A liquid oxygen kerosene rocket engine kerosene pump expansion ring sealing device
Patent Information
- Application Number
- CN202522476113.5
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2025-11-21
- Publication Date
- 2026-09-25
- Estimated Expiration
- 2035-11-21
AI Technical Summary
由于轴系挠度及涡轮泵启动时产生的振动，轴向动密封的间隙量难以精准确定：间隙过大时泄漏量过大，间隙太小时动静件之间容易产生摩擦导致泄露量过大甚至密封失效
1、采用高性能碳-石墨材料制成的开口胀紧环，具有良好的回弹性和化学稳定性，在高压气体作用下，其能紧密贴合第一轴套环形槽侧壁与膜盒壳体内壁，形成可靠密封，实验表明，在开口胀紧环两侧压差达0.2MPa的情况下，泄漏量最大不超过300ml/s，满足密封设计要求，不同开口胀紧环上的卸荷口相互错开，进一步减少了泄漏量，保证了密封的稳定性；
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Figure CN224800393U_ABST
Abstract
Description
Technical Field
[0001] This utility model relates to the field of kerosene pump sealing for liquid oxygen kerosene rocket engines, and in particular to a shrink ring sealing device for a kerosene pump in a liquid oxygen kerosene rocket engine. Background Technology
[0002] In the operation system of liquid oxygen kerosene rocket engines, the kerosene pump, as a key fluid transport component, directly determines the engine's operational reliability and safety through its sealing performance.
[0003] Currently, kerosene pumps often employ axial dynamic seal structures that allow for a small amount of leakage, but this type of seal structure has significant drawbacks. Due to shaft deflection and vibrations generated during turbine pump startup, the clearance of the axial dynamic seal is difficult to determine precisely: if the clearance is too large, the leakage will be excessive; if the clearance is too small, friction between the moving and stationary parts can easily occur, leading to excessive leakage or even seal failure. Furthermore, ordinary metal expansion rings suffer from poor sealing performance at ultra-high speeds, are unsuitable for use with special media, and experience excessive wear during operation, preventing repeated use.
[0004] Therefore, in view of the above situation, there is an urgent need to develop a kerosene pump expansion ring sealing device for liquid oxygen kerosene rocket engines to overcome the shortcomings in current practical applications. Utility Model Content
[0005] The purpose of this utility model embodiment is to provide a sealing device for the expansion ring of a kerosene pump in a liquid oxygen kerosene rocket engine, which aims to solve the problems mentioned in the background art.
[0006] To achieve the above objectives, this utility model provides the following technical solution: A sealing device for a kerosene pump in a liquid oxygen / kerosene rocket engine includes a shaft and a kerosene pump housing. A bearing, an adjusting shim, a rotating ring, and a second shaft sleeve are sequentially fitted onto the shaft and rotate synchronously at high speed. Multiple evenly distributed sealing grooves are formed on the outer wall of the shaft, and each sealing groove contains a sealing ring. The sealing rings are used to achieve sealing between the shaft and the rotating ring, and between the shaft and the first shaft sleeve. Multiple annular grooves are formed on the outer wall of the first shaft sleeve, and each annular groove contains an open-ended tightening ring. Each open-ended tightening ring has a relief port. The adjusting shim is... Between the bearing and the rotating ring, the adjusting shim is pressed between its two ends and the bearing and the rotating ring respectively. The other end of the rotating ring abuts against the first bushing. The adjusting shim is internally threaded to a diaphragm housing. An O-ring is provided between the kerosene pump housing and the diaphragm housing. The second bushing is located on the side of the first bushing away from the rotating ring and abuts against the first bushing. The second bushing is used to press the first bushing. A high-pressure gas inlet is provided on the kerosene pump housing. A leakage channel is provided between the diaphragm housing and the kerosene pump housing. The outlet of the leakage channel is the leakage outlet.
[0007] In a further technical solution, the open expansion ring is made of high-performance carbon-graphite material.
[0008] In a further technical solution, the first bushing is made of high-hardness stainless steel, the width of the annular groove on the outer wall of the first bushing is greater than the thickness of the opening expansion ring, and the roughness of the inner wall of the annular groove is Ra1.6.
[0009] A further technical solution is that the unloading ports on the multiple open expansion rings are staggered, and the width of the unloading port is 0.2-0.4mm.
[0010] In a further technical solution, a gap of 0.4 mm is left between the inner wall of the diaphragm housing and the outer wall of the first bushing.
[0011] In summary, the embodiments of this utility model have the following beneficial effects compared with the prior art: 1. The open-end expansion ring, made of high-performance carbon-graphite material, has good resilience and chemical stability. Under high-pressure gas, it can tightly fit the side wall of the annular groove of the first bushing and the inner wall of the diaphragm housing to form a reliable seal. Experiments show that when the pressure difference on both sides of the open-end expansion ring reaches 0.2MPa, the maximum leakage does not exceed 300ml / s, which meets the sealing design requirements. The unloading ports on different open-end expansion rings are staggered to further reduce the leakage and ensure the stability of the seal. 2. The material properties of the open expansion ring enable it to withstand certain vibrations and impacts when the turbine pump starts, and it can work stably in special media such as liquid oxygen and kerosene. The first bushing is made of high-hardness stainless steel, and the inner wall of the annular groove has a roughness design of Ra.1.6, which reduces the wear of the open expansion ring during operation. 3. The 0.4mm gap between the inner wall of the diaphragm housing and the radial direction of the first bushing prevents friction caused by the deformation of the diaphragm housing or the first bushing due to centrifugal force under high-speed rotation, enabling the device to adapt to harsh working environments with high speed and high pressure. 4. The unloading port on the open expansion ring not only facilitates installation, but also reduces graphite wear and generates a liquid film on the end face, greatly extending its service life. At the same time, the components of this sealing device have a stable structure, low wear, and can be reused multiple times, reducing engine maintenance costs. 5. The components of this sealing device are reasonably designed. During assembly, only simple operations such as measuring the runout of the shaft end, adjusting the runout of the moving ring end face, and ensuring the orientation of the graphite opening tightening ring can be completed. The production process is relatively simple.
[0012] To more clearly illustrate the structural features and effects of this utility model, the following detailed description is provided in conjunction with the accompanying drawings and specific embodiments. Attached Figure Description
[0013] Figure 1 This is a schematic diagram of the cross-sectional structure of the present invention; Figure 2 This utility model Figure 1 A schematic diagram of the middle section structure; Figure 3 This is a schematic diagram of the cross-sectional structure of the first bushing in this utility model; Figure 4 This is a schematic diagram of the structure of the open expansion ring of this utility model.
[0014] In the diagram: 1. Shaft; 2. Opening expansion ring; 3. First shaft sleeve; 4. Sealing ring; 5. Moving ring; 6. Diaphragm housing; 7. O-ring seal; 8. Kerosene pump housing; 9. Adjusting shim; 10. Second shaft sleeve; 11. Bearing; 12. High-pressure gas inlet; 13. Drain outlet. Detailed Implementation
[0015] To make the objectives, technical solutions, and advantages of this utility model clearer, the present utility model will be 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 utility model and are not intended to limit this utility model.
[0016] The specific implementation of this utility model will be described in detail below with reference to specific embodiments.
[0017] like Figures 1-4As shown in the figure, this utility model embodiment provides a kerosene pump expansion ring sealing device for a liquid oxygen kerosene rocket engine, including a shaft 1 and a kerosene pump housing 8. A bearing 11, an adjusting shim 9, a moving ring 5, and a second shaft sleeve 10 are sequentially fitted onto the shaft 1 and rotate synchronously at high speed with the shaft 1. Multiple evenly distributed sealing grooves (not marked in the figure) are formed on the outer wall of the shaft 1, and a sealing ring 4 is provided in each of the sealing grooves. The sealing ring 4 is used to achieve sealing between the shaft 1 and the moving ring 5, and between the shaft 1 and the first shaft sleeve 3. Multiple annular grooves (not marked in the figure) are formed on the outer wall of the first shaft sleeve 3, and an open expansion ring 2 is provided in each of the annular grooves. Each open expansion ring 2 has a relief port (not marked in the figure). The adjusting shim 9 is positioned... Between the bearing 11 and the rotating ring 5, and with both ends of the adjusting shim 9 pressed against the bearing 11 and the rotating ring 5 respectively, the other end of the rotating ring 5 abuts against the first bushing 3. The adjusting shim 9 is internally threaded to the diaphragm housing 6, and an O-ring seal 7 is provided between the kerosene pump housing 8 and the diaphragm housing 6 to achieve a seal between them. The second bushing 10 is located on the side of the first bushing 3 away from the rotating ring 5, and the second bushing 10 abuts against the first bushing 3. The second bushing 10 is used to press the first bushing 3. A high-pressure gas inlet 12 is provided on the kerosene pump housing 8, and a leakage channel is provided between the diaphragm housing 6 and the kerosene pump housing 8. The outlet of the leakage channel is a leakage outlet 13, which is used to discharge the leakage medium of the sealing device.
[0018] Furthermore, the open expansion ring 2 is made of high-performance carbon-graphite material, which has good resilience and chemical stability and is suitable for a variety of chemical media.
[0019] Furthermore, the first bushing 3 is made of high-hardness stainless steel. The width of the annular groove on the outer wall of the first bushing 3 is greater than the thickness of the open expansion ring 2, and the roughness of the inner wall of the annular groove is Ra1.6, so as to reduce the wear of the open expansion ring 2 during operation.
[0020] Furthermore, the unloading ports on the multiple open expansion rings 2 are staggered, that is, the unloading ports on the open expansion rings 2 face two different directions. The width of the unloading port is 0.2-0.4mm. This unloading port not only facilitates the installation of the open expansion rings 2, but also reduces wear during operation and generates a liquid film on the end face, extending the service life. The unloading ports on the multiple open expansion rings 2 face different directions to further reduce leakage.
[0021] Furthermore, a 0.4mm gap is left between the inner wall of the membrane housing 6 and the outer wall of the first bushing 3 to prevent deformation due to centrifugal force under high-speed rotation and to avoid friction between parts.
[0022] Understandably, before assembling the sealing device, it is necessary to measure the end runout of shaft 1 to ensure that the end runout of shaft 1 is not greater than Φ0.03mm, so as to prevent the first bushing 3 from rubbing against the inner wall of the diaphragm housing 6 due to excessive end runout of shaft 1 during high-speed rotation.
[0023] In this embodiment of the invention, the open-end expansion ring 2, made of high-performance carbon-graphite material, possesses excellent resilience and chemical stability. Under high-pressure gas, it can tightly fit the side wall of the annular groove of the first bushing 3 and the inner wall of the diaphragm housing 6, forming a reliable seal. Experiments show that when the pressure difference across the open-end expansion ring 2 reaches 0.2 MPa, the maximum leakage does not exceed 300 ml / s, meeting the sealing design requirements. The unloading ports on different open-end expansion rings 2 are staggered, further reducing leakage and ensuring the stability of the seal. The material properties of the open-end expansion ring 2 allow it to withstand certain vibrations and impacts during turbine pump startup and enable stable operation in special media such as liquid oxygen and kerosene. The first bushing 3 is made of high-hardness stainless steel, combined with the Ra1.6 roughness design of the inner wall of the annular groove, reducing... The wear of the opening expansion ring 2 during operation is reduced; the 0.4mm gap between the inner wall of the diaphragm housing 6 and the radial direction of the first bushing 3 prevents friction caused by centrifugal deformation of the diaphragm housing 6 or the first bushing 3 under high-speed rotation, enabling the device to adapt to harsh working environments with high speed and high pressure; the unloading port on the opening expansion ring 2 not only facilitates installation but also reduces graphite wear and generates a liquid film on the end face, greatly extending its service life. At the same time, the components of this sealing device have stable structures and low wear, allowing for multiple reuses and reducing engine maintenance costs; the structural design of each component of this sealing device is reasonable, and the assembly process only requires simple operations such as measuring the runout of the shaft 1 end, adjusting the runout of the end face of the moving ring 5, and ensuring the opening orientation of the graphite opening expansion ring 2, making the production process relatively simple.
[0024] The working principle of this utility model is as follows: Before the kerosene pump of the liquid oxygen kerosene rocket engine is started, the pump cavity is in a vacuum state; after starting, high-pressure gas enters through the high-pressure gas inlet 12 on the kerosene pump housing 8, driving the entire rotor system (including shaft 1, bearing 11, adjusting shim 9, moving ring 5, first bushing 3, and second bushing 10) to rotate at high speed. Subsequently, the high-pressure gas enters the kerosene pump cavity and fills the cavity on the right side of the diaphragm housing 6 in a short time. The first bushing 3, which is equipped with the open expansion ring 2, rotates at high speed with the shaft 1 and is a moving part. The diaphragm housing 6 and the kerosene pump housing 8 are stationary parts. When the high-pressure gas in the kerosene pump cavity tries to pass through the open expansion ring 2 from direction A (towards the open expansion ring 2), it will lift the open expansion ring 2. Due to the large pressure difference between the two sides of the shaft 1 of the open expansion ring 2, the open expansion ring 2 is pressed into the annular groove of the first bushing 3. On the side wall, the side wall of the open-end expansion ring 2 forms a friction seal with the annular groove of the first shaft sleeve 3. Under the combined action of pressure difference and the material properties of the open-end expansion ring 2 itself, the two are tightly fitted together, achieving a good seal. At the same time, during the high-speed rotation of the rotor of shaft 1, the radially outer circular surface of the open-end expansion ring 2 is tightly fitted with the inner wall of the diaphragm housing 6, transforming the seal between the first shaft sleeve 3 and the diaphragm housing 6 into a local seal at the contact surface between the open-end expansion ring 2 and the diaphragm housing 6. At this time, the open-end expansion ring 2 is in a tightened state, further ensuring the sealing performance. During the start-up process, the open-end expansion ring 2, with its good resilience, can withstand the impact during start-up without structural damage. At the same time, a small amount of leakage medium is allowed to be discharged from the B direction (towards the leakage channel) through the pre-opened leakage channel between the diaphragm housing 6 and the kerosene pump housing 8 after passing through the open-end expansion ring 2.
[0025] The above description is only a preferred embodiment of the present utility model and is not intended to limit the present utility model. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present utility model should be included within the protection scope of the present utility model.
Claims
1. A kerosene pump expansion ring sealing device for a liquid oxygen kerosene rocket engine, comprising a shaft (1) and a kerosene pump housing (8), wherein a bearing (11), an adjusting shim (9), a moving ring (5), and a second bushing (10) are sequentially fitted on the shaft (1), and rotate synchronously at high speed with the shaft (1), characterized in that, The outer wall of the shaft (1) is provided with a plurality of evenly distributed sealing grooves, and each sealing groove is provided with a sealing ring (4). The sealing ring (4) is used to achieve sealing between the shaft (1) and the moving ring (5), and between the shaft (1) and the first bushing (3). The outer wall of the first bushing (3) is provided with a plurality of annular grooves, each annular groove being provided with an open expansion ring (2). Each open expansion ring (2) is provided with a load relief port. The adjusting shim (9) is provided between the bearing (11) and the moving ring (5), and both ends of the adjusting shim (9) are pressed against the bearing (11) and the moving ring (5) respectively. The other end of the moving ring (5) The adjusting pad (9) is internally threaded to the diaphragm housing (6) and abuts against the first bushing (3). An O-ring (7) is provided between the kerosene pump housing (8) and the diaphragm housing (6). The second bushing (10) is located on the side of the first bushing (3) away from the moving ring (5). The second bushing (10) abuts against the first bushing (3) and is used to press the first bushing (3). A high-pressure gas inlet (12) is provided on the kerosene pump housing (8). A leakage channel is provided between the diaphragm housing (6) and the kerosene pump housing (8). The outlet of the leakage channel is the leakage outlet (13).
2. The expansion ring sealing device for a liquid oxygen / kerosene rocket engine kerosene pump according to claim 1, characterized in that, The open expansion ring (2) is made of high-performance carbon-graphite material.
3. The expansion ring sealing device for a liquid oxygen / kerosene rocket engine kerosene pump according to claim 2, characterized in that, The first bushing (3) is made of high hardness stainless steel. The width of the annular groove on the outer wall of the first bushing (3) is greater than the thickness of the open expansion ring (2), and the roughness of the inner wall of the annular groove is Ra1.
6.
4. The expansion ring sealing device for a liquid oxygen / kerosene rocket engine kerosene pump according to claim 3, characterized in that, The unloading ports on the multiple open expansion rings (2) are staggered, and the width of the unloading port is 0.2-0.4mm.
5. The expansion ring sealing device for a liquid oxygen / kerosene rocket engine kerosene pump according to claim 4, characterized in that, A gap of 0.4 mm is left between the inner wall of the diaphragm housing (6) and the outer wall of the first bushing (3).