Floating ball type vacuum breaker valve for water turbine

Abstract

The utility model discloses a floating ball type vacuum breaking valve for a water turbine, which relates to the technical field of water turbines and comprises a tubular valve body pipe, a partition plate arranged in the valve body pipe, an air supplementing hole arranged on the partition plate and a floating ball arranged on the lower side of the air supplementing hole and used for blocking the air supplementing hole. The lower end of the upper valve body pipe is connected with the upper end of the lower valve body pipe in a welding or flange mode, and the partition plate is welded to the lower end of the upper valve body pipe or the upper end of the lower valve body pipe. The structural design of the vacuum breaking valve can effectively guarantee the sealing reliability of the floating ball.

Description

TECHNICAL FIELD

[0001] The utility model relates to the technical field of water turbine, especially a floating ball type vacuum breaking valve for water turbine. BACKGROUND

[0002] The vacuum breaking valve (also commonly known as air supplement valve, air valve) is an important safety device on the water turbine, mainly used for preventing the runner chamber or draft tube from forming a vacuum under the working conditions of emergency shutdown of the water turbine, rapid closure of the guide vane and the like, avoiding air cavitation, structural deformation or water hammer impact and the like, and having the effect of protecting the water turbine system.

[0003] In the prior art, the vacuum breaking valves widely used on the water turbine include floating ball type vacuum breaking valves and spring type vacuum breaking valves, and the differences and characteristics of the two include: due to the size, only the floating ball type vacuum breaking valve is suitable for double valve use; the fluid flow in the floating ball type vacuum breaking valve is stable, and no large noise and vibration are generated during air supplement; the pressure loss generated by the floating ball type vacuum breaking valve is very small; the spring type vacuum breaking valve has a high risk of jamming during operation, and even the problem of damaging the valve body structure occurs after jamming, based on the above, on the small and medium-sized water turbine, the floating ball type vacuum breaking valve is a commonly used vacuum breaking valve.

[0004] The working principle of the floating ball type vacuum breaking valve is that the ball on the valve relies on gravity to rise and fall with the water level, achieving the purpose of controlling the opening and closing of the air supplement hole on the valve, for example, when a vacuum is formed, the pressure difference pushes the floating ball to fall, the air supplement hole is connected to make the valve in an open state, and when the water level recovers, the floating ball floats up and cooperates with the sealing ring at the position of the air supplement hole, and the valve returns to a closed state. In the working process of the floating ball type vacuum breaking valve, the lifting of the floating ball depends on the comprehensive result of gravity and buoyancy, and the vertical installation (perpendicular direction, such as connection with the vertical section structure of the draft tube or pressure balance pipe of the water turbine) can ensure smooth movement of the floating ball in the vertical direction, avoid jamming or delay caused by inclination, and therefore in specific application, the optimal installation mode of the floating ball type vacuum breaking valve is vertical installation, so as to ensure the functional reliability and response speed.

[0005] Under the above use method, the common problems of the floating ball type vacuum breaking valve include sealing failure of the sealing ring at the position of the air supplement hole due to aging, wear and tear and the like, in order to ensure the service life of the vacuum breaking valve, the existing technical solutions include selection of sealing ring material and adjustment of sealing ring structure, and through retrieval, the specific technical solutions are provided in the patent application No.

[0006] Further optimizing the structure of the floating ball type vacuum breaking valve is an important measure to reduce the operation failure rate of the water turbine and improve the operation efficiency of the water turbine. UTILITY MODEL CONTENT

[0007] In view of the above-mentioned problems of the optimized structure of the floating ball type vacuum breaking valve, the utility model provides a floating ball type vacuum breaking valve for a water turbine, and the structural design of the vacuum breaking valve can effectively guarantee the sealing reliability of the floating ball.

[0008] In view of the above-mentioned problems, the floating ball type vacuum breaking valve for a water turbine provided by the utility model solves the problems through the following technical points: the floating ball type vacuum breaking valve for a water turbine comprises a tubular valve body pipe, a partition plate arranged in the valve body pipe, a gas supplement hole arranged on the partition plate, and a floating ball arranged below the gas supplement hole and used for plugging the gas supplement hole, the valve body pipe comprises an upper valve body pipe and a lower valve body pipe, the lower end of the upper valve body pipe is welded or flange connected with the upper end of the lower valve body pipe, and the partition plate is welded to the lower end of the upper valve body pipe or the upper end of the lower valve body pipe.

[0009] In the prior art, the floating ball in the floating ball type vacuum breaking valve for a water turbine is constrained in a guide space of a shell, that is, the valve body pipe, the side boundary of the guide space comprises but is not limited to a guide screw as the boundary, and the top side and the bottom side of the guide space are respectively provided with an upper stop ring and a lower stop ring, the upper stop ring is the sealing ring, the lower stop ring comprises but is not limited to the first support ring provided below, and the floating ball type vacuum breaking valve is usually vertically installed in a pipeline, the ideal installation state is that the axis direction of the gas supplement hole is in the vertical direction, and the floating ball moves in the vertical direction in the small radial gap of the guide space. In the prior art, the position of the partition plate is usually located at the middle upper end of the valve body pipe (in the valve body pipe with a floating body and a spring type plugging structure, the position of the partition plate is arranged at the middle lower section of the valve body pipe), so that the connection position of the partition plate in the valve body pipe is usually located inside the valve body pipe and between the two ends of the valve body pipe, and the connection mode of the partition plate and the valve body pipe is usually welding connection. The position of the partition plate in the valve body pipe has the problems that when the partition plate is welded, it is difficult to control the perpendicularity of the partition plate and the valve body pipe, it is difficult to guarantee the perpendicularity precision, when the partition plate is inclined relative to the valve body pipe, the sealing ring arranged at the lower end of the partition plate is synchronously inclined with the partition plate, and the problems that may be caused include that there is a large difference in the contact force of each point on the sealing surface of the sealing ring in the circumferential direction of the floating body after the floating body freely floats, and under the condition that the sealing ring is aged to a certain degree and the sealing surface is attached with silt, the floating body cannot reliably plug the gas supplement hole after floating, and the vacuum breaking valve is prone to leakage.

[0010] In the scheme, the valve body pipe is provided with an upper valve body pipe and a lower valve body pipe, and the upper valve body pipe and the lower valve body pipe are connected by welding or flange connection to form a connection relationship, and a partition plate is further welded at the lower end of the upper valve body pipe or the upper end of the lower valve body pipe. In the preparation of the vacuum breaking valve, the connection of the partition plate on the upper valve body pipe or the lower valve body pipe is completed first, and then the series connection of the upper valve body pipe and the lower valve body pipe is completed. Since the partition plate is located at the end of the upper valve body pipe or the lower valve body pipe during welding, the partition plate can be efficiently welded and perpendicular to the axis of the upper valve body pipe and the lower valve body pipe from the aspects of welding operation convenience and partition plate verticality adjustment convenience. Therefore, the scheme can ensure the verticality of the partition plate and the valve body pipe from the installation precision of the partition plate, and achieve the purpose of reliably sealing the air inlet hole by the sealing ring when the floating ball passes through the air inlet hole.

[0011] In specific implementation, the outer edge of the partition plate is provided with an annular cutout, and the partition plate is welded to the lower end of the upper valve body pipe (the annular cutout is located on the outer edge of the lower end) or the upper end of the lower valve body pipe (the annular cutout is located on the outer edge of the upper end). Since the partition plate is installed once and can be maintained free of maintenance in the later period, the upper valve body pipe and the lower valve body pipe are connected by welding, and an annular welding seam is formed at the outer periphery of the valve body pipe.

[0012] As a further technical scheme of the floating ball type vacuum breaking valve,

[0013] Further comprising a plurality of guide screws connected to the partition plate and arranged at intervals in the circumferential direction of the air inlet hole, the upper end of the guide screw being connected to the partition plate, the partition plate being provided with a sealing ring located on the bottom side of the partition plate, the sealing ring serving as a sealing structure between the floating ball and the air inlet hole;

[0014] Further comprising a first support ring connected to the lower end of the guide screw, the first support ring being a flexible ring, and the floating ball being constrained in the space surrounded by the guide screw and located between the sealing ring and the first support ring.

[0015] The above provides a technical scheme of using a guide screw as a guide rod to surround the guide space, and setting a locking nut connected to the upper end of the guide screw as a lower stop ring below the floating ball. Specifically, based on the guide screw, a locking nut can be connected and locked by a thread connected to the upper end of the guide screw, and the upper end of the locking nut can provide pressure to the outer edge of the bottom side of the sealing ring to fix the sealing ring at the lower end of the partition plate and form a static sealing surface. When the floating ball forms a sealing fit with the hole of the sealing ring under the buoyancy, the sealing of the air inlet hole is achieved. The sealing ring is usually a rubber ring, and the first support ring can also be a flexible ring. Therefore, when the floating ball rises and falls, the impact with the sealing ring and the first support ring is a flexible impact, which can achieve the purpose of protecting the outer surface of the floating ball.

[0016] The upper end surface of the sealing ring is provided with an annular groove coaxial with the sealing ring, and further comprises a second supporting ring embedded in the annular groove and located at the bottom side of the annular groove;

[0017] A plurality of compression springs are arranged between the partition plate and the second supporting ring, and the compression springs are arranged in the circumferential direction of the second supporting ring.

[0018] The lower end of the sealing ring has a spherical surface for cooperating with the floating ball, and the lower end of the second supporting ring faces the spherical surface.

[0019] When the floating ball is separated from the sealing ring, the compression springs are in an elastic compression state or a free elongation state.

[0020] In the above scheme, the annular groove is used to accommodate the second supporting ring and the compression springs, and is arranged such that the compression springs can provide a relatively uniform elastic force in the circumferential direction of the second supporting ring, and the vertical downward projection of the second supporting ring is located on the spherical surface of the sealing ring for cooperating with the floating ball. In this way, when the sealing ring is pressed by the floating ball under the buoyancy of the floating ball, the sealing ring is elastically compressed and deformed, at this time, the second supporting ring moves upward under the upward thrust of the sealing ring, and the compression springs are elastically deformed or further elastically deformed. By using the above structure, the high elastic limit and strong fatigue resistance of the compression springs can be utilized to compensate for the problem that the sealing ring made of rubber is prone to fatigue and aging after being deformed multiple times, that is, the service life of the sealing ring can be effectively prolonged by using the compression springs. In addition, the second supporting ring can uniformly transmit the elastic force of the compression springs to the sealing ring, and when the floating ball and the spherical surface of the sealing ring are in close contact, each position of the sealing ring in the circumferential direction has a relatively uniform contact force with the floating ball to ensure the sealing effect. In addition, compared with filling the compression springs in the sealing ring / direct contact between the lower end of the compression spring and the sealing ring, the above structure can effectively prevent the position of the sealing ring for contacting the compression spring from cracking and failing.

[0021] As a person skilled in the art, the above setting of the lower end of the second supporting ring facing the spherical surface is used to realize that when the floating ball presses the sealing ring, the compression springs can be compressed or further compressed to maintain the elastic performance of the sealing ring to the floating ball, so as to protect the floating ball. When the spherical surface is aging, the sealing ring should be replaced in time to ensure the sealing effect. The state of the floating ball and the sealing ring being separated is a state in which the sealing ring is not loaded by the floating ball, that is, at this time, the floating ball does not affect the length of the compression spring in this state.

[0022] Each compression spring is fitted with a separate spring groove at the lower end of the partition plate, and the upper end of each compression spring is embedded in the spring groove fitted therewith.

[0023] In the above scheme, the spring groove is used to limit the position of the upper end of each compression spring on the partition plate, so as to limit the position of the compression spring in the circumferential direction of the second supporting ring.

[0024] The through groove is connected with the ring groove at the inner side and is located outside the sealing ring at the outer side.

[0025] In the above scheme, the ring groove is connected with the internal space of the valve body pipe through the through groove, and the through groove is designed to avoid the ring groove from forming a closed cavity to affect the deformation of the sealing ring when the compression spring is compressed under the action of the floating ball. The position of the outer side of the through groove is such that the outer side of the through groove is located in the non-main water flow area of the valve body pipe, so as to reduce the possibility of silt blocking the through groove.

[0026] The filter screen is filled in the through groove.

[0027] The number of the through grooves is greater than or equal to 1.

[0028] When the number of the through grooves is greater than 1, the through grooves are arranged at intervals in the circumferential direction of the ring groove, and each through groove is provided with a filter screen.

[0029] In the above scheme, the filter screen is used to prevent silt from entering the setting area of the compression spring, so as to avoid jamming or damage of the compression spring during movement. The number of the through grooves is preferably greater than 1, which is used to ensure the reliability of the connection between the ring groove and the outside. When the number of the through grooves is greater than 1, they are preferably evenly distributed relative to the axis of the ring groove. The position of the through grooves is limited so that the ring groove can be relieved or pressurized through multiple points, thereby ensuring the consistency of the deformation of the sealing ring at each position in the circumferential direction.

[0030] The support plate is further provided, the first support ring is supported on the support plate, and the laminated structure formed by the first support ring and the support plate is locked on the lower end of the guide screw by the locking nut. Each guide screw is provided with a locking nut for locking the laminated structure.

[0031] The above scheme provides a technical scheme for fixing the position of the first support ring in the guide space based on the guide screw, the support plate and the locking nut. The guide space is a stable space by using the rigid structure of the partition plate and the support plate.

[0032] The annular pressing plate is further provided, the upper end of the sealing ring is attached to the bottom surface of the partition plate, and the lower end of the sealing ring is supported on the pressing plate.

[0033] The screw hole through which the guide screw passes through the pressing plate is matched on the pressing plate, each guide screw is provided with a separate screw hole, each guide screw passes through the pressing plate through the screw hole, and the pressing plate is slidable relative to the guide screw.

[0034] The laminated structure formed by the pressing plate and the sealing ring is locked on the guide screw by the locking nut, and each guide screw is provided with a locking nut for locking the laminated structure.

[0035] In the above scheme, the sealing ring is fixed to the lower end of the partition plate by means of the guide screw, the pressing plate and the locking nut, so as to fix the sealing ring to the lower end of the partition plate and form the static sealing surface. In this scheme, the upper end of the locking nut provides uniform upward thrust to the outer edge of the lower end of the sealing ring through the pressing plate, so as to fix the sealing ring and obtain the static sealing surface.

[0036] Each guide screw is sleeved with a flexible sleeve.

[0037] In the above scheme, the flexible sleeve is used to form a flexible support layer on the outer side of the guide screw, so as to provide flexible protection for the floating ball when the floating ball moves radially and collides with the guide screw, thereby achieving the purpose of protecting the surface of the floating ball.

[0038] The floating ball comprises a hollow steel ball and a polytetrafluoroethylene surface layer wrapped outside the hollow steel ball.

[0039] In the above scheme, the hollow steel ball is used to ensure the shape stability of the floating ball, and the polytetrafluoroethylene surface layer is used to reduce the possibility of sediment deposition on the surface of the floating ball, thereby reducing the influence of the sediment on the service life of the sealing ring and the influence on the sealing reliability of the air inlet hole.

[0040] The utility model has the following beneficial effects:

[0041] In this scheme, the partition plate is located at the end of the upper valve body pipe or the lower valve body pipe, so that efficient welding of the partition plate and perpendicularity of the partition plate to the axis of the upper valve body pipe and the lower valve body pipe can be achieved from the aspects of convenience of welding operation and convenience of adjustment of perpendicularity of the partition plate, and the perpendicularity of the partition plate to the valve body pipe can be ensured from the aspect of installation precision of the partition plate on the valve body pipe. When the vacuum breaking valve is vertically installed on the pipeline, the floating ball can reliably seal the air inlet hole through the sealing ring. BRIEF DESCRIPTION OF DRAWINGS

[0042] Figure 1 A sectional view of one specific embodiment of the floating ball type vacuum breaking valve for a hydraulic turbine according to the present scheme;

[0043] Figure 2 A sectional view of one specific embodiment of the floating ball type vacuum breaking valve for a hydraulic turbine according to the present scheme; Figure 1 A local enlarged view of part A.

[0044] The reference signs in the drawings are as follows: 1, upper valve body pipe; 2, partition plate; 3, sealing ring; 4, guide screw; 5, flexible sleeve; 6, first support ring; 7, support plate; 8, floating ball; 9, air inlet hole; 10, filter screen; 11, through groove; 12, second support ring; 13, compression spring; 14, pressing plate; 15, lower valve body pipe. DETAILED DESCRIPTION

[0045] The utility model will be further explained in detail in combination with the embodiments below, but the utility model is not limited to the following embodiments.

[0046] Embodiment 1:

[0047] As shown in Figure 1 and Figure 2 The ball float type vacuum breaking valve for the water turbine includes a tubular valve body pipe, a partition plate 2 arranged in the valve body pipe, a gas supplement hole 9 arranged on the partition plate 2, and a ball float 8 arranged at the lower side of the gas supplement hole 9 and used for plugging the gas supplement hole 9. The valve body pipe includes an upper valve body pipe 1 and a lower valve body pipe 15. The lower end of the upper valve body pipe 1 is welded or flange-connected with the upper end of the lower valve body pipe 15. The partition plate 2 is welded to the lower end of the upper valve body pipe 1 or the upper end of the lower valve body pipe 15.

[0048] In the prior art, the ball float 8 in the ball float type vacuum breaking valve for the water turbine is constrained in a guide space of a shell, that is, the valve body pipe. The side boundary of the guide space includes but is not limited to a guide screw 4. The top side and the bottom side of the guide space are respectively provided with an upper stop ring and a lower stop ring. The upper stop ring is the sealing ring 3. The lower stop ring includes but is not limited to a first support ring 6. At the same time, the ball float type vacuum breaking valve is usually vertically installed in a pipeline. The ideal installation state is that the axis direction of the gas supplement hole 9 is in the vertical direction, and the ball float 8 moves in the vertical direction in the small radial gap of the guide space. In the existing valve body pipe, the position of the partition plate 2 is usually located at the middle upper end of the valve body pipe (in the valve body pipe with a floating body and a spring type plugging structure, the position of the partition plate 2 is arranged at the middle lower section of the valve body pipe). In this way, the connection position of the partition plate 2 in the valve body pipe is usually located inside the valve body pipe and between the two ends of the valve body pipe. The connection mode of the partition plate 2 and the valve body pipe is usually welding connection. The position of the partition plate 2 in the valve body pipe has the problems that when the partition plate 2 is welded, the perpendicularity control of the partition plate 2 and the valve body pipe is difficult, and it is difficult to guarantee the perpendicularity precision. When the partition plate 2 is inclined relative to the valve body pipe, the sealing ring 3 arranged at the lower end of the partition plate 2 is synchronously inclined with the partition plate 2. This may cause the problems that the contact force of each point on the sealing surface of the sealing ring 3 in the circumferential direction of the floating body after the floating body freely floats is greatly different. In the case that the sealing ring 3 is aged to a certain degree and the sealing surface is attached with silt, the floating body after floating can not reliably plug the gas supplement hole 9, and the vacuum breaking valve may leak.

[0049] In the scheme, the valve body pipe is provided with the upper valve body pipe 1 and the lower valve body pipe 15, and the upper valve body pipe 1 and the lower valve body pipe 15 are connected by welding or flange connection to form a connection relationship, and the partition plate 2 is further welded at the lower end of the upper valve body pipe 1 or the upper end of the lower valve body pipe 15. In this way, when the vacuum breaking valve is prepared, the connection of the partition plate 2 on the upper valve body pipe 1 or the lower valve body pipe 15 is completed first, and then the series connection of the upper valve body pipe 1 and the lower valve body pipe 15 is completed. Since the partition plate 2 is located at the end of the upper valve body pipe 1 or the lower valve body pipe 15 when the partition plate 2 is welded, the efficient welding of the partition plate 2 and the welding of the partition plate 2 perpendicular to the axis of the upper valve body pipe 1 and the lower valve body pipe 15 can be realized from the aspects of welding operation convenience and partition plate 2 verticality adjustment convenience. Therefore, the scheme can ensure the perpendicularity of the partition plate 2 and the valve body pipe from the installation precision of the partition plate 2 on the valve body pipe, and achieve the purpose of reliably sealing the air hole 9 by the sealing ring 3 when the float ball 8 passes through the air hole 9 in use.

[0050] In specific implementation, the outer edge of the partition plate 2 is provided with an annular cutout, and the partition plate 2 is welded to the lower end of the upper valve body pipe 1 (the annular cutout is located on the outer edge of the lower end) or the upper end of the lower valve body pipe 15 (the annular cutout is located on the outer edge of the upper end). Since the partition plate 2 is installed once and then maintained free of maintenance, the upper valve body pipe 1 and the lower valve body pipe 15 are connected by welding, and an annular welding seam is formed at the outer periphery of the valve body pipe.

[0051] Embodiment 2:

[0052] This embodiment is further refined on the basis of Embodiment 1:

[0053] Further comprising a plurality of guide screws 4 connected to the partition plate 2 and arranged at intervals in the circumferential direction of the air hole 9, the upper end of the guide screw 4 being connected to the partition plate 2, the partition plate 2 being provided with a sealing ring 3 located at the bottom side of the partition plate 2, the sealing ring 3 serving as a sealing structure between the float ball 8 and the air hole 9;

[0054] Further comprising a first support ring 6 connected to the lower end of the guide screw 4, the first support ring 6 being a flexible ring, and the float ball 8 being constrained in the space surrounded by the guide screw 4 and located between the sealing ring 3 and the first support ring 6.

[0055] The above provides a technical scheme of taking the guide screw 4 as a guide rod enclosing the guide space, and setting a lower stop ring below the floating ball 8 at the lower end of the guide screw 4. Specifically, based on the guide screw 4, a threaded connecting locking nut can be connected thereon, and the upper end of the locking nut can provide pressure for the outer edge of the bottom side of the sealing ring 3, so as to fix the sealing ring 3 at the lower end of the partition plate 2 and form a static sealing surface. When the floating ball 8 forms a sealing fit surface with the hole of the sealing ring 3 under the buoyancy, the sealing of the air supplement hole 9 is realized. The sealing ring 3 is usually a rubber ring, and the first support ring 6 can also be a flexible ring of rubber ring. In this way, when the floating ball 8 rises and falls, the impact formed with the sealing ring 3 and the first support ring 6 is a flexible impact, which can achieve the purpose of protecting the outer surface of the floating ball 8.

[0056] Embodiment 3:

[0057] This embodiment is further refined on the basis of Embodiment 2:

[0058] The upper end surface of the sealing ring 3 is provided with an annular groove coaxial with the sealing ring 3, and further comprises a second support ring 12 inlaid in the annular groove and located at the bottom side of the annular groove;

[0059] A plurality of compression springs 13 are arranged between the partition plate 2 and the second support ring 12, and the compression springs 13 are arranged in the circumferential direction of the second support ring 12.

[0060] The lower end of the sealing ring 3 has a spherical surface for cooperating with the floating ball 8, and the lower end of the second support ring 12 faces the spherical surface.

[0061] When the floating ball 8 is separated from the sealing ring 3, the compression spring 13 is in an elastic compression state or a free elongation state.

[0062] In the above scheme, the annular groove is used to accommodate the second support ring 12 and the compression spring 13, and is configured such that the compression spring 13 can provide a relatively uniform elastic force in the circumferential direction of the second support ring 12, and the vertical downward projection of the second support ring 12 is located on the spherical surface of the sealing ring 3 for cooperation with the floating ball 8. In this way, when the sealing ring 3 is pressed against the floating ball 8 under the buoyancy of the floating ball 8, the sealing ring 3 is elastically compressed and deformed, at this time, the second support ring 12 moves upward under the upward thrust of the sealing ring 3, and the compression spring 13 is elastically deformed or further elastically deformed. By using the above, the high elastic limit and strong fatigue resistance of the compression spring 13 can be utilized to compensate for the problem that the sealing ring 3 made of rubber is prone to fatigue and aging after being deformed multiple times, that is, the service life of the sealing ring 3 can be effectively prolonged by using the compression spring 13. In addition, the second support ring 12 can uniformly transmit the elastic force of the compression spring 13 to the sealing ring 3, and when the spherical surface of the floating ball 8 is in close contact with the sealing ring 3, the sealing ring 3 has a relatively uniform contact force with the floating ball 8 at each position in the circumferential direction to ensure the sealing effect. In addition, compared with filling the compression spring 13 in the sealing ring 3 / directly contacting the lower end of the compression spring 13 with the sealing ring 3, the above structure can effectively prevent the position on the sealing ring 3 for contacting the compression spring 13 from cracking and failing.

[0063] As a person skilled in the art, the above setting of the direction of the lower end of the second support ring 12 is to achieve that when the floating ball 8 presses the sealing ring 3, the compression spring 13 can be compressed or further compressed to maintain the elastic performance of the sealing ring 3 to the floating ball 8, so as to protect the floating ball 8. When the spherical surface is aging, the sealing ring 3 should be replaced in time to ensure the sealing effect. The state in which the floating ball 8 is separated from the sealing ring 3 is the state in which the sealing ring 3 is not loaded by the floating ball 8, that is, at this time, the length of the compression spring 13 is not affected by the floating ball 8.

[0064] Embodiment 4:

[0065] This embodiment is further refined on the basis of embodiment 3:

[0066] Each compression spring 13 is adapted with a separate spring groove on the lower end of the partition plate 2, and the upper end of each compression spring 13 is embedded in the spring groove adapted thereto.

[0067] In the above scheme, the spring groove is used to limit the position of the upper end of each compression spring 13 on the partition plate 2, so as to limit the position of the compression spring 13 in the circumferential direction of the second support ring 12.

[0068] Embodiment 5:

[0069] This embodiment is further refined on the basis of embodiment 3:

[0070] Further comprising a through groove 11 arranged on the lower end of the partition plate 2, the inner side of the through groove 11 is connected with the ring groove, and the outer side of the through groove 11 is located outside the sealing ring 3.

[0071] In the above scheme, the ring groove is connected with the internal space of the valve body pipe through the through groove 11, and when the compression spring 13 is compressed under the action of the floating ball 8, the through groove 11 is designed to avoid the ring groove forming a closed cavity to affect the deformation of the sealing ring 3, and the position of the outer side of the above through groove 11 is designed to make the outer side of the through groove 11 located in the non-main water flow area of the valve body pipe, so as to reduce the possibility of silt blocking the through groove 11.

[0072] Embodiment 6:

[0073] This embodiment is further refined on the basis of embodiment 5:

[0074] Further comprising a filter screen 10 filled in the through groove 11;

[0075] The number of the through groove 11 is greater than or equal to 1;

[0076] When the number of the through groove 11 is greater than 1, the through grooves 11 are arranged at intervals in the circumferential direction of the ring groove, and each through groove 11 is provided with a filter screen 10.

[0077] In the above scheme, the above filter screen 10 is used to prevent silt from entering the arrangement area of the compression spring 13, so as to avoid the compression spring 13 from being jammed or damaged when it is moving, the number of the through groove 11 is preferably greater than 1, which is used to ensure the reliability of the connection between the ring groove and the outside, and when the number of the through groove 11 is greater than 1, it is preferably evenly distributed relative to the axis of the ring groove, and the position of the through groove 11 is limited so that the ring groove can be relieved or supplemented in multiple points, so as to ensure the consistency of the deformation of the sealing ring 3 at each position in the circumferential direction.

[0078] Embodiment 7:

[0079] This embodiment is further refined on the basis of embodiment 2:

[0080] Further comprising a support plate 7, the first support ring 6 is supported on the support plate 7, and the laminated structure formed by the first support ring 6 and the support plate 7 is locked at the lower end of the guide screw 4 by a locking nut, and each guide screw 4 is provided with a locking nut for locking the laminated structure.

[0081] The above scheme provides a technical scheme for realizing the position fixation of the first support ring 6 in the guide space based on the guide screw 4, the support plate 7 and the locking nut, and uses the partition plate 2 and the support plate 7 which are rigid structures to make the guide space a stable space.

[0082] Embodiment 8:

[0083] The embodiment is further refined based on Embodiment 2:

[0084] The sealing ring 3 is also provided with a ring-shaped pressing plate 14, the upper end of the sealing ring 3 is attached to the bottom surface of the partition plate 2, and the lower end of the sealing ring 3 is supported on the pressing plate 14;

[0085] The pressing plate 14 is provided with a screw hole through which the guide screw 4 passes, each guide screw 4 is provided with a separate screw hole, each guide screw 4 passes through the pressing plate 14 through the screw hole, and the pressing plate 14 is slidable relative to the guide screw 4;

[0086] The laminated structure formed by the pressing plate 14 and the sealing ring 3 is locked on the guide screw 4 by a locking nut, and each guide screw 4 is provided with a locking nut for locking the laminated structure.

[0087] In the above scheme, the sealing ring 3 is fixed at the upper end and attached to the lower end surface of the partition plate 2 to complete the fixation of the sealing ring 3 at the lower end of the partition plate 2 and form the static sealing surface based on the guide screw 4, the pressing plate 14 and the locking nut. In this scheme, the upper end of the locking nut provides uniform upward thrust to the outer edge of the lower end of the sealing ring 3 through the pressing plate 14, achieving the purpose of fixing the sealing ring 3 and obtaining the static sealing surface.

[0088] Embodiment 9:

[0089] The embodiment is further refined based on Embodiment 2:

[0090] Each guide screw 4 is provided with a flexible sleeve 5.

[0091] In the above scheme, the flexible sleeve 5 is used to form a flexible support layer on the outside of the guide screw 4, so that when the floating ball 8 moves radially and collides with the guide screw 4, the flexible sleeve 5 provides flexible protection for the floating ball 8, achieving the purpose of protecting the surface of the floating ball 8.

[0092] Embodiment 10:

[0093] The embodiment is further refined based on Embodiment 1:

[0094] The floating ball 8 includes a hollow steel ball and a polytetrafluoroethylene surface layer wrapped outside the hollow steel ball.

[0095] In the above scheme, the hollow steel ball is used to ensure the shape stability of the floating ball 8, and the polytetrafluoroethylene surface layer is used to reduce the possibility of sediment deposition on the surface of the floating ball 8, reduce the influence of sediment on the service life of the sealing ring 3 and the sealing reliability of the air supply hole 9.

[0096] The above is further detailed description of the utility model in combination with specific preferred embodiments, and cannot be deemed that the specific embodiments of the utility model are limited to these descriptions. For ordinary skilled persons in the technical field of the utility model, other embodiments obtained without departing from the technical solutions of the utility model shall be included in the protection scope of the utility model.

Claims

1. A float-type vacuum breaker valve for a water turbine, comprising a tubular valve body tube, a baffle plate (2) disposed within the valve body tube, an air inlet (9) disposed on the baffle plate (2), and a float (8) disposed below the air inlet (9) for sealing the air inlet (9), characterized in that, The valve body tube includes an upper valve body tube (1) and a lower valve body tube (15). The lower end of the upper valve body tube (1) is welded to the upper end of the lower valve body tube (15) or connected by a flange. The partition (2) is welded to the lower end of the upper valve body tube (1) or the upper end of the lower valve body tube (15).

2. The float-type vacuum breaker valve for a water turbine according to claim 1, characterized in that, It also includes multiple guide screws (4) connected to the partition (2) and arranged at intervals around the air inlet (9) in the circumferential direction. The upper end of the guide screws (4) is connected to the partition (2). A sealing ring (3) is provided on the partition (2) located on the bottom side of the partition (2). The sealing ring (3) serves as a sealing structure between the float (8) and the air inlet (9). It also includes a first support ring (6) connected to the lower end of the guide screw (4). The first support ring (6) is a flexible ring. The float (8) is constrained within the space enclosed by the guide screw (4) and located between the sealing ring (3) and the first support ring (6).

3. The float-type vacuum breaker valve for a water turbine according to claim 2, characterized in that, The upper end surface of the sealing ring (3) is provided with an annular groove coaxial with the sealing ring (3), and also includes a second support ring (12) embedded in the annular groove and located at the bottom side of the annular groove; Multiple compression springs (13) are provided between the partition (2) and the second support ring (12), and the compression springs (13) are arranged at intervals around the circumferential direction of the second support ring (12); The lower end of the sealing ring (3) has a spherical surface for cooperating with the float (8), and the lower end of the second support ring (12) faces the spherical surface; When the float (8) separates from the sealing ring (3), the compression spring (13) is in an elastic compression state or a free extension state.

4. The float-type vacuum breaker valve for a water turbine according to claim 3, characterized in that, Each compression spring (13) is fitted with a separate spring groove on the lower end of the partition (2), and the upper end of each compression spring (13) is embedded in the spring groove that is fitted with it.

5. The float-type vacuum breaker valve for a water turbine according to claim 3, characterized in that, It also includes a guide groove (11) provided on the lower end of the partition (2), the inner side of the guide groove (11) is connected to the annular groove, and the outer side of the guide groove (11) is located outside the sealing ring (3).

6. The float-type vacuum breaker valve for a water turbine according to claim 5, characterized in that, It also includes a filter screen (10) filled in the guide groove (11); The number of the through slots (11) is greater than or equal to 1; When the number of guide grooves (11) is greater than 1, the guide grooves (11) are arranged at intervals in the circumferential direction of the annular groove, and each guide groove (11) is provided with a filter screen (10).

7. The float-type vacuum breaker valve for a water turbine according to claim 2, characterized in that, It also includes a support plate (7), the first support ring (6) is supported on the support plate (7), and the stacked structure formed by the first support ring (6) and the support plate (7) is locked to the lower end of the guide screw (4) by a locking nut. Each guide screw (4) is equipped with a locking nut for locking the stacked structure.

8. The float-type vacuum breaker valve for a water turbine according to claim 2, characterized in that, It also includes a ring-shaped pressure plate (14), the upper end of the sealing ring (3) is in contact with the bottom surface of the partition (2), and the lower end of the sealing ring (3) is supported on the pressure plate (14); The pressure plate (14) is equipped with screw holes for the guide screws (4) to pass through the pressure plate (14). Each guide screw (4) is equipped with a separate screw hole. Each guide screw (4) passes through the pressure plate (14) through the screw hole. The pressure plate (14) is slidable relative to the guide screws (4). The stacked structure formed by the pressure plate (14) and the sealing ring (3) is locked to the guide screw (4) by locking nuts. Each guide screw (4) is equipped with a locking nut for locking the stacked structure.

9. The float-type vacuum breaker valve for a water turbine according to claim 2, characterized in that, Each guide screw (4) is fitted with a flexible sleeve (5).

10. The float-type vacuum breaker valve for a water turbine according to any one of claims 1 to 8, characterized in that, The float (8) comprises a hollow steel ball and a polytetrafluoroethylene (PTFE) surface covering the outside of the hollow steel ball.

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