JP2022060818A - Spindle water sealing device of hydraulic machine and hydraulic machine - Google Patents

Abstract

To provide a spindle water sealing device of a hydraulic machine which can eliminate the heat of a seal face, and can suppress the mixing of earth and sand into the seal face.SOLUTION: A spindle water sealing device of a hydraulic machine comprises an inlet chamber into which working water flows from a backpressure chamber, an external communication port communicating with the outside, and a pressurization chamber arranged between the inlet chamber and the external communication port. A first seal part is arranged between the inlet chamber and the pressurization chamber. The first seal part includes a first seal face which is vertical to an axial direction of a spindle. A second seal part is arranged between the pressurization chamber and the external communication port. The second seal part includes a second seal face vertical to the axial direction of the spindle. Pressurized water is supplied to the pressurization chamber by a pressurized water supply part.SELECTED DRAWING: Figure 2

Description

Embodiments of the present invention relate to a spindle water sealing device of a hydraulic machine and a hydraulic machine.

A spindle water sealing device is provided on the spindle connected to the runner of a hydraulic machine such as a turbine or a pump turbine. The spindle water sealing device is a device for suppressing the leakage of the working water that operates the runner to the outside. The spindle water sealing device not only suppresses the leakage of working water, but also has the function of suppressing the leakage of compressed air in the runner that spins during the phase adjustment operation of the pump turbine to the outside.

Such a spindle water sealing device is classified into a device adopting a radial seal structure and a device adopting an axial seal structure.

In the radial seal structure, a plurality of segments are arranged in the circumferential direction of the spindle. Each segment is pressed radially toward the spindle, thereby suppressing the leakage of working water to the outside. However, in the radial seal structure, a gap is formed between the segments adjacent to each other. Working water may leak to the outside through this gap. Since it is difficult to reduce this gap, it may be difficult to reduce the amount of leakage of working water in the radial seal structure.

In the axial seal structure, the stationary side seal member and the rotary side seal member are arranged so as to face each other in the axial direction of the main shaft. The stationary side sealing member and the rotating side sealing member are pressed in the axial direction, thereby suppressing leakage of working water to the outside. The stationary side sealing member and the rotating side sealing member are each formed in a ring shape. More specifically, the stationary side sealing member and the rotating side sealing member are each divided into a plurality of parts in the circumferential direction, and a gap is formed in each of the stationary side sealing member and the rotating side sealing member. However, these gaps can be made smaller. Therefore, in the axial seal structure, the amount of leakage of the working water can be effectively reduced.

As described above, the spindle water sealing device reduces the amount of leakage of the working water, so that the efficiency of the hydraulic machine can be improved. In general, the amount of hydraulic water leaked is negligibly small compared to the flow rate of the hydraulic water flowing through the runner. Therefore, one of the needs for the spindle water sealing device is to suppress the cost related to the maintenance of the hydraulic machine due to the leakage of the working water.

For example, in the axial seal structure, the rotary side seal ring rotates and slides with respect to the stationary side seal ring. As a result, it is conceivable that the sealing surface, which is the contact surface between the rotating side sealing ring and the stationary side sealing ring, generates heat due to friction, and the sealing surface may be burnt out. Therefore, cooling water is supplied to the gap between the rotating side sealing ring and the stationary side sealing ring to remove heat from the sealing surface. In a pump turbine, the pressure of the working water in the runner is relatively high, so that the pressure of the working water in the spindle sealing device can also be high. In this case, the pressing force of the sealing surface is increased in order to suppress the leakage of the working water, and the temperature of the sealing surface may rise. If the heat removal of the sealing surface is insufficient, the sealing surface may be burnt out.

In addition, earth and sand are mixed in the working water. Therefore, water containing earth and sand may flow into the gap between the stationary side seal ring and the rotating side seal ring. In this case, wear of the sealing surface may be accelerated.

U.S. Patent Application Publication No. 2017/0370475 U.S. Patent Application Publication No. 2019/0003481 U.S. Patent Application Publication No. 2019/0063610 U.S. Patent Application Publication No. 2010/0327533 U.S. Patent Application Publication No. 2018/0187566

The embodiment is made in consideration of such a point, and is a spindle water sealing device and hydraulic power of a hydraulic machine capable of removing heat from the sealing surface and suppressing sediment from being mixed into the sealing surface. The purpose is to provide a machine.

The main shaft water sealing device of the hydraulic machine according to the embodiment is provided on the main shaft connected to the runner of the hydraulic machine, and suppresses the leakage of the working water in the back pressure chamber formed between the runner and the upper cover to the outside. It is a device to do. The main shaft water sealing device of a hydraulic machine has an inlet chamber into which working water flows from the back pressure chamber, an external communication port communicating with the outside, and a pressurizing chamber provided between the inlet chamber and the external communication port. I have. A first seal portion is provided between the entrance chamber and the pressurizing chamber. The first seal portion includes a first seal surface perpendicular to the axial direction of the main shaft. A second seal is provided between the pressurizing chamber and the external communication port. The second seal portion includes a second seal surface perpendicular to the axial direction of the main shaft. Pressurized water is supplied to the pressurized chamber by the pressurized water supply unit.

The hydraulic machine according to the embodiment includes a runner, a spindle connected to the runner, an upper cover located above the runner, and a spindle water sealing device for the hydraulic machine described above.

According to the embodiment, heat can be removed from the sealing surface and sediment contamination on the sealing surface can be suppressed.

FIG. 1 is a cross-sectional view of a meridional surface showing a Francis turbine according to the present embodiment. FIG. 2 is a vertical sectional view showing a spindle water sealing device according to the present embodiment. FIG. 3 is a partially enlarged cross-sectional view showing the lower seal pressing portion shown in FIG.

Hereinafter, the spindle water sealing device and the hydraulic machine of the hydraulic machine according to the embodiment of the present invention will be described with reference to the drawings.

The spindle water sealing device and the hydraulic machine of the hydraulic machine according to the present embodiment will be described with reference to FIGS. 1 to 3. Here, first, a Francis turbine, which is an example of a hydraulic machine, will be described with reference to FIG.

As shown in FIG. 1, the Francis turbine 1 includes a spiral casing 2 in which working water flows from an upper pond through a penstock (not shown), a plurality of stay vanes 3, and a plurality of stay vanes 3 during operation of the turbine. It has a guide vane 4 and a runner 5.

The stay vane 3 is a member for guiding the working water flowing into the casing 2 to the guide vanes 4 and the runner 5. The stay vanes 3 are arranged at predetermined intervals in the circumferential direction. A flow path through which working water flows is formed between the stay vanes 3.

The guide vane 4 is a member for guiding the inflowing working water to the runner 5. The guide vanes 4 are arranged at predetermined intervals in the circumferential direction. A flow path through which working water flows is formed between the guide vanes 4. Each guide vane 4 is configured to be rotatable, and the flow rate of the working water flowing into the runner 5 can be adjusted by rotating each guide vane 4 to change the opening degree. In this way, the amount of power generated by the generator 7, which will be described later, can be adjusted.

The runner 5 is configured to be rotatable about the rotation axis X with respect to the casing 2. The runner 5 is rotationally driven by the working water flowing from the casing 2 during operation of the turbine. That is, the runner 5 is a member for converting the pressure energy of the working water flowing into the runner 5 into rotational energy.

The runner 5 has a crown 5a connected to a spindle 6 described later, a band 5b provided on the outer peripheral side of the crown 5a, and a plurality of runner blades 5c provided between the crown 5a and the band 5b. are doing. Of these, the runner blades 5c are arranged at predetermined intervals in the circumferential direction. A flow path through which working water flows is formed between the runner blades 5c.

A spindle 6 is connected to the runner 5. The spindle 6 is configured to be rotatable around a rotation axis X extending in the vertical direction together with the runner 5. The spindle 6 extends along a direction along the rotation axis X (hereinafter, referred to as an axial direction d).

A generator 7 is connected to the spindle 6. The generator 7 is configured to generate electricity by transmitting the rotational energy of the runner 5 during operation of the water turbine.

The generator 7 also has a function as an electric motor, and may be configured to rotationally drive the runner 5 by supplying electric power. In this case, the working water of the lower pond can be sucked up through the suction pipe 8 and discharged to the upper pond, and the Francis turbine 1 can be pumped (pumped) as a pump turbine. At this time, the opening degree of the guide vane 4 is changed so as to have an appropriate pumping amount according to the pump head.

A suction pipe 8 is provided on the downstream side of the runner 5 when the water turbine is operated. The suction pipe 8 is connected to a lower pond or a drainage channel (not shown), and the hydraulic water that has been rotationally driven by the runner 5 recovers the pressure and is discharged to the lower pond or the drainage channel.

As shown in FIG. 2, an upper cover 9 is provided above the crown 5a of the runner 5. A back pressure chamber 10 is provided between the crown 5a of the runner 5 and the upper cover 9. A part of the working water that has flowed through the flow path of the guide vane 4 flows into the back pressure chamber 10 as a leak flow during the power generation operation. More specifically, a gap is formed between the guide vane 4 and the runner 5, and the working water flows into the back pressure chamber 10 from this gap. In order to prevent the hydraulic water flowing into the back pressure chamber 10 from leaking to the outside, a spindle water sealing device 20 described later is provided on the spindle 6.

Next, with reference to FIGS. 2 and 3, the spindle water sealing device of the hydraulic machine according to the present embodiment (hereinafter, simply referred to as the spindle water sealing device 20) will be described. The spindle water sealing device 20 is a device provided on the spindle 6 described above and for suppressing leakage of working water in the back pressure chamber 10 formed between the runner 5 and the upper cover 9 to the outside.

As shown in FIG. 2, the spindle water sealing device 20 includes an inlet chamber 21, an external communication port 22, a pressurizing chamber 23, a lower seal portion 40, a lower seal pressing portion 50, and an upper seal portion 60. The upper seal pressing unit 70, the pressurized water supply unit 80, and the exhaust unit 90 are provided.

Working water flows into the inlet chamber 21 from the back pressure chamber 10. The entrance chamber 21 may be mainly partitioned by the crown 5a of the runner 5, the upper cover 9, and the coupling cover 28 described later. The entrance chamber 21 is divided into a lower entrance chamber 24 and an upper entrance chamber 25 by a coupling cover 28. The lower entrance chamber 24 and the upper entrance chamber 25 communicate with each other through a gap between the coupling cover 28 and the upper cover 9. As a result, the working water in the lower inlet chamber 24 flows into the upper inlet chamber 25 through the gap between the coupling cover 28 and the upper cover 9. The pressure of the working water in the upper inlet chamber 25 and the pressure of the working water in the lower inlet chamber 24 are substantially equal.

The entrance chamber 21 and the back pressure chamber 10 are separated by a seal liner 26. The seal liner 26 suppresses the inflow of working water from the back pressure chamber 10 to the lower inlet chamber 24. However, a gap is formed between the seal liner 26 and the crown 5a, and a gap is formed between the seal liner 26 and the upper cover 9. Through these gaps, a part of the working water in the back pressure chamber 10 flows into the lower inlet chamber 24. At this time, the working water is depressurized by the seal liner 26 and flows into the lower inlet chamber 24.

A balance hole 27 communicates with the lower entrance chamber 24. The balance hole 27 is formed on the main shaft 6. A part of the working water in the lower inlet chamber 24 flows out to the downstream portion of the runner blade 5c through the balance hole 27.

A coupling cover 28 is attached to the spindle 6. The coupling cover 28 covers the fastening member 11 that connects the spindle 6 to the crown 5a of the runner 5. The coupling cover 28 is formed in a ring shape when viewed in the axial direction d, and is formed in an inverted L shape when viewed in cross section. The outer peripheral surface of the coupling cover 28 is close to the inner peripheral surface of the upper cover 9, but fluid can flow through the gap between the coupling cover 28 and the upper cover 9.

The external communication port 22 communicates with the outside of the main shaft water sealing device 20. The external communication port 22 is located above the main shaft water sealing device 20. The external communication port 22 is partitioned by a communication port partitioning member 29.

The pressurizing chamber 23 is provided between the entrance chamber 21 and the external communication port 22. Pressurized water is supplied to the pressurizing chamber 23 from the pressurized water supply unit 80. Therefore, the pressure in the pressurizing chamber 23 is higher than the pressure in the inlet chamber 21. The pressurizing chamber 23 mainly includes an upper cover 9, a coupling cover 28, a sleeve 30 provided on the outer peripheral surface of the main shaft 6, a housing 31, a lower retainer 32, an apparatus cover 33, and an upper retainer 34. And the mating ring 35, and may be partitioned by.

The housing 31 is fixed to the upper cover 9. The housing 31 is an example of the first fixing member. The housing 31 includes an outer peripheral side portion 31a attached to the upper end portion of the upper cover 9 and an inner peripheral side portion 31b extending radially inward from the outer peripheral side portion 31a toward the main shaft 6. The wall portion 31c extends upward from the portion between the outer peripheral side portion 31a and the inner peripheral side portion 31b. The housing 31 is composed of an outer peripheral side portion 31a, an inner peripheral side portion 31b, and a wall portion 31c, and the housing 31 is formed in an inverted T shape in a cross-sectional view. The housing 31 is formed in a ring shape so as to extend in the circumferential direction of the main shaft 6 when viewed in the axial direction d.

The pressurizing chamber 23 is divided into a lower pressurizing chamber 36 and an upper pressurizing chamber 37 by an inner peripheral side portion 31b of the housing 31. The lower pressurizing chamber 36 is formed below the inner peripheral side portion 31b, and the upper pressurizing chamber 37 is formed above the inner peripheral side portion 31b. The lower pressurizing chamber 36 and the upper pressurizing chamber 37 communicate with each other through a gap between the mating ring 35 and the inner peripheral side portion 31b of the housing 31. As a result, the pressurized water in the upper pressurizing chamber 37 flows into the lower pressurizing chamber 36 through the gap between the mating ring 35 and the inner peripheral side portion 31b. The pressure of the pressurized water in the upper pressurizing chamber 37 and the pressure of the pressurized water in the lower pressurizing chamber 36 are substantially equal to each other.

As shown in FIG. 3, a seal ring s1 is provided between the outer peripheral side portion 31a of the housing 31 and the upper cover 9. This prevents the fluid from flowing through the gap between the outer peripheral side portion 31a and the upper cover 9.

As shown in FIGS. 2 and 3, the lower retainer 32 is provided below the housing 31 and on the inner peripheral side of the upper cover 9. The lower retainer 32 is an example of the first holding member. The lower retainer 32 is movable in the axial direction d with respect to the housing 31. More specifically, the lower retainer 32 is formed in a ring shape so as to extend in the circumferential direction of the main shaft 6 when viewed in the axial direction d. A slide guide 38 is provided on the outer peripheral surface of the lower retainer 32. The slide guide 38 is slidable with respect to the cylindrical inner peripheral surface of the upper cover 9. The lower retainer 32 is located above the coupling cover 28 and faces the coupling cover 28. The lower retainer 32 holds a lower seal ring 42 described later on its lower surface. In this way, the lower retainer 32, together with the lower seal ring 42, is configured to be movable in the axial direction d with respect to the housing 31 and the upper cover 9. The slide guide 38 has a sealing performance. That is, the slide guide 38 suppresses the flow of the fluid through the gap between the slide guide 38 and the inner peripheral surface of the upper cover 9.

As shown in FIG. 2, the device cover 33 is fixed to the upper cover 9 via the housing 31. The device cover 33 is an example of the second fixing member. The device cover 33 is attached to the upper end of the wall portion 31c of the housing 31. The device cover 33 extends in the radial direction in a cross-sectional view, and extends inward in the radial direction from the wall portion 31c. The device cover 33 is formed in a ring shape so as to extend in the circumferential direction of the main shaft 6 when viewed in the axial direction d. As shown in FIG. 3, a seal ring s2 is provided between the device cover 33 and the upper end of the wall portion 31c of the housing 31. This prevents the fluid from flowing through the gap between the wall portion 31c and the device cover 33. As shown in FIG. 2, the communication port partitioning member 29 described above is attached to the upper surface of the device cover 33.

The upper retainer 34 is provided on the inner peripheral side of the device cover 33. The upper retainer 34 is an example of the second holding member. The upper retainer 34 is movable in the axial direction d with respect to the device cover 33. More specifically, the upper retainer 34 is formed in a ring shape so as to extend in the circumferential direction of the main shaft 6 when viewed in the axial direction d. The outer peripheral surface of the upper retainer 34 is slidable with respect to the inner peripheral surface of the device cover 33. The upper retainer 34 holds the upper seal ring 62, which will be described later, on the lower surface thereof. In this way, the upper retainer 34 is configured to be movable in the axial direction d with respect to the device cover 33 together with the upper seal ring 62. A seal ring s3 is provided between the upper retainer 34 and the device cover 33. This prevents the fluid from flowing through the gap between the upper retainer 34 and the device cover 33. The upper retainer 34 includes an upper retainer main body 34a and an upper spring receiver 34b extending radially outward from the lower portion of the upper retainer main body 34a. The upper spring receiver 34b is a portion that receives the urging force of the upper spring 71, which will be described later.

The mating ring 35 is provided below the upper retainer 34. The mating ring 35 is attached to the sleeve 30 described above. The mating ring 35 faces the upper retainer 34. The mating ring 35 is formed in a ring shape when viewed in the axial direction d, and is arranged at the same height position as the inner peripheral side portion 31b of the housing 31. The outer peripheral surface of the mating ring 35 is close to the inner peripheral surface of the inner peripheral side portion 31b, but the fluid can flow through the gap between the mating ring 35 and the inner peripheral side portion 31b. There is.

As shown in FIGS. 2 and 3, the lower seal portion 40 is provided between the inlet chamber 21 and the pressurizing chamber 23. The lower seal portion 40 is an example of the first seal portion. The lower seal portion 40 suppresses the flow of fluid between the upper inlet chamber 25 and the lower pressurizing chamber 36. The lower seal portion 40 includes a lower seal surface 41 perpendicular to the axial direction d of the main shaft 6. The lower sealing surface 41 is an example of the first sealing surface. The lower seal portion 40 has an axial seal structure.

The lower seal portion 40 includes a lower seal ring 42 held by the lower retainer 32 and a lower sliding ring 43 held by the spindle 6. The lower seal ring 42 is an example of the first stationary side seal member, and the lower sliding ring 43 is an example of the first rotation side seal member. The contact surface between the lower seal ring 42 and the lower sliding ring 43 constitutes the above-mentioned lower seal surface 41. More specifically, the lower sliding ring 43 is located below the lower seal ring 42. The lower surface of the lower seal ring 42 and the upper surface of the lower sliding ring 43 form a lower seal surface 41.

The lower seal ring 42 is located below the lower retainer 32 and is held on the lower surface of the lower retainer 32. The lower seal ring 42 may be made of a resin material having good slipperiness. Further, the lower seal ring 42 is formed in a ring shape as a whole when viewed in the axial direction d. The lower seal ring 42 may be divided into a plurality of members arranged in the circumferential direction of the main shaft 6.

The lower sliding ring 43 is located above the coupling cover 28 and is held on the upper surface of the coupling cover 28. The lower sliding ring 43 may be made of a metal material having good slipperiness. Further, the lower sliding ring 43 is formed in a ring shape as a whole when viewed in the axial direction d. The lower sliding ring 43 may be divided into a plurality of members arranged in the circumferential direction of the main shaft 6.

The material of the lower seal ring 42 and the material of the lower sliding ring 43 may be selected so that the coefficient of dynamic friction becomes smaller by combining both. In this case, heat generation due to friction on the sealing surface can be suppressed, and the required heat removal amount can be reduced. Further, the material of the lower seal ring 42 and the material of the lower sliding ring 43 may be selected so as to have high sediment wear resistance by combining both.

The lower seal pressing portion 50 exerts a pressing force on the lower seal surface 41. The lower seal ring 42 and the lower sliding ring 43 are pressed against each other in the axial direction d by the lower seal pressing portion 50. The lower seal pressing portion 50 is an example of the first seal pressing portion. The lower seal pressing portion 50 according to the present embodiment presses the lower seal ring 42 downward toward the lower sliding ring 43. A plurality of lower seal pressing portions 50 may be arranged in the circumferential direction of the spindle 6.

The surface pressure of the lower sealing surface 41 may be lower than the surface pressure of the upper sealing surface 61, which will be described later. Here, the surface pressure of the lower sealing surface 41 means a pressing force per unit area acting on the lower sealing surface 41. The same applies to the surface pressure of the upper sealing surface 61, which will be described later.

The lower seal pressing portion 50 presses the lower retainer 32 against the housing 31 toward the lower sliding ring 43. For example, as shown in FIG. 3, the lower seal pressing portion 50 may include a rod 51, a lower spring receiver 52, and a lower spring 53.

The rod 51 is attached to the lower retainer 32. A threaded portion is formed in the lower portion of the rod 51, and this male threaded portion is screwed into a screw hole provided in the lower retainer 32. A nut 54 is tightened to the threaded portion of the rod 51, and the nut 54 prevents the rod 51 from loosening to the lower retainer 32.

The rod 51 extends in the axial direction d. The rod 51 penetrates the inner peripheral side portion 31b of the housing 31 and extends upward from the inner peripheral side portion 31b.

The lower spring receiver 52 is attached to the rod 51. The lower spring receiving 52 is an example of the first receiving portion. The lower spring receiver 52 is located above the inner peripheral side portion 31b of the housing 31. The lower spring receiver 52 may be composed of two nuts 52a. The two nuts 52a are fastened to the male threaded portion provided on the upper part of the rod 51.

The lower spring 53 is interposed between the lower spring receiver 52 and the inner peripheral side portion 31b of the housing 31. The lower spring is an example of an urging member. The lower spring 53 is formed in a coil shape, and the rod 51 penetrates inside the lower spring 53. The lower spring 53 presses the upper surface of the inner peripheral side portion 31b and the lower surface of the lower spring receiver 52. The rod 51 receives an upward urging force from the lower spring 53.

The lower seal pressing portion 50 can adjust the surface pressure of the lower seal surface 41. More specifically, the magnitude of the urging force of the lower spring 53 can be adjusted by moving the lower spring receiver 52 described above in the vertical direction. That is, the pressing force of the lower seal ring 42 pressing the lower sliding ring 43 corresponds to the force obtained by subtracting the urging force of the lower spring 53 from the own weight of the lower retainer 32. Therefore, by adjusting the magnitude of the urging force of the lower spring 53, the pressing force of the lower seal ring 42 pressing the lower sliding ring 43 can be adjusted. As a result, the surface pressure of the lower sealing surface 41 can be adjusted. When moving the lower spring receiver 52, for example, the device cover 33 may be removed from the housing 31.

As shown in FIGS. 2 and 3, the upper seal portion 60 is provided between the pressurizing chamber 23 and the external communication port 22. The upper seal portion 60 is an example of the second seal portion. The upper seal portion 60 suppresses the flow of fluid between the upper pressurizing chamber 37 and the external communication port 22. The upper seal portion 60 includes an upper seal surface 61 perpendicular to the axial direction d of the main shaft 6. The upper sealing surface 61 is an example of the second sealing surface. The upper seal portion 60 has an axial d-seal structure.

The upper seal portion 60 includes an upper seal ring 62 held by the upper retainer 34 and an upper sliding ring 63 held by the spindle 6. The upper seal ring 62 is an example of the second stationary side seal member, and the upper sliding ring 63 is an example of the second rotation side seal member. The contact surface between the upper seal ring 62 and the upper sliding ring 63 constitutes the above-mentioned upper seal surface 61. More specifically, the upper sliding ring 63 is located below the upper seal ring 62. The lower surface of the upper seal ring 62 and the upper surface of the upper sliding ring 63 constitute an upper seal surface 61.

The upper seal ring 62 is located below the upper retainer 34 and is held on the lower surface of the upper retainer 34. The upper seal ring 62 may be configured in the same manner as the lower seal ring 42 described above.

The upper sliding ring 63 is located above the mating ring 35 and is held on the upper surface of the mating ring 35. The upper sliding ring 63 may be configured in the same manner as the lower sliding ring 43 described above.

The upper seal pressing portion 70 exerts a pressing force on the upper seal surface 61. The upper seal ring 62 and the upper sliding ring 63 are pressed against each other in the axial direction d by the upper seal pressing portion 70. The upper seal pressing portion 70 is an example of the second seal pressing portion. The upper seal pressing portion 70 according to the present embodiment presses the upper seal ring 62 downward toward the upper sliding ring 63. A plurality of upper seal pressing portions 70 may be arranged in the circumferential direction of the spindle 6.

The upper seal pressing portion 70 presses the upper retainer 34 against the device cover 33 toward the upper sliding ring 63. For example, as shown in FIG. 3, the upper seal pressing portion 70 may include an upper spring 71. The surface pressure of the upper sealing surface 61 may be higher than the surface pressure of the lower sealing surface 41.

The upper spring 71 is interposed between the upper retainer 34 and the device cover 33. More specifically, the upper spring 71 is interposed between the upper spring receiver 34b of the upper retainer 34 and the inner peripheral side portion 31b of the device cover 33. The upper spring 71 is formed in a coil shape and presses the upper spring receiver 34b and the inner peripheral side portion 31b of the device cover 33. The upper seal ring 62 receives a downward urging force from the upper spring 71.

As shown in FIG. 2, the pressurized water supply unit 80 is configured to supply pressurized water to the pressurized chamber 23. For example, the pressurized water supply unit 80 may pressurize the working water in the suction pipe 8 and supply it to the pressurizing chamber 23 as pressurized water. More specifically, the pressurized water supply unit 80 may include an intake port 81, a supply port 82, a supply line 83, a pressurized pump 84, and a strainer 85.

As shown in FIG. 1, the water intake port 81 is provided in the suction pipe 8. An intake port 81 may be provided in a portion of the suction pipe 8 on the downstream side of the bent portion.

As shown in FIG. 2, the supply port 82 is provided in the pressurizing chamber 23. The supply port 82 may be provided in the upper pressurizing chamber 37. In this case, pressurized water is supplied to the upper pressurizing chamber 37. However, the supply port 82 may be provided in the lower pressurizing chamber 36.

The supply line 83 communicates the water intake port 81 and the supply port 82, and supplies the hydraulic water taken in from the water intake port 81 to the supply port 82. The supply line 83 is provided with a pressurizing pump 84, and the working water is pressurized. Further, the supply line 83 is provided with a strainer 85, and foreign matter contained in the working water is removed. Examples of foreign substances include earth and sand such as pebbles or sand. The strainer 85 may be provided on the downstream side of the pressurizing pump 84, or may be provided on the upstream side of the pressurizing pump 84.

In this way, the pressurized water supply unit 80 pressurizes the working water in the suction pipe 8 and supplies it to the pressurizing chamber 23. As a result, the pressure in the pressurizing chamber 23 becomes higher than the pressure in the inlet chamber 21. The pressure in the pressurizing chamber 23 may be adjusted by adjusting the discharge force of the pressurizing pump 84.

Further, by adjusting the pressure in the pressurizing chamber 23, the surface pressure of the upper sealing surface 61 can be adjusted. That is, the pressing force of the upper seal ring 62 pressing the upper sliding ring 63 corresponds to the force obtained by subtracting the pressure of the pressurizing chamber 23 from the urging force of the upper spring 71. As a result, the surface pressure of the upper sealing surface 61 can be reduced by increasing the pressure in the pressurizing chamber 23. On the other hand, by reducing the pressure in the pressurizing chamber 23, the surface pressure of the upper sealing surface 61 can be increased. When the pressure in the pressurizing chamber 23 is adjusted, the surface pressure of the lower sealing surface 41 also changes. Therefore, the surface pressure of the lower seal surface 41 can be adjusted by adjusting the position of the lower spring receiver 52 of the lower seal pressing portion 50. In this case, the surface pressure of the lower sealing surface 41 can be made lower than the surface pressure of the upper sealing surface 61.

The exhaust unit 90 is configured to exhaust the gas in the inlet chamber 21 to the outside. For example, the exhaust unit 90 may include an exhaust port 91, an exhaust line 92, and an exhaust valve 93.

As shown in FIG. 2, the exhaust port 91 is provided in the inlet chamber 21. The exhaust port 91 may be provided in the upper inlet chamber 25.

The exhaust line 92 communicates with the exhaust port 91, and the gas in the inlet chamber 21 is discharged to the outside from the exhaust port 91. The exhaust line 92 is provided with an exhaust valve 93. For example, when the runner 5 is idled during the phase adjustment operation of the pump turbine, the flow path in the Francis turbine 1 is filled with air. After the phase adjustment operation is completed, the air in the flow path can be discharged to the outside through the inlet chamber 21 and the exhaust line 92 by opening the exhaust valve 93. As a result, the flow path of the Francis turbine 1 can be quickly filled with the working water.

In the present embodiment having such a configuration, the flow of working water during operation of the water turbine will be described.

During operation of the turbine, the hydraulic water flowing through the flow path of the guide vane 4 flows into the flow path of the runner 5, and the runner 5 is rotationally driven. As a result, the runner 5 rotates about the rotation axis X together with the spindle 6. The hydraulic water obtained by rotationally driving the runner 5 is discharged from the flow path of the runner 5 and flows into the suction pipe 8. Then, the working water is discharged to the lower pond or the flood channel through the suction pipe 8.

As the runner 5 and the spindle 6 rotate, the lower sliding ring 43 of the lower seal portion 40 rotates. Then, the lower seal surface 41 is formed by the lower seal ring 42 and the lower sliding ring 43. Similarly, the upper sliding ring 63 of the upper seal portion 60 rotates together with the mating ring 35. Then, the upper seal surface 61 is formed by the upper seal ring 62 and the upper sliding ring 63.

During the operation of the turbine, a part of the working water flowing through the flow path of the guide vane 4 flows into the back pressure chamber 10 formed between the crown 5a of the runner 5 and the upper cover 9. The working water in the back pressure chamber 10 is depressurized by the seal liner 26 and flows into the lower inlet chamber 24. Sediment may be mixed in the working water flowing into the lower entrance chamber 24. A part of the working water that has flowed into the lower entrance chamber 24 flows into the upper inlet chamber 25.

Pressurized water is supplied to the upper pressurized chamber 37 by the pressurized water supply unit 80. More specifically, a part of the working water flowing through the suction pipe 8 is taken in from the intake port 81 and pressurized by the pressurizing pump 84 in the supply line 83. The pressurized hydraulic water passes through the strainer 85 to remove foreign matter such as earth and sand. After that, the working water is supplied to the upper pressurizing chamber 37 from the supply port 82 as pressurized water. As a result, the pressure in the upper pressurizing chamber 37 and the pressure in the lower pressurizing chamber 36 are increased. As a result, the pressure in the pressurizing chamber 23 becomes higher than the pressure in the inlet chamber 21.

As described above, the surface pressure of the lower sealing surface 41 is lower than the surface pressure of the upper sealing surface 61. As a result, the pressurized water in the pressurizing chamber 23 flows into the gap between the lower seal ring 42 and the lower sliding ring 43, and a water film of the pressurized water is formed in the gap. Then, the inflowing pressurized water flows out to the inlet chamber 21. As a result, the lower sealing surface 41 is cooled by the pressurized water and heat is removed. Further, the hydraulic water in the inlet chamber 21 is suppressed from flowing into the pressurizing chamber 23. The working water in the inlet chamber 21 is discharged from the balance hole 27 to the flow path of the runner 5.

On the other hand, the surface pressure of the upper sealing surface 61 of the upper sealing portion 60 is higher than the surface pressure of the lower sealing surface 41. As a result, the pressurized water in the pressurizing chamber 23 is suppressed from flowing out to the external communication port 22. Therefore, it is suppressed that the pressure in the pressurizing chamber 23 decreases, and as a result, the working water in the inlet chamber 21 is suppressed from flowing into the pressurizing chamber 23.

As described above, according to the present embodiment, the pressurizing chamber 23 is provided between the entrance chamber 21 communicating with the back pressure chamber 10 and the external communication port 22 communicating with the outside. A lower seal portion 40 is provided between the pressurizing chamber 23 and the inlet chamber 21, and an upper seal portion 60 is provided between the pressurizing chamber 23 and the external communication port 22. Pressurized water is supplied to the pressurizing chamber 23. As a result, the pressure in the pressurizing chamber 23 can be made higher than the pressure in the inlet chamber 21, and the pressurized water in the pressurizing chamber 23 can flow into the lower sealing surface 41 of the lower sealing portion 40. Can be done. Therefore, the lower sealing surface 41 can be effectively heat-removed by pressurized water. Further, it is possible to prevent the working water in the inlet chamber 21 from flowing into the pressurizing chamber 23. Therefore, even when the working water in the inlet chamber 21 is mixed with earth and sand, it is possible to prevent the lower seal surface 41 from being worn by the earth and sand. As a result, heat can be removed from the sealing surface and sediment contamination on the sealing surface can be suppressed.

Further, according to the present embodiment, as described above, the pressure in the pressurizing chamber 23 can be made higher than the pressure in the inlet chamber 21. As a result, it is possible to prevent the working water in the inlet chamber 21 from flowing into the pressurizing chamber 23. Therefore, it is possible to suppress the transmission of the hydraulic pulsation to the upper seal portion 60, and it is possible to suppress the deterioration of the sealing performance of the upper seal portion 60.

Further, according to the present embodiment, the lower retainer 32 holding the lower seal ring 42 is movable in the axial direction d with respect to the housing 31, and the lower seal pressing portion 50 is the housing 31. The lower retainer 32 is pressed toward the lower sliding ring 43. As a result, the lower seal ring 42 can be effectively pressed against the lower sliding ring 43, and the sealing performance of the lower seal surface 41 can be effectively enhanced. Therefore, it is possible to further suppress the transmission of the hydraulic pulsation to the upper seal portion 60, and further suppress the inflow of the hydraulic water in the inlet chamber 21 to the lower seal surface 41.

Further, according to the present embodiment, the lower seal pressing portion 50 can adjust the surface pressure of the lower seal surface 41. As a result, the sealing performance of the lower sealing surface 41 can be adjusted according to the worn state of the lower sealing surface 41 and the worn state of the upper sealing surface 61. Further, the surface pressure of the upper sealing surface 61 can be made higher than the surface pressure of the lower sealing surface 41. As a result, the pressurized water in the pressurizing chamber 23 can be suppressed from flowing out to the external communication port 22, and can flow into the inlet chamber 21. Therefore, it is possible to remove heat from the lower sealing surface 41 while maintaining the pressure in the pressurizing chamber 23, and it is possible to prevent the lower sealing surface 41 from being worn by earth and sand.

Further, according to the present embodiment, the magnitude of the urging force of the lower spring 53 is adjusted by adjusting the position of the lower spring receiver 52 attached to the rod 51 of the lower seal pressing portion 50. Can be done. Therefore, the surface pressure of the lower sealing surface 41 can be adjusted.

Further, according to the present embodiment, the upper retainer 34 holding the upper seal ring 62 is movable in the axial direction d with respect to the device cover 33, and the upper seal pressing portion 70 is attached to the device cover 33. On the other hand, the upper retainer 34 is pressed toward the upper sliding ring 63. As a result, the upper seal ring 62 can be effectively pressed against the upper sliding ring 63, and the sealing performance of the upper seal surface 61 can be effectively enhanced. Therefore, the pressurized water in the pressurizing chamber 23 can be suppressed from flowing out to the external communication port 22, and the pressure in the pressurizing chamber 23 can be maintained.

Further, according to the present embodiment, the pressurized water supply unit 80 pressurizes the working water in the suction pipe 8 provided on the downstream side of the runner 5 and supplies the pressurized water to the pressurizing chamber 23 as pressurized water. This makes it possible to suppress the influence on the flow of the working water in the flow path of the runner 5 in order to take out the working water for supplying the pressurized water. Therefore, it is possible to prevent the efficiency of the Francis turbine 1 from decreasing.

Further, according to the present embodiment, the pressurized water supply unit 80 includes a strainer 85 for removing foreign substances in the pressurized water. As a result, it is possible to prevent foreign substances such as earth and sand from being mixed into the pressurized water in the pressurizing chamber 23. Therefore, it is possible to prevent the lower seal surface 41 and the upper seal surface 61 from being worn by earth and sand.

Further, according to the present embodiment, the gas in the inlet chamber 21 is discharged to the outside by the exhaust unit 90. As a result, when the pump turbine is switched from the phase adjustment operation to the power generation operation, the air filled in the flow path in the Francis turbine 1 can be discharged to the outside through the inlet chamber 21. Therefore, the working water can be quickly filled in the flow path. In this case, it is possible to quickly shift to the power generation operation, and in the pump turbine, it is possible to quickly shift to not only the power generation operation but also the pumping operation.

In the above-described embodiment, the spindle water sealing device 20 includes a lower seal portion 40 and an upper seal portion 60, and an example having a two-stage seal structure has been described. However, this is not limited to this. The spindle water sealing device 20 may have a multi-stage sealing structure having three or more stages.

Further, in the above-described embodiment, the lower seal ring 42 is held by the lower retainer 32 which is a stationary member, and the lower sliding ring 43 is held by the coupling cover 28 which is a rotating member. I explained the example. However, the present invention is not limited to this, and the lower seal ring 42 may be held by the coupling cover 28, and the lower sliding ring 43 may be held by the lower retainer 32. The same applies to the upper seal ring 62 and the upper sliding ring 63.

Further, in the above-described embodiment, the Francis turbine 1 has been described as an example of the hydraulic machine, but the present invention is not limited to this. The spindle water sealing device 20 according to the present embodiment may be applied to a water turbine other than the Francis water turbine 1.

According to the above-described embodiment, heat can be removed from the sealing surface and sediment contamination on the sealing surface can be suppressed.

Although embodiments and modifications of the present invention have been described, these embodiments and modifications are presented as examples and are not intended to limit the scope of the invention. These novel embodiments and modifications can be implemented in various other embodiments, and various omissions, replacements, and changes can be made without departing from the gist of the invention. These embodiments and modifications thereof are included in the scope and gist of the invention, and are also included in the scope of the invention described in the claims and the equivalent scope thereof. Further, as a matter of course, it is also possible to partially and appropriately combine these embodiments and modifications within the scope of the gist of the present invention.

1: Francis water wheel, 5: runner, 6: spindle, 8: suction pipe, 9: top cover, 10: back pressure chamber, 20: spindle water sealing device, 21: inlet chamber, 22: external communication port, 23: addition Pressure chamber, 31: Housing, 32: Lower retainer, 33: Device cover, 34: Upper retainer, 40: Lower seal part, 41: Lower seal surface, 42: Lower seal ring, 43: Lower sliding ring , 50: Lower seal pressing part, 51: Rod, 52: Lower spring receiver, 53: Lower spring, 60: Upper seal part, 61: Upper seal surface, 62: Upper seal ring, 63: Upper sliding ring, 70: Upper seal pressing part, 80: Pressurized water supply part, 85: Strainer, 90: Exhaust part, d: Axial direction

Claims (9)

A spindle water sealing device for a hydraulic machine, which is provided on a spindle connected to a runner of a hydraulic machine and suppresses leakage of working water in a back pressure chamber formed between the runner and the upper cover to the outside.
An inlet chamber into which the working water flows from the back pressure chamber and
An external communication port that communicates with the outside and
A pressurizing chamber provided between the entrance chamber and the external communication port,
A first seal portion provided between the inlet chamber and the pressurizing chamber and including a first seal surface perpendicular to the axial direction of the main shaft, and a first seal portion.
A second sealing portion provided between the pressurizing chamber and the external communication port and including a second sealing surface perpendicular to the axial direction of the spindle, and a second sealing portion.
A spindle water sealing device for a hydraulic machine, comprising a pressurized water supply unit for supplying pressurized water to the pressurized chamber. The first fixing member fixed to the upper cover and
A first holding member that can move in the axial direction with respect to the first fixing member,
A first seal pressing portion that exerts a pressing force on the first sealing surface is provided.
The first seal portion includes a first stationary side seal member held by the first holding member and a first rotation side seal member held by the spindle.
The spindle water sealing device for a hydraulic machine according to claim 1, wherein the first seal pressing portion presses the first holding member against the first fixing member toward the first rotation side seal member. The spindle water sealing device for a hydraulic machine according to claim 2, wherein the first seal pressing portion can adjust the surface pressure of the first seal surface. The first seal pressing portion is above the rod attached to the first holding member, extending in the axial direction and penetrating the first fixing member, and the first fixing member attached to the rod. The spindle water sealing device for a hydraulic machine according to claim 3, further comprising a located first receiving portion and an urging member interposed between the first receiving portion and the first fixing member. The second fixing member fixed to the upper cover and
A second holding member that can move in the axial direction with respect to the second fixing member,
A second seal pressing portion that exerts a pressing force on the second sealing surface is provided.
The second seal portion includes a second stationary side seal member held by the second holding member and a second rotation side seal member held by the spindle.
The hydraulic machine according to any one of claims 1 to 4, wherein the second seal pressing portion presses the second holding member against the second fixing member toward the second rotation side seal member. Main shaft water sealing device. The hydraulic power according to any one of claims 1 to 5, wherein the pressurized water supply unit pressurizes the working water in a suction pipe provided on the downstream side of the runner and supplies the pressurized water to the pressurizing chamber. Machine spindle water sealing device. The spindle water sealing device for a hydraulic machine according to any one of claims 1 to 6, wherein the pressurized water supply unit includes a strainer for removing foreign substances in the pressurized water. The spindle water sealing device for a hydraulic machine according to any one of claims 1 to 7, further comprising an exhaust unit for discharging gas in the inlet chamber to the outside. With Lanna,
The spindle connected to the runner and
The upper cover located above the runner and
A hydraulic machine comprising the spindle water sealing device of the hydraulic machine according to any one of claims 1 to 8.

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