A solid rocket engine ground test integrated test stand

Abstract

The application provides a solid rocket engine ground test integral test frame, which comprises a bracket assembly 1, a movable frame platform 2, a limiting assembly 3 and a fixed frame platform 4; the fixed frame platform comprises two support assemblies, the support assemblies are provided with ball assemblies, the two fixed frame platforms 4 are symmetrically arranged, and the lateral force resistance capacity is enhanced; the fixed frame platform is located between the four bracket assemblies and is fixedly connected; the bracket assembly comprises a support body, two wheel shaft combinations are fixed on the support body along the horizontal and vertical directions, the rolling surfaces of the wheel shaft combinations are respectively in contact with the top wall and the side wall of the movable frame platform 2; the bottom of the movable frame platform is in contact with the ball assembly of the fixed frame platform; a plurality of limiting assemblies 3 are further arranged, the top end of the limiting assembly abuts against the bottom of the movable frame platform, and the bottom end is fixed on the outer wall of the ball assembly. The profile steel is assembled into an integral type, the test process steps are simplified, the ball / roller structure makes the contact surfaces realize point contact, the friction force is small, the thrust measurement precision is high, and the universality is strong.

Description

Technical Field

[0001] This invention belongs to the field of rocket engine testing, specifically relating to an integrated test rig for ground testing of solid rocket engines. Background Technology

[0002] Engine ground testing utilizes small displacement elements to provide degrees of freedom along the engine's axial direction, minimizing thrust transmission losses and aiming to obtain more realistic engine energy characteristics. However, during combined testing of large engines with nozzle oscillation, the oscillation causes significant lateral forces in other directions alongside the main thrust, posing substantial safety hazards during the testing and measurement process.

[0003] Existing technologies mostly employ split-type test frames, with most structures only capable of single-stage lateral force performance testing by being fixed to the ground. Due to the complex and unique structure of split-type test frames, it is difficult to lift and move the device at the center of gravity, increasing installation difficulty. Furthermore, a single test frame requires at least four sets of single-stage lateral force bearing devices for fixation, and the installation of each lateral force bearing structure causes a shift in the test frame's axis, resulting in a significant difference between the measured engine thrust data and the actual thrust. In addition, the design time for split-type structures is long, which cannot meet the ever-increasing demands of testing tasks.

[0004] Patent CN202123283253.9 discloses an integrated testing fixture for solid rocket motors. This integrated fixture addresses the limitations of existing testing frames, which have long processing cycles and cannot meet the demands of current demanding testing tasks. However, this fixture is suitable for engines with lower accuracy requirements. During long-engine ground testing, the engine is held in place by a front and rear center frame. Under high internal engine pressure, the center frame can damage the engine casing, potentially affecting test safety. Furthermore, adjusting the front and rear center frames at the engine's center height presents difficulties. During testing, the center frame is restricted to the engine via rollers, limiting its freedom to the thrust axis. The line contact between the rollers and the engine results in high friction and low testing accuracy. Additionally, the center frame is bolted to the base plate. If the lateral force exceeds the bolt breakage limit, the center frame may break and detach, causing a safety hazard. Summary of the Invention

[0005] To address the problem of low lateral resistance in existing ground-based joint test devices for solid rocket engines, which leads to low accuracy in engine thrust data measurement, this invention provides an integrated test rig for ground-based solid rocket engine testing.

[0006] The technical solution adopted in this invention is: an integrated test frame for ground testing of solid rocket engines, comprising a bracket assembly 1, a moving frame platform 2, a limiting assembly 3, and a fixed frame platform 4;

[0007] Two fixed frame platforms 4 are symmetrically arranged. Each fixed frame platform includes two support components. A ball bearing assembly 401 is installed on the support components. The two support components are fixedly connected to each other.

[0008] The fixed frame platform is located between four symmetrically arranged bracket components and is fixedly connected to bracket component 1;

[0009] The bracket assembly includes a support body, on which two wheel and axle assemblies are fixed along the horizontal and vertical directions, and the rolling surfaces of the wheel and axle assemblies contact the top wall and side wall of the moving frame platform 2, respectively.

[0010] The moving frame platform 2 is located above the fixed frame platform 4, and its bottom is in contact with the ball assembly 401 of the fixed frame platform;

[0011] Multiple limiting components 3 are provided between the moving frame platform and the fixed frame platform. The top of the limiting components abuts against the bottom of the moving frame platform 2, and the bottom is fixed to the outer wall of the ball assembly 401.

[0012] Furthermore, the wheel and axle assembly includes an adjusting screw 10201, an adjusting sleeve 10203, and a roller assembly 10206; the shaft section of the roller assembly 10206 is installed in the cavity of the adjusting sleeve 10203 and is radially locked by a locking member; one end of the adjusting screw 10201 is fixed outside the adjusting sleeve 10203, and the other end is located in the cavity of the adjusting sleeve and the shaft section of the roller assembly.

[0013] Furthermore, a lifting ring 101 is provided at the top of the bracket assembly.

[0014] Furthermore, the moving frame platform includes a frame body 205, an upper panel 201, quenched side plates 203, and a quenched bottom plate 208; the frame body 205 is welded from structural steel, with quenched side plates 203 fixedly installed on the outer sides at both ends, and a quenched bottom plate 208 installed at the bottom.

[0015] Furthermore, the top of the frame body is provided with multiple T-shaped grooves 202, and the upper panel 201 is provided with strip-shaped holes at positions corresponding to the T-shaped grooves of the frame body.

[0016] Furthermore, the quenched side plate 203 is fixedly connected to the side wall of the frame body 205 through a back plate 204, which is located inside the side wall of the frame body.

[0017] Furthermore, a lower mounting plate 207 is also installed between the bottom of the frame body 205 and the quenching base plate 208.

[0018] Furthermore, a plurality of I-shaped horizontal ribs 206 are provided between the top and bottom of the frame body 205.

[0019] Furthermore, the ball assembly 401 includes a slide 40101, a guide member, a steel ball 40104, a spring 40107, and a guide rod 40108; the slide 40101 has an internal cavity, the guide member is disposed in the slide cavity, the two ends of the steel ball are respectively restricted in the channel of the guide member by the guide rod 40108, and the spring 40107 is fitted on the guide rod; the diameter of the steel ball is greater than the height of the slide cavity and contacts the bottom of the slide, and the steel ball is fitted with the inner wall of the guide member channel with a small clearance.

[0020] Furthermore, the limiting component includes a limiting plate 301 and a limiting bolt 302; one end of the limiting plate is attached to the bottom of the moving frame platform 2, and the other end is connected to the side wall of the ball assembly on the fixed frame platform 4 through the limiting bolt 302.

[0021] The beneficial effects of this invention are:

[0022] 1. This invention integrates the test platform into a whole through assembly, enabling overall hoisting. This solves the problem of the process of modifying the test platform according to the engine structure before each test for split test frames, greatly shortening the test preparation time and improving the test efficiency.

[0023] 2. The present invention uses a ball / roller structure as a small displacement element of the test platform, so that the test moving frame platform and the engine mounting platform are connected by point contact between the ball and the plane, resulting in less friction and higher accuracy of engine test thrust measurement.

[0024] 3. Unlike existing lateral load-bearing devices composed of welded components, this invention adopts a steel frame structure, which reduces weight, increases strength, enhances the test platform's resistance to lateral forces, and reduces the space occupied by the lateral load-bearing device. This achieves high strength and miniaturization of the integrated test frame, meeting the requirements for rapid installation of test frames for various structural assessment tests of medium and large engines. It also shortens the test preparation cycle, reduces labor intensity, and improves test efficiency and capabilities.

[0025] 4. By integrally welding two fixed frame platforms onto the base plate as lateral force bearing devices, the present invention not only eliminates the process step of axis adjustment, but also enhances the lateral force resistance capability of the present invention.

[0026] 5. The original split-type test frame required adjustments to the installation position of the high-rigidity web plate based on the specific support position of the lower platform. Before each test or process adjustment, the platform had to be disassembled, the web plate installation position adjusted to meet test requirements, and finally the test frame reassembled and the arc seat installed, resulting in a complex installation process. However, the integrated test frame of this invention eliminates the frequent web plate position adjustments, significantly shortening the process adjustment time and simplifying the testing procedure.

[0027] 6. This invention is applicable to structural tests, joint tests, and interstage separation tests of solid rocket engines with a main thrust of less than 150 tons, a diameter of no more than 2000 mm, a lateral force of no more than 20 tons, and a weight of no more than 50 tons, with the main thrust being less than 150 tons. It is not limited to situations where lateral forces exist during engine tests due to nozzle oscillation, servo motor oscillation, or other similar phenomena. It enables engine thrust measurement with accuracy meeting test requirements, has a wide range of applications, and is highly versatile. Attached Figure Description

[0028] Figure 1 This is a schematic diagram of the integral test frame structure of the present invention;

[0029] Figure 2 yes Figure 1 The main view;

[0030] Figure 3 yes Figure 1 Schematic diagram of the middle bracket assembly;

[0031] Figure 4 yes Figure 3 Schematic diagram of the central wheel axle assembly structure;

[0032] Figure 5 yes Figure 1 Schematic diagram of the intermediate frame platform structure;

[0033] Figure 6 yes Figure 5 The main view;

[0034] Figure 7 yes Figure 1 Schematic diagram showing the coordination between the middle limiting structure and the moving frame platform and the fixed frame platform;

[0035] Figure 8 yes Figure 1 Schematic diagram of the central frame platform structure;

[0036] Figure 9 yes Figure 8 Schematic diagram of the middle rolling ball assembly;

[0037] Figure 10 This is a schematic diagram of a single long integral test rack in use;

[0038] Figure 11 This is a schematic diagram of the combined use of short, integrated test racks;

[0039] Figure 12 It is a combination of multiple integrated test racks.

[0040] Explanation of reference numerals in the attached drawings: 1-Cower assembly, 101-Lifting ring, 102-Wheel and axle assembly, 10201-Adjusting screw, 10202-Restricting ring, 10203-Adjusting sleeve, 10204-Anti-rotation pin, 10205-Rotation limiting screw, 10206-Roller assembly, 103-Support body, 104-Small rib, 2-Moving frame platform, 201-Top panel, 202-T-slot, 203-Quenched side plate, 204-Back plate, 205-Frame body, 206-Horizontal Rib, 207-lower mounting plate, 208-quenched base plate, 3-limiting assembly, 301-limiting plate, 302-limiting bolt, 4-fixed frame platform, 401-ball assembly, 40101-slide block, 40102-ball sleeve, 40103-guide plate, 40104-steel ball, 40105-base plate, 40106-anti-detachment pin, 40107-spring, 40108-guide rod, 402-support assembly, 403-connector, 404-platform base plate. Detailed Implementation

[0041] The present invention will now be described in further detail with reference to the accompanying drawings and specific embodiments.

[0042] An integrated test rig for ground testing of solid rocket motors includes a bracket assembly 1, a moving platform 2, a limiting assembly 3, and a fixed platform 4; the bracket assemblies are symmetrically and vertically arranged at both ends of the fixed platform 4, the limiting assembly 3 is symmetrically installed on the top of the fixed platform 4, and the moving platform 2 is located on the limiting assembly.

[0043] Reference Figure 2 The bracket assembly 3 primarily bears the lateral forces of the entire test frame during testing. The bracket structure 3 is symmetrically and vertically welded to the base plate of the fixed platform 4. The bracket assembly includes a lifting ring 101, a wheel and axle assembly 102, a support body 103, and reinforcing ribs 104. The support body 103 indirectly bears the lateral forces generated by the engine and is constructed from welded steel sections. Two diagonal ribs are provided on the inner side of the support body to increase the strength and rigidity of the bracket assembly and restrict the pitch, yaw, roll, radial, and axial degrees of freedom of the entire moving platform 2. The reinforcing ribs 104 are welded to the lower end of the support body and the base plate of the fixed platform 4, increasing the weld area and improving the structural strength of the integral test frame. The upper end of the support body 103 is a cantilever beam, with a lifting ring 101 at the fixed end for lifting and transporting the integral test frame structure.

[0044] Reference Figure 3The wheel and axle assembly 102 comprises two parts: one vertically fixed below the cantilever end of the cantilever beam of the support body 103, and the other horizontally fixed inside the vertical support plate of the support body 103. The wheel and axle assembly 102 directly bears the lateral force generated by the engine and has high strength and rigidity. The wheel bodies in the wheel and axle assembly contact the top wall and side wall of the moving frame platform 2 respectively, for pressing the moving frame platform 2. Since the moving frame platform 2 is pressed against by the wheel and axle assembly in the engine yaw and pitch directions, but the wheels of the wheel and axle assembly can provide directional rolling, the entire moving frame platform 2 has a degree of freedom only in the direction of the engine thrust axis.

[0045] Reference Figure 4 The wheel and axle assembly includes an adjusting screw 10201, a limiting ring 10202, an adjusting sleeve 10203, an anti-rotation pin 10204, a rotation-limiting screw 10205, and a roller assembly 10206. The shaft section of the roller assembly 10206 is installed inside the adjusting sleeve 10203. The adjusting screw 10201 is sequentially installed in the cavity of the adjusting sleeve 10203 and the roller assembly shaft section via the limiting ring 10202 and the anti-rotation pin 10204, and is radially connected by the rotation-limiting screw 10205. The anti-rotation pin 10204, the rotation-limiting screw 10205, and the limiting ring 10202 ensure that the wheel and axle assembly 102 can only move unidirectionally in the adjusting direction. Under the action of the adjusting screw 10201, the roller assembly 10206 can move along the axis of the adjusting sleeve 10203, realizing the adjustment and clamping of the moving frame platform. During the acceptance of the test frame, the extension length of the adjusting wheel axle assembly 102 is measured to ensure that the extension lengths of the four wheel axle assemblies 102 that hold the moving frame platform 2 are equal, thus completing the alignment of the test frame's own axis. During the test, no further adjustment is required, greatly reducing the process preparation time.

[0046] The wheel body in the wheel and axle assembly has high rigidity and will not deform under large lateral forces, which enables the test frame to be used for a long time or reduce maintenance.

[0047] Reference Figure 3The moving frame platform 2 is the direct load-bearing component for the engine's weight and also the main moving part of the integral test frame. The moving frame platform includes an upper panel 201, hardened side plates 203, a back plate 204, a frame body 205, horizontal ribs 206, a lower mounting plate 207, and a hardened base plate 208. The hardened side plates 203 and the hardened base plate 208 are the moving surfaces of the moving frame platform, possessing high hardness and exhibiting high strength and rigidity in all directions. The frame body 205 is constructed from welded steel sections, with a T-slot 202 made of steel sections at the top. The upper panel 201 is mounted on the top of the frame body 205 for mounting the engine's arc seat. Multiple elongated holes are formed on the upper panel and welded to the open ends of the T-slots, allowing for the fixing of the upper panel and the arc seat mounting surface using T-bolts and nuts. Multiple I-shaped horizontal ribs 206 are set in the frame cavity, vertically located between the top and bottom of the frame, to enhance the ability of the moving frame platform to resist various moments in the pitch, yaw and roll directions.

[0048] Since steel plates are difficult to weld after quenching, back plates 204 are welded to the inner sides of both ends of the frame body 205. Quenched side plates 203 are located on the outer sides of both ends of the frame body and are connected to the side walls of the frame body and the back plates 204 as a whole through countersunk holes and hex socket screws. The quenched side plates 203 are made of heat-treated carbon steel, which has high hardness, ensuring that the lateral movement surface of the moving frame platform is a high-hardness surface.

[0049] A set of web plate assemblies is welded to both ends of the bottom of the frame 205. The web plate assembly includes a lower mounting plate 207 and a quenched base plate 208, which are connected by bolts. This ensures the hardness of the moving surface under the moving frame platform and increases the thickness of the web plate assembly, avoiding problems such as excessive friction or thrust spikes in the steel balls of the fixed frame platform 4 caused by web plate deformation. Since current processing technology cannot complete the heat treatment of plates that are long, narrow, and thin, the quenched base plate 208 and the quenched side plate 203 are composed of multiple short steel plates, which are spliced ​​together after heat treatment.

[0050] Reference Figure 4 The limiting assembly 3 includes a limiting plate 301 and a limiting bolt 302. The limiting assembly is installed between the moving frame platform 2 and the fixed frame platform 4. The limiting plate 301 is L-shaped and is fixed to the outer wall of the slide block 401 of the top ball bearing assembly of the fixed frame platform 4 by the limiting bolt 302. It is used to limit the vertical movement of the moving frame platform 2 and ensure the safety of the integral test frame during hoisting and transportation.

[0051] Reference Figure 5The fixed platform 4 serves as the load-bearing foundation for the entire test frame, while two fixed platforms are located at the bottom of the moving platform 2. The fixed platform 4 includes two ball bearing assemblies 401, two support assemblies 402, a connector 403, and a platform base plate 404. The two support assemblies 402 are symmetrically and vertically arranged on the platform base plate 404, and the connector 403 is fixed between the two support assemblies 402, connecting them into a single unit. The ball bearing assemblies 401 are located at the top of the support assemblies, directly bearing the engine load. The support assemblies transfer the load to the test frame mounting platform via the platform base plate 404.

[0052] Reference Figure 6 The ball assembly includes a slide block 40101, a ball sleeve 40102, a guide plate 40103, a steel ball 40104, a base plate 40105, an anti-detachment pin 40106, a spring 40107, and a guide rod 40108. The slide block 40101 has an internal cavity to accommodate other components and provide direction for the steel ball's movement. The ball sleeve 40102 is fitted inside the slide block cavity, and the guide plate 40103 is located on its side wall. The guide plate and the slide block base plate 40105 form a channel for the steel ball's movement. The steel ball 40104 is a standard steel ball with high hardness. The diameter of the steel ball is larger than the height of the slide block cavity. The steel ball is installed inside the cavity. The slide block base plate 40105 is in direct contact with the steel ball, while the inner wall of the guide plate 40103 does not contact the steel ball, leaving a gap to facilitate the movement of the steel ball and to allow for small displacements during operation, avoiding any impact on thrust measurement during movement.

[0053] Guide rods 40108 are symmetrically installed on another set of side walls of the ball sleeve 40102. Springs 40107 are fitted on the guide rods. Anti-disengagement pins 40106 are installed at one end of the guide rods to prevent the guide rods from coming out of the mounting holes on the side walls of the ball sleeve. The other end of the guide rods has a square end face and rests against the steel ball. The guide rods and springs are used to control the steel ball to be located in the middle of the ball sleeve. Under the action of the springs and guide rods, the steel ball can move along the length of the guide plate.

[0054] Reference Figure 11 In this invention, the two slides on the fixed platform 4 can be designed as one unit according to the test requirements, and the slide cavity is divided into two chambers by a ball sleeve.

[0055] The installation process for conducting solid rocket motor tests using the device of the present invention specifically includes the following steps:

[0056] Step 1: Secure the integral test frame with limit bolts.

[0057] Step 2: Use the lifting rings on the bracket assembly to lift the integral test frame onto the transfer vehicle and transport it to the test bench.

[0058] Step 3: Arrange the test frame according to the testing process. The device of this invention allows for the use of a single long integral test frame, a combination of short integral test frames, or a combination of multiple integral test frames. Two arc seats can be placed on an integral test frame with a long mounting platform to meet the requirements of single-platform installation for short engines; or an integral test frame with multiple short mounting platforms can be used to meet the installation requirements of multiple support points for longer engines. The integral test frame of this invention allows for free adjustment of the entire testing process according to the engine length.

[0059] This invention utilizes the rollers of the bracket assembly 1 and the steel balls of the fixed platform 4 to restrict the pitch, yaw, roll, radial, and tangential movements of the moving platform 2, retaining only the axial degree of freedom of the engine. Rolling friction is used to reduce thrust transmission loss. The fixed platform 4 serves as the overall support for the test frame, fixing the moving platform 2 at a certain height. The lifting rings on the bracket assembly enable the hoisting and transport of the integral test frame. Before hoisting, the limiting assembly 3 is used to limit the moving platform along the engine axis to ensure hoisting safety. During actual use, the limiting assembly is released, allowing the integral test frame to have freedom along the engine axis.

Claims

1. An integral test stand for ground testing of solid rocket motors, characterized in that, It includes a bracket assembly (1), a moving frame platform (2), a limiting assembly (3), and a fixed frame platform (4); Two fixed platforms (4) are symmetrically arranged. Each fixed platform includes two support components. A ball bearing assembly (401) is installed on the support components. The two support components are fixedly connected. The fixed frame platform is located between four symmetrically arranged bracket components and is fixedly connected to the bracket component (1); The bracket assembly includes a support body, on which two wheel and axle assemblies are fixed along the horizontal and vertical directions, and the rolling surfaces of the wheel and axle assemblies are in contact with the top wall and side wall of the moving frame platform (2), respectively. The moving frame platform (2) is located above the fixed frame platform (4), and its bottom is in contact with the ball assembly (401) of the fixed frame platform; Multiple limiting components (3) are provided between the moving frame platform and the fixed frame platform. The top of the limiting components abuts against the bottom of the moving frame platform (2), and the bottom is fixed to the outer wall of the ball assembly (401).

2. The integrated test rig for ground testing of solid rocket motors as described in claim 1, characterized in that, The wheel and axle assembly includes an adjusting screw (10201), an adjusting sleeve (10203), and a roller assembly (10206); the shaft section of the roller assembly (10206) is installed in the cavity of the adjusting sleeve (10203) and is radially locked by a locking member; one end of the adjusting screw (10201) is fixed outside the adjusting sleeve (10203), and the other end is located in the cavity of the adjusting sleeve and the shaft section of the roller assembly.

3. The integrated test rig for ground testing of solid rocket motors as described in claim 2, characterized in that, The top of the bracket assembly is provided with a lifting ring (101).

4. The integrated test rig for ground testing of solid rocket motors as described in claim 1, characterized in that, The moving frame platform includes a frame body (205), a top panel (201), quenched side plates (203), and a quenched bottom plate (208). The frame body (205) is welded from structural steel, with quenched side plates (203) fixedly installed on the outer sides at both ends, and a quenched bottom plate (208) installed at the bottom.

5. The integrated test rig for ground testing of solid rocket motors as described in claim 4, characterized in that, The top of the frame is provided with multiple T-slots (202), and the upper panel (201) is provided with strip holes at positions corresponding to the T-slots of the frame.

6. The integrated test rig for ground testing of solid rocket motors as described in claim 5, characterized in that, The quenched side plate (203) is fixedly connected to the side wall of the frame body (205) through a back plate (204), and the back plate (204) is located inside the side wall of the frame body.

7. The integrated test rig for ground testing of solid rocket motors as described in claim 6, characterized in that, A lower mounting plate (207) is also installed between the bottom of the frame body (205) and the quenching base plate (208).

8. The integrated test rig for ground testing of solid rocket motors as described in claim 7, characterized in that, Multiple I-shaped horizontal ribs (206) are also provided between the top and bottom of the frame body (205).

9. The integrated test rig for ground testing of solid rocket motors as described in claim 1, characterized in that, The ball assembly (401) includes a slide (40101), a guide, a steel ball (40104), a spring (40107), and a guide rod (40108). The slide (40101) has a cavity inside, and the guide is set inside the slide cavity. The two ends of the steel ball are respectively restricted in the channel of the guide by the guide rod (40108). The spring (40107) is fitted on the guide rod. The diameter of the steel ball is greater than the height of the slide cavity and contacts the bottom of the slide. The steel ball is fitted with the inner wall of the guide channel with a small clearance.

10. The integrated test rig for ground testing of solid rocket motors as described in claim 1, characterized in that, The limiting component includes a limiting plate (301) and a limiting bolt (302); one end of the limiting plate is attached to the bottom of the moving frame platform (2), and the other end is connected to the side wall of the ball assembly on the fixed frame platform (4) through the limiting bolt (302).

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