CN110792528A - A kind of multi-ring groove medicine type structure forming combined core mold and process - Google Patents

Abstract

The invention provides a combined core mold and a process for forming a multi-ring groove medicine type structure. The combined core mold includes a main core mold, an umbrella disc, a sleeve, a snap ring and an actuating ring, and the main core mold is a columnar structure; The snap ring is a non-closed annular structure with a boss on the outside; the sleeve is installed outside the main core mold to limit the position of the snap ring in the axial direction of the main core mold; a temperature-sensitive actuating ring is used to surround it. Outside the snap ring, the actuating ring does not deform when the temperature is lower than the threshold value. The snap ring boss cooperates with the inner wall of the umbrella disc to limit the axial movement of the umbrella disc along the main core mold; when the temperature is higher than the threshold value, the actuation ring shrinks and shrinks. The boss of the snap ring is driven to separate from the umbrella plate, and the main core mold can move axially relative to the umbrella plate. The present invention does not need to perform machining operations such as turning, can form multiple pre-embedded ablative devices at one time, can be reused for many times, does not need disassembly and assembly, saves time and improves efficiency.

Description

A kind of multi-ring groove medicine type structure forming combined core mold and process

technical field

The invention relates to a solid rocket motor charge forming process.

Background technique

The working environment of the solid rocket motor is relatively harsh, the temperature adaptability of the engine is relatively wide, and the performance requirements are relatively high, which requires a high-loading charge structure design. The stress relief structure has become the key technology of the engine.

The application of the radial annular groove charge structure in foreign countries is earlier, and the corresponding technology is relatively mature. The foreign engines using the stress relief groove charge type include the American TU-780 engine, AIM-120* engine and RAM missile engine. There are three main ways for the annular groove structure: (1) mechanical processing, using a retractable turning tool device, and using a turning method to turn the annular groove inside the propellant; The umbrella tray made of ablable material is embedded, and it is integrated with the propellant after solidification. When the propellant is burned, it will burn together; After solidification, the umbrella plate is disassembled and taken out, and the ring groove is formed.

Due to the limitation of technology level and propellant materials in China, the current domestic molding is mainly single-ring groove, which adopts the ablative umbrella disk structure. When it is solidified into one body, the forming of the single ring groove is realized by disassembling the casting core mold. The mandrel used in the molding process is a detachable mandrel, and one end of the detachable mandrel is threaded, through which the sleeve is fixed on the mandrel of the mandrel, and the ablative umbrella disc is fixed through the sleeve and the mandrel to ensure that the drug When the slurry is poured, the position of the ablable umbrella plate does not change. After the slurry is solidified, the sleeve is pulled out from one end, and the mandrel is pulled out from the other end, so as to realize the formation of a single ring groove.

Advantages of various forming processes at home and abroad: (1) Machining and forming, using the method of turning forming, the structure size, position and number of ring grooves of the forming surface can be adjusted arbitrarily; (2) Pre-embedded ablation device, forming a single ring groove is fast, The structure of the forming tool is simple; (3) the detachable device is pre-embedded, and the multi-ring groove structure can be formed. Disadvantages of each molding process: (1) Machining and molding, the structure of the molding tool is complex, and the failure rate is high, and during the propellant turning process, it is easy to cause the propellant to generate heat by friction and ignite the propellant; (2) Pre-embedded ablation device , the disadvantage is that only a single ring groove can be formed, and a multi-ring groove structure cannot be formed; (3) the ablation and disassembly device is embedded in advance, and the forming tooling structure is complex.

SUMMARY OF THE INVENTION

In order to overcome the deficiencies of the prior art, the present invention provides a molding technology for a high-filling radial multi-annular-groove charge structure, which can realize the molding of an engine structure with strong adaptability and high performance. The present invention relates to the application technology of solid rocket motor.

The technical scheme adopted by the present invention to solve the technical problem is as follows: a composite core mould for forming a multi-ring groove medicine type structure, comprising a main core mould, an umbrella disc, a sleeve, a snap ring and an actuating ring.

The main core mold is a columnar structure; the snap ring is a non-closed annular structure with a boss on the outside; the sleeve is installed outside the main core mold to limit the position of the snap ring in the axial direction of the main core mold ;A temperature-sensitive actuating ring is used to surround the snap ring, the actuating ring does not deform when the temperature is lower than the threshold value, and the snap ring boss cooperates with the inner wall of the umbrella plate to limit the axial movement of the umbrella plate along the main core mold; When it is higher than the threshold value, the actuating ring becomes smaller, which drives the boss of the snap ring to separate from the umbrella plate, and the main core mold can move axially relative to the umbrella plate.

The invention comprises a plurality of umbrella discs, a plurality of sleeves, a plurality of snap rings and a plurality of actuating rings, and the umbrella discs and the bushings on which the snap rings and the actuating rings are installed are alternately installed on the main core mold.

The present invention also includes a fixing nut, which is threadedly connected with one end of the main core mold, and defines the axial positions of the sleeve and the snap ring on the main core mold.

The structural form of the snap ring includes a split ring structure and a segmented structure; for the split ring structure, the snap ring is a non-integral structure and opens along the circumferential direction; for the segmented structure, the snap ring is cut into three sections or Four sections are assembled into a non-closed ring; the cross-sectional shape of the snap ring is U-shaped or L-shaped.

The section of the actuating ring is square, rectangular or circular.

The actuating ring adopts shape memory alloy, shape memory polymer or bimetal temperature-sensitive material with different linear expansion coefficients.

The present invention also provides a multi-ring groove medicine structure molding process using the above-mentioned combined core mold, which includes the following steps: socketing the snap ring and the actuating ring together, installing it outside the main core mold, and matching the snap ring with the umbrella tray ; Sleeve the umbrella disc and the sleeve alternately on the main core mold, and position the sleeve and the main core mold axially to obtain a multi-ring groove forming core mold; Put the multi-ring groove forming core mold into the solid rocket motor combustion chamber shell , the propellant is poured into the combustion chamber shell, heated to 60 ° C ~ 70 ° C, and then kept warm. When the moving ring shrinks and deforms, the retaining ring is driven to deform, so that the retaining ring comes out of the umbrella tray; after the propellant is solidified, pull out main mandrel.

Install the umbrella tray under the environment of 60 ℃ ~ 70 ℃, and after standing to room temperature, the actuating ring will return to its original state, and the snap ring will be sleeved in the umbrella tray, and the propellant will be cast.

The beneficial effects of the present invention are: in view of the serious lack of the forming technology of the radial annular groove charge structure, a forming technology of the radial multi-annular groove charge structure is invented, and the radial annular groove charge structure is formed. Under the conditions of implementation, the production efficiency has been improved.

Compared with the prior art, the present invention has the following significant advantages:

1) The embedded part is an ablation device, no machining operations such as turning are required, and there is no danger of igniting the propellant;

2) Multiple pre-embedded ablative devices can be formed at one time, and multiple umbrella discs can be formed;

3) After the combined core mold is installed once, it can be reused many times without disassembly and assembly, which saves time and improves efficiency.

The forming technology can also be extended to other solid rocket motors as a means of forming a high-load radial annular groove charge structure.

Description of drawings

Fig. 1 is a schematic diagram of the overall structure of the combined core mold for medicine molding of the present invention;

Fig. 2 is the partial enlarged schematic diagram of the combination core mold for forming the medicine form of the present invention;

3 is a schematic view of the split ring structure with a U-shaped cross section;

Figure 4 is a schematic diagram of a segmented ring structure with a U-shaped section;

5 is a schematic view of a split ring structure with an L-shaped cross section;

FIG. 6 is a schematic diagram of a segmented ring structure with an L-shaped cross section;

Figure 7 is a schematic view of the structure of a circular section actuating ring;

Figure 8 is a schematic structural diagram of a square cross-section actuating ring;

FIG. 9 is a schematic structural diagram of an actuating ring with a rectangular cross section.

Detailed ways

The present invention will be further described below with reference to the accompanying drawings and embodiments, and the present invention includes but is not limited to the following embodiments.

The invention realizes the high filling fraction of the charge and the strong adaptability and high performance of the engine, solves the forming process of the high-loading radial multi-annular groove charge structure and the technical problem of combining core molds, so that the charge structure can ensure the filling of the charge structure. On the premise of the score, the process is optimized, and the pre-embedded ablation device is used to combine the mandrel to realize the molding of the multi-ring groove pre-embedded ablation device, which reduces the repeated installation and disassembly of the tooling and improves the work efficiency.

As shown in FIG. 1 and FIG. 2 , the combined core mold for medicine molding of the present invention includes a main core mold 1 , an umbrella tray 2 , a sleeve 3 , a fixing nut 4 , a snap ring 5 and an actuating ring 6 . The snap ring 5 and the actuation ring 6 are sleeved together and installed in the snap groove on the inner side of the umbrella pan 2 . The umbrella tray 2 is sleeved on the main core mold 1, the sleeve 3 is sleeved on the main core mold 1 from the other side of the main core mold 1, and the sleeve and the main core mold 1 are securely fixed by the fixing nut 6.

The combined mandrel includes a main mandrel, a plurality of umbrella discs, a plurality of sleeves, a fixing nut, a plurality of snap rings and a plurality of actuating rings. The snap ring and the actuating ring are sleeved together. After the multiple snap rings and actuating rings are set, they are installed on the inner side of the umbrella plate, and the umbrella plate and the casing with the snap rings and actuating rings are installed alternately on the main mandrel, and finally locked with the fixing nut. When the ambient temperature rises to the deformation temperature of the actuating ring, the actuating ring shrinks and deforms, and the snap ring is pulled out from the umbrella plate. Realize the overall demoulding.

The structural form of the snap ring can be: (1) split ring structure, the snap ring is a non-integral structure, opening along the ring direction; (2) segmented structure, the snap ring is cut into three or four segments; (3) the cross section of the snap ring The structure can adopt a U-shaped structure; (4) the cross-sectional structure of the snap ring can adopt an L-shaped structure.

The structure form of the actuating ring can be adopted: (1) overall circular structure with a square cross section; (2) overall circular structure with a rectangular cross section; (3) overall circular structure with a circular cross section.

The actuating ring can use shape memory alloys, shape memory polymers or bimetal temperature-sensitive materials with different linear expansion coefficients.

The technical process of realizing the invention is as follows:

Install the multi-ring groove forming core mold, sleeve the snap ring and the actuating ring together, and install it on the corresponding ring groove position of the main core mold. The umbrella tray is sleeved on the main mandrel, the sleeve is sleeved on the main mandrel from the other side, and the sleeve and the main mandrel are securely fixed by a fixing nut.

The multi-ring groove forming mandrel is loaded into the solid rocket motor combustion chamber casing, the propellant is poured into the combustion chamber casing, and it is moved into the drying workshop.

Raise the temperature in the drying room to 60°C to 70°C, and keep it warm for a long time. When the temperature of the combination core mold for medicine molding rises to 60°C to 70°C, the actuating ring shrinks and deforms, which drives the retaining ring to deform. Release the snap ring from the slot of the umbrella pan. After the propellant is cured, the whole mandrel can be directly pulled out from the big end of the main mandrel.

When the extraction temperature of the multi-ring groove mandrel is 60℃～70℃, install the umbrella tray at the same position. After standing to room temperature, the actuating ring will return to its original state, and the snap ring will be sleeved in the umbrella tray and can be delivered Propellant casting.

In this embodiment, the snap ring 6 adopts a U-shaped split ring structure, the actuating ring 5 adopts a shape memory alloy material, and the structural form is a circular cross-sectional structure. The installed composite mandrel for forming the medicine type is installed in the solid rocket motor combustion chamber shell, and then poured into the 50 ℃ medicine slurry. After the slurry casting is completed, the two ends of the solid rocket motor combustion chamber shell are sealed and placed horizontally in a curing room with an ambient temperature of 70 °C. The temperature of the combination core mold for medicine molding gradually increases. When the temperature rises to 60°C to 70°C, the actuating ring shrinks and deforms, which drives the clasp 5 to deform, so that the clasp 5 is displaced from the groove of the umbrella tray 2 . out. After the propellant is cured, the whole mandrel can be directly pulled out from the big end of the main mandrel 1. After the combined mandrel is pulled out of the propellant, install the umbrella tray 2 at the same position, and after standing at room temperature, the actuating ring 6 returns to its original state, and the snap ring 5 is sleeved in the umbrella tray 2 and can be delivered Propellant casting.

Claims (8)

1. The utility model provides a polycyclic groove medicine type structure shaping combination mandrel, includes main mandrel, umbrella dish, sleeve pipe, snap ring and action ring, its characterized in that: the main core mold is of a columnar structure; the clamping ring is of a non-closed annular structure, and a boss is arranged on the outer side of the clamping ring; the sleeve is arranged outside the main core mould to limit the position of the snap ring in the axial direction of the main core mould; the temperature-sensitive actuating ring is adopted to surround the outside of the clamping ring, the actuating ring does not deform when the temperature is lower than a threshold value, and the lug boss of the clamping ring is matched with the inner wall of the umbrella disc to limit the axial movement of the umbrella disc along the main core mold; when the temperature is higher than the threshold value, the actuation ring is reduced to drive the clamp ring boss to separate from the umbrella disk, and the main core die can axially move relative to the umbrella disk.

2. The multi-ring groove medicine type structure forming combined core mold as claimed in claim 1, characterized in that: the umbrella comprises a plurality of umbrella disks, a plurality of sleeves, a plurality of clamping rings and a plurality of actuating rings, wherein the umbrella disks and the sleeves which are provided with the clamping rings and the actuating rings are alternately arranged on a main core mold.

3. The multi-ring groove medicine type structure forming combined core mold as claimed in claim 1, characterized in that: the fixing nut is in threaded connection with one end of the main core die and limits the axial position of the sleeve and the clamping ring on the main core die.

4. The multi-ring groove medicine type structure forming combined core mold as claimed in claim 1, characterized in that: the structural form of the snap ring comprises an open ring structure and a segmented structure; in the split ring structure, the snap ring is of a non-integral structure and is opened along the circumferential direction; in the segmented structure, the clamping ring is cut into three or four segments to form a non-closed ring; the cross section of the snap ring is U-shaped or L-shaped.

5. The multi-ring groove medicine type structure forming combined core mold as claimed in claim 1, characterized in that: the section of the actuating ring is square, rectangular or circular.

6. The multi-ring groove medicine type structure forming combined core mold as claimed in claim 1, characterized in that: the actuating ring is made of shape memory alloy, shape memory polymer or bimetallic strip temperature sensitive materials with different linear expansion coefficients.

7. A multi-ring groove medicine type structure forming process utilizing the combined core mold is characterized by comprising the following steps: the clamping ring and the actuating ring are sleeved together and are arranged outside the main core mold, and the clamping ring is matched with the umbrella disc; alternately sleeving the umbrella disc and the sleeve on the main core mold, and axially positioning the sleeve and the main core mold to obtain a multi-ring-groove forming core mold; filling the multi-ring groove forming core mold into a combustion chamber shell of a solid rocket engine, pouring a propellant into the combustion chamber shell, heating to 60-70 ℃, preserving heat, and taking the propellant as a moving ring to shrink and deform to drive a snap ring to deform so that the snap ring is separated from an umbrella disc; and after the propellant is solidified, drawing out the main core mold.

8. The multi-ring groove drug-type structure molding process of claim 7, characterized in that: the umbrella disc is installed in the environment of 60-70 ℃, after standing to normal temperature, the actuating ring is restored to the original state, the clamping ring is sleeved in the umbrella disc, and downward propellant casting is carried out.

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