Peak-shaving-resistant mechanical sealing mechanism and feed pump thereof
By designing the seal chamber in the mechanical sealing mechanism of the thermal power boiler water supply pump and filling it with coolant, the leakage and service life reduction caused by deformation of the seal friction end surface during peak shaving is solved, and the effective cooling of the seal ring and the service life are achieved.
Patent Information
- Application Number
- CN202421293055.1
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-06-07
- Publication Date
- 2025-03-11
- Estimated Expiration
- 2034-06-07
AI Technical Summary
The mechanical seal of the thermal power boiler water supply pump bears huge impact during peak regulating process, resulting in deformation of the friction end face of the seal, which in turn causes the problem of seal leakage and reduced service life.
A mechanical sealing mechanism that resists peak regulating is designed, by forming a sealing chamber between the pump shaft, sleeve, rotary ring, sealing gland and floating ring assembly, and filling the chamber with coolant, which flows through the end face of the sealing ring to reduce the temperature, and a cooling circulation system is provided to achieve continuous and stable cooling.
It effectively reduces the temperature of the end surface of the seal ring, reduces the accumulation of friction heat, extends the service life of the seal ring, and improves the stability and reliability of mechanical seals.
Smart Images
Figure CN222596380U_ABST
Abstract
Description
Technical Field
[0001] The utility model belongs to the technical field of mechanical equipment, and in particular relates to a mechanical sealing mechanism for resisting peak regulation and a water supply pump thereof. Background Art
[0002] In the thermal power generation industry, since thermal power generation is constrained by carbon emission indicators, the units of thermal power boiler feed pumps often have large peak loads, with the highest load reaching 70% of the unit load. This causes the mechanical seals of thermal power boiler feed pumps to be subjected to a great impact of peak loads, which in turn causes the water pressure in the mechanical seal chamber and the flow state of the water body to cause corresponding degradation changes in the friction of the sealing ring end face. At the same time, the rapid change in the pump speed also brings about abnormal changes in the friction of the sealing ring end face. Therefore, the rapid changes in the water pressure, the flow state of the water body and the pump speed cause the friction end face to overheat, which in turn causes the deformation of the sealing friction end face, which in turn causes the deformation of the friction end face to cause seal leakage, and the abnormal wear of the degraded seal end face leads to a decrease in the service life of the mechanical seal. Summary of the invention
[0003] Technical issues to be solved
[0004] In view of the shortcomings of the prior art, the purpose of the utility model is to provide a mechanical sealing mechanism and a water supply pump that can resist peak regulation, which solves the problems in the prior art of deformation of the sealing friction end face, which in turn leads to sealing leakage due to deformation of the friction end face, and abnormal wear of the sealing end face after deterioration, resulting in a decrease in the service life of the mechanical seal.
[0005] Technical Solution
[0006] In order to solve the above technical problems, on the one hand, the utility model provides such a mechanical sealing mechanism for resisting peak load regulation, comprising a pump shaft arranged in the housing of a water supply pump, a sleeve fixedly mounted on the outer wall of the shaft end of the pump shaft, and a rotating ring sleeved and fixedly connected to the sleeve, and the sleeve and the rotating ring both rotate synchronously with the pump shaft;
[0007] It also includes a sealing cover and a floating ring assembly, wherein the sealing cover is arranged at the axial end of the sleeve and is fixedly installed on the housing through fasteners, the floating ring assembly is arranged between the sealing cover and the rotating ring, and the sealing cover is used to abut one side end face of the floating ring assembly with one side end face of the rotating ring to form a sealing ring end face, so that a sealed chamber is formed between the floating ring assembly, the sealing cover and the housing, and the sealed chamber is filled with coolant, and the coolant passes through the sealing ring end face, and the coolant is used to reduce the temperature of the sealing ring end face.
[0008] Preferably, it also includes a cooling circulation mechanism for pumping cooling liquid into the annular cooling channel and located outside the mechanical sealing mechanism;
[0009] The cooling circulation mechanism has a liquid inlet and a liquid outlet. The liquid inlet of the cooling circulation mechanism is connected to the outlet pipe of the sealed chamber, and the liquid outlet of the cooling circulation mechanism is connected to the reflux pipe of the sealed chamber.
[0010] Preferably, it further comprises an automatic exhaust valve which is arranged on the shell and extends into the sealed chamber, and the automatic exhaust valve is used to exhaust the gas in the sealed chamber.
[0011] Preferably, the floating ring assembly comprises a floating ring seat and a floating ring, the floating ring is arranged in the floating ring seat, and the floating ring seat is fixed to the sealing cover by bolts.
[0012] Preferably, it also includes a spring arranged on the sealing cover and a push ring arranged between the spring and the floating ring, and the spring can push the push ring and the floating ring along the axial direction of the pump housing to make the floating ring fit with the rotating ring.
[0013] Preferably, the floating ring seat is a rotating body structure, and one end surface of the floating ring seat close to the floating ring is made of thick-walled wear-resistant graphite material.
[0014] Preferably, the outer peripheral wall of the floating ring seat is provided with stepped symmetrical step end faces in sequence from the inner side of the pump casing to the outer side of the pump casing along its axial direction.
[0015] Preferably, a first O-ring is provided between the shaft sleeve and the pump shaft for sealing, and a second O-ring is provided between the rotating ring and the shaft sleeve.
[0016] Preferably, a third O-ring is provided on a side of the outer side wall of the floating ring away from the rotating ring.
[0017] On the other hand, a water supply pump includes a pump casing, a pump shaft and the mechanical sealing mechanism. Beneficial Effects
[0018] Compared with the prior art, the beneficial effects of the utility model are:
[0019] The utility model discloses a mechanical seal mechanism and water pump for resisting peak load regulation. A sealed chamber is formed between the dynamic ring assembly, the sealing gland and the housing, and the sealed chamber is filled with coolant. The coolant can cool the end face of the sealing ring to pump the water in the sealed chamber to the external cooling circulation system, thereby achieving continuous and stable cooling, ensuring the loss of friction heat and conduction heat, and maintaining the optimization and stability of the working environment temperature of the sealing ring. The problem of deformation of the sealing friction end face in the prior art, which leads to sealing leakage caused by deformation of the friction end face, and abnormal wear of the deteriorated sealing end face leading to a decrease in the service life of the mechanical seal is solved. BRIEF DESCRIPTION OF THE DRAWINGS
[0020] Figure 1 It is a partial cross-sectional structural schematic diagram of a mechanical sealing mechanism for resisting peak regulation of the utility model;
[0021] Figure 2 for Figure 1 Detailed enlarged structural diagram at A.
[0022] [Description of Reference Numerals]
[0023] 1. Housing; 2. Pump shaft; 3. Bushing; 4. Rotating ring; 5. Sealing cover; 6. Floating ring assembly; 61. Floating ring seat; 62. Floating ring; 7. Fastener; 8. Spring; 9. Push ring; 10. First O-ring; 11. Second O-ring; 12. Fourth O-ring; 13. Third O-ring. DETAILED DESCRIPTION
[0024] In order to better explain the utility model and facilitate understanding, the utility model is described in detail below with reference to the accompanying drawings through specific implementation methods. Figure 1 The left side of the pump is defined as the outside of the pump. The side close to the pump shaft 2 is defined as the "inside".
[0025] In order to better understand the above technical solution, exemplary embodiments of the present invention will be described in more detail with reference to the accompanying drawings. Although exemplary embodiments of the present invention are shown in the accompanying drawings, it should be understood that the present invention can be implemented in various forms and should not be limited by the embodiments described herein. On the contrary, these embodiments are provided to enable a clearer and more thorough understanding of the present invention and to fully convey the scope of the present invention to those skilled in the art.
[0026] See also Figure 1-Figure 2, this specific embodiment is a feed water pump, which includes a pump casing 1, a pump shaft 2 and a mechanical sealing mechanism. The mechanical sealing mechanism includes a reinforced mechanical seal with frequent equipment startup, sudden changes in workload, slight deformation of the sealing friction end face, and slow deformation. It is mainly used in peak-shaving thermal power plants and shaft end sealing devices of boiler feed water pumps. Among them, the mechanical sealing mechanism for resisting peak shaving includes a pump shaft 2 arranged in the casing 1 of the feed water pump, a shaft sleeve 3 fixedly mounted on the outer wall of the shaft end of the pump shaft 2, and a rotating ring 4 fixedly mounted on the shaft sleeve 3, and the shaft sleeve 3 and the rotating ring 4 both rotate synchronously with the pump shaft 2. It also includes a sealing gland 5 and a floating ring assembly 6. The sealing gland 5 is arranged on the axial end of the sleeve 3 and is fixedly installed on the housing 1 through a fastener 7. The floating ring assembly 6 is arranged between the sealing gland 5 and the rotating ring 4. The sealing gland 5 is used to abut one side end face of the floating ring assembly 6 with one side end face of the rotating ring 4 to form a sealing ring end face, so that a sealed chamber is formed between the floating ring assembly 6, the sealing gland 5 and the housing 1. The sealing chamber is filled with coolant, and the coolant passes through the sealing ring end face. The coolant is used to reduce the temperature of the sealing ring end face.
[0027] In this embodiment, a pumping sheath is arranged outside the mechanical seal rotating ring 4, a conveying thread is arranged outside the sheath, and the rotating ring 4 and the outer sleeve are gap-matched; an O-ring seal is provided which also has a centering function, and three transmission holes are evenly arranged.
[0028] Moreover, an O-ring is arranged between the outer sleeve of the rotating ring and the shaft sleeve 6 to ensure that the rotating sealing ring deforms slightly and evenly when subjected to pressure and temperature, and that the deformation of both ends of the floating ring 62 is symmetrical relative to the geometric center. When the working environment changes, the deformation is slow and slight; and the liquid film between the two friction surfaces is ensured to be stable and well lubricated. The seal is reliable.
[0029] It should be noted that this design ensures that the deformation of the two sealing rings is minimal during operation, the liquid film between the friction surfaces is stable, and the wear and heat generation are optimized to the minimum.
[0030] The open pumping device arranged on the outside of the sealing rotating ring assembly pumps the water in the sealing chamber to the external cooling circulation system to achieve continuous and stable cooling, and the filtering device is used to filter (purify) the water, thereby ensuring the dissipation of friction heat and conduction heat, and maintaining the optimization and stability of the working environment temperature of the sealing ring.
[0031] The utility model also relates to a pump shaft sealing device, wherein the shaft sleeve 3 is arranged on the shaft end of the pump shaft 2, and a sealing gland 5 is arranged on the outer side of the sealing floating ring 62; a third O-type sealing ring 13 is arranged on the outer side of the back of the floating ring 62; the spring 8 is placed in the spring hole on the sealing gland 5, and a fourth O-type sealing ring 12 is arranged on the sealing gland 5. The spring 8 pushes the push ring 9, the floating ring 62 and the rotating ring 4 to fit together, and the rotating ring 4 is installed on the shaft sleeve 3. A second O-type sealing ring 11 is arranged between the rotating ring 4 and the shaft sleeve 3. It also includes a positioning plate installed on the sealing gland 5 and a shaft sleeve nut installed on the pump shaft and locked firmly by a half ring on the shaft. The shaft sleeve 3 and the pump shaft 2 are connected by a key to achieve synchronous driving and stopping. In this way, the whole water pump realizes the function that the water in the sealed chamber does not leak out of the pump body regardless of whether the pump is running or stationary.
[0032] Furthermore, a cooling circulation mechanism for pumping coolant into the annular cooling channel and located outside the mechanical sealing mechanism is also included. It should be noted that the external cooling circulation mechanism can be an existing cooling circulation mechanism, and no further elaboration is given here.
[0033] Furthermore, the cooling circulation mechanism has a liquid inlet and a liquid outlet, the liquid inlet of the cooling circulation mechanism is connected to the outlet pipe of the sealed chamber, and the liquid outlet of the cooling circulation mechanism is connected to the reflux pipe of the sealed chamber.
[0034] Furthermore, it also includes an automatic exhaust valve arranged on the housing 1 and extending into the sealed chamber, and the automatic exhaust valve is used to exhaust the gas in the sealed chamber. An automatic exhaust device is also provided in the sealed cooling circulation pipeline, and the gas in the sealed chamber is exhausted by the automatic exhaust valve. In this way, the sealed chamber is filled with liquid, and the friction heat of the sealing end face is taken away and dissipated in time, so that the friction end face of the mechanical seal is well cooled and lubricated.
[0035] Furthermore, the floating ring assembly 6 includes a floating ring seat 61 and a floating ring 62, wherein the floating ring 62 is arranged in the floating ring seat 61, and the floating ring seat 61 is fixed to the sealing gland 5 by bolts. Furthermore, the floating ring seat 61 is a rotating body structure, and one end face of the floating ring seat 61 close to the floating ring 62 is made of thick-walled wear-resistant graphite. Furthermore, the outer peripheral wall of the floating ring seat 61 is provided with stepped symmetrical step end faces from the inner side of the pump housing 1 to the outer side of the pump housing 1 in its axial direction. Thick-walled high-strength wear-resistant graphite is used at the end near the friction surface of the mechanical seal floating ring seat 61. The floating ring seat 61 is an axially symmetrical, fully rotating disc structure relative to the pump shaft 2, and the graphite inner ring adopts an outer circle notch bite to realize the anti-rotation function. The thickness of other conductive connection parts of the floating ring seat 61 decreases in sequence and is evenly arranged. The overall goal of achieving small and slow deformation of the friction end face under pressure and temperature is achieved. It is hoped that the deformation is slow enough to be eliminated by the operating friction before it causes sealing leakage. This will achieve the research and development goal of ensuring that the friction end faces of the mechanical seal are always well-matched during the entire use process and that there is no leakage in abnormal working conditions.
[0036] Furthermore, it also includes a spring 8 disposed on the sealing gland 5 and a push ring 9 disposed between the spring 8 and the floating ring 62. The spring 8 can push the push ring 9 and the floating ring 62 along the axial direction of the pump housing 1, so that the floating ring 62 fits with the rotating ring 4. This better makes the sealing ring end surface between the floating ring 62 and the rotating ring 4 in a sealed state.
[0037] Furthermore, a first O-ring 10 is provided between the shaft sleeve 3 and the pump shaft 2 for sealing, and a second O-ring 11 is provided between the rotating ring 4 and the shaft sleeve 3 .
[0038] Furthermore, a third O-ring 13 is disposed on the side of the outer wall of the floating ring 62 away from the rotating ring 4. The second O-ring 11 and the third O-ring 13 are disposed to ensure a good sealing effect of the sealed chamber.
[0039] In the description of the present utility model, it should be understood that the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Therefore, a feature defined as "first" or "second" may explicitly or implicitly include one or more of the features. In the description of the present utility model, the meaning of "plurality" is two or more, unless otherwise clearly and specifically defined.
[0040] In the present invention, unless otherwise clearly specified and limited, the terms "install", "connect", "connect", "fix" and the like should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium; it can be the internal connection of two elements or the interaction relationship between two elements. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.
[0041] In the present utility model, unless otherwise clearly specified and limited, when a first feature is “on” or “below” a second feature, it may be that the first and second features are in direct contact, or the first and second features are in indirect contact through an intermediate medium. Moreover, when a first feature is “above”, “above” or “above” a second feature, it may be that the first feature is directly above or obliquely above the second feature, or it may simply mean that the first feature is higher in level than the second feature. When a first feature is “below”, “below” or “below” a second feature, it may be that the first feature is directly below or obliquely below the second feature, or it may simply mean that the first feature is lower in level than the second feature.
[0042] In the description of this specification, the description of the terms "one embodiment", "some embodiments", "embodiment", "example", "specific example" or "some examples" etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the utility model. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art may combine and combine the different embodiments or examples described in this specification and the features of the different embodiments or examples, unless they are contradictory.
[0043] Although the embodiments of the present invention have been shown and described above, it can be understood that the above embodiments are exemplary and cannot be understood as limitations of the present invention. Ordinary technicians in the field can change, modify, replace and modify the above embodiments within the scope of the present invention.
Claims
1. A mechanical sealing mechanism for resisting peak load regulation, characterized in that: It comprises a pump shaft (2) arranged in a housing (1) of a water supply pump, a shaft sleeve (3) sleeved and fixedly mounted on the outer wall of the shaft end of the pump shaft (2), and a rotating ring (4) sleeved and fixedly connected to the shaft sleeve (3), wherein both the shaft sleeve (3) and the rotating ring (4) rotate synchronously with the pump shaft (2); The housing (1) further comprises a sealing gland (5) and a floating ring assembly (6). The sealing gland (5) is arranged at the shaft end of the shaft sleeve (3) and is fixedly mounted on the housing (1) via a fastener (7). The floating ring assembly (6) is arranged between the sealing gland (5) and the rotating ring (4). The sealing gland (5) is used to abut one end face of the floating ring assembly (6) against one end face of the rotating ring (4) to form a sealing ring end face, so that a sealing chamber is formed between the floating ring assembly (6), the sealing gland (5) and the housing (1). The sealing chamber is filled with a coolant, and the coolant passes through the sealing ring end face. The coolant is used to reduce the temperature of the sealing ring end face.
2. A mechanical sealing mechanism for resisting peak load regulation according to claim 1, characterized in that: Also included is a cooling circulation mechanism for pumping cooling liquid into the sealing chamber and located outside the mechanical sealing mechanism; The cooling circulation mechanism has a liquid inlet and a liquid outlet. The liquid inlet of the cooling circulation mechanism is connected to the outlet pipe of the sealed chamber, and the liquid outlet of the cooling circulation mechanism is connected to the reflux pipe of the sealed chamber.
3. A mechanical sealing mechanism for resisting peak load regulation according to claim 2, characterized in that: It also comprises an automatic exhaust valve which is arranged on the shell (1) and extends into the sealed chamber, and the automatic exhaust valve is used to exhaust the gas in the sealed chamber.
4. A mechanical sealing mechanism for resisting peak load regulation according to claim 1, characterized in that: The floating ring assembly (6) comprises a floating ring seat (61) and a floating ring (62); the floating ring (62) is arranged in the floating ring seat (61), and the floating ring seat (61) is fixed to the sealing gland (5) by means of bolts.
5. A mechanical sealing mechanism for resisting peak load regulation according to claim 4, characterized in that: It also includes a spring (8) arranged on the sealing cover (5) and a push ring (9) arranged between the spring (8) and the floating ring (62), wherein the spring (8) is capable of pushing the push ring (9) and the floating ring (62) along the axial direction of the housing (1) so that the floating ring (62) and the rotating ring (4) are in contact with each other.
6. A mechanical sealing mechanism for resisting peak load regulation according to claim 5, characterized in that: The floating ring seat (61) is a rotating body structural component, and an end surface of the floating ring seat (61) close to the floating ring (62) is made of thick-walled wear-resistant graphite material.
7. A mechanical sealing mechanism for resisting peak load regulation according to claim 6, characterized in that: The outer peripheral wall of the floating ring seat (61) is provided with stepped symmetrical step end faces in sequence from the inside of the shell (1) to the outside of the shell (1) along its axial direction.
8. A mechanical sealing mechanism for resisting peak load according to claim 7, characterized in that: A first O-type sealing ring (10) is provided between the shaft sleeve (3) and the pump shaft (2) for sealing, and a second O-type sealing ring (11) is provided between the rotating ring (4) and the shaft sleeve (3).
9. A mechanical sealing mechanism for resisting peak load according to claim 8, characterized in that: A third O-ring (13) is provided on a side of the outer wall of the floating ring (62) away from the rotating ring (4).
10. A water supply pump, characterized in that: It comprises a housing (1), a pump shaft (2) and the mechanical sealing mechanism according to any one of claims 1 to 9.