JP2018150941A - Steam turbine system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To suppress unbalancing of a load applied to a bearing device rotatably supporting a rotor in a steam turbine.SOLUTION: A steam turbine system includes a steam turbine, a steam valve and a control device 50. Four nozzle chambers 22 arranged in a circumferential direction on an axis Ar as a center, are formed in a casing of the steam turbine as a nozzle chamber into which steam flows. The first nozzle chamber 22A and the fourth nozzle chamber 22D among four nozzle chambers 22 are disposed at an upper side with respect to the axis, the second nozzle chamber 22B and the third nozzle chamber 22c are disposed at a lower side with respect to the axis, further the first nozzle chamber 22A and the second nozzle chamber 22 B are disposed at one side of the axis in a lateral direction, and the third nozzle chamber 22c and the fourth nozzle chamber 22D are disposed at the other side of the axis in the lateral direction. The control device 50 outputs valve opening commands indicating valve openings to a third steam valve 47C and a fourth steam valve 47D, and outputs valve opening commands indicating large valve openings to a first steam valve 47A and a second steam valve 47B.SELECTED DRAWING: Figure 2

Description

  The present invention relates to steam turbine equipment.

  Some steam turbines are provided with a plurality of nozzle chambers as nozzle chambers into which steam flows. Such a steam turbine is connected to a steam control valve for adjusting the amount of steam flowing into the nozzle chamber for each of the plurality of nozzle chambers.

  Patent Document 1 below discloses a method for reducing a load applied to a rotor of a steam turbine in an operation test of a steam control valve for each of a plurality of nozzle chambers.

  In the casing of this steam turbine, four nozzle chambers arranged in the circumferential direction are formed around the axis that is the rotation center of the rotor. A steam pipe is connected to each of the four nozzle chambers, and a steam control valve is provided in the steam pipe. Here, of the four nozzle chambers, one nozzle chamber is defined as a first nozzle chamber, a nozzle chamber adjacent to the first nozzle chamber in the circumferential direction is defined as a second nozzle chamber, and the second nozzle chamber is defined in the circumferential direction. An adjacent nozzle chamber is defined as a third nozzle chamber, and a nozzle chamber adjacent to the third nozzle chamber in the circumferential direction is defined as a fourth nozzle chamber. In addition, a steam control valve that adjusts the amount of steam flowing into the first nozzle chamber is a first steam control valve, and a steam control valve that controls the amount of steam flowing into the second nozzle chamber is a second steam control valve. A steam control valve that adjusts the amount of steam flowing into the nozzle chamber is a third steam control valve, and a steam control valve that adjusts the amount of steam flowing into the fourth nozzle chamber is a fourth steam control valve.

  If the first steam control valve is closed when testing the first steam control valve, steam will flow into the second nozzle chamber and the fourth nozzle chamber when the first steam control valve is closed. The steam does not flow into the first nozzle chamber and the third nozzle chamber. That is, the steam flows into two nozzle chambers facing each other with the axis as a reference, and the steam does not flow into the other two nozzle chambers facing each other with the axis as a reference. In this case, the rotor blades are alternately generated twice when the force received from the steam is large and small while the rotor rotates once. For this reason, the rotor receives a shock twice during one rotation, that is, a double shock. When the rotor receives a double shock, after the first shock, the second shock is received before the shock is attenuated, and the fatigue of the rotor proceeds.

  Therefore, in Patent Document 1, a first steam pipe that connects the first steam control valve and the first nozzle chamber and a second steam pipe that connects the second steam control valve and the second nozzle chamber are connected by a connecting pipe. And connecting a third steam pipe connecting the third steam control valve and the third nozzle chamber and a fourth steam pipe connecting the fourth steam control valve and the fourth nozzle chamber with a connecting pipe. Yes. As a result, when testing the first steam control valve, even if the third steam control valve is closed, the steam that has passed through the fourth steam control valve enters the third nozzle chamber via the connecting pipe and the third steam pipe. Since steam flows in, double shock can be prevented.

JP 62-168906 A

  An object of this invention is to provide the steam turbine equipment which suppresses that the load concerning the bearing apparatus which supports a rotor rotatably is an unbalanced load.

Steam turbine equipment as one aspect according to the present invention,
A rotor that rotates about an axis; a steam turbine having a casing that rotatably covers the rotor; a steam valve that adjusts an amount of steam flowing into the steam turbine; and a control device that controls the steam valve. . In the casing, four nozzle chambers arranged in the circumferential direction around the axis are formed as nozzle chambers into which steam flows. Of the four nozzle chambers, the first nozzle chamber and the fourth nozzle chamber are disposed above the axis, the second nozzle chamber and the third nozzle chamber are disposed below the axis, and the The first nozzle chamber and the second nozzle chamber are disposed on one side in a lateral direction perpendicular to the axis from the axis, and the third nozzle chamber and the fourth nozzle chamber are in the lateral direction from the axis. It is arrange | positioned at the other side. As the steam valve, a first steam valve for adjusting the amount of steam flowing into the first nozzle chamber, a second steam valve for adjusting the amount of steam flowing into the second nozzle chamber, and an inflow into the third nozzle chamber A third steam valve for adjusting the amount of steam; and a fourth steam valve for adjusting the amount of steam flowing into the fourth nozzle chamber. The control device outputs a valve opening command indicating a valve opening degree to the third steam valve and the fourth steam valve when the output of the steam turbine is set to a predetermined output less than a rated output. , A valve opening command indicating a valve opening larger than the valve opening of the third steam valve and the valve opening of the fourth steam valve is output to the first steam valve and the second steam valve. To do. The rotor is configured to rotate to the other side in the lateral direction above the axis.

  In the said steam turbine equipment, when making the output of the said steam turbine into the predetermined output less than a rated output, it can suppress that the load concerning the bearing apparatus which supports a rotor rotatably becomes an unbalanced load.

  Here, in the steam turbine equipment, the first steam valve and the third steam valve are arranged on the one side in the lateral direction from the axis, and the second steam valve and the fourth steam valve are You may arrange | position on the said other side of the said horizontal direction rather than the said axis line.

  In any of the above steam turbine facilities, the steam turbine includes a bearing device that rotatably supports the rotor, and the bearing device is arranged in a circumferential direction around the axis and the rotor. A plurality of bearing pads arranged along the outer peripheral surface of the bearing pad and a pad support that supports the bearing pad so as to be slidable from the radial side with respect to the axis.

  In the steam turbine equipment, since the plurality of bearing pads are supported so as to be capable of sliding, the occurrence of the oil whip phenomenon in the bearing device can be suppressed.

  According to one aspect of the present invention, it is possible to suppress the load applied to the bearing device that rotatably supports the rotor from becoming an uneven load.

It is explanatory drawing which shows the structure of the steam turbine installation in one Embodiment which concerns on this invention. It is explanatory drawing which shows the steam inflow system | strain to the steam turbine in one Embodiment which concerns on this invention. It is sectional drawing of the bearing apparatus in one Embodiment which concerns on this invention. It is a graph which shows the valve opening degree change of each steam control valve in the starting process in one Embodiment which concerns on this invention. It is explanatory drawing which shows the state of each steam control valve in the process of performing the valve test of each steam control valve in one Embodiment which concerns on this invention. It is explanatory drawing which shows the inflow vapor | steam amount to each nozzle chamber in the process of performing the valve test of each steam control valve in one Embodiment which concerns on this invention. FIG. 4A is an explanatory diagram showing the amount of steam flowing into each nozzle chamber at the time of low output in the comparative example, and FIG. 4B shows the load applied to the bearing device at the time of low output in the comparative example. It is explanatory drawing which shows. The figure (a) is explanatory drawing which shows the inflow vapor | steam amount to each nozzle chamber at the time of the low output in one Embodiment which concerns on this invention, The figure (b) is in one Embodiment which concerns on this invention. It is explanatory drawing which shows the load concerning the bearing apparatus at the time of low output. It is explanatory drawing which shows the steam inflow system | strain to the steam turbine in another comparative example.

  Hereinafter, an embodiment of a steam turbine facility according to the present invention will be described in detail with reference to the drawings.

  As shown in FIG. 1, the steam turbine equipment of the present embodiment includes a steam turbine 10, a steam pipe 40 through which steam supplied to the steam turbine 10 flows, a steam stop valve 46, a steam control valve 47, and a steam stop valve. 46 and a control device 50 for controlling the operation of the steam control valve 47.

  The steam turbine 10 includes a rotor 11 that rotates about an axis Ar, and a casing 21 that covers the rotor 11 rotatably. For the convenience of the following description, the direction in which the axis Ar extends is the axial direction Da, the direction perpendicular to the axis Ar and the horizontal direction is the horizontal direction Dh (see FIG. 2), and the diameter is based on the axis Ar. The direction is simply the radial direction Dr, and the circumferential direction around the axis Ar is simply the circumferential direction Dc. One side of the axial direction Da is the upstream side, and the other side of the axial direction Da is the downstream side.

  The rotor 11 includes a rotor shaft 12 that extends in the axial direction Da around the axis line Ar, and a plurality of blade stages 13 that are attached to the outer periphery of the rotor shaft 12. The plurality of blade stages 13 are arranged in the axial direction Da. One blade stage 13 has a plurality of blades 14 arranged in the circumferential direction Dc.

  The casing 21 includes a nozzle chamber 22 into which steam from the outside flows, a steam main channel chamber 23 through which steam from the nozzle chamber 22 flows, and an exhaust chamber 24 through which the steam flowing from the steam main channel chamber 23 is discharged. Is formed. The nozzle chamber 22 is formed on the upstream side of the most upstream blade stage 13 a among the plurality of blade stages 13. The steam main flow path chamber 23 is an annular space formed on the outer peripheral side of the rotor shaft 12 and in a region where a plurality of blade stages 13 exist in the axial direction Da. The exhaust chamber 24 is formed downstream of the main steam channel chamber 23, in other words, downstream of the most downstream blade stage 13 d among the plurality of blade stages 13.

  A speed-regulating stage nozzle 25 a is provided in the nozzle chamber 22 and at the boundary with the steam main flow path chamber 23. The speed control nozzle 25a has a plurality of speed control vanes 26a arranged in the circumferential direction Dc (see FIG. 2). Among the plurality of blade stages 13, the most upstream blade stage 13 forms a speed-control blade stage 13a facing the speed-control nozzle 25a in the axial direction Da. Among the plurality of blade stages 13, the blade stage 13 adjacent to the downstream side of the speed-control blade stage 13a forms the first blade stage 13b and is adjacent to the downstream side of the first blade stage 13b. The moving blade stage 13 is the second moving blade stage 13c and the most downstream moving blade stage 13 is the final moving blade stage 13d.

  A stationary blade stage 25 is disposed in the steam main channel chamber 23 and upstream of each blade stage 13 from the first blade stage 13b to the final blade stage 13d. The plurality of stationary blade stages 25 are all attached to the inner peripheral side of the casing 21. One stationary blade stage 25 has a plurality of stationary blades 26 arranged in the circumferential direction Dc.

  A seal device 29 that seals between the inner peripheral side of the casing 21 and the outer peripheral side of the rotor shaft 12 is provided at the end of the casing 21 in the axial direction Da. Both end portions of the rotor 11 in the axial direction Da are supported by the bearing device 30.

  As shown in FIG. 3, the bearing device 30 includes four bearing pads 31 arranged in the circumferential direction Dc on the outer peripheral side of the rotor shaft 12, a pad support 32 that supports the bearing pad 31, a bearing pad 31, and a pad support. And a bearing case 33 covering 32. The bearing pad 31 has an arc shape. The radius of the inner peripheral surface 31 i of the bearing pad 31 is larger than the radius of the rotor shaft 12 at the position where the bearing pad 31 is disposed in the rotor shaft 12. An intermediate portion in the circumferential direction Dc of the bearing pad 31 on the outer peripheral surface 31 o of the bearing pad 31 is in contact with the pad support 32. The pad support 32 is fixed to the inner peripheral surface of a cylindrical bearing case 33. Since the bearing pad 31 is supported by the pad support 32 as described above, the bearing pad 31 can swing around the contact position with the pad support 32 in a virtual plane perpendicular to the axis Ar. Furthermore, the bearing pad 31 can swing around the contact position with the pad support 32 in a virtual plane including the contact position with the pad support 32 and the axis Ar.

  When rotating the rotor 11, oil is present between the inner peripheral surface 31 i of each bearing pad 31 and the outer peripheral surface of the rotor shaft 12. In plain bearings, the oil whip phenomenon can be a problem. This oil whip phenomenon is the unstable vibration generated in the oil due to the unbalance of the mass of the rotating shaft, the assembly tolerance of the bearing device with respect to the rotating shaft, and the like. In the present embodiment, the occurrence of this oil whip phenomenon is suppressed by using a bearing device 30 having a sliding bearing pad 31, that is, a tilting bearing device.

  As shown in FIG. 2, four nozzle chambers 22 are formed in the casing 21 of the present embodiment. The four nozzle chambers 22 are arranged in the circumferential direction Dc around the axis line Ar. Here, one nozzle chamber 22 of the four nozzle chambers 22 is defined as a first nozzle chamber 22A, and on the side opposite to the rotation direction R of the rotor 11 in the circumferential direction Dc with respect to the first nozzle chamber 22A. The nozzle chamber 22 adjacent to a certain rotation opposite side Rc is defined as a second nozzle chamber 22B. Furthermore, the nozzle chamber 22 adjacent to the rotation opposite side Rc in the circumferential direction Dc with respect to the second nozzle chamber 22B is defined as a third nozzle chamber 22C, and the rotation in the circumferential direction Dc with respect to the third nozzle chamber 22C. The nozzle chamber 22 adjacent to the opposite side Rc is defined as a fourth nozzle chamber 22D. That is, in the present embodiment, the four nozzle chambers 22 are arranged in the first nozzle chamber 22A, the second nozzle chamber 22B, the third nozzle chamber 22C, and the fourth nozzle chamber 22D toward the rotation opposite side Rc in the circumferential direction Dc. They are in order.

  The first nozzle chamber 22A and the fourth nozzle chamber 22D are disposed above the axis line Ar, and the second nozzle chamber 22B and the third nozzle chamber 22C are disposed below the axis line Ar. The first nozzle chamber 22A and the second nozzle chamber 22B are arranged on one side in the horizontal direction Dh with respect to the axis Ar, and the third nozzle chamber 22C and the fourth nozzle chamber 22D are on the other side in the horizontal direction Dh with respect to the axis Ar. Arranged on the side.

  The steam pipe 40 is connected to a steam main pipe 41 through which steam from a steam supply source such as a boiler flows, two steam branch pipes 42a and 42b connected to the steam main pipe 41, and steam branch pipes 42a and 42b. And four nozzle chamber steam pipes 43a, 43b, 43c, 43d. That is, in the steam pipe 40 of the present embodiment, the steam main pipe 41 branches into two, one of which forms the first steam branch pipe 42a and the other of which forms the second steam branch pipe 42b. Further, the first steam branch pipe 42a branches into two, one of which forms the first nozzle chamber steam pipe 43a, the other of which forms the third nozzle chamber steam pipe 43c, and the second steam branch pipe 42b of 2 One of the two branches forms a second nozzle chamber steam pipe 43b, and the other forms a fourth nozzle chamber branch pipe 42d.

  Of the four nozzle chamber steam pipes 43a, 43b, 43c, 43d, the first nozzle chamber steam pipe 43a is connected to the first nozzle chamber 22A. The second nozzle chamber steam pipe 43b is connected to the second nozzle chamber 22B, the third nozzle chamber steam pipe 43c is connected to the third nozzle chamber 22C, and the fourth nozzle chamber steam pipe 43d is connected to the fourth nozzle chamber 22D. ing.

  A steam stop valve 46 and a steam control valve 47 are provided in each of the four nozzle chamber steam pipes 43a, 43b, 43c, and 43d.

  Similarly to the first nozzle chamber 22A, the first steam stop valve 46A and the first steam control valve 47A provided in the first nozzle chamber steam pipe 43a are arranged on one side in the horizontal direction Dh with respect to the axis Ar. Has been. Unlike the second nozzle chamber 22B, the second steam stop valve 46B and the second steam control valve 47B provided in the second nozzle chamber steam pipe 43b are arranged on the other side in the horizontal direction Dh with respect to the axis Ar. Yes. Unlike the third nozzle chamber 22C, the third steam stop valve 46C and the third steam control valve 47C provided in the third nozzle chamber steam pipe 43c are arranged on one side in the lateral direction Dh with respect to the axis Ar. Yes. The fourth steam stop valve 46D and the fourth steam control valve 47D provided in the fourth nozzle chamber steam pipe 43d are arranged on the other side in the horizontal direction Dh with respect to the axis Ar, similarly to the fourth nozzle chamber 22D. ing.

  Each of the steam stop valves 46 and each of the steam control valves 47 operates according to commands from the control device 50. The control device 50 accepts various instructions, various detection data, and the like, and controls each steam stop valve 46 and each steam control valve 47 based on the various instructions, various detection data, etc. received by the reception unit 51. And a command output unit 52 for outputting a valve opening command.

  Next, the operation of the steam turbine equipment described above and the test method for each valve will be described.

  When the receiving unit 51 of the control device 50 receives an instruction to start the steam turbine from a higher-level device or the like, for example, a valve opening command indicating a valve opening according to a predetermined opening-time opening pattern is sent to each steam stop. It outputs to the valve 46 and each steam control valve 47. In addition, you may determine the opening degree of each steam stop valve 46 and each steam control valve 47 at the time of starting according to the temperature of the steam which passes the inside of the steam main pipe 41, for example.

  FIG. 4 shows the opening degree opening pattern of each steam control valve 47. In FIG. 4, the horizontal axis represents the steam turbine output (%), and the vertical axis represents the valve opening (%). The steam turbine output (%) is the ratio of the actual output (MW) of the steam turbine 10 to the rated output (MW) of the steam turbine 10 at that time. Each steam stop valve 46 is opened before the corresponding steam control valve 47 begins to open.

  The command output unit 52 of the control device 50 indicates that the valve opening degree is gradually opened with respect to the first steam control valve 47A and the second steam control valve 47B when the reception unit 51 receives an instruction to start the steam turbine. Outputs the valve opening command. When the first steam control valve 47A and the second steam control valve 47B are substantially 50% open, the command output unit 52 of the control device 50 gradually increases the valve opening with respect to the third steam control valve 47C. A valve opening command indicating that the valve is opened is output.

  The command output unit 52 of the control device 50 outputs a valve opening command indicating that the valve opening is gradually opened to the first steam control valve 47A, the second steam control valve 47B, and the third steam control valve 47C. In the process, when the valve opening of the first steam control valve 47A and the second steam control valve 47B is approximately 75% and the valve opening of the third steam control valve 47C is approximately 25%, A valve opening command indicating that the valve opening is gradually opened is also output to the steam control valve 47D.

  In this embodiment, the first steam control valve 47A and the second steam control valve 47B have valve openings of 100%, the third steam control valve 47C has a valve opening of 50%, and the fourth steam control valve 47B. When the valve opening of 47D becomes 10%, the steam turbine output becomes 100%, in other words, the rated output.

  After the steam turbine output reaches the rated output, in the present embodiment, basically, for example, only the valve opening degree of the third steam control valve 47C is changed to cope with load fluctuations. For this reason, in this embodiment, when the steam turbine output is lower than the rated output, basically, the first steam control valve 47A and the second steam control valve 47B are fully opened (opening degree 100%), and the third steam control valve. 47C and the fourth steam control valve 47D are slightly opened.

  By the way, as shown in FIG. 7, the four nozzle chambers 28 in the comparative example are arranged in the first nozzle chamber 28A and the second nozzle chamber 28B toward the rotor rotation side Rr that is the rotation direction side of the rotor in the circumferential direction Dc. Assume that the fourth nozzle chamber 28D and the third nozzle chamber 28C are arranged in this order. Furthermore, it is assumed that the first nozzle chamber 28A and the second nozzle chamber 28B are disposed below the axis Ar, and the third nozzle chamber 28C and the fourth nozzle chamber 28D are disposed above the axis Ar. The second nozzle chamber 28B and the fourth nozzle chamber 28D are arranged on one side in the horizontal direction Dh with respect to the axis Ar, and the first nozzle chamber 28A and the third nozzle chamber 28C are on the other side in the horizontal direction Dh with respect to the axis Ar. Is arranged.

  In this comparative example, the steam turbine output is lower than the rated output, including when the steam turbine is started, the first steam control valve 47A and the second steam control valve 47B are fully opened (opening degree 100%), and the third steam control valve. When the 47C and the fourth steam control valve 47D are slightly opened or fully closed, the first nozzle chamber 28A and the second nozzle chamber 28B disposed below the axis Ar have a large flow rate of steam. Is supplied, and almost no steam is supplied to the third nozzle chamber 28C and the fourth nozzle chamber 28D disposed above the axis Ar.

  As described above, when the rotor 11 is rotated by steam substantially from only the lower half nozzle chambers 28A and 28B, the rotor 11 has a steam force Fc directed toward the rotor rotation side Rr at a position directly below the axis Ar. Acts as a force for rotating the rotor 11. In addition to the steam force Fc, gravity W acts on the rotor 11 vertically downward. Therefore, the rotor 11 is subjected to a diagonally downward force C directed toward one side of the lateral direction Dh while being directed downward as a resultant force of the steam force Fc and the gravity W.

  Therefore, in the comparative example, when the steam turbine output is lower than the rated output, of the four bearing pads 31 of the bearing device 30 that rotatably supports the rotor 11, the bearing is positioned obliquely downward with respect to the axis Ar. The pad 31 a receives most of the force C applied to the rotor 11. That is, an eccentric load is applied to the bearing device 30. As a result, only the metal temperature of one of the four bearing pads 31 is increased, and the bearing pad 31 a is worn faster than the other bearing pads 31. Further, when one of the four bearing pads 31 is worn earlier than the other bearing pads 31, vibration of the rotor 11 is also caused.

  On the other hand, in this embodiment, the steam turbine output is lower than the rated output, including when the steam turbine 10 is started, and the first steam control valve 47A and the second steam control valve 47B are fully opened (opening degree 100%). When the steam control valve 47C and the fourth steam control valve 47D are slightly opened or fully closed, the first nozzle chamber 22A and the second nozzle chamber 22B disposed on one side in the lateral direction Dh with respect to the axis Ar. A large amount of steam is supplied, and almost no steam is supplied to the third nozzle chamber 22C and the fourth nozzle chamber 22D arranged on the other side in the lateral direction Dh from the axis Ar.

  As described above, when the rotor 11 is rotated by the steam substantially only from the lateral half nozzle chambers 22A and 22B, the rotor 11 has a steam force F directed toward the rotor rotation side Rr at a position directly beside the axis Ar. Acts as a force for rotating the rotor 11. In addition to the steam force F, gravity W acts on the rotor 11 vertically downward. Therefore, the steam force F and the gravity W cancel each other on the rotor 11, and a force C smaller than the steam force and gravity acts in the vertical direction as the resultant force.

  Therefore, in the present embodiment, it is possible to suppress a great load from being applied to the specific bearing pad 31 among the four bearing pads 31. That is, in this embodiment, it can suppress that the load concerning the bearing apparatus 30 turns into an eccentric load. As a result, the life of each bearing pad 31 can be averaged, the life of each bearing pad 31 can be lengthened, and vibration of the rotor 11 due to uneven wear of the bearing device 30 can also be suppressed.

  Another comparative example will be considered. In this comparative example, as shown in FIG. 9, the first nozzle chamber 22A and the first steam control valve 47A are both arranged on one side in the lateral direction Dh with respect to the axis Ar, and the second nozzle chamber 22B and the first The two-steam control valve 47B is also disposed on one side in the lateral direction Dh with respect to the axis Ar.

  In this comparative example, the steam turbine output is lower than the rated output, the first steam control valve 47A and the second steam control valve 47B are fully opened (opening degree 100%), the third steam control valve 47C and the fourth steam control valve 47D. Is slightly opened or fully closed, one of the two steam branch pipes 42a and 42b connected to the steam main pipe 41 is disposed on one side in the horizontal direction Dh, and the first steam control valve 47A and A large amount of steam flows through the first steam branch pipe 42a that supplies steam to the second steam control valve 47B and is disposed on the other side in the lateral direction Dh, and is supplied to the third steam control valve 47C and the fourth steam control valve 47D. Almost no steam flows through the second steam branch pipe 42b for supplying steam.

  In this way, when there is a steam pipe 42b where the steam hardly flows and the steam stays, drain accumulates in the steam pipe 42b, and when a large amount of steam flows through the steam pipe 42b, This drain flows into the steam turbine 10 and causes damage to the moving blades and stationary blades.

  Therefore, in the present embodiment, as described above with reference to FIG. 2, the first nozzle chamber 22A and the first steam control valve 47A are both disposed on one side in the lateral direction Dh with respect to the axis Ar, and the second nozzle Although the chamber 22B is disposed on one side in the lateral direction Dh with respect to the axis Ar, the second steam control valve 47B is disposed on the other side in the lateral direction Dh with respect to the axis Ar.

  Therefore, in the present embodiment, the steam turbine output is lower than the rated output, the first steam control valve 47A and the second steam control valve 47B are fully opened (opening degree 100%), and the third steam control valve 47C and the fourth steam. Of the two steam branch pipes 42a and 42b connected to the steam main pipe 41, the first steam is disposed on one side in the lateral direction Dh even when the control valve 47D is slightly opened or fully closed. Compared with both the first steam branch pipe 42a that supplies steam to the control valve 47A and the second steam branch pipe 42b that is disposed on the other side in the lateral direction Dh and supplies steam to the second steam control valve 47B. A large amount of steam flows. Therefore, in the present embodiment, it is possible to prevent the steam drain from accumulating in one of the two steam branch pipes 42a and 42b.

  As described above, in the present embodiment, from the viewpoint of extending the life of the bearing device 30, reducing vibration of the rotor 11, and suppressing drainage in the steam pipe 40, the four nozzle chambers 22, the four steam control valves 47, The arrangement of the steam stop valve 46 is as shown in FIG.

  However, as a result of the arrangement of the four nozzle chambers 22, the four steam control valves 47, and the four steam stop valves 46 shown in FIG. 2, in the present embodiment, in order to suppress a double shock during the valve test, It is difficult to connect the one nozzle chamber steam pipe 43a and the second nozzle chamber steam pipe 43b with a connecting pipe.

  Therefore, in this embodiment, a valve operation is performed to suppress double shock during a valve test without providing a connecting pipe.

  In the valve test of the present embodiment, for example, when the steam turbine 10 has a rated output, the first steam control valve 47A, the second steam control valve 47B, the third steam control valve 47C, and the fourth steam control valve 47D are arranged in this order. Test these valves. In this valve test, after the valve opening command indicating the fully closed state is output from the control device 50 to the valve to be tested, it is confirmed whether or not the valve to be tested is actually fully closed. .

  When the steam turbine 10 has a rated output, as described above with reference to FIG. 4, the first steam control valve 47A and the second steam control valve 47B are fully opened (valve opening degree 100%), and the third steam control valve 47C The valve opening degree is 50%, and the valve opening degree of the fourth steam control valve 47D is 10%. Here, as shown in FIGS. 5 and 6, the state of the four steam control valves 47 when the steam turbine 10 is at the rated output is set to the 0th state. In FIG. 6, the area of the white region in the nozzle chamber 22 indicates the flow rate of the steam flowing into the nozzle chamber 22.

  When testing the first steam control valve 47A, the first steam control valve 47A and the second steam control valve 47B are fully open. On the other hand, the valve opening degree of the third steam control valve 47C and the fourth steam control valve 47D is set to 25% (first state). In the transition process from the 0th state to the 1st state, the command output unit 52 of the control device 50 outputs a valve opening degree adjustment command to the third steam control valve 47C and the fourth steam control valve 47D, and the third steam An opening degree aligning step for aligning the valve opening degree of the adjusting valve 47C and the valve opening degree of the fourth steam adjusting valve 47D is executed. Before and after the opening degree adjusting process, the third steam control valve 47C is slightly closed so that the flow rate of the steam flowing into the steam turbine 10 does not substantially change, and the third steam control valve 47C is opened. The degree is changed from 50% to 25%, the fourth steam control valve 47D is slightly opened, and the valve opening degree of the fourth steam control valve 47D is changed from 10% to 25%. In the present embodiment, the fact that the flow rate of the steam flowing into the steam turbine 10 does not substantially change means that the variation of the steam flow rate is within 10%.

  Next, a target valve fully closing process for fully closing the first steam control valve 47A, which is a test target, is performed while the second steam control valve 47B is fully opened. At this time, the command output unit 52 of the control device 50 outputs a test opening command indicating full closure to the first steam control valve 47A. Further, the command output unit 52 of the control device 50 outputs a non-target valve opening degree change command to the third steam control valve 47C and the fourth steam control valve 47D, and synchronizes with the target valve fully closing process, An opening degree synchronization changing step is performed in which the valve openings of the third steam control valve 47C and the fourth steam control valve 47D are set to 75%.

  In the opening degree synchronization changing step, the opening operation of the third steam control valve 47C and the fourth steam control valve 47D is started in accordance with the timing at which the first steam control valve 47A to be tested starts the closing operation. The opening operation of the third steam control valve 47C and the fourth steam control valve 47D is completed at the timing when the steam control valve 47A is fully closed. Further, in this opening degree synchronization changing step, the third steam control valve 47C and the fourth steam control valve 47D are maintained in a state where the valve opening degree of the third steam control valve 47C and the fourth steam control valve 47D are aligned. The valve opening degree of the four steam control valve 47D is changed. Further, the opening degree of the first steam control valve 47A is changed from 100% so that the steam flow rate flowing into the steam turbine 10 is not substantially changed before and after the execution of the target valve fully closing process and the opening degree synchronization changing process. In order to make it 0%, the valve opening degree of the third steam control valve 47C and the fourth steam control valve 47D is changed from 25% to 75%.

  The four steam control valves 47 are in the second state by executing the target valve fully closing step and the opening degree synchronization changing step. In this second state, it is confirmed whether or not the first steam control valve 47A to be tested is actually fully closed.

  As described above, in the valve test of the present embodiment, when the first steam control valve 47A to be tested is fully closed, all other steam control valves 47 except the first steam control valve 47A, that is, The second to fourth steam control valves 47B, 47C, 47D are open. For this reason, during the valve test, although steam is not supplied to one nozzle chamber 22A among the four nozzle chambers 22, steam is supplied to all the other three nozzle chambers 22B, 22C, and 22D. The occurrence of double shock during valve testing can be suppressed.

  Further, in the present embodiment, in the opening degree synchronization changing process executed in synchronization with the target valve fully closing process, the valve opening degree of the third steam control valve 47C and the valve opening degree of the fourth steam control valve 47D are aligned. Since the valve opening degree of the third steam control valve 47C and the fourth steam control valve 47D is changed while maintaining the state, the flow rate of the steam flowing into the third nozzle chamber 22C and the fourth nozzle chamber 22D during this process are changed. The flow rate of steam flowing into the tank becomes the same. For this reason, in this embodiment, while the rotor 11 makes one rotation, the force received from the steam that flows out of the third nozzle chamber 22C and the force that the rotor blade 14 of the rotor 11 receives from the steam that flows out of the fourth nozzle chamber 22D. And the transition process from the first state to the second state and the shock applied to the rotor 11 in the second state can be reduced.

  In addition, in the above, the opening degree adjustment process and opening degree synchronous change process performed with respect to the 3rd steam control valve 47C and the 4th steam control valve 47D become a non-target valve opening process.

  Next, the third steam control valve 47C and the fourth steam control valve 47D are maintained at 75%, and the second steam control valve 47B is changed from fully open to fully closed (target valve fully closing process). The first steam control valve 47A is changed from fully closed to fully open in synchronism with this target valve fully closing process (opening synchronization changing process, non-target valve opening process).

  The four steam control valves 47 change from the second state to the third state by executing the target valve full closing step and the opening degree synchronization changing step. In this third state, it is confirmed whether or not the second steam control valve 47B to be tested is actually fully closed.

  As described above, in the valve test of the present embodiment, when the second steam control valve 47B to be tested is fully closed, all the steam control valves 47 other than the second steam control valve 47B are opened. It is in a state. For this reason, it is possible to suppress the occurrence of double shock even during the valve test of the second steam control valve 47B.

  Furthermore, in the valve test of the present embodiment, in the transition process from the second state to the third state, and in the third state, the steam flow rate flowing into the third nozzle chamber 22C and the steam flow rate flowing into the fourth nozzle chamber 22D Are the same. Therefore, the shock applied to the rotor 11 can be reduced even in the transition process from the second state to the third state and in the third state.

  Next, after the four steam control valves 47 are set to the fourth state, the fifth steam control valve 47C is set to the fifth state, and it is confirmed whether or not the third steam control valve 47C is actually fully closed.

  When changing the four steam control valves 47 from the third state to the fourth state, the first steam control valve 47A is fully opened, the valve opening degree of the third steam control valve 47C is maintained at 75%, The valve openings of the steam control valve 47B and the fourth steam control valve 47D are set to 38% (opening adjustment process). Even in this opening degree adjusting process, the second steam adjusting valve 47B and the fourth steam adjusting valve 47D are opened so that the flow rate of the steam flowing into the steam turbine 10 is not substantially changed before and after the opening degree adjusting process. Change the degree.

  When the four steam control valves 47 are changed from the fourth state to the fifth state, the first steam control valve 47A is fully opened. In this state, the third steam control valve 47C having a valve opening degree of 75% is fully closed (target valve full-close process), and the second steam control valve 47B and the second steam control valve 47C are synchronized with the target valve full-close process. The valve opening degree of the four steam control valve 47D is set to 75% (opening degree synchronization changing step).

  As described above, in the valve test of the present embodiment, all the steam control valves 47 other than the third steam control valve 47C are opened when the third steam control valve 47C to be tested is fully closed. It is in a state. For this reason, it is possible to suppress the occurrence of double shock even during the valve test of the third steam control valve 47C.

  Furthermore, in the valve test of the present embodiment, in the transition process from the fourth state to the fifth state, and in the fifth state, the steam flow rate flowing into the second nozzle chamber 22B and the steam flow rate flowing into the fourth nozzle chamber 22D Are the same. Therefore, the shock applied to the rotor 11 can be reduced even in the transition process from the fourth state to the fifth state and in the fifth state.

  Next, after the four steam control valves 47 are set to the sixth state, the seventh state is set to check whether the fourth steam control valve 47D is actually fully closed.

  When the four steam control valves 47 are changed from the fifth state to the sixth state, the first steam control valve 47A is fully opened and the valve opening degree of the fourth steam control valve 47D is maintained at 75%. The valve openings of the steam control valve 47B and the third steam control valve 47C are set to 38% (opening adjustment process). Even in this opening degree adjusting process, the second steam adjusting valve 47B and the third steam adjusting valve 47C are opened so that the flow rate of the steam flowing into the steam turbine 10 does not substantially change before and after the opening degree adjusting process. Change the degree.

  When the four steam control valves 47 are changed from the sixth state to the seventh state, the first steam control valve 47A is fully opened. In this state, the fourth steam control valve 47D having a valve opening degree of 75% is fully closed (target valve full-close process), and the second steam control valve 47B and the second steam control valve 47B are synchronized with the target valve full-close process. The valve opening degree of the three steam control valve 47C is set to 75% (opening degree synchronous changing step).

  As described above, in the valve test of this embodiment, when the fourth steam control valve 47D to be tested is fully closed, all the steam control valves 47 other than the fourth steam control valve 47D are opened. It is in a state. For this reason, the occurrence of double shock can be suppressed even during the valve test of the fourth steam control valve 47D.

  Further, in the valve test of the present embodiment, in the transition process from the sixth state to the seventh state, and in the seventh state, the steam flow rate flowing into the second nozzle chamber 22B and the steam flow rate flowing into the third nozzle chamber 22C Are the same. Therefore, the shock applied to the rotor 11 can be reduced even in the transition process from the sixth state to the seventh state and in the seventh state.

  This completes the test for all four steam control valves 47. Although only the operation of the steam control valve 47 has been described above, the steam stop valve 46 is fully closed immediately after the corresponding steam control valve 47 is fully closed, and the corresponding steam control valve 47 is opened. Fully open before you begin.

  As described above, in the valve test of this embodiment, even when no connection pipe is provided, when the steam control valve 47 to be tested is fully closed, all other steam control valves other than the steam control valve 47 to be tested are provided. Since the valve 47 is in the open state, the occurrence of double shock during the valve test can be suppressed without providing a connecting pipe. Therefore, it is possible to suppress the increase in equipment cost while suppressing the occurrence of double shock during the valve test.

  In the above, the example of performing the valve test in the order of the first steam control valve 47A, the second steam control valve 47B, the third steam control valve 47C, and the fourth steam control valve 47D has been described, but this order can be changed as appropriate. It is.

  In addition, the steam turbine equipment in this embodiment includes four nozzle chambers 22 and a steam control valve 47 that adjusts the flow rate of steam flowing into each nozzle chamber 22. However, even when the number of nozzle chambers 22 is not four, for example, eight, by performing the test method described above, it is possible to suppress the occurrence of double shock during the valve test and to suppress an increase in equipment cost. be able to.

  Further, when the output of the steam turbine 10 is smaller than the rated output, it is possible to suppress the load applied to the bearing device 30 from becoming an uneven load. For this reason, the life of the bearing device 30 can be extended, and vibrations of the rotor 11 due to uneven wear of the bearing device 30 can also be suppressed.

  Note that the bearing device 30 of the present embodiment is a tilting bearing device in which a plurality of bearing pads 31 swing. However, even in the case of a bearing device in which the bearing pad does not swing, when the arrangement of the four nozzle chambers and the four steam stop valves is arranged as shown in FIG. 2, the output of the steam turbine is smaller than the rated output Moreover, it can suppress that the load concerning a bearing apparatus turns into an eccentric load.

  10: Steam turbine, 11: Rotor, 12: Rotor shaft, 13: Rotor blade stage, 13a: Controlled blade stage, 14: Rotor blade, 21: Casing, 22: Nozzle chamber, 22A: First nozzle chamber, 22B : Second nozzle chamber, 22C: third nozzle chamber, 22D: fourth nozzle chamber, 23: steam main channel chamber, 24: exhaust chamber, 25: stationary blade stage, 25a: governing stage nozzle, 26: stationary blade, 26a: Controlled stationary blade, 29: Seal chamber, 30: Bearing device, 31: Bearing pad, 32: Pad support, 33: Bearing case, 40: Steam pipe, 41: Steam main pipe, 41a: First steam branch pipe ( Steam branch pipe), 41b: second steam branch pipe (steam branch pipe), 43a: first nozzle chamber steam pipe (nozzle chamber steam pipe), 43b: second nozzle chamber steam pipe (nozzle chamber steam pipe), 43c: Third nozzle chamber steam pipe (nozzle chamber steam pipe), 43d: Fourth nozzle chamber steam pipe ( 46A: first steam stop valve (steam stop valve), 46B: second steam stop valve (steam stop valve), 46C: third steam stop valve (steam stop valve), 46D: fourth steam Stop valve (steam stop valve), 47A: first steam control valve (steam valve, steam control valve), 47B: second steam control valve (steam valve, steam control valve), 47C: third steam control valve (steam valve) , Steam control valve), 47D: fourth steam control valve (steam valve, steam control valve), 50: control device, 51: reception unit, 52: command output unit

Claims (3)

A steam turbine having a rotor that rotates about an axis, and a casing that rotatably covers the rotor;
A steam valve for adjusting the amount of steam flowing into the steam turbine;
A control device for controlling the steam valve,
In the casing, four nozzle chambers arranged in the circumferential direction around the axis are formed as nozzle chambers into which steam flows.
Of the four nozzle chambers, the first nozzle chamber and the fourth nozzle chamber are disposed above the axis, the second nozzle chamber and the third nozzle chamber are disposed below the axis, and the The first nozzle chamber and the second nozzle chamber are disposed on one side in a lateral direction perpendicular to the axis from the axis, and the third nozzle chamber and the fourth nozzle chamber are in the lateral direction from the axis. Arranged on the other side of
As the steam valve, a first steam valve for adjusting the amount of steam flowing into the first nozzle chamber, a second steam valve for adjusting the amount of steam flowing into the second nozzle chamber, and an inflow into the third nozzle chamber A third steam valve for adjusting the amount of steam, and a fourth steam valve for adjusting the amount of steam flowing into the fourth nozzle chamber,
The control device outputs a valve opening command indicating a valve opening degree to the third steam valve and the fourth steam valve when the output of the steam turbine is set to a predetermined output less than a rated output. , A valve opening command indicating a valve opening larger than the valve opening of the third steam valve and the valve opening of the fourth steam valve is output to the first steam valve and the second steam valve. And
The rotor is configured to rotate to the other side in the lateral direction above the axis.
Steam turbine equipment. The steam turbine equipment according to claim 1,
The first steam valve and the third steam valve are disposed on the one side in the lateral direction from the axis,
The second steam valve and the fourth steam valve are disposed on the other side in the lateral direction with respect to the axis,
Steam turbine equipment. The steam turbine equipment according to claim 1 or 2,
The steam turbine has a bearing device that rotatably supports the rotor,
The bearing device supports a plurality of bearing pads arranged in a circumferential direction around the axis and along an outer peripheral surface of the rotor, and the bearing pads are slidable from a radial side with respect to the axis. A pad support;
Steam turbine equipment.

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