Oil mist sealing device of water-turbine generator set
By designing a multi-layer sealing structure and oil mist collection chamber in the hydrowheel generator set, the problem of oil mist overflow in the suspended high-speed hydrowheel generator set is solved, and zero leakage and safety of lubricating oil are achieved.
Patent Information
- Application Number
- CN202422265283.4
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-09-14
- Publication Date
- 2025-08-22
- Estimated Expiration
- 2034-09-14
AI Technical Summary
The existing maze and contact oil mist sealing devices cannot effectively prevent oil mist from overflowing in suspended high-head and high-speed water-wheel generator sets, causing oil mist to pollute the generator stator rod, rotor coil and wind tunnel equipment, affecting ventilation, heat dissipation and safety.
A multi-layer sealing structure consisting of an upper sealing cover, a lower sealing cover, an oil stabilizing plate, a wool felt, a contact follow-up sealing ring, a positioning sealing ring and a negative pressure buffer chamber are used to reduce lubricating oil overflow and achieve zero leakage through multiple sealing layers and a negative pressure buffer chamber.
In the suspended high-speed water-wheel generator set, zero leakage of lubricating oil is achieved, preventing oil mist from overflowing, reducing pollution and safety risks to the generator set, and improving ventilation and heat dissipation effect.
Smart Images
Figure CN223257524U_ABST
Abstract
Description
Technical Field
[0001] The utility model relates to the technical field of hydropower generation, in particular to an oil mist sealing device for a hydro-generator set. Background Art
[0002] Oil mist overflow from the lower oil trough is a common problem in hydro-turbine generators, particularly those with high-speed suspension. Over time, this oil mist overflow becomes increasingly severe, contaminating the generator's stator bars, rotor coils, and all equipment within the wind tunnel. If this oil mist overflow is not effectively addressed, it can negatively impact the generator's ventilation and heat dissipation, leading to reduced insulation, reduced unit output, and potentially creating safety risks such as environmental pollution and slips.
[0003] The current oil mist seal structures of hydro-generators are roughly divided into labyrinth oil mist seals and contact oil mist seals.
[0004] A labyrinth oil mist seal uses a series of tortuous channels (a maze path) to block the flow of oil mist. These channels are usually composed of a series of annular sealing teeth or baffles with small gaps between them. The oil mist needs to change direction multiple times when passing through these gaps, thereby dissipating its energy and achieving the purpose of reducing leakage.
[0005] Contact oil mist seals are seals formed through direct contact between a sealing element (such as a seal tooth or seal ring) and the shaft surface. The sealing element can follow the shaft's displacement and move radially, ensuring zero-gap contact even when the shaft swings, thereby effectively preventing oil mist leakage.
[0006] These existing sealing devices have a good sealing effect in preventing oil mist from overflowing from the oil tank in umbrella-type generator sets with medium and low water heads, but cannot effectively prevent oil mist from overflowing from the lower oil guide tank in suspended generator sets with high water heads and high speeds. Utility Model Content
[0007] The purpose of the utility model is to provide an oil mist sealing device for a hydro-generator set, which is applied to a suspended high-speed hydro-generator and can effectively solve the problem of oil mist overflow.
[0008] In order to achieve the above purpose, the technical solution adopted by the utility model is as follows:
[0009] An oil mist sealing device for a hydro-generator set, comprising an upper sealing cover, a lower sealing cover, an oil stabilizing plate, wool felt, a contact follower sealing ring, a positioning sealing ring, a negative pressure buffer chamber, and an oil mist collecting chamber;
[0010] The upper sealing cover and the lower sealing cover are coaxially assembled on the outer side of the main shaft of the hydro-generator; the upper sealing cover and the lower sealing cover are detachably connected; the lower sealing cover is mounted on the oil tank cover plate of the lower oil guide tank of the hydro-generator set.
[0011] The upper sealing cover is provided with wool felt, the inner ring surface of which contacts the main shaft; the upper sealing cover is also provided with a contact-type follower seal ring I in contact with the main shaft; a negative pressure buffer chamber is formed between the main shaft and the upper sealing cover; the wool felt, the contact-type follower seal I, and the negative pressure buffer chamber are arranged in order from top to bottom;
[0012] The lower sealing cover is provided with a contact follower sealing ring II, a contact follower sealing ring III and a positioning sealing ring that are in contact with the main shaft; an oil mist collection chamber is formed between the lower sealing cover and the main shaft;
[0013] The contact follower seal ring II, the oil mist collection chamber, the contact follower seal ring III, and the positioning seal ring are arranged in sequence from top to bottom;
[0014] An oil stabilizing plate is also provided on the lower sealing cover. A hole is opened at the center of the oil stabilizing plate to avoid the main shaft. The oil stabilizing plate is located between the positioning sealing ring and the oil groove cover plate; an oil return hole is provided on the oil stabilizing plate.
[0015] As a preferred technical solution, the connecting surfaces of the upper sealing cover and the lower sealing cover are coated with a sealing rubber layer and connected with bolts.
[0016] As an optimal technical solution, a placement groove is provided on the top of the upper sealing cover, and an annular mounting groove is provided on the side of the upper sealing cover adjacent to the main shaft. The placement groove and the mounting groove are respectively installed with wool felt and contact follower seal I; the contact follower seal I can float radially in the mounting groove.
[0017] As an optimal technical solution, the lower sealing cover is provided with an annular mounting groove on the side adjacent to the main shaft, and three mounting grooves are provided on the lower sealing cover from top to bottom, for installing a touch follower sealing ring II, a contact follower sealing ring III, and a positioning sealing ring respectively; the touch follower sealing ring II and the contact follower sealing ring III can float radially in the mounting groove; the inner ring surface of the positioning sealing ring is in close contact with the main shaft.
[0018] As an optimal technical solution, the upper sealing cover and the lower sealing cover are both split-assembly structures, and the upper sealing cover and the lower sealing cover are both made of four petals.
[0019] The four petals of the upper sealing cover are spliced together in pairs, and the splicing surfaces are coated with sealant; each of the four petals is provided with mounting lugs, and the adjacent two petals are spliced with the mounting lugs and connected together with bolts;
[0020] The four lobes of the lower sealing cover are spliced together in pairs, and the splicing surfaces are coated with sealant; each of the four lobes is provided with a mounting ear plate, and the adjacent two lobes are spliced with the mounting ear plates and connected together with bolts.
[0021] As a preferred technical solution, the lower sealing cover is symmetrically provided with oil guide pipes connected to the oil mist collection chamber.
[0022] As a preferred technical solution, an air-supplementing respirator is symmetrically provided on the upper sealing cover and is connected to the negative pressure buffer chamber.
[0023] As an optimal technical solution, the oil stabilizing plate is composed of four split parts, each of which has an oil return hole; the four split parts of the oil stabilizing plate are respectively installed on the four split parts of the lower sealing cover.
[0024] Compared with the prior art, the present invention has the following beneficial effects:
[0025] The overall structure is divided into 4 petals, with 5 layers of seals and an oil stabilizing plate. The oil stabilizing plate reduces the amount of lubricating oil overflowing from the main shaft under high speed of the unit. The combination of 3 contact follow-up seals and the oil tank cover forms an oil mist collection chamber and a negative pressure buffer chamber. Together with the final wool felt sealing layer, the oil tank cover sealing device can achieve zero leakage of lubricating oil mist overflowing from the lower oil guide tank.
[0026] For suspended high-speed hydro-turbine generators, the lubricating oil ejection caused by the large centrifugal force is intercepted by the oil stabilizing plate, so that the sealing effect is good for the high-speed hydro-turbine generator. BRIEF DESCRIPTION OF THE DRAWINGS
[0027] Figure 1 It is a front structural sectional view of the present utility model.
[0028] Figure 2 It is a side structural sectional view of the utility model.
[0029] Among them, the figure numbers are as follows: 1-lower sealing cover, 2-upper sealing cover, 3-oil stabilizing plate, 4-contact follower sealing ring I, 5-wool felt, 6-pressure plate, 7-contact follower sealing ring II, 8-contact follower sealing ring III, 9-ear plate, 10-oil return hole, 11-main shaft, 12-negative pressure buffer chamber, 13-oil mist collection chamber, 14-oil guide pipe, 15-positioning sealing ring. DETAILED DESCRIPTION
[0030] In order to make the purpose, technical solutions and advantages of this application more clearly understood, the present application is further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain this application and are not intended to limit this application.
[0031] On the contrary, this application covers any alternatives, modifications, equivalents, and solutions made within the spirit and scope of this application as defined by the claims. Furthermore, to facilitate a better understanding of this application, certain specific details are described in detail below in the detailed description of this application. Those skilled in the art will be able to fully understand this application without these details.
[0032] Example 1
[0033] like Figure 1-2 As shown, an oil mist sealing device of a hydro-generator set includes an upper sealing cover 2, a lower sealing cover 1, an oil stabilizing plate 3, wool felt 5, a contact follower sealing ring, a positioning sealing ring 15, a negative pressure buffer chamber 12, and an oil mist collecting chamber 13.
[0034] The upper sealing cover 2 and the lower sealing cover 1 are coaxially assembled on the outside of the main shaft 11 of the hydro-generator; the upper sealing cover 2 and the lower sealing cover 1 are detachably connected together. The lower sealing cover 1 is installed on the oil tank cover plate of the hydro-generator set.
[0035] A wool felt 5 is provided on the upper sealing cover 2, and the inner ring surface of the wool felt 5 is in contact with the main shaft 11; the upper sealing cover 2 is also provided with a contact follower sealing ring I4 in contact with the main shaft 11; a negative pressure buffer chamber 12 is formed between the main shaft 11 and the upper sealing cover 2; the wool felt 5, the contact follower seal I, and the negative pressure buffer chamber 12 are arranged in sequence from top to bottom.
[0036] The lower sealing cover 1 is provided with a contact follower sealing ring II7 , a contact follower sealing ring III8 , and a positioning sealing ring 15 in contact with the main shaft 11 ; an oil mist collecting chamber 13 is formed between the lower sealing cover 1 and the main shaft 11 .
[0037] The contact follower seal ring II, the oil mist collecting chamber 13, the contact follower seal ring III8, and the positioning seal ring 15 are arranged in sequence from top to bottom.
[0038] An oil stabilizing plate 3 is also installed on the lower sealing cover 1. A hole is opened in the center of the plate to provide clearance for the main shaft 11. The plate is located between the positioning seal ring 15 and the oil sump cover. An oil return hole 10 is also provided in the plate. This hole allows any oil leaking through the gap between the main shaft 11 and the plate to flow back to the oil sump.
[0039] Furthermore, the connection surface between the upper sealing cover 2 and the lower sealing cover is coated with a sealing adhesive layer and connected with bolts.
[0040] The working principle of this embodiment is as follows:
[0041] In a high-speed rotating hydro-turbine generator, the centrifugal force is relatively strong, and the centrifugal force on the lubricating oil in the oil tank also increases accordingly. During high-speed rotation, the lubricating oil is more easily thrown toward the edge or top of the oil tank under the action of centrifugal force, forming oil mist or oil droplets, which may then splash out of the oil tank and cause external throwing. In this embodiment, by providing an oil stabilizing plate 3 to seal the upward parabolic surface of the lubricating oil, the dynamic pressure portion of the oil flow is converted into static pressure, causing the oil flow to bend downward and flow, thereby reducing the generation of oil mist and oil throwing. The oil stabilizing plate 3 reduces the amount of lubricating oil that overflows from the main shaft 11 at high speeds of the generator set.
[0042] This embodiment designs five seals, namely, wool felt 5, contact follower seal I, contact follower seal ring II, contact follower seal ring III8, and positioning seal ring 15, to fully prevent oil mist from overflowing.
[0043] Furthermore, in some feasible embodiments, a placement groove is provided on the top of the upper sealing cover 2, and an annular mounting groove is provided on the side of the upper sealing cover 2 adjacent to the main shaft 11. The placement groove and the mounting groove are respectively used to mount the wool felt 5 and the contact follower seal 1. The contact follower seal 1 can float radially within the mounting groove, with a single-side forward movement of 1 mm and a rearward movement of 2 mm.
[0044] Furthermore, in some feasible embodiments, an annular mounting groove is provided on the side of the lower sealing cover 1 proximate to the main shaft 11. Three mounting grooves are provided on the lower sealing cover 1 from top to bottom, respectively for mounting a touch follower seal ring II, a contact follower seal ring III8, and a positioning seal ring 15. The touch follower seal ring II and the contact follower seal ring III8 can float radially within the mounting grooves, with a single-side forward movement of 1 mm and a rearward movement of 2 mm. The inner annular surface of the positioning seal ring 15 is in close contact with the main shaft 11.
[0045] Furthermore, in some feasible embodiments, both the upper sealing cover 2 and the lower sealing cover 1 are split and assembled, i.e., each is composed of four separate pieces. Specifically, the four separate pieces of the upper sealing cover 2 are joined together in pairs, and the joined surfaces are coated with sealant. Each of the four separate pieces is provided with mounting lugs 9, and adjacent two separate pieces are joined together by bolts.
[0046] The four lobes of the lower sealing cover 1 are spliced together in pairs, and the splicing surfaces are coated with sealant; each of the four lobes is provided with a mounting ear plate 9, and the adjacent two lobes are spliced with the mounting ear plates 9 and connected together with bolts.
[0047] Furthermore, in some feasible embodiments, an oil guide pipe 14 connected to the oil mist collection chamber 13 is symmetrically provided on the lower sealing cover 1, and the oil guide pipe 14 guides the mobile phone oil mist in the sealing cover to be collected outside the water wheel.
[0048] Furthermore, in some feasible embodiments, two symmetrical air-supplementing breathers are reserved on the upper sealing cover 2 and communicate with the negative pressure buffer chamber 12. These breathers are used to maintain a stable pressure inside the oil tank, prevent oil evaporation caused by excessive negative pressure, and reduce oil level fluctuations caused by pressure fluctuations. External air can enter the negative pressure buffer chamber 12 through the air-supplementing breathers to balance the pressure and maintain the stability of the lubricating oil in the oil tank.
[0049] Furthermore, in some feasible embodiments, the gap between the oil stabilizing plate 3 and the main shaft 11 is adjusted to between 0.5-0.8 mm, and the material of the oil stabilizing plate 3 is 3240 epoxy board.
[0050] Furthermore, in some feasible embodiments, the oil stabilizing plate 3 is composed of four split parts, each of which has an oil return hole 10 with a diameter of φ10; the four split parts of the oil stabilizing plate 3 are respectively installed on the four split parts of the lower sealing cover 1 by hexagonal head bolts.
[0051] Furthermore, in some feasible embodiments, the positioning sealing ring 15 is made of polytetrafluoroethylene (PTFE), which has the characteristics of wear resistance, corrosion resistance, self-lubrication and good sealing performance. The positioning sealing ring 15 is divided into 4 petals and installed in the installation groove of the lower sealing cover 1. The gap between each petal is less than 0.05 mm, ensuring the tightness of the seal. The sealing positioning ring is tightly pressed against the outer wall of the main shaft 11 to achieve a sealing effect.
[0052] Furthermore, in some feasible embodiments, the wool felt 5 seal has excellent elasticity and compression recovery, wear resistance, and chemical stability, does not contaminate the medium, and will not be swollen or corroded by the medium. After the follower seal ring is adjusted, the wool felt 5 is positioned in the placement groove and is tightened by a four-petal pressure plate 6 (made of Q235) through bolts to tightly fit the surface of the upper sealing cover 2, forming an effective sealing layer to prevent leakage of lubricating oil in the oil tank.
[0053] It is worth noting that, based on the above structural design, in order to solve the same technical problem, even if some insubstantial improvements are made on the basis of the present invention, they also fall within the scope of protection of the present invention.
Claims
1. An oil mist sealing device for a hydro-generator set, characterized in that: It includes an upper sealing cover, a lower sealing cover, an oil stabilizing plate, wool felt, a contact follower sealing ring, a positioning sealing ring, a negative pressure buffer chamber, and an oil mist collecting chamber; The upper sealing cover and the lower sealing cover are coaxially assembled on the outside of the main shaft of the hydro-generator; the upper sealing cover and the lower sealing cover are detachably connected; the lower sealing cover is mounted on the oil tank cover plate of the lower oil guide tank of the hydro-generator set; The upper sealing cover is provided with wool felt, the inner ring surface of which contacts the main shaft; the upper sealing cover is also provided with a contact-type follower seal ring I in contact with the main shaft; a negative pressure buffer chamber is formed between the main shaft and the upper sealing cover; the wool felt, the contact-type follower seal I, and the negative pressure buffer chamber are arranged in order from top to bottom; The lower sealing cover is provided with a contact follower sealing ring II, a contact follower sealing ring III and a positioning sealing ring that are in contact with the main shaft; an oil mist collection chamber is formed between the lower sealing cover and the main shaft; The contact follower seal ring II, the oil mist collection chamber, the contact follower seal ring III, and the positioning seal ring are arranged in sequence from top to bottom; An oil stabilizing plate is also provided on the lower sealing cover. A hole is opened at the center of the oil stabilizing plate to avoid the main shaft. The oil stabilizing plate is located between the positioning sealing ring and the oil groove cover plate; an oil return hole is provided on the oil stabilizing plate.
2. The oil mist sealing device of a hydro-generator set according to claim 1, characterized in that: The connecting surfaces of the upper sealing cover and the lower sealing are coated with a sealing adhesive layer and connected with bolts.
3. The oil mist sealing device of a hydro-generator set according to claim 1, characterized in that: A placement groove is provided on the top of the upper sealing cover, and an annular mounting groove is provided on the side of the upper sealing cover adjacent to the main shaft. The placement groove and the mounting groove are respectively used to install wool felt and contact follower seal I; the contact follower seal I can float radially in the mounting groove.
4. The oil mist sealing device for a hydro-generator set according to claim 3, characterized in that: The lower sealing cover is provided with an annular mounting groove on the side adjacent to the main shaft. The lower sealing cover is provided with three mounting grooves from top to bottom, for installing the touch follower sealing ring II, the contact follower sealing ring III, and the positioning sealing ring respectively; the touch follower sealing ring II and the contact follower sealing ring III can float radially in the mounting groove; the inner ring surface of the positioning sealing ring is in close contact with the main shaft.
5. The oil mist sealing device for a hydro-generator set according to claim 1, characterized in that: The upper sealing cover and the lower sealing cover are both split assembly structures, and the upper sealing cover and the lower sealing cover are both assembled by four petals; The four petals of the upper sealing cover are spliced together in pairs, and the splicing surfaces are coated with sealant; each of the four petals is provided with mounting lugs, and the adjacent two petals are spliced with the mounting lugs and connected together with bolts; The four lobes of the lower sealing cover are spliced together in pairs, and the splicing surfaces are coated with sealant; each of the four lobes is provided with a mounting ear plate, and the adjacent two lobes are spliced with the mounting ear plates and connected together with bolts.
6. The oil mist sealing device for a hydro-generator set according to claim 1, characterized in that: The lower sealing cover is symmetrically provided with an oil guide pipe connected with the oil mist collecting chamber.
7. The oil mist sealing device for a hydro-generator set according to claim 1, characterized in that: An air-supplementing respirator is symmetrically arranged on the upper sealing cover and is communicated with the negative pressure buffer chamber.
8. The oil mist sealing device for a hydro-generator set according to claim 5, characterized in that: The oil stabilizing plate is composed of four split parts, each of which has an oil return hole; the four split parts of the oil stabilizing plate are respectively installed on the four split parts of the lower sealing cover.