Dynamic sealing device of turbine pump

Abstract

The utility model provides a dynamic sealing device of a turbine pump. The dynamic sealing device at least comprises a shell, a static ring assembly and a dynamic ring. The static ring assembly and the moving ring are arranged in the shell; the static ring assembly comprises a graphite ring, a static ring seat, a corrugated pipe and a rear seat which are sequentially arranged in the shell, and the graphite ring is in contact with the moving ring; the graphite ring is in spherical fit with the static ring seat and is connected with the static ring seat through an anti-rotating pin; one end of the corrugated pipe is connected with the static ring seat, and the other end of the corrugated pipe is connected with the inner wall of the shell through the rear seat; wherein the corrugated pipe is in a compressed state.

Description

Technical Field

[0001] The utility model relates to the technical field of rocket engines, in particular to a turbine pump dynamic sealing device. Background Art

[0002] As an important component of a pump-type liquid rocket engine, the turbopump is used to pressurize the tank medium to provide the engine with the required oxidant and fuel. To prevent propellant leakage, the turbopump needs to be equipped with an effective dynamic seal.

[0003] The performance of the dynamic seal will directly determine the life and reliability of the turbo pump, and is one of the key technologies of liquid rocket engines. Existing dynamic seals are mainly contact-type end face seals, which have the following main disadvantages:

[0004] 1) When the turbine pump is working, the sealing end face is always in contact with friction, resulting in large wear of the graphite ring;

[0005] 2) The interference fit structure between the graphite ring and the stationary ring seat causes a large deformation of the sealing surface during operation, especially under low-temperature media, which further aggravates the wear of the graphite ring;

[0006] 3) The stationary ring assembly adopts a bellows structure. Due to the production process of the bellows, the coaxiality of the stationary ring assembly is difficult to ensure. After assembly, the sealing end face of the stationary ring assembly and the sealing end face of the dynamic ring are usually seriously eccentric.

[0007] The above problems seriously reduce the life and reliability of dynamic seals. Utility Model Content

[0008] In order to solve the above technical problems, the utility model proposes a turbine pump dynamic sealing device, which can not only always maintain the coaxiality of the dynamic ring and the static ring assembly, but also eliminate the hidden danger of deformation of the static ring seat and the butt end face of the graphite ring, and at the same time avoid the dynamic ring and the graphite ring from always being in contact and friction.

[0009] The utility model provides a turbine pump dynamic sealing device, which at least comprises a shell, a stationary ring assembly and a dynamic ring; the stationary ring assembly and the dynamic ring are arranged in the shell; the stationary ring assembly comprises a graphite ring, a stationary ring seat, a bellows and a back seat which are sequentially arranged in the shell, and the graphite ring is arranged in contact with the dynamic ring; the graphite ring is spherically matched with the stationary ring seat and is connected by an anti-rotation pin; one end of the bellows is connected to the stationary ring seat, and the other end is connected to the inner wall of the shell through the back seat; wherein the bellows is in a compressed state.

[0010] In one embodiment, the dynamic ring and the graphite ring are coaxially arranged, one radial side of the sealing end face of the dynamic ring cooperates with the graphite ring, and the other radial side cooperates with the shaft shoulder; the end face of the dynamic ring in contact with the graphite ring is provided with a dynamic pressure groove, and the end face of the dynamic ring in contact with the shaft shoulder is lower than the end face where the dynamic pressure groove is provided.

[0011] In one embodiment, local notches are respectively provided at the positions where the stationary ring seat and the graphite ring surface cooperate, for installing the anti-rotation pin; one end of the anti-rotation pin is fixed in the local notch of the stationary ring seat, and the other end cooperates with the gap of the inner wall of the local notch of the graphite ring.

[0012] In one embodiment, an annular spring is provided between the radial periphery of the stationary ring seat and the housing; the annular spring is sleeved on the radial periphery of the stationary ring seat to limit the radial movement of the stationary ring seat.

[0013] In one embodiment, an anti-rotation ear is provided on the radial periphery of the stationary ring seat, and the shell is provided with a gap for the anti-rotation ear to move axially and limit its circumferential rotation, and the radial outer end surface of the anti-rotation ear is gap-matched with the inner wall of the shell.

[0014] In one embodiment, the distance between the end surface of the anti-rotation ear facing the dynamic ring and the inner wall of the shell is L, the distance between the end surface of the stationary ring seat facing the dynamic ring and the end surface of the graphite ring facing the dynamic ring is H, and L is smaller than H.

[0015] In one embodiment, the depth of the dynamic pressure groove ranges from 5 to 20 μm.

[0016] In one embodiment, a wear-resistant coating is provided on the end surface of the dynamic ring in contact with the graphite ring, and the thickness of the wear-resistant coating is greater than the depth of the dynamic pressure groove and less than 0.3 mm.

[0017] In one embodiment, the outer diameter of the sealing end surface of the dynamic ring is larger than the outer diameter of the sealing end surface of the graphite ring.

[0018] In one embodiment, the anti-rotation pin and the local notch of the stationary ring seat are fixed by applying an adhesive.

[0019] The utility model provides a turbine pump dynamic sealing device, which has at least one of the following beneficial effects:

[0020] 1. The turbine pump dynamic seal device of the utility model can always maintain the coaxiality of the dynamic ring and the static ring assembly by installing an annular spring between the static ring seat and the shell.

[0021] Second, the dynamic seal device of the turbine pump of the utility model adopts a spherical connection structure between the graphite ring and the stationary ring seat, and adopts a matching method to ensure the sealing. The graphite ring and the stationary ring seat are installed by the anti-rotation pin and the local notch, eliminating the deformation risk of the spherical surface of the stationary ring seat and the graphite ring.

[0022] 3. The turbine pump dynamic seal device of the utility model is provided with a dynamic pressure groove on the sealing end surface of the dynamic ring, thereby avoiding the dynamic ring and the graphite ring from always being in contact and rubbing.

[0023] 4. The turbine pump dynamic seal device of the utility model significantly improves the service life and reliability of the turbine pump dynamic seal of the liquid rocket engine, and can meet the demand for the reuse of liquid rockets.

[0024] Those skilled in the art will recognize additional features and advantages upon reading the detailed description and upon viewing the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] In order to more clearly illustrate the embodiments of the utility model or the technical solutions in the prior art, the drawings required for use in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the utility model. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0026] Figure 1 It is a schematic diagram of the overall structure of the turbine pump dynamic sealing device of an embodiment of the utility model.

[0027] Figure 2 It is a structural schematic diagram of the dynamic ring of an embodiment of the utility model.

[0028] Figure 3 It is a structural schematic diagram and a cross-sectional diagram of the stationary ring seat of an embodiment of the utility model.

[0029] Figure 4 It is a cross-sectional view of a graphite ring according to an embodiment of the utility model. DETAILED DESCRIPTION

[0030] The features and exemplary embodiments of various aspects of the present invention will be described in detail below. In order to make the purpose, technical solutions and advantages of the present invention clearer, the present invention will be further described in detail below in conjunction with the accompanying drawings and specific embodiments. It should be understood that the specific embodiments described herein are only configured to explain the present invention and are used to illustrate the principles of the present invention, and are not configured to limit the present invention. In addition, the structural components in the drawings are not necessarily drawn to scale. For example, the sizes of some structural components or areas in the drawings may be enlarged for other structural components or areas to help understand the embodiments of the present invention.

[0031] The directional words appearing in the following description are all directions shown in the figures, and do not limit the specific structure of the embodiments of the utility model. In the description of the utility model, it should be noted that, unless otherwise specified, the terms "installation", "connection" and "connection" 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 directly connected or indirectly connected through an intermediate medium. For ordinary technicians in this field, the specific meanings of the above terms in the utility model can be understood according to the specific circumstances.

[0032] In addition, the terms "include", "comprise", "have" or any other variations thereof are intended to cover non-exclusive inclusion, so that a structure or component including a series of elements includes not only those elements, but also other mechanical elements that are not explicitly listed or inherent in the structure or component. In the absence of more restrictions, the elements defined by the sentence "include..." do not exclude the existence of other identical elements in the article or device including the elements.

[0033] Spatially related terms such as "below", "beneath", "under", "low", "above", "on", "high", etc. are used to facilitate description to explain the positioning of one element relative to a second element, indicating that these terms are intended to cover different orientations of the device in addition to orientations different from those shown in the figures. In addition, for example, "one element is above / below another element" can mean that the two elements are in direct contact, or that there are other elements between the two elements. In addition, terms such as "first", "second", etc. are also used to describe various elements, regions, parts, etc., and should not be regarded as limiting. Similar terms represent similar elements throughout the description.

[0034] For those skilled in the art, the present invention can be implemented without some of these specific details. The following description of the embodiments is only intended to provide a better understanding of the present invention by showing examples of the present invention.

[0035] See also Figure 1The utility model provides a turbine pump dynamic sealing device, which at least includes a housing 1, a stationary ring assembly 2 and a dynamic ring 3, wherein the stationary ring assembly 2 and the dynamic ring 3 are arranged in the housing 1. One axial end of the stationary ring assembly 2 abuts against the dynamic ring 3 to form a sealing surface, and the other end is connected to the housing 1. The stationary ring assembly 2 includes a graphite ring 21, a stationary ring seat 22, a bellows 23 and a back seat 24 which are sequentially arranged in the housing 1, wherein the graphite ring 21 contacts the dynamic ring 3 and abuts against it to form a sealing surface. The end face of the graphite ring 21 away from the dynamic ring 3 is spherically matched with the stationary ring seat 22, and in order to ensure the sealing performance, the two are processed by matching. An anti-rotation pin 25 is installed between the graphite ring 21 and the stationary ring seat 22, and the two are connected by the anti-rotation pin 25. One end of the bellows 23 is connected to the stationary ring seat 22, and the other end is connected to the inner wall of the housing 1 through the back seat 24.

[0036] The bellows 23 is in a compressed state, so that it can apply a force toward the dynamic ring 3 to the stationary ring seat 22 and the graphite ring 21 , so that the graphite ring 21 and the dynamic ring 3 are tightly matched.

[0037] The turbine pump dynamic seal device of the embodiment of the utility model realizes the spherical matching connection structure between the graphite ring and the stationary ring seat by matching grinding to ensure the sealing between the two. It can also prevent the sealing surface from deforming in a low temperature environment. The embodiment of the utility model uses an anti-rotation pin to connect the graphite ring and the stationary ring seat to prevent the two from rotating.

[0038] See also Figure 1 and Figure 2 In one embodiment, the dynamic ring 3 and the graphite ring 21 are coaxially arranged, and one radial side of the sealing end face of the dynamic ring 3 cooperates with the graphite ring 21, and the other side cooperates with the shaft shoulder. The end face of the dynamic ring 3 in contact with the graphite ring 21 is provided with a dynamic pressure groove 31. For example, the structure of the dynamic pressure groove 31 can be a spiral groove with a groove depth ranging from 5 to 20μm. In order to ensure the sealing performance of the sealing end face, the end face of the dynamic ring 3 in contact with the shaft shoulder is 0.5mm to 1.5mm lower than the end face where the dynamic pressure groove 31 is set. There is no need to set any structural form of static sealing between the end faces of the dynamic ring 3 and the shaft shoulder, but both need to ensure a certain degree of roughness and flatness.

[0039] See also Figure 2 In the above embodiment, a plurality of dynamic pressure grooves 31 are sequentially opened on the sealing end surface of the dynamic ring 3, so that the plurality of dynamic pressure grooves can achieve a pressure balance effect on the dynamic ring along the diameter direction of the dynamic ring 3, drive the pressure to be further evenly distributed, and achieve a better non-contact sealing effect.

[0040] The turbine pump dynamic seal device of the embodiment of the utility model can ensure that the sealing end face is not always in a state of contact friction when the turbine is working by arranging a dynamic pressure groove on the sealing end face of the dynamic ring. Therefore, the wear of the graphite ring can be greatly reduced, and the life and reliability of the dynamic seal can be significantly improved.

[0041] In one embodiment, in order to improve the hardness of the dynamic ring sealing end face, a wear-resistant coating may be provided on the end face of the dynamic ring that contacts the graphite ring. It should be noted that during the processing of the dynamic ring, a certain thickness of the wear-resistant coating needs to be applied first, and a dynamic pressure groove is processed on the wear-resistant coating, wherein the thickness of the wear-resistant coating is greater than the depth of the dynamic pressure groove and less than 0.3 mm.

[0042] See also Figure 1 , Figure 3 and Figure 4 In one embodiment, local notches are respectively provided at the positions where the stationary ring seat 22 and the graphite ring 21 are spherically matched, so as to install the anti-rotation pin 25. Specifically, the stationary ring seat 22 is provided with a first local notch 221, and the graphite ring 21 is provided with a second local notch 211. One end of the anti-rotation pin 25 is fixed in the first local notch 221, and the other end is gap-matched with the inner wall of the second local notch 211. The anti-rotation pin 25 and the graphite ring 21 are gap-matched to prevent the two from getting stuck.

[0043] The turbine pump dynamic sealing device of the embodiment of the utility model connects the stationary ring seat and the graphite ring by means of an anti-rotation pin and a local notch instead of an interference connection. This can prevent the sealing spherical surface of the stationary ring seat from being deformed due to the installation of the anti-rotation pin and also avoid the deformation problem that may be caused by an interference connection.

[0044] Furthermore, in order to ensure the reliability of the connection between the anti-rotation pin 25 and the stationary ring seat 22 , an adhesive may be applied to the position where the anti-rotation pin 25 is connected to the first local notch 221 for fixation.

[0045] See also Figure 1 In one embodiment, an annular spring 26 is provided between the radial periphery of the stationary ring seat 22 and the housing 1. In view of the elasticity of the annular spring 26, the radial movement of the stationary ring seat 22 can be appropriately limited by sleeve-arranging the annular spring 26 on the radial periphery of the stationary ring seat 22, thereby ensuring that the graphite ring 21 installed in the stationary ring seat 22 and the dynamic ring 3 have good coaxiality, eliminating the hidden danger of eccentricity of the sealing end faces of the stationary ring assembly and the dynamic ring.

[0046] Furthermore, there is a gap between each coil of the annular spring 26 in the embodiment of the utility model, so that the medium pressure can act on the bellows through the gap of the spring.

[0047] See also Figure 1 and Figure 3 In one embodiment, an anti-rotation ear 222 is provided on the radial periphery of the stationary ring seat 22, and the shell 1 is provided with a gap for the anti-rotation ear 222 to move axially and limit its circumferential rotation, and the radial outer end surface of the anti-rotation ear 222 is matched with the inner wall gap of the shell 1.

[0048] Among them, the distance between the end face of the anti-rotation ear 222 facing the dynamic ring 3 and the inner wall of the shell 1 is L, and the distance between the end face of the stationary ring seat 22 facing the dynamic ring 3 and the end face of the graphite ring 21 facing the dynamic ring 3 is H, wherein L is smaller than the H, so as to prevent metal friction between the stationary ring seat 22 and the dynamic ring 3 after the graphite ring 21 is damaged.

[0049] In one embodiment, in order to ensure the sealing performance of the dynamic sealing end surface, the outer diameter of the sealing end surface of the dynamic ring 3 is greater than the outer diameter of the sealing end surface of the graphite ring 21 .

[0050] The above embodiments can be combined with each other and have corresponding technical effects.

[0051] The turbine pump dynamic seal device of the utility model can always maintain the coaxiality of the dynamic ring and the static ring assembly, and at the same time can eliminate the deformation risk of the static ring seat and the butt end face of the graphite ring, which significantly improves the service life and reliability of the liquid rocket engine turbine pump dynamic seal and can meet the needs of liquid rocket reuse.

[0052] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A turbine pump dynamic sealing device, characterized in that: At least comprises a housing, a stationary ring assembly and a dynamic ring; the stationary ring assembly and the dynamic ring are arranged in the housing; The stationary ring assembly comprises a graphite ring, a stationary ring seat, a bellows and a back seat which are sequentially arranged in the housing, the graphite ring is arranged in contact with the dynamic ring; the graphite ring is spherically matched with the stationary ring seat and connected through an anti-rotation pin; one end of the bellows is connected to the stationary ring seat, and the other end is connected to the inner wall of the housing through the back seat; Wherein, the bellows is in a compressed state.

2. The turbine pump dynamic seal device according to claim 1, characterized in that: The moving ring and the graphite ring are coaxially arranged, one radial side of the sealing end face of the moving ring cooperates with the graphite ring, and the other radial side cooperates with the shaft shoulder; The end surface of the moving ring in contact with the graphite ring is provided with a dynamic pressure groove, and the end surface of the moving ring in contact with the shaft shoulder is lower than the end surface where the dynamic pressure groove is provided.

3. The turbine pump dynamic seal device according to claim 1, characterized in that: The positions where the stationary ring seat and the graphite ring surface match are respectively provided with local notches for installing the anti-rotation pin; One end of the anti-rotation pin is fixed in the local notch of the stationary ring seat, and the other end is gap-matched with the inner wall of the local notch of the graphite ring.

4. The turbine pump dynamic seal device according to claim 3, characterized in that: An annular spring is arranged between the radial periphery of the stationary ring seat and the housing; the annular spring is sleeved on the radial periphery of the stationary ring seat to limit the radial movement of the stationary ring seat.

5. The turbine pump dynamic seal device according to claim 4, characterized in that: The radial periphery of the stationary ring seat is provided with an anti-rotation lug, the shell is provided with a gap for the anti-rotation lug to move axially and limit its circumferential rotation, and the radial outer end surface of the anti-rotation lug is gap-matched with the inner wall of the shell.

6. The turbine pump dynamic seal device according to claim 5, characterized in that: The distance between the end surface of the anti-rotation ear facing the dynamic ring and the inner wall of the shell is L, the distance between the end surface of the stationary ring seat facing the dynamic ring and the end surface of the graphite ring facing the dynamic ring is H, and L is smaller than H.

7. The turbine pump dynamic seal device according to claim 2, characterized in that: The depth of the dynamic pressure groove ranges from 5 to 20 μm.

8. The turbine pump dynamic seal device according to claim 7, characterized in that: A wear-resistant coating is provided on the end surface of the dynamic ring in contact with the graphite ring, and the thickness of the wear-resistant coating is greater than the depth of the dynamic pressure groove and less than 0.3 mm.

9. The turbine pump dynamic seal device according to any one of claims 1 to 8, characterized in that: The outer diameter of the sealing end surface of the dynamic ring is greater than the outer diameter of the sealing end surface of the graphite ring.

10. The turbine pump dynamic seal device according to claim 3, characterized in that: The anti-rotation pin and the local notch of the stationary ring seat are fixed by applying adhesive.

Images