CN110355333B - Metal core mold structure for forming solid rocket engine shell - Google Patents
Metal core mold structure for forming solid rocket engine shell Download PDFInfo
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- CN110355333B CN110355333B CN201910771307.4A CN201910771307A CN110355333B CN 110355333 B CN110355333 B CN 110355333B CN 201910771307 A CN201910771307 A CN 201910771307A CN 110355333 B CN110355333 B CN 110355333B
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B22—CASTING; POWDER METALLURGY
- B22C—FOUNDRY MOULDING
- B22C9/00—Moulds or cores; Moulding processes
- B22C9/10—Cores; Manufacture or installation of cores
- B22C9/101—Permanent cores
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B22—CASTING; POWDER METALLURGY
- B22C—FOUNDRY MOULDING
- B22C9/00—Moulds or cores; Moulding processes
- B22C9/10—Cores; Manufacture or installation of cores
- B22C9/103—Multipart cores
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B22—CASTING; POWDER METALLURGY
- B22C—FOUNDRY MOULDING
- B22C9/00—Moulds or cores; Moulding processes
- B22C9/22—Moulds for peculiarly-shaped castings
- B22C9/24—Moulds for peculiarly-shaped castings for hollow articles
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- Mechanical Engineering (AREA)
- Moulding By Coating Moulds (AREA)
- Molds, Cores, And Manufacturing Methods Thereof (AREA)
Abstract
The invention discloses a metal core mold structure for forming a solid rocket engine shell, which consists of a large-end hook disk, a small-end hook disk, a joint gland, a positioning ring, a small-end curved surface part, a core mold split mold and a core shaft. The core mold split mold is characterized in that the curved surface of the core mold split mold is divided into a plurality of mold halves along the circumferential direction, wherein one mold half is a small part and is used for disassembling and assembling the core mold split mold; the sheets at the two ends of the split mold are provided with trapezoidal bosses protruding inwards, and the inner annular surfaces of the bosses are matched with the inner annular grooves of the corresponding large-end hook plate and the small-end hook plate to ensure the dimensional precision of the outer molded surface of the core mold; reinforcing ribs are arranged on two sides of each split mold to ensure radial rigidity in the winding process; the two ends of the split mold are provided with vertical downward vertical surfaces, so that the small end joint can be conveniently matched with the small end curved surface part; the inside locating ring that inlays of big end hook dish, little end hook dish annular internal surface and dabber closely cooperate. The core mold structure has the characteristics of convenience in disassembly and assembly, high positioning precision and long service life.
Description
Technical Field
The invention relates to a manufacturing technology of a solid rocket engine shell, in particular to a reusable metal core mould for a fiber winding shell of a solid rocket engine.
Background
The shell structure of the solid rocket engine is the most important part forming the passive mass of the engine, and has great influence on the thrust-weight ratio of the engine. The carbon fiber composite material has excellent performances of high specific strength, large specific modulus, corrosion resistance and the like, so that the carbon fiber composite material is widely applied to the field of solid rocket engines, and the performance of the solid rocket engines is obviously improved. The forming of the core mold is an important link as a basis and necessary step of the winding process design. The quality and precision of the core mold directly affect the subsequent winding, curing, demolding and machining processes.
Since the last 60 th century, the core mold technology has gone through three stages of an all-gypsum core mold and a sand core mold, an assembled gypsum core mold and a sand core mold, and a metal skeleton assembled gypsum core mold and a sand core mold. Because the gypsum core mould is easy to crack, poor in precision and the like, people develop a metal core mould and a metal framework external application gypsum core mould, then the core mould is still easy to crack along with the increase of the size of a composite material shell, the assembly and disassembly consume time and labor, and the precision is difficult to guarantee.
Disclosure of Invention
In order to avoid the defects of the prior art and overcome the problems that the assembly and disassembly of a metal core mould and a metal framework gypsum core mould are time-consuming and labor-consuming and the precision is difficult to ensure, the invention provides a metal core mould structure for the forming of a solid rocket engine shell; the mode of embedding a high-precision complete ring in a related structural member ensures that the core mold has higher radial dimension precision after being assembled so as to meet the actual engineering production requirement.
The core mold split mold comprises a large end connector gland, a large end locking piece, a nut, a large end connector, a bolt, a key, a screw, a large end positioning ring, a large end hook disc, a small end hook disc, an axial screw, a small end connector gland, a small end nut, a flat key, a locking nut, a limiting sleeve, a small end connector, a small end positioning ring, a small end curved surface part, a core mold split mold and a core shaft, and is characterized in that the core mold split mold is divided into a plurality of mold segments along the circumferential direction, wherein one mold segment is a small part and is used for dismounting the core mold split mold; the sheets at the two ends of the split mold are provided with trapezoidal bosses protruding inwards, and the inner annular surfaces of the bosses are matched with the inner annular grooves of the corresponding large-end hook plate and the small-end hook plate to ensure the dimensional precision of the outer molded surface of the core mold; reinforcing ribs are arranged on two sides of each split mold to ensure radial rigidity in the winding process;
a big end positioning ring is embedded in the big end hook disk and used for ensuring the radial size of the big end hook disk; the large-end locking part is connected with the large-end hook plate through a bolt, and is used for locking the core mold split mold profile curved surface formed by the split molds and limiting the axial size and position of the core mold; the big end locking part is connected with the core shaft through a key and a screw and used for locking the whole core mold to ensure the axial size of the core mold; the large-end connector is positioned outside the core mold split mold, is sequentially matched and connected with the large-end connector gland and the large-end locking piece and is locked by the nut;
the annular inner surface of the small-end hook plate is tightly matched with the mandrel, the small-end positioning ring and the small-end curved surface part are connected into a whole through an axial screw, the inner ring surface of the small-end positioning ring is abutted against the outer surface of the small-end hook plate, and the small-end curved surface part is sequentially matched and connected with the small-end connector, the small-end connector pressing cover, the limiting sleeve and the small-end nut and is fastened through the locking nut.
The big end hook disc, the big end positioning ring, the small end hook disc, the small end positioning ring, the small end curved surface part and the mandrel are coaxially arranged.
Advantageous effects
The invention provides a metal core mold structure for forming a solid rocket engine shell, which consists of a large-end hook disk, a small-end hook disk, a connector gland, a connector, a positioning ring, a small-end curved surface part, a core mold split mold and a core shaft. The outer curved surface of the core mold split mold adopts a circumferential split form, the outer surface of the core mold is divided into a plurality of detachable mold halves, one of which is a small part and is used for dismounting the core mold split mold; the sheets at the two ends of the split mold are provided with trapezoidal bosses protruding inwards, and the inner annular surfaces of the bosses are matched with the inner annular grooves of the corresponding large-end hook plate and the small-end hook plate, so that the dimensional precision of the outer molded surface of the core mold is ensured; reinforcing ribs are arranged on two sides of each split mold to ensure radial rigidity in the winding process; the inside locating ring that inlays of big end hook dish, little end hook dish annular internal surface and dabber closely cooperate. The core mould structure has the characteristics of convenient disassembly and assembly, high positioning precision, long service life and low production cost.
In order to overcome the difficulty brought by the outward sinking of the shoulder part of the small-end metal joint to the disassembly of the metal core mould, a part of the small-end curved surface part is cut to be matched with the small-end joint, and the radial precision and the integrated structure of the part are ensured by the small-end positioning ring, so that the disassembly convenience is ensured, and the dimensional precision of the part is also ensured. And the method is suitable for manufacturing a high-precision reusable solid rocket engine shell, and overcomes the defects of high production cost and low forming precision of a gypsum framework core mould and a sand core mould.
Drawings
The following describes a metal core mold structure for forming a solid rocket motor case according to the present invention in further detail with reference to the accompanying drawings and embodiments.
FIGS. 1(a), (b), (c) and (d) are views showing the structure of a metal core for forming a solid rocket engine case.
Fig. 2 is a schematic structural view of a metal core mold for forming a solid rocket motor case according to the present invention.
Fig. 3(a), (b), (c), (d) are schematic views of split mold parts.
Fig. 4(a), (b), (c), and (d) are schematic views of a casting split mold member.
Fig. 5(a) and (b) are schematic views of the large-end hook plate member.
FIG. 6 is a schematic view of a small end curved part.
In the drawings
1. 11, split die 12, large end head gland 13, large end locking piece 14, nut 15, large end head 16, bolt 17, key 18, screw 19, large end positioning ring 20, large end hook plate 21, small end hook plate 22, axial screw 23, small end head gland 24, small end nut 25, flat key 26, locking nut 27, stop collar 28, small end head 29, small end positioning ring 30, small end curved surface part
Detailed Description
The embodiment is a metal core mold structure for forming a solid rocket engine shell.
Referring to fig. 1 to 6, the metal core mold structure for forming the solid rocket engine casing in the present embodiment is composed of a large end joint gland 12, a large end locking piece 13, a nut 14, a large end joint 15, a bolt 16, a key 17, a screw 18, a large end positioning ring 19, a large end hook plate 20, a small end hook plate 21, an axial screw 22, a small end joint gland 23, a small end nut 24, a flat key 25, a locking nut 26, a stop collar 27, a small end joint 28, a small end positioning ring 29, a small end curved surface part 30, a core mold split mold and a core shaft; the core mold split mold is characterized in that the core mold split mold is divided into a plurality of mold halves along the circumferential direction, wherein one mold half is a small part and used for disassembling and assembling the core mold split mold; the sheets at the two ends of the split mold are provided with trapezoidal bosses protruding inwards, and the inner annular surfaces of the bosses are matched with the inner annular grooves of the corresponding large-end hook plate 20 and the small-end hook plate 21 to ensure the size precision of the outer molded surface of the core mold. Reinforcing ribs are arranged on two sides of each split mold to ensure radial rigidity in the winding process; each split has vertical downward facing vertical surfaces at both ends to mate with the small end fitting 28 and the small end curved member.
In this embodiment, cut apart into 11 mould lamellas with mandrel split mould appearance curved surface along the hoop, wherein, split mould 3, split mould 4, split mould 5, split mould 6, split mould 7, split mould 8, split mould 9, split mould 10 are equal split core mould lamella, and split mould 1, split mould 2, split mould 11 are unequal split core mould lamella, and each split core mould both sides all design into containing vertical decurrent thin slice to in cooperation with its adjacent split mould. The split mold 1 is a small metal split mold and is convenient to disassemble. The sheets at the two ends of the split mold are provided with inward convex trapezoidal bosses which are the key for ensuring the dimensional accuracy of the metal core mold, so that the annular surface at the lower part of the bosses must ensure enough accuracy, and the accuracy is determined according to the dimensional requirement of the final core mold outer profile. And the two side edges of each split mold are provided with downward ribs, when each split mold is thick, the welding method can generate not large deformation, and the forming precision of the outer surface of the core mold is not greatly influenced. If each split mold is thin, the rib is welded on the split mold by adopting a welding method to generate large deformation, and the requirement on forming precision is difficult to ensure, so that the split mold is required to be processed by using a casting method; the ribs and the outer surfaces of the split molds are sequentially cast, molded and then finish-machined, one rib can be cast in the two split molds during casting, and the cutting and finish machining can meet the requirement of preset size precision after the casting is finished.
The big end hook disk 20 is embedded with a big end positioning ring 19, and the positioning ring is used for ensuring the radial size of the big end hook disk. The big end locking piece 13 is connected with the big end hook plate 20 through a bolt 16, and the big end locking piece 13 is used for locking the core mould split mould outline curved surface formed by the split moulds, fastening the core mould external profile and limiting the axial size and position of the core mould. The large end locking piece 13 is connected with the mandrel through a key 17 and a screw 18 to lock the whole mandrel to ensure the axial dimension. The key on the mandrel is used for transmitting torque in the fiber winding process; the large-end connector 15 is positioned on the outer side of the core mold split mold, is sequentially matched and connected with the large-end connector gland 12 and the large-end locking piece 13, and is locked through the nut 14.
The annular inner surface of the small end hook disk is tightly matched with the mandrel, the small end positioning ring 29 and the small end curved surface part 30 are connected into a whole through the axial screw 22, and the inner ring surface of the small end positioning ring is tightly close to the outer surface of the small end hook disk. The small end curved surface part 30 is matched and connected with the small end joint 28, the small end joint gland 23, the limiting sleeve 27 and the small end nut 24 in sequence and is fastened through the locking nut 26; the inner surface of the small-end hook plate is matched with the trapezoidal bulge of the core mould split mould, so that the precision requirement of the core mould profile curved surface can be ensured. The actual small end fitting 28 has a shoulder that is angled outwardly, which can make it difficult to remove the split mold. The small end curved surface portion is cut off to fit the joint by a portion which is secured in its radial accuracy and degree of integration by a small end positioning ring 29. The small end curved surface part 30 is evenly divided into four parts along the circumferential direction, the four parts of small end curved surface parts are connected with the axial screw 22 into a whole through the small end positioning ring 29, and the radial dimensional accuracy of the small end curved surface part is ensured by means of the matching of the inner annular surface of the small end curved surface part and the outer surface of the small end hook disc; the method can ensure the convenience of disassembly and assembly and can also ensure the precision of the outer curved surface.
The big end locking piece 13 is an integrated flange plate part and is connected with a big end hook plate 20 through bolts 16. During assembly, the bolt 16 and the big-end hook plate 20 are firstly screwed, a certain gap is reserved between the bolt 16 and the big-end hook plate 20, and after all core mold split molds are assembled, the bolt 16 is screwed again to lock the big-end locking piece 13 and the big-end hook plate 20. The key 17 and flat key 25 are used to provide a torsional moment when the mandrel is rotated. The large-end joint gland 12, the nut 14, the small-end joint gland 23, the small-end nut 24 and the locking nut 26 are used for locking the axial position of the whole core mold, and the core mold is ensured to be an integral rigid body which cannot translate in the winding process.
The installation sequence is that the big end positioning ring 19 and the big end hook disk 20 are connected into a whole, the big end locking piece 13 and the big end hook disk 20 are screwed primarily through the bolt 16, and a certain gap is reserved between the big end positioning ring and the big end hook disk 20. The small-end hook disc 21 is tightly attached to the mandrel, the core mold split molds 1-11 are hooked in the annular groove of the small-end hook disc 21, meanwhile, the bolt 16 is screwed down to lock the large-end locking piece 13 and the large-end hook disc 20, and at this time, the core mold is molded in a curved surface mode. The small end curved surface part 30 is integrally mounted with the small end positioning ring 29 by the axial screw 22, and the inner ring surface thereof abuts against the outer surface of the small end hook disk 21. Installing the small end connector 28 and the large end connector 15, installing the limiting sleeve 27, installing the large end connector gland 12 and the small end connector gland 23, and locking the whole core mold by using the round nut 14, the small end nut 24 and the locking nut 26, so that the installation of the core mold is completed. During installation, the big end hook disk 20, the big end positioning ring 19, the small end hook disk, the small end positioning ring 29 and the small end curved surface part 30 are coaxially installed with the mandrel.
And the disassembly sequence comprises the steps of sequentially disassembling the external round nut 14, the small end nut 24 and the locking nut 26 of the core mold, pulling out the large end connector gland 12 and the small end connector gland 23, disassembling the bolt 16, disassembling the large end locking piece 13 and pulling out the core mold. The large end joint gland 12 and the large end positioning ring 19 take out the small end hook disc 21 from the large port. And (3) sequentially taking out the split mold 1, the split mold 2 and the split mold 3, the split mold 4, the split mold 5, the split mold 6, the split mold 7, the split mold 8, the split mold 9, the split mold 10 and the split mold 11, disassembling the axial screw 22, taking out the small end positioning ring 29, disassembling the small end curved surface part 30 and completing the disassembly of the core mold split mold.
In this embodiment, all parts all adopt metal material to make, and it is convenient to install, but each part independent dismouting, change, and the maintenance cost is low, long service life, reliability height.
Claims (2)
1. A metal core mould structure for forming a solid rocket engine shell comprises a large-end connector gland, a large-end locking piece, a nut, a large-end connector, a bolt, a key, a screw, a large-end positioning ring, a large-end hook plate, a small-end hook plate, an axial screw, a small-end connector gland, a small-end nut, a flat key, a locking nut, a limiting sleeve, a small-end connector, a small-end positioning ring, a small-end curved surface part, a core mould split mould and a core shaft, and is characterized in that the core mould split mould is divided into a plurality of mould halves along the circumferential direction, wherein one mould half is a small part and is used for dismounting the core mould split mould; the sheets at the two ends of the core mold split mold are provided with trapezoidal bosses protruding inwards, and the inner annular surfaces of the bosses are matched with the inner annular grooves of the corresponding large-end hook plate and the small-end hook plate to ensure the dimensional precision of the outer molded surface of the core mold; reinforcing ribs are arranged on two sides of each core mold split mold to ensure radial rigidity in the winding process;
a big end positioning ring is embedded in the big end hook disc and used for ensuring the radial size of the big end hook disc; the large-end locking piece is connected with the large-end hook plate through a bolt, and is used for locking the outline curved surface of the core mold split mold consisting of mold halves and limiting the axial size and position of the core mold; the large-end locking piece is connected with the core shaft through a key and a screw and used for locking the whole core mold to ensure the axial size of the core mold; the large-end connector is positioned outside the core mold split mold, is sequentially matched and connected with the large-end connector gland and the large-end locking piece and is locked by the nut;
the annular inner surface of the small-end hook plate is tightly matched with the mandrel, the small-end positioning ring and the small-end curved surface part are connected into a whole through an axial screw, the inner ring surface of the small-end positioning ring is abutted against the outer surface of the small-end hook plate, and the small-end curved surface part is sequentially matched and connected with the small-end connector, the small-end connector pressing cover, the limiting sleeve and the small-end nut and is fastened through the locking nut.
2. The metal core mold structure for molding the solid rocket motor case as recited in claim 1, wherein said large end hook disk, said large end positioning ring, said small end hook disk, said small end positioning ring, said small end curved surface member and said core shaft are coaxially mounted.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201910771307.4A CN110355333B (en) | 2019-08-21 | 2019-08-21 | Metal core mold structure for forming solid rocket engine shell |
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201910771307.4A CN110355333B (en) | 2019-08-21 | 2019-08-21 | Metal core mold structure for forming solid rocket engine shell |
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| CN110355333A CN110355333A (en) | 2019-10-22 |
| CN110355333B true CN110355333B (en) | 2021-01-05 |
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| CN201910771307.4A Expired - Fee Related CN110355333B (en) | 2019-08-21 | 2019-08-21 | Metal core mold structure for forming solid rocket engine shell |
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| CN110722719A (en) * | 2019-11-14 | 2020-01-24 | 江苏君澄空间科技有限公司 | Reusable mould for producing large-size lining-free composite material storage box |
| CN110722810A (en) * | 2019-11-14 | 2020-01-24 | 湖北三江航天江北机械工程有限公司 | Winding shell net size forming method |
| CN111890705B (en) * | 2020-03-26 | 2022-11-04 | 中国运载火箭技术研究院 | Satellite support mould |
| CN111957901A (en) * | 2020-08-25 | 2020-11-20 | 湖北三江航天江北机械工程有限公司 | Large-diameter engine shell gypsum core mold forming method |
| CN113001451B (en) * | 2021-03-07 | 2022-07-05 | 西北工业大学 | Large-scale split type metal mandrel assembly fixture |
| CN113103480A (en) * | 2021-04-01 | 2021-07-13 | 西北工业大学 | Split type metal core die for winding large solid rocket engine shell |
| CN113650200B (en) * | 2021-07-01 | 2023-06-13 | 西北工业大学 | Cementing tool for manufacturing split type composite material core mold |
| CN113967724B (en) * | 2021-10-21 | 2024-01-09 | 江苏新扬新材料股份有限公司 | Small-opening engine shell core mold and using method thereof |
Family Cites Families (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN202129355U (en) * | 2011-06-09 | 2012-02-01 | 西北工业大学 | Spinning core die for members with transverse inner ribs |
| CN104354436B (en) * | 2014-11-07 | 2016-03-02 | 湖北三江航天江北机械工程有限公司 | The manufacture method of high-temperature fibre wound composite housing |
| CN204398344U (en) * | 2014-12-05 | 2015-06-17 | 上海复合材料科技有限公司 | A kind of composite core formwork for making elongate composite motor body |
| CN105150438B (en) * | 2015-08-19 | 2017-08-22 | 湖北三江航天江北机械工程有限公司 | The wound and solidified device of carbon fibre composite thin-walled skirt type part |
| CN108059403A (en) * | 2017-11-07 | 2018-05-22 | 湖北三江航天江北机械工程有限公司 | Big L/D ratio fiber winding motor case gypsum mandrel molding method |
| CN108590886A (en) * | 2018-05-23 | 2018-09-28 | 精功（绍兴）复合材料有限公司 | Wrapping formed mold of birdcage rocket engine cast and preparation method thereof |
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