Multi-petal sealing ring double-end-face grinding device and method for liquid rocket engine

Abstract

The invention discloses a multi-petal sealing ring double-end-face grinding device and method for a liquid rocket engine, and solves the problems that in the prior art, single-face grinding is conducted on each petal piece of a multi-petal sealing ring, the phenomena that local end faces are not ground out, edges are collapsed, the petal pieces are difficult to overlap and the like exist, and the product rejection rate is extremely high. The grinding device comprises the upper grinding disc, the middle isolation plate, the lower grinding disc and the mandrel, the to-be-machined multi-petal sealing ring is arranged in the fan-shaped through hole of the middle isolation plate, the two axial ends of each petal are ground through the upper grinding face and the lower grinding face of the upper grinding disc and the lower grinding disc, the reliability of the product quality is greatly guaranteed, and the machining efficiency is improved. And an effective guarantee is provided for subsequent positioning reference.

Description

Technical Field

[0001] The present invention relates to a grinding device and method for a sealing ring, and particularly to a double-end grinding device and method for a multi-lobe sealing ring used in a liquid rocket engine. Background Art

[0002] The multi-lobe sealing ring is one of the most advanced sealing forms for current aerospace engines and is a thin-walled ring part composed of multiple fan-shaped segments. The end face of the multi-lobe sealing ring is an axial sealing band, and its inner hole is a radial sealing band; the processing quality of the multi-lobe sealing ring directly affects the reliability and safety of the seal, and further affects the performance of the entire engine. To ensure the sealing performance of the multi-lobe sealing ring, generally, there are very high geometric tolerance requirements for the parallelism, flatness, and roughness of its circumferential two end faces.

[0003] After the rough machining of the multi-lobe sealing ring is completed, usually, its blank part is used as a reference to machine the plane to ensure the overall geometric tolerance. However, due to the self-characteristics of the multi-lobe sealing ring, its processing and post-processing are difficult. There will be dimensional and geometric differences in each lobe (i.e., fan-shaped segment). The existing technology is to clamp each lobe individually, grind one end and then turn it around to grind the other end. Therefore, the dimensional consistency of its products is very poor, which further makes post-processing such as grinding and polishing more difficult and cumbersome. When grinding, it is necessary to ensure both the dimensional and geometric tolerance requirements of the multi-lobe sealing ring and at the same time ensure the surface quality and dimensional consistency of each lobe, which poses very high requirements for the post-processing procedure. For a long time, 10% - 30% of the products in each batch of multi-lobe sealing ring products have phenomena such as local non-grinding on the end face, edge collapse, and difficulty in lobe lap joint, resulting in a very high product rejection rate. Summary of the Invention

[0004] In order to solve the technical problems that in the prior art, each lobe of the multi-lobe sealing ring is ground separately on a single side, not only there are phenomena such as local non-grinding on the end face, edge collapse, and difficulty in lobe lap joint, resulting in a very high product rejection rate, but also there is poor product consistency. The present invention provides a double-end grinding device and method for a multi-lobe sealing ring used in a liquid rocket engine, which can not only ensure the dimensional and geometric tolerance consistency requirements of the multi-lobe sealing ring, but also reduce costs and improve production efficiency, and can effectively solve the existing problems and realize the improvement of quality and efficiency in the manufacturing of multi-lobe sealing ring products for rocket engines.

[0005] In order to achieve the above object, the present invention adopts the following technical solutions:

[0006] A double-end grinding device for a multi-lobe sealing ring used in a liquid rocket engine, characterized in that:

[0007] It includes a mandrel and an upper grinding disc, a middle isolation plate, and a lower grinding disc that are coaxially sleeved on the mandrel from top to bottom in sequence;

[0008] The top surface of the upper grinding plate is provided with a circumferentially downwardly recessed annular liquid addition groove, and the bottom of the annular liquid addition groove is provided with a plurality of abrasive addition holes penetrating through the upper and lower surfaces of the upper grinding plate. The bottom surface of the upper grinding plate is the upper grinding surface for grinding one axial end face of the multi-lobe seal ring to be processed; the upper grinding plate is detachably connected to the middle isolation plate;

[0009] The middle isolation plate is provided with fan-shaped through holes for placing each lobe of the multi-lobe seal ring to be processed, and the fan-shaped through holes penetrate through the upper and lower end faces of the middle isolation plate; the thickness of the middle isolation plate is less than the target thickness of the multi-lobe seal ring to be processed;

[0010] The upper end surface of the lower grinding plate is the lower grinding surface for grinding the other axial end face of the multi-lobe seal ring to be processed.

[0011] Further, a plurality of upper spoke-shaped narrow grooves are provided along the radial direction of the bottom surface of the upper grinding plate;

[0012] The number of the upper spoke-shaped narrow grooves is equal to the number of the abrasive addition holes in the annular liquid addition groove and they are in one-to-one correspondence and communication for storing abrasive and discharging grinding debris.

[0013] Further, a plurality of lower spoke-shaped narrow grooves are provided along the radial direction of the top surface of the lower grinding plate for storing abrasive and discharging grinding debris.

[0014] Further, a plurality of axial narrow grooves are provided along the circumferential direction of the outer wall of the mandrel for accommodating abrasive or impurities to prevent jamming.

[0015] Further, a downward upper circular protrusion is provided in the middle of the bottom surface of the upper grinding plate;

[0016] The upper grinding surface is the lower surface of the upper circular protrusion.

[0017] Further, an upward lower circular protrusion is provided in the middle of the top surface of the lower grinding plate;

[0018] The lower grinding surface is the upper surface of the lower circular protrusion.

[0019] Further, a grinding handle is provided on the upper grinding plate;

[0020] The grinding handle is located on the circumferential outer side of the upper circular protrusion.

[0021] Further, the upper grinding plate and the middle isolation plate are detachably connected by pins;

[0022] The pins are located on the circumferential outer side of the upper circular protrusion and are distributed at both ends of the same diameter of the upper grinding plate as the grinding handle.

[0023] Furthermore, two circular liquid addition grooves are provided on the upper grinding plate, and four abrasive addition holes are provided in each circular liquid addition groove; the four abrasive addition holes in the two circular liquid addition grooves correspond to each other along the radial direction of the upper grinding plate.

[0024] A multi-lobe seal ring double-end grinding method for a liquid rocket engine, using the above-mentioned multi-lobe seal ring double-end grinding device for a liquid rocket engine, is characterized in that it includes the following steps:

[0025] Step 1: Sleeve the lower grinding plate and the middle separator plate on the core shaft with the lower grinding surface of the lower grinding plate facing upward; then place each lobe of the multi-lobe seal ring to be processed in each sector-shaped through hole on the middle separator plate; then sleeve the upper grinding plate on the core shaft and place it on the top surface of the middle separator plate and each lobe, with its upper grinding surface facing downward;

[0026] Step 2: Add abrasive to the circular liquid addition groove, and the abrasive flows through the abrasive addition hole to between the upper grinding surface of the upper grinding plate and the upper end surfaces of each lobe of the multi-lobe seal ring to be processed. Drive the upper grinding plate to rotate around the core shaft, so that the upper grinding plate grinds the upper end surfaces of each lobe of the multi-lobe seal ring to be processed through its upper grinding surface and the abrasive for a preset time;

[0027] Step 3: Connect the upper grinding plate and the middle separator plate together, add abrasive to the circular liquid addition groove again, and the abrasive flows through the abrasive addition hole and the sector-shaped through hole on the middle separator plate to between the lower end surfaces of each lobe of the multi-lobe seal ring to be processed and the lower grinding surface of the lower grinding plate. Drive the upper grinding plate, then the upper grinding plate, the middle separator plate and each lobe of the multi-lobe seal ring to be processed all rotate around the core shaft, so that the lower grinding plate grinds the lower end surfaces of each lobe of the multi-lobe seal ring to be processed through its lower grinding surface for a preset time, and complete the double-end grinding of the multi-lobe seal ring.

[0028] Advantages of the present invention:

[0029] 1. A multi-lobe seal ring double-end grinding device for a liquid rocket engine provided by the present invention includes four parts: an upper grinding plate, a middle separator plate, a lower grinding plate and a core shaft. The multi-lobe seal ring to be processed is arranged in the sector-shaped through holes of the middle separator plate, and the upper and lower grinding surfaces of the upper grinding plate and the lower grinding plate are used to grind the axial two ends of each lobe, which greatly ensures the reliability of the product quality and provides an effective guarantee for the subsequent positioning reference.

[0030] 2. A multi-lobe seal ring double-end grinding device and method for a liquid rocket engine provided by the present invention can carry multiple lobes of the same multi-lobe seal ring to be processed each time. Compared with the traditional grinding method, it ensures the consistency of the dimensional and geometric tolerances of the products in the same batch, and greatly improves the production efficiency and quality.

[0031] 3. The multi-lobe seal ring double-end grinding device for liquid rocket engines provided by the present invention is simple and easy to use. It can be used for other similar products just by replacing the middle partition plate, and is easy to reuse and has strong popularization.

[0032] 4. For the multi-lobe seal ring double-end grinding device for liquid rocket engines provided by the present invention, a plurality of upper radial narrow grooves are arranged along the radial direction of the bottom surface of the upper grinding disc, and a plurality of lower radial narrow grooves are arranged along the radial direction of the top surface of the lower grinding disc. The upper radial narrow grooves and the lower radial narrow grooves can store grinding agents and also discharge grinding debris.

[0033] 5. For the multi-lobe seal ring double-end grinding device for liquid rocket engines provided by the present invention, a plurality of axial narrow grooves are arranged circumferentially around the outer wall of the core shaft, which can prevent excessive grinding powder and other impurities from entering between the core shaft and the upper and lower grinding discs, causing the core shaft to jam. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] Figure 1 is a schematic structural diagram of an embodiment of the multi-lobe seal ring double-end grinding device for liquid rocket engines of the present invention;

[0035] Figure 2 is the present invention Figure 1 radial sectional view;

[0036] Figure 3 is a bottom view of the upper grinding disc in the embodiment of the present invention;

[0037] Figure 4 is a radial sectional view of the upper grinding disc in the embodiment of the present invention;

[0038] Figure 5 is a schematic structural diagram of the middle partition plate in the embodiment of the present invention;

[0039] Figure 6 is a top view of the lower grinding disc in the embodiment of the present invention;

[0040] Figure 7 is a radial sectional view of the lower grinding disc in the embodiment of the present invention.

[0041] Reference Signs in the Drawings:

[0042] 1 - core shaft, 2 - upper grinding disc, 21 - annular liquid adding groove, 22 - grinding agent adding hole, 23 - upper radial narrow groove, 24 - upper circular protrusion, 3 - middle partition plate, 31 - sector-shaped through hole, 4 - lower grinding disc, 41 - lower radial narrow groove, 42 - lower circular protrusion, 5 - grinding handle, 6 - pin. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0043] The technical solution of the present invention will be clearly and completely described below in conjunction with the accompanying drawings and embodiments. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative work belong to the scope of protection of the present invention.

[0044] A multi-lobe seal ring double-end grinding device for a liquid rocket engine provided by an embodiment of the present invention, as Figure 1 and Figure 2 shown, the multi-lobe seal ring double-end grinding device includes a mandrel 1, and an upper grinding disc 2, a middle isolation plate 3, and a lower grinding disc 4 that are coaxially sleeved on the mandrel 1 in sequence from top to bottom;

[0045] As Figure 3 and Figure 4 shown, a downwardly concave annular liquid adding groove 21 is provided on the top surface of the upper grinding disc 2 around its circumference for adding grinding fluid as a medium during the grinding process; a plurality of abrasive adding holes 22 penetrating the upper and lower surfaces of the upper grinding disc 2 are provided at the bottom of the annular liquid adding groove 21, and the bottom surface of the upper grinding disc 2 is an upper grinding surface for grinding one end face in the axial direction of the multi-lobe seal ring to be processed; the upper grinding disc 2 and the middle isolation plate 3 are detachably connected by a pin 6; a plurality of upper spoke-shaped narrow grooves 23 are provided on the bottom surface of the upper grinding disc 2 along its radial direction; the number of the upper spoke-shaped narrow grooves 23 is equal to the number of the abrasive adding holes 22 in the annular liquid adding groove 21 and they are in one-to-one correspondence and communication for storing abrasive and discharging grinding chips. In other embodiments, a downward upper circular protrusion 24 is provided in the middle of the bottom surface of the upper grinding disc 2; the upper grinding surface is the lower surface of the upper circular protrusion 24. A grinding handle 5 is provided on the upper grinding disc 2; the grinding handle 5 is located on the circumferential outside of the upper circular protrusion 24, and the pin 6 is located on the circumferential outside of the upper circular protrusion 24 and is distributed at both ends of the same diameter of the upper grinding disc 2 as the grinding handle 5. In this embodiment, two circles of annular liquid adding grooves 21 are provided on the upper grinding disc 2, and four abrasive adding holes 22 are provided in each annular liquid adding groove 21; the four abrasive adding holes 22 in the two circles of annular liquid adding grooves 21 are in one-to-one correspondence along the radial direction of the upper grinding disc 2. During the grinding process, abrasive is added to the annular liquid adding groove 21, and the abrasive will flow into the upper spoke-shaped narrow grooves at the bottom of the upper grinding disc 2 along the abrasive adding holes 22 in the annular liquid adding groove 21, and the abrasive will be smeared on the top surface of the multi-lobe seal ring to be processed as the upper grinding disc 2 rotates.

[0046] As Figure 5 shown, a fan-shaped through hole 31 for placing each lobe of the multi-lobe seal ring to be processed is provided on the middle isolation plate 3, and the fan-shaped through hole 31 penetrates the upper and lower end faces of the middle isolation plate 3; the thickness of the middle isolation plate 3 is less than the target thickness of the multi-lobe seal ring to be processed; a plurality of axial narrow grooves are provided on the outer wall of the mandrel 1 around its circumference for accommodating abrasive or impurities to prevent jamming.

[0047] like Figure 6 and Figure 7 As shown, the upper end surface of the lower grinding disc 4 is the lower grinding surface, which is used to grind the other axial end surface of the multi-petal sealing ring to be processed. The top surface of the lower grinding disc 4 is provided with a plurality of lower spoke-shaped narrow grooves 41 along its radial direction, which are used to store abrasives and discharge grinding chips. In other embodiments, a lower circular protrusion 42 protruding upward is provided in the middle of the top surface of the lower grinding disc 4; the lower grinding surface is the upper surface of the lower circular protrusion 42. When grinding the bottom surface of the multi-petal sealing ring to be processed, the abrasive is injected along the annular liquid adding groove 21 of the upper grinding disc 2, and the abrasive flows down along the abrasive adding hole 22, and then flows along the slit of the middle isolation plate 3 (because the size of the middle isolation plate is slightly larger than the product) to the lower grinding disc 4, so that the abrasive addition to the lower grinding surface can be achieved.

[0048] After completing the holes, grooves and other external features of the upper grinding disc, middle isolation plate and lower grinding disc, they all undergo stress elimination and deformation removal processes such as aging and precision grinding to ensure the precision of the device.

[0049] The steps of grinding using the above-mentioned multi-petal sealing ring double-end surface grinding device for liquid rocket engines are as follows:

[0050] Step 1, sleeve the lower grinding disc 4 and the middle isolation plate 3 outside the core shaft 1 with the lower grinding surface of the lower grinding disc facing upward; then place each petal of the multi-petal sealing ring to be processed in each fan-shaped through hole 31 on the middle isolation plate 3; then sleeve the upper grinding disc 2 outside the core shaft 1 and place it on the top surface of the middle isolation plate 3 and each petal, so that its upper grinding surface faces downward;

[0051] Step 2, adding abrasive to the annular liquid adding groove 21, the abrasive flows through the abrasive adding hole 22 to between the upper grinding surface of the upper grinding disc 2 and the upper end surface of each petal of the multi-petal sealing ring to be processed, rotating the grinding handle 5, driving the upper grinding disc 2 to rotate around the core shaft 1, so that the upper grinding disc 2 grinds the upper end surface of each petal of the multi-petal sealing ring to be processed through its upper grinding surface for a preset time;

[0052] Step 3, connect the upper grinding disc 2 and the middle isolation plate 3 together through the pin 6, add abrasive to the annular liquid adding groove 21 again, and the abrasive flows to between the lower end surface of each petal of the multi-petal sealing ring to be processed and the lower grinding surface of the lower grinding disc 4 through the abrasive adding hole 22 and the fan-shaped through hole 31 on the middle isolation plate 3, and turn the grinding handle 5 to drive the upper grinding disc 2, so that the upper grinding disc 2, the middle isolation plate 3 and the petals of the multi-petal sealing ring to be processed all rotate around the core shaft 1, so that the lower grinding disc 4 grinds the lower end surface of each petal of the multi-petal sealing ring to be processed through its lower grinding surface for a preset time, thereby completing the double-end surface grinding of the multi-petal sealing ring.

[0053] The multi-piece seal ring double-end grinding device and method for liquid rocket engines provided in this embodiment carry multiple products each time. Compared with the traditional grinding method, it ensures the consistency of the dimensions and geometric tolerances of multi-piece ring products in the same batch, and greatly improves the production efficiency.

[0054] As described above, the above are only specific embodiments of the present invention, but the protection scope of the present invention is not limited thereto. Any changes or substitutions within the technical scope disclosed in the present invention should be covered within the protection scope of the present invention. Therefore, the protection scope of the present invention should be subject to the protection scope of the claimed rights.

Claims

1. A multi - lobe seal ring double - end grinding device for a liquid rocket engine, characterized in that: It includes a mandrel (1), an upper grinding disc (2), a middle isolation plate (3), and a lower grinding disc (4) that are coaxially sleeved on the mandrel (1) in sequence from top to bottom; The top surface of the upper grinding disc (2) is provided with a circumferentially downward - sunken annular liquid - adding groove (21) around its circumference. The bottom of the annular liquid - adding groove (21) is provided with a plurality of abrasive - adding holes (22) penetrating through the upper and lower surfaces of the upper grinding disc (2). The bottom surface of the upper grinding disc (2) is an upper grinding surface for grinding one axial - end face of the multi - lobe seal ring to be processed; The upper grinding disc (2) is detachably connected to the middle isolation plate (3); The middle isolation plate (3) is provided with fan - shaped through - holes (31) for placing each lobe of the multi - lobe seal ring to be processed. The fan - shaped through - holes (31) penetrate through the upper and lower end faces of the middle isolation plate (3); The thickness of the middle isolation plate (3) is less than the target thickness of the multi - lobe seal ring to be processed; The upper end surface of the lower grinding disc (4) is a lower grinding surface for grinding the other axial - end face of the multi - lobe seal ring to be processed.

2. The multi - lobe seal ring double - end grinding device for a liquid rocket engine according to claim 1, characterized in that: The bottom surface of the upper grinding disc (2) is provided with a plurality of upper - spoke - shaped narrow grooves (23) along its radial direction; The number of the upper - spoke - shaped narrow grooves (23) is equal to the number of the abrasive - adding holes (22) in the annular liquid - adding groove (21) and they are in one - to - one corresponding communication for storing abrasive and discharging grinding chips.

3. The multi - lobe seal ring double - end grinding device for a liquid rocket engine according to claim 1 or 2, characterized in that: The top surface of the lower grinding disc (4) is provided with a plurality of lower - spoke - shaped narrow grooves (41) along its radial direction for storing abrasive and discharging grinding chips.

4. The multi - lobe seal ring double - end grinding device for a liquid rocket engine according to claim 3, characterized in that: A plurality of axial narrow grooves are provided around the circumference of the outer wall of the mandrel (1) for accommodating abrasive or impurities to prevent jamming.

5. The multi - lobe seal ring double - end grinding device for a liquid rocket engine according to claim 4, characterized in that: The middle of the bottom surface of the upper grinding disc (2) is provided with a downward - protruding upper circular protrusion (24); The upper grinding surface is the lower surface of the upper circular protrusion (24).

6. The multi - lobe seal ring double - end grinding device for a liquid rocket engine according to claim 5, characterized in that: The middle of the top surface of the lower grinding disc (4) is provided with an upward - protruding lower circular protrusion (42); The lower grinding surface is the upper surface of the lower circular protrusion (42).

7. The multi - lobe seal ring double - end grinding device for a liquid rocket engine according to claim 6, characterized in that: A grinding handle (5) is provided on the upper grinding disc (2); The grinding handle (5) is located on the circumferential outer side of the upper circular protrusion (24).

8. The multi - lobe seal ring double - end grinding device for a liquid rocket engine according to claim 7, characterized in that: The upper grinding disc (2) and the middle isolation plate (3) are detachably connected by a pin (6); The pin (6) is located on the circumferential outer side of the upper circular protrusion (24), and is distributed at both ends of the upper grinding plate (2) and the grinding handle (5) on the same diameter.

9. The multi-lobe seal ring double-end grinding device for a liquid rocket engine according to claim 8, characterized in that: Two circular liquid adding grooves (21) are provided on the upper grinding plate (2), and four abrasive adding holes (22) are provided in each circular liquid adding groove (21); the four abrasive adding holes (22) in the two circular liquid adding grooves (21) correspond to each other along the radial direction of the upper grinding plate (2).

10. A multi-lobe seal ring double-end grinding method for a liquid rocket engine, using the multi-lobe seal ring double-end grinding device for a liquid rocket engine according to any one of claims 1-9, characterized in that, It includes the following steps: Step 1: Sheath the lower grinding plate (4) and the middle separator (3) outside the core shaft (1) with the lower grinding surface of the lower grinding plate facing upwards; then place the respective petals of the multi-lobe seal ring to be processed in the respective sector-shaped through holes (31) on the middle separator (3); then sheath the upper grinding plate (2) outside the core shaft (1) and place it on the top surfaces of the middle separator (3) and the respective petals, with its upper grinding surface facing downwards. Step 2: Add abrasive to the circular liquid adding groove (21), and the abrasive flows through the abrasive adding hole (22) to between the upper grinding surface of the upper grinding plate (2) and the upper end surfaces of the respective petals of the multi-lobe seal ring to be processed, drive the upper grinding plate (2) to rotate around the core shaft (1), so that the upper grinding plate (2) grinds the upper end surfaces of the respective petals of the multi-lobe seal ring to be processed through its upper grinding surface and the abrasive for a preset time. Step 3: Connect the upper grinding plate (2) and the middle separator (3) together, add abrasive to the circular liquid adding groove (21) again, and the abrasive flows through the abrasive adding hole (22) and the sector-shaped through holes (31) on the middle separator (3) to between the lower end surfaces of the respective petals of the multi-lobe seal ring to be processed and the lower grinding surface of the lower grinding plate (4), drive the upper grinding plate (2), then the upper grinding plate (2), the middle separator (3) and the respective petals of the multi-lobe seal ring to be processed all rotate around the core shaft (1), so that the lower grinding plate (4) grinds the lower end surfaces of the respective petals of the multi-lobe seal ring to be processed through its lower grinding surface for a preset time, and the double-end grinding of the multi-lobe seal ring is completed.

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