JP2000110699A - Non-water feed type seal water device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To completely prevent water from supplying to a seal water chamber by arranging an annular seal member on a rotary seal ring and a static seal ring so as to face to a side of a space where a radial direction inner circumferential edge of an abutting part of the annular seal member is communicated with an inside of a casing, or so as to face to a side of a space where a radial direction outer peripheral edge is communicated with an outside air. SOLUTION: When a main shaft 2 is rotated, an annular seal member 54 is rotated through a rotary seal ring 52a while being brought into slide contact with a separate annular seal member 55. In this time, in slide contact parts of both annular seal members 54, 55, inner and outer circumferential edge sides are filled with water at all times, and lubricating performance is improved. When a lower space 51a of a seal water chamber 50 is lower than the atmospheric pressure, a condition in which intake is easily carried out from a slide contact surfaces of both annular seal members 54, 55 is generated. However, pressure of water which exists on the slide contact part of both annular seal members 54, 55 and a communicating space in a hydraulic turbine in the inner circumferential edge is increased, and it is suppressed that air is invaded to an inner circumferential edge through the slide contact parts of both annular seal members 54, 55, and thereby, intake to a hydraulic turbine can be prevented.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a non-water supply type water sealing device for a water turbine or a pump, and even if the pressure in the water sealing chamber becomes lower than the atmospheric pressure, no water is supplied from the outside. The present invention relates to a non-water supply type water sealing device that can shut off intake air.

[0002]

2. Description of the Related Art First, an outline of a water turbine will be described by taking a vertical axis Francis turbine as an example. FIG. 4 shows a sectional view of the vertical Francis turbine. A main shaft 2 is inserted in the vertical direction of the center of a horizontal spiral-shaped casing 1, and a plurality of blades, which flow down a hydraulic pipe and rotate by water introduced into the casing 1, are provided at a lower end thereof in a circumferential direction. A plurality of guide vanes 4 for adjusting the amount of water to the runner 3 and guiding the flow of water are arranged around the runner 3 in the circumferential direction. I have.

Further, a waterless type water sealing device 5 is provided around a position where the main shaft 2 penetrates the casing 1.
The non-water-supply type water sealing device 5 has a water sealing chamber 50 provided with a gap so that the lower surface communicates with the inside of the casing 1 so as to communicate from the upper surface to the outside air, and is provided inside thereof. The non-water supply type water sealing device 5 has a function of suppressing water leakage from the penetration portion to the outside and a function of shutting off intake air from the outside when the pressure in the water sealing device becomes lower than the atmospheric pressure.

[0004] The non-water-supply type water-sealing device 5 includes a water-sealing chamber 50 formed by a water-sealing case 1 a integral with the casing 1.
And an annular seal member 54 provided via a rotary seal ring 52 integral with the main shaft 2 and an annular seal member 55 provided via a stationary seal ring 53 integral with the water sealing case 1a. The annular seal members 54 and 55 are fixed such that opposing surfaces thereof abut against each other and slide. Further, the annular sealing member 5
4, 55 are arranged so that the inner peripheral edge of the contact portion is located on the side of the space that communicates with the outside air, and the outer peripheral edge of the contact portion is located on the side of the space that communicates with the inside of the water turbine. 54 is disposed with respect to the annular seal member 55 so as to be located inside the water wheel.

The fact that the annular sealing members 54 and 55 are displaced in the radial direction depends on the fixing means, and does not relate to the root of the sealing performance. Further, the annular seal members 54 and 55 are made of a material having extremely high wear resistance to water containing earth and sand, for example, silicon carbide Si.
It is made of ceramic such as C.

In the following, the operation will be described. The water that has flowed down the hydraulic pipe at the time of startup is introduced from the entire circumference of the casing 1, flows toward the main shaft 2, passes through the guide vanes 4, and enters the runner 3. After that, the water changes its flow direction from horizontal inward to downward, applies its pressure and kinetic energy to the runner 3, and falls into the suction pipe while rotating the runner 3, and is discharged to the discharge pond.

During this time, the water that has entered the lower space 51a of the water sealing chamber 50 from inside the casing 1 is guided toward the abutting portions of the two annular seal members 54 and 55 whose opposing surfaces are in close contact with each other. For this reason, the annular seal members 54 and 55 come into contact with the invading water, improve lubricity, and slide smoothly,
Water is sealed by preventing the intruded water from flowing into the inner peripheral direction of the contact portion, that is, the upper space 51b of the water sealing chamber 50. Moreover, since the annular seal members 54 and 55 are made of a material having extremely high wear resistance to water containing earth and sand, even if earth and sand may be bitten, the wear caused by the earth and sand is extremely small. For this reason, the intrusion of water containing earth and sand does not hinder operation, maintenance, and the like.
It is not necessary to provide a means for filtering water that enters the lower space 51a of the water sealing chamber 50 from inside.

[0008]

However, the pressure in the lower space 51a of the water sealing chamber 50 is lower than that in the upper space 51b of the water sealing chamber 50 during a low load operation, for example, at the time of starting, stopping, or the like, for some reason. When the air is sucked into the inside, the water sealing chamber 50 runs out of water, the annular seal members 54 and 55 are dried, the lubricity is lost, the abrasion resistance is increased, and heat is generated.
The problem of wear or damage will occur,
In this case, water needs to be supplied to the contact surfaces of the annular seal members 54 and 55 by the water supply pipe, and the complete abolition of the water supply has not yet been realized.

Accordingly, an object of the present invention is to provide a non-water-supply type water sealing device which can solve the drawbacks of the conventional non-water-supply type water-sealing device and can achieve complete non-water supply to the water sealing chamber. Is to do.

[0010]

DISCLOSURE OF THE INVENTION The present invention has been made to achieve the above object, and a first aspect of the present invention is to provide a water turbine or a pump having a main shaft penetrating as a water sealing means. A water sealing chamber is provided around the main shaft of the casing to be mounted, and annular seal members made of wear-resistant materials are installed between the rotating seal ring provided on the main shaft and the stationary seal ring provided on the casing in the water chamber. In the non-water-supply type water sealing device for contacting and sealing water with each other, a radially inner peripheral edge of a contact portion of the annular seal member is provided on a space side communicating with the inside of the casing, and a radially outer peripheral edge. Wherein the annular seal member is disposed on a rotating seal ring and a stationary seal ring, respectively, such that the annular seal member faces a space that communicates with the outside air.

A second aspect of the present invention is characterized in that, in addition to the configuration of the first aspect, a main shaft is provided on the inner peripheral side of the contact portion of the annular seal member and inside the rotary seal ring. A water holding portion for supplying water to the contact portion of the annular seal member by rotation is provided.

A third aspect of the present invention is characterized in that, in addition to the configuration of the first aspect, a main shaft is provided on the inner peripheral side of the contact portion of the annular seal member and inside the rotary seal ring. There is provided a pump mechanism for supplying the water inside the water wheel or the pump by rotation to increase the pressure toward the inner peripheral edge of the contact portion of the annular seal member.

[0013]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A first embodiment of the present invention is shown in FIG. The non-water supply type water sealing device 5a according to the present invention is provided at a position where the main shaft 2 penetrates the casing 1 as in the related art, and is applicable to any water turbine or pump. The overall configuration, operation, and the like of the water turbine and the like are as described above.

FIG. 1 is a sectional view of a waterless type water sealing device 5a according to the present invention. The non-water supply type water sealing device 5a includes a water sealing chamber 50 formed by a water sealing case 1a integrated with the casing 1, and a rotary seal ring 52a integrated with the main shaft 2.
, And an annular seal member 55 installed via a stationary seal ring 53a integrated with the water sealing case 1a. Opposing surfaces of the annular seal members 54, 55 Are fixed so as to abut against each other and slide.

Further, the annular sealing members 54, 55
Is on the side of the space where the inner peripheral edge of the contact part leads to the inside of the turbine,
The outer peripheral edge of the contact portion is disposed so as to be located on the side of the space that communicates with the outside air, and the annular seal member 55 is provided.
Is disposed with respect to the annular seal member 54 so as to be located inside the water wheel.

The annular seal members 54, 55 are arranged with a cushion sheet (not shown) for cushioning impact between the seal rings 52a, 53a, respectively. It is fixed by a holding member. Further, the annular seal members 54 and 55
Is shifted in the radial direction, depends on the fixing means, and does not relate to the root of the sealing performance. Further, the annular seal members 54 and 55 are both made of a material having extremely high wear resistance to water containing earth and sand, for example, a ceramic such as silicon carbide SiC.

In the first embodiment, in addition to the above-described structure, the annular shaft is rotated by the rotation of the main shaft 2 on the inner peripheral side of the contact portion between the annular seal members 54 and 55 and inside the rotary seal ring 52a. A water receiving container is provided as a water holding unit 60 that supplies water to the contact portions of the seal members 54 and 55.

The operation will be described below.
With the rotation of the main shaft 2, the annular seal member 54 contacts the annular seal member 55 via the rotary seal ring 52a,
It rotates while sliding. At this time, the annular seal member 54,
The contact portion 55 is always filled with water on both the inner peripheral side and the outer peripheral side, so that the lubricating properties of the contact surfaces are increased, so that there is no wear or damage due to frictional resistance or heat generation, and water leakage occurs. Alternatively, intake can be prevented. Further, even if earth and sand are contained in the water, the annular seal members 54 and 55 are extremely excellent in abrasion resistance.

On the other hand, the lower space 51a of the water sealing chamber 50 may be lower than the atmospheric pressure at the time of other low load during start-up or stop. In this case, the air is sucked from the contact surfaces of the annular seal members 54 and 55. However, the water existing in the space between the abutting portions of the two annular seal members 54 and 55 and the inner peripheral edge of the water turbine is subjected to centrifugal force due to the rotation of the annular seal member 54, and Is increased, and the intrusion of air from the outer peripheral edge to the inner peripheral edge via the abutting portions of the two seal members 54 and 55 can be suppressed, so that intake into the water turbine is prevented.

Therefore, according to the above-described embodiment, even when the load is low, the friction caused by running out of the water at the contact portions of the two seal members 54 and 55 does not depend on the forced water supply to the water sealing chamber 50 by the water supply pipe or the like. Accidents such as an increase in resistance and wear or damage due to heat generation can be prevented, and the burden on equipment and maintenance is significantly reduced. In addition, the water holding part 60 which rotates integrally with the rotary seal ring 52a holds water, and the held water is used for the two seal rings 52a, 53.
Through the interval a, the supply is made toward the inner peripheral edge of the portion where the annular seal members 54 and 55 come into contact, so that the intake prevention effect can be further increased.

FIG. 2 shows a second embodiment. This embodiment replaces the water holding portion 60 in the first embodiment with a screw seal, a blade, and the like, in order to send water inside the water turbine toward the inner peripheral edge of the contact portion of the annular seal members 54 and 55. This is provided with a pump mechanism 70 made of other components.

According to the second embodiment, the water inside the turbine connected to the lower space 51a of the water sealing chamber 50 is boosted by the pump mechanism 70 toward the inner peripheral edge of the contact portion between the annular seal members 54 and 55. Therefore, the pressure of water can be increased more than the supply of water to the inner peripheral edge of the abutting portion of the annular seal members 54 and 55 by the water holding portion 60, so that the effect of preventing intake can be further improved. . Other effects are
This is the same as that according to the first embodiment.

[0023]

As described above, by using the first aspect of the present invention, the pressure in the lower space of the water sealing chamber rises above the water sealing chamber at the time of starting or stopping, or during other low-load operation. Even if the pressure is lower than the pressure of the space and a state where air is easily sucked from the abutting surface of the annular seal member occurs, water existing in the abutting portion of the two annular seal members and the space communicating with the inside of the turbine at the inner peripheral edge thereof is removed. Because of the centrifugal force caused by the rotation of the annular seal member, the pressure of the water rises, and it is possible to suppress the intrusion of air from the outer peripheral edge to the inner peripheral edge through the contact portion between the two annular seal members. The intake to the inside can be prevented.
Therefore, even when the load is low, the frictional resistance increases due to running out of water at the abutting portions of the two annular seal members, and friction or damage due to heat is generated without depending on forced water supply to the water sealing chamber by a water supply pipe or the like. Accidents can be prevented, and the burden on equipment and maintenance can be significantly reduced.

Further, by using the invention described in claim 2, in addition to the effect of the invention described in claim 1, the water holding portion which rotates integrally with the rotary seal ring holds water, and this water is held. Since the water is supplied between the two seal rings and toward the inner peripheral edge of the portion where the annular seal member abuts, the intake prevention effect can be further increased.

Further, by using the invention of claim 3, in addition to the effect of the invention of claim 1, in addition to the effect of the invention of claim 1, the water inside the turbine connected to the water sealing chamber is brought into contact with the annular seal member by the pump mechanism. Because the pressure is increased toward the inner peripheral edge and the water is sent,
Since the pressure of the water supplied to the inner peripheral edge of the abutting portion of the annular seal member can be increased, the effect of preventing intake air can be further improved.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view showing a non-water supply type water sealing device according to a first embodiment of the present invention.

FIG. 2 is a sectional view showing a non-water-supply type water sealing device according to a second embodiment of the present invention.

FIG. 3 is a sectional view showing a conventional water sealing device.

FIG. 4 is a sectional view of a vertical Francis turbine.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Casing 2 Main shaft 3 Runner 4 Guide vane 5 Non-water supply type water sealing device 5a Non-water supply type water sealing device 50 Water sealing room 51a Space under a water sealing room 51b Space above a water sealing room 52 Rotary seal ring 52a Rotary seal ring 53 Stationary seal ring 53a Stationary seal ring 54 Annular seal member 55 Annular seal member 60 Water holding part 70 Pump mechanism A Outside air B Inside the casing

Claims (3)

[Claims] A water sealing means is provided around a main shaft of a casing through which a main shaft penetrates as a water sealing means of a water wheel or a pump, and a rotary seal ring provided on the main shaft in the enclosed water chamber and a stationary seal ring provided on the casing. In the non-water-supply type water sealing device in which annular seal members each made of a wear-resistant material are installed between them, and they are brought into contact with each other to seal water, the radial inner peripheral edge of the contact portion of the annular seal member is provided. Wherein the annular seal member is disposed on the rotating seal ring and the stationary seal ring, respectively, such that the annular seal member faces the space side communicating with the inside of the casing and the radially outer peripheral edge faces the space side communicating with the outside air. Water supply type water sealing device. 2. A water holding portion for supplying water to the contact portion of the annular seal member by rotation of a main shaft on the inner peripheral side of the contact portion of the annular seal member and inside the rotary seal ring. The non-water-supply type water sealing device according to claim 1, wherein the water sealing device is provided. 3. An inner peripheral side of an abutting portion of the annular seal member and inside of the rotary seal ring, water inside a water turbine or a pump is rotated by rotation of a main shaft, and a contact portion of the annular seal member is provided. 2. The non-water-supply type water sealing device according to claim 1, further comprising a pump mechanism for increasing the pressure toward an inner peripheral edge of the water supply device.