion122in the direction of the axial line O, a relationship of L2≧L5is established. In a state where the sleeve20is installed on the second flange portion122, the entire cylindrical fitting portion21is disposed inside of the second bolt hole123. In such as state, the sleeve20is unmovable in a radial direction of the second bolt hole123.

The sleeve stopper portion22is positioned in the second direction side D2, forms a cylindrical shape of greater diameter than the inner diameter of the second bolt hole123, and in a state where the sleeve20is installed on the second flange portion122, an end surface of the sleeve stopper portion22which faces the first direction side D1contacts with the second flange portion122. Thus, it is possible to lock the entire sleeve20to the second flange portion122.

The tapered hole23is formed by passing through the cylindrical fitting portion21and the sleeve stopper portion22in the direction of the axis P2, and is formed so as to he gradually expanded in diameter from the second direction side D2toward the first direction side D1. The tapered hole23is capable of rightly fitting the tapered portion16of the axial member10from the outer circumferential side in a state where the stopper portion14of the axial member10contacts the first flange portion112, and the sleeve stopper portion22contacts the second flange portion122.

In addition, in the sleeve stopper portion22, a plurality of second screw holes24are arranged circumferentially at internals, and are formed to be dented from the second direction side D2toward the first direction side D1. The screw is capable of being screwed into the second screw hole24.

Next, a procedure of the method of connecting the rotor100by using the connecting fixture1will be described.

As shown inFIGS. 6 and 7Ato7C, the method of connecting the rotor100includes a connection preparation step S1of preparing the connecting fixture1by arranging the first rotor110and the second rotor120to face each other, and a fixture installation step S2of installing the connecting fixture1.

In addition, the method of connecting the rotor100includes a bolt installation step S3of installing to bolt30(refer toFIG. 7C) to the first bolt hole113and the second bolt hole123excluding the positions at which the connecting fixture1has been installed in the fixture installation step S2.

Further, after the fixture installation step S2and the bolt installation step S3, the method of connecting the rotor100includes a fixture detaching step S4of detaching the connecting fixture1, and a bolt final installation step S5of finally installing the bolt30to the first bolt hole113and the second bolt hole123from which the connecting fixture1has been detached.

First, the connection preparation step S1is performed. The first rotor110and the second rotor120are suspended by an overhead crane or the like. In addition, in a state of being suspended, the first rotor110and the second rotor120are butted together and disposed so that the first bolt hole113and the second bolt hole123corresponding thereto face each other. At this time, the axis P1of the first bolt hole113and the axis P2of the second bolt hole123which faces the first bolt hole113are in a state of axial misalignment.

Next, the fixture installation step S2is performed. As shown inFIG. 7A, the stopper portion14is caused to contact with the first flange portion112by fining the axial member10to a predetermined number (for example, four) of the first bolt holes113from the first direction side D1. In addition, the sleeve stopper portion22is caused to contact with the second flange portion122by fitting, from the second direction side D2, the sleeve20to the second bolt hole123corresponding to the first bolt hole113in which the axial member10is arranged. At this time, between the first flange portion112and the second flange portion122, axial misalignment in an amount of d1in the radial direction of the axial line O occurs. Similarly, the axial misalignment in the amount of d1occurs between the axis P1and the axis P2as well.

In such a state, as shown inFIG. 7B, the amount of axial misalignment is reduced from d1to d2by bringing the first flange portion112and the second flange portion122closer to each other.

Thus, as shown inFIG. 7C, a nut31ais screwed and fastened to the male screw portion17in a state where the male screw portion17of the axial member10protrudes from the sleeve20toward the second direction side. In addition, the tapered portion16of the axial member10is caused to fit the tapered hole23of the sleeve20, and therewith, the first flange portion112and the second flange portion122are sandwiched between the stopper portion14of the axial member to and nut31a.

Further, the bolt installation step53is performed. As shown inFIG. 7C, the bolt30is inserted, from the first bolt hole113through the second bolt hole123, to a predetermined number (for example, four) of the first bolt holes113and the second bolt holes123excluding the positions at which the axial member10and the sleeve20are installed in the fixture installation step S2. In addition, the first flange portion112and the second flange portion122are sandwiched and connected to each other by screwing and fastening the nuts31bto the bolt30.

At this time, in the bolt installation step S3, the bolt30is installed to only the first bolt hole113and the second bolt hole123corresponding thereto axial centers of which have been caused to coincide by the fixture installation step S2in a case where there are no coinciding axial centers of the first bolt holes113and the second bolt holes123, the connecting fixture1is added by performing the fixture installation step S2again. The fixture installation step S2and the bolt installation step S3are repeated in parallel, and finally, the bolt30or the connecting fixture1is installed to all of the first bolt holes113and the second bolt holes123.

The bolt30is a reamer bolt, but the bolt30is not limited to the reamer bolt and a normal bolt may also be used.

Next, the fixture detaching step S4is performed. In the bolt installation step S3, in a state where the nut31bis fastened to the bolt30, the connecting fixture1is detached by drawing the nut31afrom the axial member10.

Finally, the bolt final installation step S5is performed. The bolt30is installed by inserting through the first bolt hole113and the second bolt hole123from which the connecting fixture1has been detached in the fixture detaching step S4, and the first flange portion112and the second flange portion122are sandwiched to be connected together by the nuts31b.

By using such connecting fixture1, when the connecting fixture1is installed and the tapered portion16is caused to rightly fit the tapered hole23in the fixture installation step S2, the amounts of axial misalignment d1and d2become 0, and the axis P1of the axial member10and the axis P2of the sleeve20are positioned on the same axis. Thus, the axial lines of the fast bolt hole113and the second bolt hole123coincide.

Thus, a fitting of the tapered portion16of the axial member10and the tapered hole23of the sleeve20, and an installation of the bolt30are performed by using all the first bolt holes113and the second bolt holes123. Accordingly, in all the first bolt holes113and the second bolt holes123corresponding thereto, it is possible to make the axial centers coincide. Thus, the axial alignment of the first flange portion112and the second flange portion122can be performed.

In addition, after the bolt final installation step S5has been finished, and the bolt30has been installed to all the first bolt holes113and the second bolt holes123, finally, the axial member10and the sleeve20are all detached. For this reason, at the time of operating the rotor100, they do not remain in the rotor100.

Further, by the hexagonal hole12and the male screw portion17in the axial member10, it is possible to fasten the nut31ato the male screw portion17by inserting a hexagonal wrench to the hexagonal hole12. For this reason, the axial member10and the sleeve20are firmly fastened, and it is possible to cause the tapered portion16of the axial member10and the tapered hole23of the sleeve20to fit easily and firmly.

In addition, it becomes easy to detach the nut31aby the hexagonal hole12. For this reason, it is possible to easily detach the axial member10and the sleeve20.

In addition, by screwing, for example, the eyebolt and the like (not shown) to the first screw hole19of the axial member10, it becomes possible to easily detach the axial member10from the first bolt hole113. Similarly, by screwing the eyebolt and the like (not shown) to the second screw hole24, it becomes possible to easily detach the sleeve20from the second bolt hole123.

By using the connecting fixture1of the embodiment, it is possible to connect the first rotor110and the second rotor120easily.

In addition, the rotor100is not used with the connecting fixture1remaining in the rotor100, as great strength is not necessary, and since the connecting fixture1can be repeatedly used, great cost advantages can be expected.

As mentioned above, a detailed description has been made regarding the embodiment of the present invention, but within a range which does not deviate from the technical idea of the present invention, it is possible to change the design to a certain degree.

For example, it is not always necessary to form the hexagonal hole12and the male screw portion17in the axial member10, and the tapered portion16may be caused to fit the tapered hole23by hitting the axial member10and the sleeve20into the first bolt hole113and the second bolt hole123. In such a case, it is possible to reduce the cost of the axial member10.

Similarly, it is not always necessary to form the first screw hole19of the axial member10, and the second screw hole24of the sleeve20, and a formation position and a quantity, and the like are also not limited to the cases of the above-described embodiments.

In addition, as long as there is no problem of processibility with the axial member10, it is not always necessary to form the chamfered portions15aand15b. The tapered portion16and the column-like fitting portion13, and the tapered portion16and the male screw portion17may be formed to be smoothly continued on the outer circumferential surface.

Further, an installation direction of the axial member10and the sleeve20may be reversed. It is possible to install the axial member10from a second bolt hole123side, and the sleeve20from a first bolt hole113side. In this case, the aforementioned lengths of L1, L2, L3, L4, and L5need to be similarly considered.

In addition, in the aforementioned embodiments, the first rotor110is directly connected with the second rotor120. However, it is possible to use the connecting fixture1even when connecting the first rotor110and the second rotor120, for example, by inserting a connection shaft between the first rotor110and the second rotor120.

By the fixture for connecting the rotors of the rotary machine, and the method of connecting the rotors, it becomes possible to easily perform the axial alignment by using the axial member provided with the tapered portion and the sleeve provided with the tapered hole.

DESCRIPTION OF NUMBERS AND NUMERALS

1connecting fixture (fixture for connecting rotors of rotary machine)

111first main body portion

121second main body portion

D1first direction side

D2second direction side

O axial line

S1connection preparation step

S2fixture installation step

S3bolt installation step

S5bolt final installation step