Composite blanking cap for separating engine jet pipe

By using a composite plug structure and adhesive bonding between the front rubber layer and the rear plug layer, the problems of air leakage in the nozzle plug and unreliable opening of the fairing are solved. This achieves reliable sealing and fairing opening over a wide temperature range, reduces costs, and improves processability.

CN120968952APending Publication Date: 2025-11-18SHANGHAI XINLI POWER EQUIP RES INST
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Patent Information

Application Number
CN202511210663.0
Authority / Receiving Office
CN · China
Patent Type
Applications(China)
Current Assignee / Owner
Filing Date
2025-08-27
Publication Date
2025-11-18

AI Technical Summary

Technical Problem

Existing nozzle plugs are prone to air leakage at the bonding interface and the fairing cannot be reliably opened, affecting the functional performance of the separation engine.

Method used

The fairing employs a composite cap structure, comprising a front rubber layer and a rear cap layer, which are bonded together with adhesive. The front rubber layer is reliably bonded to the conical surface of the expansion section, while the rear cap layer provides support to ensure the fairing can be reliably opened.

Benefits of technology

It achieves reliable sealing without leakage over a wide temperature range, ensures reliable opening of the fairing, improves bonding reliability and processability, and reduces costs.

✦ Generated by Eureka AI based on patent content.

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Abstract

The invention provides a composite blanking cap for separating an engine jet pipe. The composite blanking cap comprises a front rubber layer, a rear blanking cap layer and an adhesive, the outer convex surface of the rear blanking cap layer is bonded with the inner concave surface of the front rubber layer by adopting an adhesive; the front rubber layer provides a bonding surface for the composite blanking cap, and the outer convex surface of the front rubber layer and the conical inclined surface of the expansion section are bonded and cured by adopting an adhesive; the rear blanking cap layer provides support for the composite blanking cap, it is ensured that the damage form of the composite blanking cap is that the composite blanking cap flies out integrally, and power is provided for opening work of the separation engine fairing. The mode that the front rubber layer and the rear blanking cap layer are combined is adopted, the sealing performance is good, and safety and reliability are high; the composite blanking cap is simple in structure, low in cost, convenient to produce and operate, good in universality, good in inheritance and good in manufacturability.
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Description

Technical Field

[0001] This invention belongs to the field of solid rocket engine technology, specifically relating to a composite plug for a separate engine nozzle. Background Technology

[0002] Patent CN1089194231A indicates that the nozzle plug, as a key component of the engine, is mainly used for engine sealing and moisture prevention, and for shortening the ignition delay time to ensure reliable ignition during operation. In solid rocket motors used for interstage separation, the nozzle is usually angled, and the plug must also provide sufficient power to ensure that the separation engine cowling on the rocket body opens and that the engine nozzle is unobstructed. Due to the short operating time of the separation engine and the minimal impact of erosion, the nozzle expansion section is usually made of metal to save costs and improve manufacturability.

[0003] Existing nozzle plugs are mainly classified into two categories: metal plugs and non-metal plugs. Existing metal plugs exhibit leakage at the bonding interface and after long-term storage, severely impacting the performance of the separation engine. Non-metal plugs, such as rubber plugs, cannot reliably open the separation engine cowling; therefore, existing plug structures cannot be used directly. To address the shortcomings of existing technologies, there is an urgent need for a composite nozzle plug that can open the cowling while ensuring reliable bonding. Summary of the Invention

[0004] The purpose of this invention is to provide a composite plug for separating engine nozzles, which solves the problem that existing plugs cannot simultaneously guarantee bonding reliability and open the fairing.

[0005] To achieve the above objectives, the present invention adopts the following technical solution:

[0006] A composite plug for separating engine nozzles includes a front rubber layer, a rear plug layer, and an adhesive; the outer convex surface of the rear plug layer and the inner concave surface of the front rubber layer are bonded together with the adhesive.

[0007] The front rubber layer provides an adhesive surface for the composite plug, and its convex surface is bonded and cured with adhesive to the tapered inclined surface of the expansion section.

[0008] The rear cap layer provides support for the composite cap, ensuring that the composite cap is destroyed as a whole and providing power for the separation of the engine cowling.

[0009] The composite plug can withstand pressure of less than or equal to 0.1 MPa in both directions under storage conditions in the temperature range of -55 to 70℃.

[0010] The composite plug has an opening and damage area, and the damage mode is that the entire composite plug flies out.

[0011] The area to be opened and damaged is the bonding surface between the composite plug and the expansion section.

[0012] The length of the tapered bonding surface between the front rubber layer and the expansion section is determined by the opening pressure.

[0013] The concave surface of the front rubber layer matches the convex surface of the rear cap layer to form an adhesive surface; the area of ​​the adhesive surface is determined by the front rubber layer.

[0014] The conical surface of the expansion section and the convex surface of the rear cap layer are sanded before bonding to improve bonding reliability.

[0015] The front rubber layer and the rear plug layer are bonded and cured in a mold using an adhesive.

[0016] The expansion section is made of alloy steel, and its inner surface is a conical slope of 15° to 18°.

[0017] The front rubber layer is made of nitrile rubber material and is formed by molding, with a thickness of 1mm;

[0018] The rear plug layer is made of metal material through machining or spinning, and has a thickness of 0.5 to 2 mm;

[0019] The adhesive used is 730 glue.

[0020] The expansion section is made of 30CrMnSiA alloy steel.

[0021] The rear plug layer is made of aluminum alloy.

[0022] Compared with the prior art, the beneficial effects achieved by this invention are as follows:

[0023] 1. This invention provides a composite plug made of non-metallic and metallic materials for use in separating engine nozzles by combining a front rubber layer and a rear plug layer. The composite plug achieves reliable sealing by reliably bonding the convex surface of the rubber to the metal surface of the expansion section, resulting in good sealing performance and high safety and reliability.

[0024] 2. The composite plug structure used in this invention is simple, low in cost, easy to produce and operate, has good versatility and inheritance, and has good processability.

[0025] 3. The test results show that the nozzle after the composite plug is bonded does not leak air in a wide temperature range, has good environmental adaptability, and can reliably open the engine cowling, which can meet the usage requirements. Attached Figure Description

[0026] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0027] Figure 1 This invention provides a schematic diagram of the composition of a composite plug structure for a rocket separation engine nozzle;

[0028] Figure 2 This is a schematic diagram illustrating the assembly effect of a composite plug for a rocket separation engine nozzle, provided by the present invention.

[0029] Reference numerals: 1. Expansion section; 2. Composite plug; 3. Adhesive; 21. Front rubber layer; 22. Rear plug layer.

[0030] Specific implementation methods

[0031] The present invention will be further described below with reference to the accompanying drawings and specific embodiments. It should be noted that the drawings are all in a very simplified form and use non-precise ratios, and are only used to facilitate and clarify the purpose of illustrating the embodiments of the present invention.

[0032] A composite plug for separating engine nozzles includes a front rubber layer 21, a rear plug layer 22, and an adhesive 3; the outer convex surface of the rear plug layer 22 is bonded to the inner concave surface of the front rubber layer 21 by the adhesive 3.

[0033] The front rubber layer 21 provides an adhesive surface for the composite plug 2, and its convex surface is bonded and cured with the tapered inclined surface of the expansion section 1 using adhesive 3.

[0034] The rear cover layer 22 provides support for the composite cover 2, ensuring that the composite cover 2 is destroyed as a whole and provides power for the separation of the engine cowling.

[0035] The composite plug 2 has a forward and reverse pressure resistance of less than or equal to 0.1 MPa under storage conditions in the temperature range of -55 to 70℃.

[0036] The composite plug 2 has an opening and damage area, and the damage mode is that the composite plug 2 flies out as a whole.

[0037] The area to be opened and damaged is the bonding surface between the composite plug 2 and the expansion section 1.

[0038] The length of the tapered bonding surface between the front rubber layer 21 and the expansion section 1 is determined by the opening pressure.

[0039] The concave surface of the front rubber layer 21 matches the convex surface of the rear capping layer 22 to form an adhesive surface; the area of ​​the adhesive surface is determined by the front rubber layer 21.

[0040] Before bonding, the conical surface of the expansion section 1 and the convex surface of the rear cover layer 22 are both sanded to improve bonding reliability.

[0041] The front rubber layer 21 and the rear plug layer 22 are bonded and cured in a mold using adhesive 3;

[0042] The expansion section 1 is made of alloy steel, and its inner surface is a conical slope of 15° to 18°.

[0043] The front rubber layer 21 is made of nitrile rubber material and is formed by molding, with a thickness of 1mm;

[0044] The rear plug layer 22 is made of metal material through machining or spinning, and has a thickness of 0.5 to 2 mm;

[0045] The adhesive 3 is 730 glue.

[0046] The expansion section 1 is made of 30CrMnSiA alloy steel.

[0047] The rear cover layer 22 is made of aluminum alloy.

[0048] This embodiment proposes a composite plug for separating engine nozzles, such as... Figure 1 and Figure 2 As shown, the front rubber layer 21 is made using a mold, and the rear plug layer 22 is made by machining or spinning. After grinding the convex surface of the rear plug layer 22, it is bonded to the concave surface of the front rubber layer 21 with adhesive 3 and cured to form a composite plug 2 for later use. The conical inclined portion of the expansion section 1 is ground and bonded to the prepared composite plug 2 with adhesive 3 and cured.

[0049] Tests have shown that this composite plug does not leak air in a wide temperature range of -55 to 70°C, and the fairing can be reliably opened during engine separation tests. Therefore, this invention is suitable for the storage sealing and operating conditions of engines in a wide temperature range.

[0050] While the present invention has been disclosed above with reference to preferred embodiments, it is not intended to limit the invention. Any person skilled in the art can make possible variations and modifications to the technical solutions of the present invention using the disclosed methods and techniques without departing from the spirit and scope of the invention. Therefore, any simple modifications, equivalent changes, and alterations made to the above embodiments based on the technical essence of the present invention, without departing from the scope of the invention, are all within the protection scope of the present invention. Content not described in detail in this specification is common knowledge to those skilled in the art.

Claims

1. A composite plug for separating engine nozzles, characterized in that: The composite plug (2) includes a front rubber layer (21), a rear plug layer (22), and an adhesive (3); the outer convex surface of the rear plug layer (22) and the inner concave surface of the front rubber layer (21) are bonded together with the adhesive (3); The front rubber layer (21) provides an adhesive surface for the composite plug (2), and its convex surface is bonded and cured with the tapered slope of the expansion section (1) using adhesive (3); The rear cap layer (22) provides support for the composite cap (2), ensuring that the composite cap (2) is destroyed as a whole and provides power for the separation of the engine cowling to open.

2. The composite plug for separating engine nozzles according to claim 1, characterized in that: The composite plug (2) has a forward and reverse pressure of less than or equal to 0.1 MPa under storage conditions in the temperature range of -55 to 70℃.

3. The composite plug for separating engine nozzles according to claim 1, characterized in that: The composite plug (2) has an opening and damage area, and the damage mode is that the composite plug (2) flies out as a whole; The opening and damage area is the bonding surface between the composite plug (2) and the expansion section (1).

4. A composite plug for separating engine nozzles according to claim 1, characterized in that: The length of the tapered bonding surface between the front rubber layer (21) and the expansion section (1) is determined by the opening pressure.

5. A composite plug for separating engine nozzles according to claim 1, characterized in that: The concave surface of the front rubber layer (21) matches the convex surface of the rear capping layer (22) to form an adhesive surface; the area of ​​the adhesive surface is determined by the front rubber layer (21).

6. A composite plug for separating engine nozzles according to claim 1, characterized in that: The conical surface of the expansion section (1) and the convex surface of the rear capping layer (22) are both polished before bonding to improve bonding reliability.

7. A composite plug for separating engine nozzles according to claim 1, characterized in that: The front rubber layer (21) is made of nitrile rubber material and formed by molding.

8. A composite plug for separating engine nozzles according to claim 1, characterized in that: The rear cover layer (22) is made of aluminum alloy.

Citation Information

Patent Citations

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  • High-temperature-resistant blanking cap of solid rocket engine jet pipe

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  • Compound spindle nose blanking cover

    CN204664403U