A device and method for solving the problem of excessive leakage of a mechanical seal of a turbine pump

Abstract

The application relates to a device and a method for solving the problem of excessive leakage of a mechanical seal of a turbine pump. The device comprises a turbine pump body, a gas supply device, a diaphragm box compensation mechanism, a rotating device and a leakage monitoring device. A mechanical seal cavity is formed in the turbine pump body. A static ring and a rotor structure comprising a dynamic ring are arranged in the mechanical seal cavity. The static ring comprises a first sealing surface, and the dynamic ring comprises a second sealing surface. The first sealing surface and the second sealing surface are in close contact. The rotor structure can rotate with the dynamic ring to make the second sealing surface abrade the first sealing surface. The gas supply device supplies test gas into the mechanical seal cavity to form a gas pressure field in the cavity. The diaphragm box compensation mechanism driven by the gas pressure field presses the first sealing surface of the static ring uniformly against the second sealing surface of the dynamic ring. The rotating device is connected with the rotor structure to drive the rotor structure to rotate. The leakage monitoring device is used for detecting the leakage of the test gas in the mechanical seal cavity.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of liquid rocket engines, in particular to a device and method for solving the problem of excessive leakage of the mechanical seal of a turbine pump. BACKGROUND

[0002] The turbine pump is a core component of the liquid rocket engine, and its performance directly affects the overall performance and reliability of the engine. When the liquid rocket engine is working, the turbine pump needs to deliver propellant at high pressure and high flow rate to the combustion chamber. The mechanical seal is one of the key components in the turbine pump, which is used to prevent the leakage of propellant between the pump cavity and the turbine cavity. If the mechanical seal has a large leakage problem, it will cause the loss of propellant, reduce the efficiency of the engine, and even cause engine failure, affecting the success of the entire space mission.

[0003] Currently, during the assembly of the turbine pump, excessive leakage of the mechanical seal is a common problem. The traditional treatment method mainly uses a rotating wrench to cooperate with a customized rotor assembly connection tool to manually rotate the turbine pump, and drives the turbine pump to operate by external force, so that the static ring and the dynamic ring in the mechanical seal correct and grind the contact surface in relative motion, in order to reduce the gap between them and thus reduce the leakage. However, when the grinding work continues to the preset time node, the leakage value is still higher than the standard range required by the design, and the final effect is difficult to achieve the expected result. In order to further meet the grinding accuracy requirement, the test personnel will disassemble and reassemble the turbine pump, and continuously assemble and adjust until the leakage of the mechanical seal meets the use requirement, but this method will greatly increase the time cost and labor cost, and also significantly increase the risk of damage to the parts-level parts.

[0004] Therefore, there is an urgent need for a device and method that can effectively solve the problem of excessive leakage of the mechanical seal of the turbine pump after assembly, in order to improve the success rate of the assembly of the mechanical seal of the turbine pump and adapt to the demand of large-scale assembly of the turbine pump. SUMMARY

[0005] Therefore, in order to solve the problem of excessive leakage of the mechanical seal of the turbine pump, a device and method for solving the problem of excessive leakage of the mechanical seal of the turbine pump are provided.

[0006] A device for solving the problem of excessive leakage of the mechanical seal of a turbine pump comprises:

[0007] The turbine pump body is internally provided with a mechanical seal cavity, and a static ring and a rotor structure are arranged in the mechanical seal cavity; the rotor structure comprises a dynamic ring, the static ring comprises a first sealing surface, and the dynamic ring comprises a second sealing surface; the first sealing surface and the second sealing surface are in contact and sealed; the rotor structure is rotatable to drive the dynamic ring to rotate, so that the second sealing surface grinds the first sealing surface;

[0008] A gas supply device is configured to supply a test gas into the interior of the mechanical seal cavity, and the test gas is configured to form a gas pressure field in the interior of the mechanical seal cavity.

[0009] A bellows compensation mechanism is configured to be at least partially matched with the static ring, and is driven by the gas pressure field, and is configured to uniformly press the first sealing surface against the second sealing surface.

[0010] A rotating device is configured to be connected with the rotor structure, and is configured to drive the rotor structure to rotate.

[0011] A leakage monitoring device is configured to detect the gas leakage amount of the test gas in the mechanical seal cavity.

[0012] In one of the embodiments, the rotor structure further comprises a shaft body, an inducer, an impeller, and a bearing.

[0013] The bearing seat is arranged in the interior of the mechanical seal cavity.

[0014] The bearing sleeve is arranged outside the shaft body, and the bearing is assembled with the bearing seat.

[0015] The inducer, the impeller, and the dynamic ring are all arranged outside the shaft body.

[0016] The rotating device comprises a rotating end and a matching end which are connected with each other.

[0017] The rotating end is arranged outside the mechanical seal cavity, and the matching end is arranged inside the mechanical seal cavity and is connected with the shaft body.

[0018] In one of the embodiments, the rotor structure further comprises an adjusting pad, and the adjusting pad is configured to adjust the axial gap between the dynamic ring and the static ring.

[0019] In one of the embodiments, the bellows compensation mechanism comprises a support structure, an elastic element, and a pressing part.

[0020] The support structure is arranged on the inner wall of the mechanical seal cavity.

[0021] The elastic element comprises a fixed end and a moving end.

[0022] The fixed end is connected with the support structure, and the pressing part is connected with the moving end.

[0023] The moving end is matched with the static ring through the pressing part, and the moving end is configured to drive the static ring to move.

[0024] The moving end is configured to approach and move away from the fixed end, so as to uniformly press the first sealing surface against the second sealing surface.

[0025] In one of the embodiments, the gas supply device comprises a gas container, a pressure reducing valve, a filter, an exhaust valve, and a tee structure, and the tee structure comprises a first port, a second port, and a third port.

[0026] The gas container is connected to an inlet end of a pressure reducing valve, an outlet end of the pressure reducing valve is connected to an inlet end of a filter, and an outlet end of the filter is connected to the first port.

[0027] The exhaust valve is connected to the second port, and the third port is connected to the inside of the mechanical seal cavity.

[0028] In one embodiment, the test gas is nitrogen.

[0029] In one embodiment, the leakage monitoring device is a float flowmeter, and the turbine pump body includes a leakage outlet connected to the mechanical seal cavity; and the detection end of the flowmeter is connected to the leakage outlet.

[0030] A method for solving the problem of excessive leakage of a turbine pump mechanical seal, which is applicable to any of the above-mentioned devices for solving the problem of excessive leakage of a turbine pump mechanical seal, and comprises:

[0031] The gas supply device, the rotating device, and the turbine pump body are respectively sealed and connected;

[0032] The test gas is input into the inside of the mechanical seal cavity by the gas supply device until the gas pressure value in the inside of the mechanical seal cavity is stabilized at a preset pressure value;

[0033] Then, the rotating device is used to rotate the rotor structure so as to perform the running-in of the first sealing surface and the second sealing surface.

[0034] After the running-in is started, the leakage monitoring device is used to continuously monitor the gas leakage of the test gas in the mechanical seal cavity.

[0035] In one embodiment, a preset leakage amount is set, and when the gas leakage monitored by the leakage monitoring device is continuously lower than the preset leakage amount, the running-in of the first sealing surface and the second sealing surface is stopped.

[0036] In one embodiment, a preset rotating state of the rotor structure in actual use of the turbine pump body is set as a preset rotating state.

[0037] The rotating device is used to rotate the rotor structure to the preset rotating state, and the running-in of the dynamic ring and the static ring is performed in the preset rotating state.

[0038] The turbine pump mechanical seal leakage exceeds the standard solving device comprises a turbine pump body, a gas supply device, a diaphragm box type compensation mechanism, a rotating device and a leakage monitoring device, a mechanical seal cavity is formed in the turbine pump body, a static ring and a rotor structure comprising a dynamic ring are arranged in the mechanical seal cavity, the static ring comprises a first sealing surface, the dynamic ring comprises a second sealing surface, and the first sealing surface and the second sealing surface are in close contact. The rotor structure rotates to drive the dynamic ring to rotate, so that the second sealing surface is ground with the first sealing surface. The gas supply device introduces test gas into the mechanical seal cavity to form a gas pressure field; the diaphragm box type compensation mechanism is driven by the gas pressure field to uniformly press the first sealing surface on the second sealing surface; the rotating device is connected with the rotor structure to drive the rotor structure to rotate and make the dynamic ring and the static ring ground; and the leakage monitoring device detects the leakage of the test gas in the mechanical seal cavity. The gas supply device introduces test gas to form a pressure field, drives at least part of the diaphragm box type compensation mechanism to cooperate with the static ring, drives the diaphragm box type compensation mechanism to uniformly press the first sealing surface of the static ring on the second sealing surface, and the rotating device drives the rotor structure to rotate to make the second sealing surface ground and correct the defects of the first sealing surface, thereby improving the close contact degree. The leakage monitoring device detects the leakage in real time to ensure the sealing effect. This scheme does not need to disassemble the turbine pump, avoids damaging the parts, reduces the labor and time cost, can effectively improve the close contact degree of the sealing surface, accurately solves the problem of excessive leakage, and improves the reliability of the mechanical seal and the assembly success rate of the turbine pump.

[0039] The turbine pump mechanical seal leakage exceeds the standard solving device has the above beneficial effects. BRIEF DESCRIPTION OF DRAWINGS

[0040] Figure 1 A cross-sectional view of the turbine pump mechanical seal leakage exceeds the standard solving device provided by the embodiments of the present application.

[0041] Figure 2 A local enlarged view of the dynamic ring and the static ring cooperation position provided by the embodiments of the present application.

[0042] LIST OF REFERENCE NUMERALS

[0043] 1000, turbine pump body; 1001, mechanical seal cavity; 1002, static ring;

[0044] 1010, dynamic ring; 1011, shaft body; 1012, inducer; 1013, impeller; 1014, bearing; 1015, adjusting pad; 1016, shaft sleeve; 1017, lock nut;

[0045] 2001, gas container; 2002, pressure reducing valve; 2003, filter; 2004, exhaust valve; 2005, three-way structure;

[0046] 3000, a bellows compensation mechanism; 3001, a support structure; 3002, an elastic element; 3003, a compression portion;

[0047] 4000, a rotating device;

[0048] 5000, a leakage monitoring device. DETAILED DESCRIPTION

[0049] In order to make the above objectives, features and advantages of the present application more apparent, specific embodiments of the present application will be described in detail below with reference to the accompanying drawings. In the following description, numerous specific details are set forth in order to provide a thorough understanding of the present application. However, the present application can be practiced in a number of different ways beyond the specific embodiments described and it is to be understood that the present application is not limited in this regard. In other instances, well-known methods have not been described in detail in order to avoid unnecessarily obscuring the present application.

[0050] In the description of the present application, it should be understood that, if there are terms such as "center", "longitudinal", "transverse", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential", etc. appear, these terms indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings, and are only for the purpose of facilitating the description of the present application and simplifying the description, and therefore cannot be understood as indicating or implying that the devices or elements referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as limiting the present application.

[0051] In addition, if the terms "first", "second" appear, these terms are only for the purpose of description, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Therefore, the features limited by "first", "second" can explicitly or implicitly include at least one of the features. In the description of the present application, if the term "multiple" appears, the meaning of "multiple" is at least two, such as two, three, etc., unless otherwise specifically limited.

[0052] In the present application, unless otherwise specifically defined and limited, if the terms "mounting", "connecting", "connecting", "fixing" and the like appear, these terms should be broadly understood. For example, it can be fixedly connected, or it can be detachably connected, or it can be integrated; it can be mechanically connected, or it can be electrically connected; it can be directly connected, or it can be indirectly connected through an intermediate medium; it can be the internal communication of two elements or the interaction relationship between two elements, unless otherwise specifically limited. For those skilled in the art, the specific meaning of the above terms in the present application can be understood according to the specific circumstances.

[0053] In the present application, unless specifically defined and limited otherwise, if there is a description of a first feature on a second feature, or similar descriptions, it can mean that the first and second features are in direct contact, or the first and second features are indirectly in contact through an intermediate medium. Moreover, the first feature can be above, above and above the second feature, or only indicates that the first feature is higher than the second feature in horizontal height. The first feature can be below, below and below the second feature, or only indicates that the first feature is lower than the second feature in horizontal height.

[0054] It should be noted that if an element is referred to as being "fixed" or "disposed" on another element, it can be directly on the other element or there can be an intermediate element. If an element is considered to be "connected" to another element, it can be directly connected to the other element or there can be an intermediate element. If present, the terms "vertical", "horizontal", "up", "down", "left", "right" and similar expressions used in the present application are only for illustrative purposes and do not represent the only implementation.

[0055] Referring to Figure 1 Figure 1 A cross-sectional view of the turbine pump mechanical seal leakage exceeding solution device provided by the embodiments of the present application. Figure 2 A partial enlarged view of the dynamic ring and static ring cooperation position, the turbine pump mechanical seal leakage exceeding solution device provided by the embodiments of the present application is shown as follows: it includes a turbine pump body 1000, a gas supply device, a diaphragm box type compensation mechanism 3000, a rotating device 4000 and a leakage monitoring device 5000.

[0056] A mechanical seal cavity 1001 is formed inside the turbine pump body 1000, and a static ring 1002 and a rotor structure including a dynamic ring 1010 are arranged inside the mechanical seal cavity 1001. The dynamic ring 1010 and the static ring 1002 form a movable seal. For the movable seal, specifically: the static ring 1002 includes a first sealing surface, and the dynamic ring 1010 includes a second sealing surface; after assembly, the first sealing surface and the second sealing surface are in contact and sealed. Among them, the first sealing surface and the second sealing surface are not shown in the figure, and only the surface of the static ring 1002 and the dynamic ring 1010 is defined as being in contact and sealed. The shape of the surface is not limited too much, and the cooperation concept of the first sealing surface and the second sealing surface is a conventional concept in the turbine pump, and the sealing effect between the first sealing surface and the second sealing surface will directly affect the gas leakage in the mechanical seal cavity.

[0057] ​When the rotor structure rotates, the dynamic ring 1010 rotates synchronously, and the rotating dynamic ring 1010 grinds the static ring 1002. Specifically, the second sealing surface grinds the first sealing surface, so that the slight protrusions and micro-deformations between the first sealing surface and the second sealing surface gradually grind and correct each other under the action of relative motion and pressure, so that the two sealing surfaces continuously contact and rub, the surfaces gradually become smoother and more flat, the fit is improved, and the leakage is reduced.

[0058] The gas supply device is used to introduce test gas into the mechanical seal cavity 1001 to form a gas pressure field in the cavity. At least part of the diaphragm box compensation mechanism 3000 cooperates with the static ring 1002, and the diaphragm box compensation mechanism 3000 is driven by the gas pressure field. Under the driving of the gas pressure field, at least part of the diaphragm box compensation mechanism 3000 moves, thereby pressing the static ring 1002 on the dynamic ring 1010, so that the first sealing surface is uniformly pressed on the second sealing surface.

[0059] The rotating device 4000 is connected with the rotor structure to drive the rotor structure to rotate and grind the dynamic ring 1010 and the static ring 1002. The leakage monitoring device 5000 detects the leakage of the test gas in the mechanical seal cavity 1001. The test gas is introduced by the gas supply device to form a gas pressure field, and the diaphragm box compensation mechanism 3000 presses the static ring 1002 on the dynamic ring 1010. The gas pressure field provides a uniform driving force for the diaphragm box compensation mechanism 3000. Under the action of the driving force, the diaphragm box compensation mechanism 3000 pushes the static ring 1002, so that the first sealing surface is uniformly pressed on the second sealing surface. Then, the rotating device 4000 drives the rotor structure to rotate to grind the dynamic ring 1010 and the static ring 1002. At this time, the grinding can be regarded as the running of the dynamic ring 1010 and the static ring 1002 in the turbine pump. The running refers to the behavior of grinding and modifying the movable sealing surface between the static ring 1002 and the dynamic ring 1010 under the action of relative motion and pressure. The fit of the mechanical sealing surface can be effectively improved, and the leakage monitoring device 5000 can detect the leakage in real time, so as to realize the targeted solution of the leakage of the turbine pump mechanical seal, and ensure the sealing performance of the mechanical seal.

[0060] For the test gas, its role is to form a gas pressure field and drive the diaphragm compensation mechanism 3000. The test gas is introduced into the mechanical seal cavity 1001 through the gas supply device to form a stable gas pressure field, and the diaphragm compensation mechanism 3000 drives the first sealing surface of the static ring 1002 to be uniformly pressed on the second sealing surface of the dynamic ring 1010, while the rotating device 4000 drives the rotor structure to rotate, so that the dynamic ring 1010 and the static ring 1002 correct the slight protrusions and deformation of the sealing surface through friction in relative motion. After the sealing surface is run-in, it gradually becomes smooth and flat, the fit is significantly improved, the leakage can be monitored in real time by the leakage monitoring device 5000 and continuously reduced until it meets the design standard, solving the problem of insufficient effect of traditional manual rotation run-in.

[0061] The leakage monitoring device 5000 real-time feedback leakage data, combined with the precise driving of the rotating device 4000, can dynamically adjust the run-in time according to the leakage, without disassembling the turbine pump to complete the sealing optimization.

[0062] For the above-mentioned diaphragm compensation mechanism 3000, its core role is to respond to the wear of the sealing surface, assembly error or component deformation through an elastic compensation mechanism to maintain the sealing performance. Specifically, the diaphragm compensation mechanism 3000 is a common concept in the art, usually composed of elastic elements such as bellows, installed in the static ring 1002 or dynamic ring 1010 of the mechanical seal. When the mechanical seal is working, under the action of medium pressure, spring force and dynamic force generated by rotation, the diaphragm compensation mechanism 3000 can produce elastic deformation, thereby automatically adjusting the axial position of the sealing surface, compensating for the gap changes caused by wear, thermal deformation or assembly deviation of the sealing end face, ensuring that the dynamic and static ring sealing surfaces always maintain close fit, thereby effectively reducing the leakage and improving the reliability and stability of the mechanical seal. On this basis, the specific setting structure of the diaphragm compensation mechanism 3000 can refer to the existing technology.

[0063] During the running-in process, the leakage monitoring device 5000 will monitor the leakage of the test gas in the mechanical seal cavity 1001 throughout the process in real time. Specifically, the detection end of the leakage monitoring device 5000 is in communication with the leakage outlet of the mechanical seal cavity 1001, continuously collects the test gas flow data discharged from the leakage outlet, and transmits the data to the monitoring control system in real time. As the rotating device 4000 drives the rotor structure to operate, the second sealing surface of the dynamic ring 1010 and the first sealing surface of the static ring 1002 continuously run-in under the action of the diaphragm type compensation mechanism 3000 driven by the gas pressure field, and the small protrusions and deformations of the sealing surfaces are gradually corrected, and the leakage will show a continuous downward trend. When the monitoring data shows that the gas leakage is stable below 3 ml / s (milliliter / second), it indicates that the fit of the first sealing surface and the second sealing surface has met the design requirements, at which time the monitoring control system will automatically issue a stop command to control the rotating device 4000 to stop operating, completing the running-in operation. This mechanism avoids the errors of traditional manual judgment through precise leakage threshold judgment, ensuring the running-in quality of the sealing surface and preventing excessive running-in from causing wear of the sealing surface, significantly improving the automation level and reliability of the turbine pump mechanical seal assembly.

[0064] In some embodiments of the present application, the shaft body 1011 of the rotor structure is sequentially sleeved with an inducer 1012, an impeller 1013, a dynamic ring 1010 and a bearing 1014 outside, a bearing seat is arranged inside the mechanical seal cavity 1001, and the bearing 1014 is assembled with the bearing seat; the rotating end of the rotating device 4000 is arranged outside the mechanical seal cavity 1001, and the matching end is arranged inside the mechanical seal cavity 1001 and connected with the shaft body 1011.

[0065] The shaft body 1011 of the rotor structure is sequentially sleeved with an inducer 1012, an impeller 1013, a dynamic ring 1010 and a bearing 1014 outside, and is assembled with the bearing seat inside the mechanical seal cavity 1001 through the bearing 1014, so that the components of the rotor structure are stably installed and can work cooperatively; the rotating end of the rotating device 4000 is arranged outside the mechanical seal cavity 1001, the matching end is arranged inside and connected with the shaft body 1011, which can effectively drive the rotor structure to rotate without affecting the sealing performance of the mechanical seal cavity 1001, thereby realizing the running-in of the dynamic ring 1010 and the static ring 1002, further improving the fit of the mechanical sealing surface, and ensuring the sealing performance of the mechanical seal.

[0066] In some embodiments of the present application, the rotor structure further comprises an adjusting pad 1015, which is used to adjust the axial gap between the dynamic ring 1010 and the static ring 1002. The adjusting pad 1015 of the rotating device 4000 is arranged between the dynamic ring 1010 and the static ring 1002, and is used to adjust the axial gap between the dynamic ring 1010 and the static ring 1002. The adjusting pad 1015 can also be arranged between other components of the rotor structure, and is used to adjust the axial gap between the components. By arranging the adjusting pad 1015 between the dynamic ring 1010 and the static ring 1002 and between other components of the rotor structure, the axial gap between the components can be accurately adjusted, ensuring that the installation positions of the components of the rotor structure are accurate and tightly matched, thereby improving the stability and operation accuracy of the rotor structure, further improving the fit between the second sealing surface of the dynamic ring 1010 and the first sealing surface of the static ring 1002, effectively solving the problem of excessive leakage of the mechanical seal of the turbine pump, and ensuring the sealing performance of the mechanical seal. Furthermore, the rotor structure further comprises a shaft sleeve 1016 arranged outside the shaft body 1011 and located between the impeller 1013 and the bearing 1014. The inner diameter of the shaft sleeve 1016 is in interference fit with the shaft body 1011, and the outer diameter of the shaft sleeve 1016 is matched with the inner ring of the impeller 1013 and the bearing 1014. The axial ends of the shaft sleeve 1016 abut against the hub end surface of the impeller 1013 and the inner ring end surface of the bearing 1014, respectively, and the axial position of the shaft sleeve 1016 is fixed by the locking nut 1017. The shaft sleeve 1016 can accurately control the axial distance between the impeller 1013 and the bearing 1014, ensure the relative position accuracy of the components in the rotor assembly, and avoid the offset of the fit between the second sealing surface of the dynamic ring 1010 and the first sealing surface of the static ring 1002 due to axial movement, thereby ensuring the reliability of the mechanical seal.

[0067] The locking nut 1017 is threadedly connected to the end of the shaft body 1011 and is located outside the shaft sleeve 1016. The end surface of the locking nut 1017 is tightly fitted with the end surface of the shaft sleeve 1016, and the components such as the shaft sleeve 1016, the impeller 1013, and the dynamic ring 1010 are axially fixed on the shaft body 1011 by tightening the locking nut 1017. The thread direction of the locking nut 1017 is opposite to the rotation direction of the shaft body 1011, and when the shaft body 1011 rotates, the thread cooperation will be tighter.

[0068] The specific structure and arrangement position of the inducer 1012, the impeller 1013, the dynamic ring 1010, the bearing 1014, the adjusting pad 1015, the shaft sleeve 1016, and the locking nut 1017 in the rotor structure can be arranged according to the prior art, as long as the above-mentioned matching relationship is ensured.

[0069] The whole running-in process is directly carried out after the turbine pump is assembled, without the need of disassembling and reassembling the components such as the rotor structure in the turbine pump, avoiding the risk of component damage caused by disassembly and reassembly, and saving the time cost of tool preparation, component cleaning and secondary assembly. After the running-in is completed, only the external modules such as the gas supply device and the rotating device need to be removed, and the turbine pump body can directly enter the installation link, ensuring that the assembly precision is not disturbed by disassembly, especially suitable for the high-reliability assembly requirements of liquid rocket engine turbine pumps, and significantly improving the assembly efficiency and product qualification rate in large-scale production.

[0070] In some embodiments of the present application, the diaphragm compensation mechanism 3000 includes a support structure 3001, an elastic element 3002, and a pressing portion 3003. The support structure 3001 of the diaphragm compensation mechanism 3000 is arranged on the inner wall of the mechanical seal cavity 1001, the fixed end of the elastic element 3002 is connected to the support structure 3001, and the moving end of the elastic element 3002 is matched with the static ring 1002 through the pressing portion 3003. The moving end can move close to and away from the fixed end, thereby uniformly pressing the second sealing surface of the dynamic ring 1010 by the first sealing surface of the static ring 1002. The pressing portion 3003 is partially connected to the moving end of the elastic element 3002, and the pressing portion 3003 is in surface contact with the static ring 1002. The fixed end of the elastic element 3002 is connected to the support structure 3001, and the support structure 3001 is fixed to the inner wall of the mechanical seal cavity 1001. When the test gas is introduced into the mechanical seal cavity 1001 to form a gas pressure field, the gas pressure acts on the elastic element 3002, causing it to elastically deform and drive the pressing portion 3003 to move towards the dynamic ring 1010, thereby pressing the static ring 1002 against the dynamic ring 1010. The pressing portion 3003 can automatically compensate for the wear of the sealing surface of the dynamic ring 1010 and the static ring 1002 under the action of the elastic element 3002, ensuring that the sealing surfaces of the two remain tightly bonded throughout the service life of the mechanical seal, thereby effectively reducing leakage. When the working pressure or rotational speed of the turbine pump changes, the gas pressure field in the mechanical seal cavity 1001 will also change accordingly, and the pressing portion 3003 can automatically adjust the pressing force on the static ring 1002 through the deformation of the elastic element 3002, so that the bonding pressure of the sealing surface remains within a reasonable range, thereby adapting to sealing requirements under different working conditions.

[0071] The support structure 3001 is a rigid structure, fixed to the inner wall of the mechanical seal cavity 1001 by bolt connection or welding, the axial position of the support structure 3001 corresponds to the static ring 1002, and the support structure 3001 keeps a non-contact state with the static ring 1002, only as a mounting carrier of the elastic element 3002, and does not directly participate in the driving of the static ring 1002. The support structure 3001 indirectly limits the maximum retreat distance of the static ring 1002 (when the elastic element 3002 is contracted) by constraining the fixed end of the elastic element 3002, so as to avoid the first sealing surface of the static ring 1002 from separating from the second sealing surface of the dynamic ring 1010 due to excessive movement.

[0072] The elastic element 3002 is preferably a diaphragm bellows, which has the elastic deformation ability of axial stretching and contraction. The diaphragm bellows is coaxially arranged with the axis of the mechanical seal cavity 1001 as a whole in a hollow cylindrical shape.

[0073] When the elastic element 3002 is stretched under the driving of the gas pressure field, the compression part 3003 uniformly transmits the elastic force to the static ring 1002, so that the first sealing surface of the static ring 1002 is tightly attached to the second sealing surface of the dynamic ring 1010 with uniform pressure.

[0074] The support structure 3001 of the diaphragm compensation mechanism 3000 is arranged on the inner wall of the mechanical seal cavity 1001, and provides stable support for the elastic element 3002; the moving end of the elastic element 3002 is connected to the surface of the static ring 1002 away from the dynamic ring 1010, and can move relative to the fixed end, so as to tightly press the static ring 1002 on the dynamic ring 1010 under the driving of the gas pressure field, effectively compensate the wear and deformation of the mechanical seal surface, ensure the sealing performance between the dynamic and static rings 1002, and solve the problem of excessive leakage of the turbine pump mechanical seal.

[0075] In some embodiments of the present application, the gas supply device includes a gas container 2001, a pressure reducing valve 2002, a filter 2003, an exhaust valve 2004, and a tee structure 2005; the tee structure 2005 includes a first port, a second port and a third port.

[0076] The gas container 2001 is connected to the inlet end of the pressure reducing valve 2002, the outlet end of the pressure reducing valve 2002 is connected to the inlet end of the filter 2003, and the outlet end of the filter 2003 is connected to the first port; the exhaust valve 2004 is connected to the second port, and the third port is connected to the inside of the mechanical seal cavity 1001. The gas container 2001 provides test gas, which is reduced in pressure by the pressure reducing valve 2002 to stabilize the pressure, and the filter 2003 filters impurities to ensure the cleanliness of the gas, and the three-way structure 2005 is connected to the exhaust valve 2004 and the mechanical seal cavity 1001, respectively, which can adjust and control the gas flow and pressure through the exhaust valve 2004, and can also pass the test gas with stable pressure into the mechanical seal cavity 1001 to form a gas pressure field, which provides power for the membrane box type compensation mechanism 3000 to drive the static ring 1002 to press the dynamic ring 1010, effectively solving the problem of excessive leakage of the turbine pump mechanical seal, and ensuring the sealing performance of the mechanical seal.

[0077] In some embodiments of the present application, the above-mentioned test gas is high-purity nitrogen, which is introduced into the inside of the mechanical seal cavity 1001 through the gas container 2001, the pressure reducing valve 2002, the filter 2003, the three-way structure 2005 and the like. Among them, the definition of high-purity nitrogen is: nitrogen with a purity of ≥99.993%.

[0078] Nitrogen is chemically stable and is not easy to react with the components in the mechanical seal cavity 1001, which can avoid the decline of the sealing performance caused by gas corrosion; nitrogen is non-toxic and harmless, safe and reliable to use, and will not harm the environment and personnel; as an inert gas, nitrogen can effectively isolate active gases such as oxygen, prevent the mechanical seal surface from being damaged due to oxidation, thereby prolonging the service life of the mechanical seal, ensuring the sealing performance of the mechanical seal, and effectively solving the problem of excessive leakage of the turbine pump mechanical seal.

[0079] In some embodiments of the present application, the turbine pump body 1000 is provided with a leakage outlet (not shown in the figure) connected to the mechanical seal cavity 1001, the float flowmeter is used as the leakage monitoring device 5000, the detection end of the float flowmeter is connected to the leakage outlet, the test gas flow discharged from the leakage outlet is detected by the float flowmeter, and thereby the leakage amount of the test gas in the mechanical seal cavity 1001 is obtained. The float flowmeter has simple structure, low cost and convenient installation, is directly connected to the leakage outlet of the turbine pump body 1000, can display the leakage amount of the test gas in real time and intuitively, and is convenient for the operator to quickly obtain the leakage data and timely understand the sealing state of the mechanical seal; the float flowmeter is used to accurately measure the test gas discharged from the leakage outlet, the sealing effect after the dynamic ring 1010 and the static ring 1002 are ground can be judged according to the measurement result, accurate data support is provided for solving the problem of excessive leakage of the turbine pump mechanical seal, and the sealing performance of the mechanical seal is effectively improved.

[0080] The utility model provides a kind of turbine pump mechanical seal leakage exceeds standard solution, it is suitable for the turbine pump mechanical seal leakage exceeds standard solution device described above, including:

[0081] Step one, gas supply device, rotating device 4000 and leakage monitoring device 5000 are respectively sealed with turbine pump body 1000 Connection;

[0082] Specifically: the tee structure 2005 third port of gas supply device is communicated with the mechanical seal cavity 1001 of turbine pump body 1000 by sealing connecting component;The rotating end of rotating device 4000 is fixedly installed outside mechanical seal cavity 1001, and the cooperation end is connected with shaft body 1011 by sealing shaft coupling, to ensure the sealing of connecting place, prevent gas leakage;The connecting part of rotating device 4000 and turbine pump body 1000 is sealed by sealing washer, sealing glue and the like sealing material, to realize tight connection.Leakage monitoring device 5000 is communicated with the leakage outlet of mechanical seal cavity 1001, and test gas continuously flows into leakage monitoring device 5000.

[0083] Ensure the sealing between gas supply device, rotating device 4000 and turbine pump body 1000, prevent test gas from leaking out, ensure that stable pressure field can be formed in mechanical seal cavity 1001, provide reliable test environment for subsequent steps, avoid inaccurate test data due to gas leakage, affect the judgment and processing of mechanical seal leakage exceeding standard.

[0084] Step two, test gas is inputted into the inside of mechanical seal cavity 1001 by gas supply device until the gas pressure value in the inside of mechanical seal cavity 1001 is stabilized at preset pressure value;

[0085] Specifically: open the valve of gas container 2001, test gas (nitrogen) is sequentially depressurized by pressure reducing valve 2002, filtered by filter 2003, and then passed into mechanical seal cavity 1001 by the third port of tee structure 2005;Adjust pressure reducing valve 2002 and exhaust valve 2004 to control gas flow and pressure, and monitor the pressure value in mechanical seal cavity 1001 in real time, stop adjusting when the pressure value reaches preset pressure value and remains stable.Form stable pressure field in mechanical seal cavity 1001, provide power for membrane box type compensation mechanism 3000 to drive static ring 1002 to compress dynamic ring 1010, so that static ring 1002 and dynamic ring 1010 are attached under suitable pressure, to facilitate more accurate detection and solution of mechanical seal leakage problem.Stable pressure field helps to ensure that the pressure between dynamic ring 1002 and static ring is uniform during subsequent running-in process, to improve running-in effect.

[0086] Step three, then, rotate rotor structure by rotating device 4000 to make the first sealing surface and the second sealing surface run-in;

[0087] Specifically, the rotating device 4000 is started, the rotating end transmits power to the matching end, the matching end drives the shaft body 1011 to rotate, and then the inducer 1012, the impeller 1013, the dynamic ring 1010 and other rotor structure components sleeved outside the shaft body 1011 rotate together; according to the material and structure of the mechanical seal, the appropriate rotating speed and rotating time are set, so that the second sealing surface of the dynamic ring 1010 and the first sealing surface of the static ring 1002 are fully run-in. Through the run-in, the fit of the sealing surfaces between the dynamic ring 1010 and the static ring 1002 can be further improved, the small defects and unevenness of the sealing surfaces can be eliminated, the sealing performance can be improved, the leakage of the mechanical seal can be effectively reduced, the friction pair between the dynamic ring 1010 and the static ring 1002 is better run-in, the wear during operation is reduced, and the service life of the mechanical seal is prolonged.

[0088] Step four, after the start of the run-in, the leakage monitoring device 5000 continuously monitors the gas leakage of the test gas in the mechanical seal cavity 1001.

[0089] Specifically, the detection end of the float flowmeter is in communication with the leakage outlet of the turbine pump body 1000, after the start of the run-in, the flow of the test gas discharged from the leakage outlet is monitored in real time, the measurement data is transmitted and displayed on the monitoring equipment in real time, and the operator can intuitively observe the change of the gas leakage. The leakage data of the test gas in the mechanical seal cavity 1001 can be obtained in real time and accurately, and the sealing effect of the mechanical seal during the run-in can be mastered in time; through the analysis of the leakage data, it is judged whether the run-in reaches the expected effect, which provides a basis for evaluating and adjusting the solution, and ensures that the problem of excessive leakage of the turbine pump mechanical seal is effectively solved.

[0090] In some embodiments of the present application, a preset leakage is set, and when the gas leakage monitored by the leakage monitoring device 5000 is continuously lower than the preset leakage, the run-in of the first sealing surface and the second sealing surface is stopped.

[0091] Specifically, according to the design standards and use requirements of the turbine pump mechanical seal, a preset leakage amount value is set in the monitoring device or control system; during the running-in process, the leakage monitoring device 5000 (float flowmeter) continuously monitors the leakage amount of the test gas in the mechanical seal cavity 1001, and transmits the data to the monitoring device in real time. The monitoring device compares the real-time leakage amount with the preset leakage amount; when the real-time leakage amount is continuously lower than the preset leakage amount, the monitoring device sends a signal to control the rotating device 4000 to stop running, thereby stopping the running-in of the second sealing surface of the dynamic ring 1010 and the first sealing surface of the static ring 1002. Setting the preset leakage amount provides a clear standard for judging whether the mechanical seal is qualified, and through real-time comparison and monitoring, it can accurately judge whether the running-in has achieved the expected effect; when the leakage amount is continuously lower than the preset value, stop running-in to avoid unnecessary wear of the dynamic and static rings 1002 caused by excessive running-in, save energy and time cost; at the same time, it ensures that the turbine pump mechanical seal is stopped in time after achieving good sealing performance, which guarantees the safe and stable operation of the turbine pump, and effectively solves the problem of excessive leakage of the mechanical seal.

[0092] In some embodiments of the present application, the rotating state of the rotor structure of the turbine pump body 1000 during actual use is set as a preset rotating state; the rotating device 4000 is used to rotate the rotor structure to the preset rotating state, and the second sealing surface of the dynamic ring 1010 and the first sealing surface of the static ring 1002 are run-in at the preset rotating state.

[0093] Specifically, first, the rotation speed, rotation direction and other parameters of the rotor structure in actual use are determined by consulting the design data or actual operation data of the turbine pump body 1000, so as to set the preset rotation state; during running-in, the rotating device 4000 is started, and the rotation state of the rotor structure is adjusted to the preset rotation state by adjusting the rotation speed adjusting part and the rotation control part of the rotating device 4000; under the condition that the rotor structure maintains the preset rotation state, the second sealing surface of the dynamic ring 1010 is run-in with the first sealing surface of the static ring 1002, and the rotation state of the rotor structure is monitored in real time by using a rotation speed sensor and other monitoring devices to ensure that it is maintained in the preset state. Running-in under the preset rotation state can more accurately detect and solve the leakage problem that may occur in actual use of the mechanical seal, avoid poor sealing performance caused by the fact that the running-in state does not match the actual working condition, and improve the reliability and stability of the turbine pump mechanical seal, thereby more effectively solving the problem of excessive leakage. When running-in under the preset state, if the ideal turbine pump mechanical seal condition is achieved, the probability of meeting the sealing standard of the turbine pump under actual working conditions can be increased. However, if the sealing cannot meet the standard under the preset state of the device, because the running-in environment provided by the device is simpler and more controllable than the actual working condition, the test gas is inert and has no corrosion of actual medium, and the rotation and pressure are more stable, the sealing still cannot meet the standard under the more optimal conditions, which indicates that the sealing surface has inherent defects such as macroscopic deformation and deep damage that cannot be repaired by running-in. These defects will be magnified in more complex actual working conditions, resulting in the fact that the sealing cannot meet the standard.

[0094] The technical features of the above embodiments can be combined in any manner. To make the description concise, not all possible combinations of the technical features in the above embodiments are described, but as long as the combinations of the technical features do not exist contradictions, they should be considered as the scope of the present disclosure.

[0095] The above embodiments only express several implementation manners of the present application, and the description is more specific and detailed, but it should not be understood as a limitation on the patent scope of the application. It should be noted that for ordinary skilled persons in the art, without departing from the concept of the present application, several modifications and improvements can be made, which are all within the protection scope of the present application. Therefore, the patent protection scope of the present application should be subject to the appended claims.

Claims

1. A device for solving the problem of excessive leakage of a mechanical seal of a turbopump, characterized in that, The turbine pump mechanical seal leakage amount exceeds the standard solving device includes: The turbine pump body is internally provided with a mechanical seal cavity, a static ring and a rotor structure are arranged in the mechanical seal cavity; the rotor structure includes a dynamic ring, the static ring includes a first sealing surface, and the dynamic ring includes a second sealing surface; the first sealing surface is in close contact with the second sealing surface; The gas supply device is used for introducing test gas into the inside of the mechanical seal cavity, and the test gas is used for forming a gas pressure field in the inside of the mechanical seal cavity; The diaphragm box type compensation mechanism is at least partially matched with the static ring, is driven by the gas pressure field, and is used for uniformly pressing the first sealing surface on the second sealing surface; The rotating device is connected with the rotor structure and is used for driving the rotor structure to rotate, so that the second sealing surface is ground with the first sealing surface; The leakage monitoring device is used for detecting the gas leakage amount of the test gas in the mechanical seal cavity; When the gas leakage amount monitored by the leakage monitoring device continuously is lower than the preset leakage amount, the grinding of the first sealing surface and the second sealing surface is stopped.

2. The device of claim 1, wherein, The rotor structure further includes a shaft body, an inducer, an impeller and a bearing; The inside of the mechanical seal cavity is provided with a bearing seat; The bearing is sleeved outside the shaft body, and the bearing is assembled with the bearing seat; The inducer, the impeller and the dynamic ring are all sleeved outside the shaft body; The rotating device includes a rotating end and a matching end connected with each other; The rotating end is arranged outside the mechanical seal cavity, and the matching end is arranged inside the mechanical seal cavity and connected with the shaft body.

3. The device of claim 2, wherein, The rotor structure further includes an adjusting pad; the adjusting pad is used for adjusting the axial gap between the dynamic ring and the static ring.

4. The device of claim 1, wherein, The diaphragm box type compensation mechanism includes a support structure, an elastic element and a pressing part; The support structure is fixed inside the mechanical seal cavity; The elastic element includes a fixed end and a moving end; The fixed end is connected with the support structure, and the pressing part is connected with the moving end; The moving end is matched with the static ring through the pressing part, and the moving end is used for driving the static ring to move; The moving end can be close to and away from the fixed end, so that the first sealing surface is uniformly pressed on the second sealing surface.

5. The device of claim 1, wherein, The gas supply device includes a gas container, a pressure reducing valve, a filter, an exhaust valve and a tee structure; the tee structure includes a first port, a second port and a third port; The gas container is communicated with the inlet end of the pressure reducing valve, the outlet end of the pressure reducing valve is communicated with the inlet end of the filter, and the outlet end of the filter is communicated with the first port; The exhaust valve is communicated with the second port, and the third port is communicated to the inside of the mechanical seal cavity.

6. The device of claim 1, wherein, The test gas is set as nitrogen.

7. The device of claim 1, wherein, The leakage monitoring device is set as a float flowmeter, the turbine pump body includes a leakage outlet communicated with the mechanical seal cavity; and a detection end of the flowmeter is communicated with the leakage outlet.

8. A method of solving the problem of excessive leakage of a mechanical seal of a turbopump, characterized in that, The turbine pump mechanical seal leakage amount exceeds the standard solving device, and the solving method includes: The gas supply device, the rotating device and the leakage monitoring device are respectively sealed and connected with the turbine pump body; The test gas is inputted into the inside of the mechanical seal cavity by the gas supply device until the gas pressure value of the inside of the mechanical seal cavity is stabilized at a preset pressure value; Then, the rotor structure is rotated by the rotating device to make the first seal surface and the second seal surface run-in; After the run-in starts, the leakage monitoring device continuously monitors the gas leakage amount of the test gas in the mechanical seal cavity.

9. The method of claim 8, wherein the turbine pump mechanical seal leakage is greater than 0.5 microliters per hour. The rotating state of the rotor structure of the turbine pump body in actual use is set as a preset rotating state; The rotor structure is rotated to the preset rotating state by the rotating device, and the dynamic ring and the static ring are run-in at the preset rotating state.

Images