Solid rocket booster containing heat insulation coating

Abstract

The utility model relates to the technical field of boosters, in particular to a solid rocket booster containing a heat insulation coating, which comprises a push rod, a front top cover, an ignition device, a powder blocking ring, a powder column, a combustion chamber shell, a spray pipe, a blanking cap and the heat insulation coating, the push rod is inserted into the head of the front top cover, and the push rod and the front top cover are in clearance fit; the front top cover is in threaded connection with the combustion chamber shell; the ignition device is in threaded connection with the front top cover; the medicine blocking rings are arranged on the front end face and the rear end face of the grain respectively, and the medicine blocking rings are in interference fit with the grain. The grain front end medicine blocking ring is limited by the threaded end face of the front top cover, and the grain tail medicine blocking ring is limited by the threaded end face of the spray pipe. The spray pipe is in threaded connection with the combustion chamber shell; the blanking cap is arranged at an outlet of the spray pipe; the heat insulation coating is sprayed and cured on the inner wall of the combustion chamber shell. The booster provided by the utility model not only can effectively insulate heat, but also can shorten the product development period and reduce the product cost.

Description

Technical Field

[0001] The utility model relates to the technical field of boosters, and particularly relates to a solid rocket booster with an adiabatic coating. Background Art

[0002] Due to its simple and reliable structure and convenient use, solid rocket boosters have been widely used in the take-off of various unmanned aerial vehicles (UAVs) and target drones. A solid rocket booster generally consists of a combustion chamber, a nozzle, an ignition device and affiliated parts. When the solid rocket booster works, the combustion chamber needs to withstand high-temperature and high-pressure gas, so the inner wall of the combustion chamber can resist high-temperature ablation.

[0003] The existing boosters are to increase the wall thickness of the combustion chamber or paste a layer of thermal insulation layer on the inner wall of the combustion chamber. The thermal insulation layer is generally made of rubber materials or other non-metallic materials with good high-temperature heat insulation performance.

[0004] Increasing the wall thickness of the combustion chamber will correspondingly increase the negative mass of the booster. Pasting a layer of thermal insulation layer on the inner wall of the combustion chamber has a long production cycle and high cost. These two existing technologies cannot meet the requirements of low-cost and rapid research and development of short-time solid rocket engines for the take-off power of UAVs and target drones. Summary of the Invention

[0005] In order to solve the above technical problems, one of the purposes of the utility model is to provide a solid rocket booster with an adiabatic coating to solve the problems that the existing boosters cannot meet the requirements of low-cost and rapid research and development of short-time solid rocket engines for the take-off power of UAVs and target drones, etc.

[0006] Based on the same inventive concept, the utility model also provides a solid rocket booster with an adiabatic coating, including: a push rod 1, which is inserted into the head of the front top cover with a clearance fit between them; a front top cover 2, which is threadedly connected to the combustion chamber shell; an ignition device 3, which is threadedly connected to the front top cover. After the external thread of the ignition device is coated with thread sealant, it is screwed into the threaded hole at the center of the inner wall of the front top cover; a medicine retaining ring 6, which is respectively arranged at the front and rear end faces of the propellant charge, and the medicine retaining ring has an interference fit with the propellant charge; a propellant charge 4, the front medicine retaining ring of the propellant charge is limited by the threaded end face of the front top cover, and the rear medicine retaining ring of the propellant charge is limited by the threaded end face of the nozzle; a combustion chamber shell 5, the inner wall of the combustion chamber shell is coated with an adiabatic coating 9, and the threaded positions at the front and rear ends of the combustion chamber shell need to be protected to prevent foreign matters such as coating residues from remaining; a nozzle 8, which is threadedly connected to the combustion chamber shell; a plug 7, which is placed at the outlet of the nozzle; the adiabatic coating 9 is sprayed and cured on the inner wall of the combustion chamber shell, and the inner threads of the front and rear openings of the combustion chamber shell should be avoided when spraying the adiabatic coating.

[0007] Furthermore, a sealing ring is arranged at the connection part between the front top cover and the combustion chamber shell.

[0008] Further, a sealing ring is provided at the connection part between the nozzle and the combustion chamber housing.

[0009] Further, the medicine retaining rings are respectively arranged on the front and rear end faces of the grain, and buffer pads are provided on the medicine retaining rings.

[0010] Further, the front and rear end faces of the grain are subjected to limited combustion treatment, and only the inner hole and the outer cylindrical surface are retained as the burning surface.

[0011] Further, the surface of the coating film of the heat-insulating coating 9 is flat, and pinholes, cracks and air bubbles are not allowed.

[0012] Further, after the wire of the ignition device is led out of the plug cover, the inner hole of the plug cover is filled with glue.

[0013] Further, the wire of the ignition device is led out to the tail of the booster through the inner hole of the grain, the throat of the nozzle and the inner hole of the plug cover.

[0014] Further, after the external thread at the tail of the nozzle is coated with thread glue, the plug cover is screwed onto the nozzle outlet.

[0015] Further, the heat-insulating coating 9 adopts a GT401 coating, and the coating thickness is 0.4 mm to 0.5 mm.

[0016] One or more of the above technical solutions of the present utility model have at least one or more of the following technical effects:

[0017] The present utility model provides a solid rocket booster with a heat-insulating coating, which can not only effectively insulate heat, but also shorten the product development cycle and reduce the product cost. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 : Structural schematic diagram of a solid rocket booster with a heat-insulating coating;

[0019] Figure 2 : Enlarged schematic diagram of the heat-insulating coating at position I;

[0020] Figure 3 : Enlarged schematic diagram of the front top cover limit at position II;

[0021] Figure 4 : Enlarged schematic diagram of the nozzle limit at position III;

[0022] Figure 5 : Test run thrust-time curve graph;

[0023] Wherein: 1 - push rod, 2 - front top cover, 3 - ignition device, 4 - grain, 5 - combustion chamber housing, 6 - medicine retaining ring, 7 - plug cover, 8 - nozzle, 9 - heat-insulating coating, 10 - sealing ring. DETAILED IMPLEMENTATION MANNER

[0024] The utility model provides a solid rocket motor with an adiabatic coating for a short time, which is used for the take-off power of an unmanned aerial vehicle and a target drone. The solid rocket motor includes a push rod, a front top cover, an ignition device, a grain, a combustion chamber shell, a grain stop ring, a plug, a nozzle, and an adiabatic coating. Among them, one sealing ring 10 is provided at each of the connection parts between the front top cover and the combustion chamber shell and between the nozzle and the combustion chamber shell, and one grain stop ring is provided at each of the front and rear end faces of the grain. The grain stop ring is provided with a buffer pad.

[0025] Before the assembly of the booster, the adiabatic coating needs to be first sprayed and cured on the inner wall of the combustion chamber shell. When spraying the adiabatic coating, the internal threads at the front and rear openings of the combustion chamber shell should be avoided. The ignition device is threadedly connected to the front top cover. After the external thread of the ignition device is coated with thread sealant, it is screwed into the threaded hole at the center of the inner wall of the front top cover. The front top cover is threadedly connected to the combustion chamber shell. After a sealing ring is sleeved on the root of the external thread where the front top cover and the combustion chamber shell are butted, the front top cover is screwed into the front opening of the combustion chamber. Limited combustion treatment is carried out on the front and rear end faces of the grain, and only the inner hole and the outer cylindrical surface are reserved as the burning surface. Two grain stop rings are respectively installed on the front and rear end faces of the grain, and the grain stop ring and the grain are in interference fit. The grain with the grain stop ring installed is inserted into the combustion chamber shell from the rear opening of the combustion chamber shell, and the front grain stop ring of the grain is limited by the threaded end face of the front top cover. The nozzle is threadedly connected to the combustion chamber. After a sealing ring is sleeved on the root of the external thread where the nozzle and the combustion chamber shell are butted, the nozzle is screwed into the rear opening of the combustion chamber, and the rear grain stop ring of the grain is limited by the threaded end face of the nozzle. The wire of the ignition device is led out to the tail of the booster through the inner hole of the grain, the throat of the nozzle, and the inner hole of the plug. After the external thread at the tail of the nozzle is smeared with thread sealant, the plug is screwed onto the outlet of the nozzle. After the wire of the ignition device is led out of the plug, the inner hole of the plug is filled with glue. The push rod is inserted into the head of the front top cover, and the two are in clearance fit.

[0026] Next, in combination with the embodiments of the present utility model and the drawings, the technical solutions in the embodiments of the present utility model will be clearly and completely described. Obviously, the described embodiments are only a part of the embodiments of the present utility model, rather than all the obtained embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art belong to the scope of protection of the present utility model.

[0027] As Figure 1 shown, a solid rocket booster with an adiabatic coating includes a push rod 1, a front top cover 2, an ignition device 3, a grain 4, a combustion chamber shell 5, a grain stop ring 6, a plug 7, a nozzle 8, and an adiabatic coating 9.

[0028] As Figure 2 (Ⅰ) shown, the adiabatic coating 9 is sprayed and cured on the inner wall of the combustion chamber shell 5.

[0029] As Figure 3 (Ⅱ) shown, the front top cover 2 is also used for limiting the grain stop ring 6.

[0030] As Figure 4 (Ⅲ) shows, the nozzle 8 is also used for limiting the medicine blocking ring 6.

[0031] As Figure 1 shown, the sealing ring 10 prevents high-temperature and high-pressure gas from leaking at the interfaces between the combustion chamber housing 5 and the front top cover 2 and the nozzle 8. The medicine blocking ring 6 prevents the propellant charge 4 from swaying inside the combustion chamber housing 5.

[0032] During specific implementation, the thermal insulation coating 9 needs to be pre-sprayed and cured on the inner wall of the combustion chamber housing 5. The thermal insulation coating 9 adopts GT401 coating, and the coating requirements are implemented in accordance with WJ 2612-2003; the coating thickness is 0.4 mm to 0.5 mm; the coating adhesion standard is implemented in accordance with GB1720-1979 and is not lower than Grade 2; the threaded positions at the front and rear ends of the combustion chamber housing need to be protected, and no foreign matters such as coating residues are allowed to remain; the appearance of the coating paint film is flat on the surface, and no pinholes, cracks and bubbles are allowed.

[0033] The materials of the push rod 1, the front top cover 2, the combustion chamber housing 5, and the nozzle 8 are all selected as steel. After the external thread of the ignition device 3 is coated with thread sealant, it is screwed into the threaded hole at the center of the inner wall of the front top cover 2; the front top cover 2 and the combustion chamber housing 5 are connected by threads. After a sealing ring 10 is sleeved on the root of the external thread where the front top cover 2 and the combustion chamber housing 5 are butted, the front top cover 2 is screwed into the front opening of the combustion chamber housing 5; the front and rear end faces of the propellant charge 4 are subjected to limited combustion treatment, and only the inner hole and the outer cylindrical surface are reserved as the burning surface. Two medicine blocking rings 6 are respectively installed on the front and rear end faces of the propellant charge 4, and the medicine blocking ring 6 and the propellant charge 4 are in interference fit; the propellant charge 4 installed with the medicine blocking ring 6 is loaded from the rear opening of the combustion chamber housing 5, and the front medicine blocking ring 6 of the propellant charge 4 is limited by the threaded end face of the front top cover 2; the nozzle 8 and the combustion chamber housing 5 are connected by threads. After a sealing ring 10 is sleeved on the root of the external thread where the nozzle 8 and the combustion chamber housing 5 are butted, the nozzle 8 is screwed into the rear opening of the combustion chamber housing 5, and the rear medicine blocking ring 6 of the propellant charge 4 is limited by the threaded end face of the nozzle 8; the wire of the ignition device 3 is led out to the tail of the booster through the inner hole of the propellant charge 4, the throat of the nozzle 8, and the inner hole of the plug 7; after the external thread at the tail of the nozzle 8 is smeared with thread sealant, the plug 7 is screwed on the outlet of the nozzle 8; after the wire of the ignition device 3 is led out of the plug 7, the inner hole of the plug 7 is filled with glue; the push rod 1 is inserted into the head of the front top cover 2, and the two are in clearance fit.

[0034] When the booster works, the ignition device 3 is triggered by an external power supply. The ignition device 3 ignites the propellant charge 4, the plug 7 opens, and a large amount of gas is generated by the combustion of the ignition device 3 and the propellant charge 4 and is discharged from the nozzle 8 to generate thrust. During operation, the push rod 1 is connected to the unmanned aerial vehicle and the target drone, and the booster transmits the thrust to the unmanned aerial vehicle and the target drone through the push rod 1.

[0035] Obviously, those skilled in the art can make various changes and modifications to the embodiments of the present utility model without departing from the spirit and scope of the embodiments of the present utility model. Thus, if these modifications and variations of the embodiments of the present utility model fall within the scope of the claims of the present utility model and their equivalent technologies, the present utility model also intends to include these changes and modifications.

[0036] The solid rocket booster has an operating time of 2 s ± 0.2 s and an average thrust of 7000 N. For the test, ground hot-fire tests were carried out at high temperature (+40 °C) using the combustion chamber shell without an adiabatic coating and the combustion chamber shell with GT401 adiabatic coating respectively.

[0037] During the hot-fire test, the combustion chamber shell of the booster without an adiabatic coating burst when it worked for 1.8 s. Through analysis, it was located that due to the increase in the booster charge, the heat flux density flowing through the tail end of the combustion chamber shell increased, and the temperature of the combustion chamber shell rose under non-adiabatic conditions, resulting in a decrease in the strength of the metal shell and its inability to withstand the internal pressure during operation, leading to the bursting failure of the combustion chamber shell.

[0038] The booster with GT401 adiabatic coating passed the hot-fire test assessment throughout the process, and all indicators met the requirements. After the test, the structure of the booster was intact. The thrust-time curve of the hot-fire test is shown in Figure 5 the figure.

[0039] This technology has been applied to the solid rocket engine project. Aiming at the problem of the failure of the combustion chamber shell of the solid rocket booster, the technical approach of spraying adiabatic coating is adopted, which has a short production cycle, low production cost, mature technology, and can effectively improve the product reliability, and is of great significance for occupying the market of the take-off power devices of unmanned aerial vehicles and target drones.

Claims

1. A solid rocket booster with a thermal insulation coating, characterized in that: include: A push rod (1), the push rod is inserted into the head of the front top cover, and the two are clearance-fitted; A front top cover (2), the front top cover being connected to the combustion chamber housing via threads; An ignition device (3), the ignition device being connected to the front top cover via threads, the external threads of the ignition device being coated with thread glue and then screwed into the threaded hole at the center of the inner wall of the front top cover; Drug retaining rings (6), which are respectively arranged on the front and rear end surfaces of the drug column, and the drug retaining rings and the drug column are interference fit; A medicine column (4), wherein the medicine stop ring at the front end of the medicine column is limited by the threaded end surface of the front top cover, and the medicine stop ring at the rear end of the medicine column is limited by the threaded end surface of the nozzle; A combustion chamber shell (5), wherein the inner wall of the combustion chamber shell is coated with a heat insulating coating (9), and the front and rear end thread positions of the combustion chamber shell need to be protected, and no coating residue or foreign matter is allowed to remain; A nozzle (8), the nozzle being connected to the combustion chamber housing via threads; A plugging cover (7), the plugging cover being placed at the nozzle outlet; The heat insulating coating (9) is sprayed and cured on the inner wall of the combustion chamber shell. When spraying the heat insulating coating, the internal threads of the front and rear openings of the combustion chamber shell should be avoided.

2. The solid rocket booster with thermal insulation coating according to claim 1, characterized in that: A sealing ring is arranged at the connection position between the front top cover and the combustion chamber housing.

3. The solid rocket booster with thermal insulation coating according to claim 1, characterized in that: A sealing ring is arranged at the connection position between the nozzle and the combustion chamber shell.

4. The solid rocket booster with thermal insulation coating according to claim 1, characterized in that: The medicine retaining rings are respectively arranged on the front and rear end surfaces of the medicine column, and the medicine retaining rings are provided with buffer pads.

5. The solid rocket booster with thermal insulation coating according to claim 1, characterized in that: The front and rear end surfaces of the propellant are subjected to combustion-limiting treatment, leaving only the inner hole and the outer cylindrical surface as the combustion surfaces.

6. The solid rocket booster with thermal insulation coating according to claim 1, characterized in that: The coating film of the thermal insulation coating (9) has a smooth surface appearance and is not allowed to have pinholes, cracks or bubbles.

7. The solid rocket booster with thermal insulation coating according to claim 1, characterized in that: After the wire of the ignition device is led out of the plugging cover, the inner hole of the plugging cover is filled with glue.

8. The solid rocket booster with thermal insulation coating according to claim 7, characterized in that: The wire of the ignition device is led out to the tail of the booster through the inner hole of the charge, the throat of the nozzle, and the inner hole of the plugging cover.

9. The solid rocket booster with thermal insulation coating according to claim 1, characterized in that: After applying thread glue to the external thread at the tail of the nozzle, the plugging cap is screwed onto the nozzle outlet.

10. The solid rocket booster with thermal insulation coating according to claim 6, characterized in that: The thermal insulation coating (9) is GT401 coating with a coating thickness of 0.4 mm to 0.5 mm.

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