Turbine outer ring preform forming mold and process

Abstract

The present invention discloses a turbine outer ring preform forming mold and process, and the present invention relates to the field of engine manufacturing technology. A turbine outer ring preform forming mold and process, comprising a base and an upper mold and a lower mold for pressing and forming the preform; the lower mold comprises a first positioning block, a second positioning block and a third positioning block; the first positioning block is arranged horizontally and comprises a first end and a second end respectively embedded in the base; the second positioning block is arranged above the first end; the third positioning block is arranged above the second end, the third positioning block is clamped in the base and detachably connected to the base, and the third positioning block is arranged opposite to the second positioning block; the upper mold is pressed with the corresponding positioning block. The present invention is not only conducive to the subsequent vapor deposition treatment of the preform, but also conducive to improving the forming accuracy of the preform. Through this flexible forming mold, a turbine outer ring preform with high dimensional accuracy requirements can be prepared.

Description

Technical Field

[0001] The present invention relates to the technical field of engine manufacturing, and in particular to a turbine outer ring preform forming die and process. Background Art

[0002] The description of the background technology in the present invention belongs to the related technology related to the present invention and is only used to illustrate and facilitate understanding of the invention content of the present invention. It should not be understood that the applicant explicitly believes or infers that the applicant believes that it is the prior art of the present invention on the filing date of the first application.

[0003] The turbine outer ring is a crucial component of an engine's turbine mechanism. Its primary function is to isolate the engine from high-temperature combustion gases and maintain the integrity of the casing structure. Its development and manufacturing capabilities significantly impact engine performance.

[0004] SiC f As a new type of strategic material integrating thermal structure and function, SiC composite material has the characteristics of low density, high temperature resistance, high specific strength, high specific modulus, oxidation resistance, ablation resistance, insensitivity to cracks, and no catastrophic damage. It is widely used in aviation, aerospace, nuclear power and photovoltaic fields.

[0005] The turbine outer ring is preformed from laminated silicon carbide cloth, produced via chemical vapor deposition. The development trend for turbine outer ring components is toward integral fiber molding with high fiber continuity, eliminating the need for in-line riveting or machining. Existing solid molding dies for complex SiC / SiC and C / SiC composite fiber fabrics utilize a molding process that manually controls the relative position of the inner and outer molds. This process presents challenges such as difficult surface control during the lamination process, difficulty in sewing, eccentric mold positioning, and fiber fabric breakage caused by contour processing. Therefore, it cannot be applied to the high-precision turbine outer ring molding process. Summary of the Invention

[0006] The purpose of the present invention is to provide a turbine outer ring preform forming mold and process to solve the problem that the existing solid forming mold has poor mold positioning during the lamination process and cannot produce turbine outer rings with high precision requirements.

[0007] The technical solution of the present invention to solve the above technical problems is as follows:

[0008] A turbine outer ring preform forming mold, which includes a base and an upper mold and a lower mold for press-molding preforms; the lower mold includes a first positioning block, a second positioning block and a third positioning block; the first positioning block is arranged horizontally, and includes a first end and a second end respectively connected to the base, the second positioning block is arranged above the first end at intervals, and the second positioning block is detachably connected to the first positioning block; the third positioning block is arranged above the second end at intervals, the third positioning block is detachably connected to the base, and the third positioning block is arranged opposite to the second positioning block; the upper mold is pressed with the corresponding first positioning block and third positioning block, and the first positioning block, the third positioning block and the upper mold are all provided with suture holes for sewing corresponding woven fabrics.

[0009] The beneficial effects of adopting the above technical solution are as follows: the base is placed on a horizontal workbench, the first end and the second end are respectively installed on the base, the first layer of braided fabric is first laid on the first positioning block and simply sewed to the first positioning block, the second layer of braided fabric is laid on the first layer of braided fabric, and the fitting parts of the first layer of braided fabric and the second layer of braided fabric are simply sewed to the first positioning block; the second positioning block is placed on the second layer of braided fabric and connected to the first positioning block, and the second positioning block positions and presses the fitting parts of the first layer of braided fabric and the second layer of braided fabric; the third layer of braided fabric is laid on the third positioning block, and the third positioning block is then installed on the base, and finally the fourth layer of braided fabric is laid between the third layer of braided fabric and the second layer of braided fabric, and the fitting parts of the first layer of braided fabric, the second layer of braided fabric, the third layer of braided fabric and the fourth layer of braided fabric are simply sewed to the first positioning block. Tightly sew the third positioning block and the first positioning block as a whole; remove the second positioning block from the first positioning block, connect the corresponding upper mold with the first positioning block and the third positioning block, fold one end of the second layer of braided fabric 180° and lay it on the corresponding upper mold, and simply sew the fitting parts, lay the fifth layer of braided fabric on the first layer of braided fabric and the second layer of braided fabric, tightly sew the fitting parts of the first layer of braided fabric and the fifth layer of braided fabric with the first positioning block, and tightly sew the fitting parts of the second layer of braided fabric and the fifth layer of braided fabric with the corresponding upper mold. When the corresponding braided fabric is laid and sewn with the corresponding positioning block, a preform formed by the braid stack is obtained, remove the base, align the corresponding upper mold with the first positioning block and press it, so that the preform is compacted and subjected to vapor deposition treatment.

[0010] Considering that the turbine outer ring preform is small in size and has a complex structure, it needs to be stacked and laid layer by layer, and the corresponding woven fabrics are all strips of cloth with no fixed shape. Therefore, during the molding process of the preform, not only does the mold need to meet the shape requirements of the preform, but the mold also needs to be easy to adjust and position. This technical solution designs the mold into a structure that is used in conjunction with an upper mold and a lower mold based on the shape of the preform, and the structure of the lower mold is three detachable positioning blocks, so that the corresponding woven fabrics can be laid layer by layer, and the corresponding positioning blocks are provided with suture holes. Each time a layer of woven fabric is laid, the corresponding parts can be sutured, so that the woven fabrics are not easily separated or broken, and the woven fabrics and the positioning blocks are not easily separated or broken, reducing the degree of distortion during the stacking of the woven fabrics. This is not only beneficial for the subsequent vapor deposition treatment of the preform, but also beneficial for improving the molding accuracy of the preform. Turbine outer ring preforms with high dimensional accuracy requirements can be prepared through such a flexible molding mold.

[0011] Furthermore, the upper mold includes a first pressing block and a second pressing block connected to each other, the first pressing block is arranged above the first end, the second pressing block is located between the third positioning block and the first pressing block, and the end of the second pressing block close to the second end is detachably connected to the third positioning block, and the end of the second pressing block close to the first end is connected to the first pressing block.

[0012] Furthermore, the second pressing block includes a connecting plate and a clamping plate connected to each other, the connecting plate is located between the third positioning block and the first pressing block, the clamping plate is located between the first positioning block and the first pressing block, the clamping plate is arranged opposite to the third positioning block, and the clamping plate is provided with a suture hole.

[0013] The beneficial effects of adopting the above technical solution are as follows: when the first layer of braided fabric, the second layer of braided fabric, the third layer of braided fabric and the fourth layer of braided fabric are laid, due to the irregular shape of the preform, after laying, the connecting plate is used to press the braided fabric laid on the second end and the third positioning block, and the second pressing block is tightly sewn with the corresponding braided fabric, and then the first pressing block is connected to the second pressing block, and the first pressing block presses the first positioning block. The first pressing block and the second pressing block of this technical solution are used in combination, and the contact surfaces of the first pressing block and the second pressing block are in contact with the relative braids respectively, and force is applied to the first positioning block and the third positioning block respectively to press the woven preform. The upper mold of this technical solution is a detachable structure, and a contact surface adapted to different preform shapes is set, so that the upper mold can better contact the corresponding braid, thereby improving the pressing effect of the upper mold.

[0014] Furthermore, a connecting slot is provided on the top of the connecting plate, and the first pressing block is clamped in the connecting slot; the connecting plate, the third positioning block and the first positioning block are connected by a first pin shaft.

[0015] Furthermore, a first connecting block is provided on both sides of the first positioning block, and a second connecting block is provided on both sides of the second positioning block, and the first connecting block and the second connecting block are connected by a second pin shaft; a third connecting block is provided on both sides of the clamping plate, and the first connecting block and the third connecting block are connected by a third pin shaft; a third limiting block is provided between the first connecting block and the second connecting block, and between the first connecting block and the third connecting block.

[0016] The beneficial effects of adopting the above scheme are: considering that the clamping plate is installed after the second positioning block is removed, the second positioning block and the clamping plate of this technical solution are both detachable structures, which meet the molding shape requirements of the preform and greatly improve the flexibility of use. The second positioning block can also press the laid second layer of woven fabric and the first layer of woven fabric, which is conducive to laying subsequent woven fabrics, and the degree of pressing of the second positioning block and the clamping plate can be determined by the height of the third limit block to avoid the problem of excessive pressing.

[0017] Furthermore, the upper mold is pressed together with the lower mold through the reinforcement frame, the first positioning block, the third positioning block and the upper mold are connected in sequence, the reinforcement frame is arranged horizontally, the bottom inner wall of the reinforcement frame is connected to the first positioning block, the inner wall on one side of the reinforcement frame is respectively connected to the first end and the corresponding upper mold, and a fourth limit block is respectively arranged between the inner wall on the other side of the reinforcement frame and the second end and between the corresponding upper molds, and a fifth limit block is arranged between the top inner wall of the reinforcement frame and the corresponding upper mold.

[0018] Furthermore, the number of the reinforcement frames is 2, and the two reinforcement frames are respectively located on both sides of the upper mold and the lower mold, and the two reinforcement frames are arranged parallel to each other.

[0019] The beneficial effects of adopting the above technical solution are: after the upper mold and the lower mold are pressed together, the braided fabric is sewn to the upper mold and the lower mold respectively, the base is removed from the first positioning block, the upper mold and the lower mold are framed with a reinforcement frame, and the gap between the upper mold and the lower mold is limited and filled with the first limit block and the second limit block. The reinforcement frame can avoid the separation of the upper mold and the lower mold, increase the connection strength between the upper mold and the lower mold, thereby ensuring that the preform does not suffer serious displacement during the vapor deposition process.

[0020] A process for forming a turbine outer ring preform mold comprises the following steps:

[0021] S1: Place the base on a horizontal workbench, embed the first end and the second end in the base respectively, lay the first layer of braid and the second layer of braid on the first positioning block from bottom to top, lay the filling braid in the gaps formed by the corresponding braids, and simply sew the corresponding fitting parts of the braid to the first positioning block;

[0022] S2: placing a second positioning block on the second layer of braided fabric and connecting the second positioning block to the first positioning block;

[0023] S3: Laying a third layer of braided fabric on the third positioning block, connecting the third positioning block to the base, with the third layer of braided fabric positioned between the first and second layers of braided fabric. Laying filling braided fabric in the gaps formed by the corresponding braided fabrics, and simply sewing the corresponding fitting parts of the braided fabrics to the third positioning block and the first positioning block as a whole.

[0024] S4: Laying a fourth layer of braided fabric between the second and third layers of braided fabric, laying a filling braided fabric in the gaps formed by the corresponding braided fabrics, and tightly sewing the corresponding fitting parts of the braided fabrics to the third positioning block and the first positioning block;

[0025] S5: The second positioning block is removed from the first positioning block, and the corresponding upper mold is pressed together with the third positioning block. The second layer of braided fabric is folded at a certain angle and laid on the corresponding upper mold. The fifth layer of braided fabric is laid on top of the first and second layers of braided fabric. The gaps formed by the corresponding braided fabrics are filled with braided fabric. The corresponding fitting parts of the braided fabrics are tightly sewn to the corresponding upper mold and the first positioning block.

[0026] S6: Pressing the corresponding upper mold and the first positioning block to obtain a preform, removing the base, and using chemical vapor deposition to obtain a turbine outer ring blank.

[0027] Furthermore, the first braided fabric layer, the second braided fabric layer, the third braided fabric layer, the fourth braided fabric layer and the fifth braided fabric layer are made of silicon carbide cloth or carbon cloth.

[0028] The beneficial effects of adopting the above technical solution are: silicon carbide cloth or carbon cloth can not only meet the preparation of different shapes and sizes and preforms, but also has the advantages of low density, high temperature resistance, oxidation resistance, ablation resistance and no catastrophic damage, meeting the use requirements of the turbine outer ring.

[0029] Furthermore, the material of the sewing thread is 1K or 3K carbon fiber.

[0030] The present invention has the following beneficial effects:

[0031] (1) The present invention designs the mold into a structure in which an upper mold and a lower mold are used in conjunction with each other according to the shape of the preform, and the structure of the lower mold is three detachable positioning blocks, so that the corresponding braids can be laid layer by layer. Suture holes are provided on the corresponding positioning blocks. Each time a layer of braid is laid, the corresponding parts can be sewn, so that the braids are not easily separated or broken, and the braids and the positioning blocks are not easily broken, and the degree of distortion during the stacking of the braids is reduced. This is not only beneficial for the subsequent vapor deposition treatment of the preform, but also beneficial for improving the molding accuracy of the preform. By using such a flexible molding mold, a turbine outer ring preform with high dimensional accuracy requirements can be prepared.

[0032] (2) The first pressing block and the second pressing block of the present invention are used in conjunction with each other. The contact surfaces of the first pressing block and the second pressing block are respectively in contact with the opposite woven fabrics. Forces are applied to the first positioning block and the third positioning block respectively to press the preform formed by the woven fabric. The upper mold of the present invention is a detachable structure. Contact surfaces adapted to different preform shapes are provided, so that the upper mold can better contact the corresponding woven fabric, thereby improving the pressing effect of the upper mold.

[0033] (3) The second positioning block and the pressing plate of the present invention are both detachable structures, which meet the molding shape requirements of the preform and greatly improve the flexibility of use. The second positioning block can also press the laid second layer of woven fabric and the first layer of woven fabric, which is conducive to laying subsequent woven fabrics, and the degree of pressing of the second positioning block and the pressing plate can be determined by the height of the limit block to avoid the problem of excessive pressing. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] Figure 1 It is a structural schematic diagram of the turbine outer ring preform forming mold of the present invention.

[0035] Figure 2 This is a schematic structural diagram of the turbine outer ring preform of the present invention.

[0036] Figure 3 It is a structural schematic diagram of the base of the present invention.

[0037] Figure 4 This is a schematic structural diagram of the second positioning block of the present invention.

[0038] Figure 5 It is a structural schematic diagram of the upper mold of the present invention.

[0039] Figure 6 It is a structural schematic diagram of the second pressing block of the present invention.

[0040] Figure 7 It is a structural schematic diagram of the reinforcement frame of the present invention.

[0041] In the figure: 1-upper mold; 101-first pressing block; 102-second pressing block; 121-connecting plate; 122-pressing plate; 123-connecting slot; 2-lower mold; 201-first positioning block; 211-first end; 212-second end; 202-second positioning block; 203-third positioning block; 3-suture hole; 4-base; 5-reinforcement frame; 601-first layer of braid; 602-second layer of braid; 603-third layer of braid; 604-fourth layer of braid; 605-fifth layer of braid; 606-filling braid; 701-first connecting block; 702-second connecting block; 703-third connecting block; 801-first pin; 802-second pin; 803-third pin; 901-first limiting block; 902-second limiting block; 903-third limiting block. DETAILED DESCRIPTION

[0042] The principles and features of the present invention are described below with reference to the accompanying drawings. The examples given are only used to explain the present invention and are not used to limit the scope of the present invention.

[0043] Please refer to Figure 1 A turbine outer ring preform forming mold comprises a base 4, an upper mold 1 for pressing and forming the preform, and a lower mold 2 for pressing and forming the preform. The lower mold 2 is used to lay multiple layers of braided fabric to form the preform. The upper mold 1 and lower mold 2 are pressed together, and the preform is then subjected to a vapor deposition process. The multiple layers of braided fabric are laid one by one in the lower mold 2 to form the preform. The upper mold 1 and lower mold 2 are closed and pressed together to form the preform. The mold design with the upper mold 1 and lower mold 2 used in conjunction facilitates the laying of the braided fabric and is more flexible.

[0044] Please refer to Figure 1 and Figure 2In this embodiment, the turbine outer ring preform includes a first layer of braid 601, a second layer of braid 602, a third layer of braid 603, a fourth layer of braid 604, a fifth layer of braid 605, and a filling braid 606 for filling the gaps formed by the corresponding braids. The second layer of braid 602 is laid on the first layer of braid 601 and folded 180°, one end of the fifth layer of braid 605 is laid on the first layer of braid 601, and the other end of the fifth layer of braid 605 is laid on the folded part of the second layer of braid 602, so that a gap is formed between the first braid and the second layer of braid 602, and a gap is formed between the first braid, the fifth layer of braid 605, and the second layer of braid 602; the third layer of braid 603 has a U-shaped cross-section and is laid between the second layer of braid 602 and the first layer of braid 601, and the fourth layer of braid 604 is laid between the second layer of braid 602 and the third layer of braid 603, so that a gap is formed between the second layer of braid 602, the first layer of braid 601, and the third layer of braid 603, and a gap is formed between the second layer of braid 602, the third layer of braid 603, and the fourth layer of braid 604. The gaps are filled with corresponding braided fillers 606. It is worth noting that the braided fillers 606 are prefabricated, shaped to match the corresponding gaps, and have a layer of glue applied to their outer walls for adhesion to the corresponding gaps. In other embodiments, the preform may have other shapes and may have more or fewer than five layers of braid.

[0045] Please refer to Figure 1 and Figure 3 The base 4 is an inverted U-shape, and step slots are provided at both ends of the base 4. In this embodiment, one step slot is provided at one end of the top of the base 4, and two step slots are provided at the other end of the top of the base 4.

[0046] The lower mold 2 includes a first positioning block 201 for laying the first and second layers of braid 601, 602; a second positioning block 202 for pressing the first and second layers of braid 601, 602; and a third positioning block 203 for laying the third and fourth layers of braid 603, 604. The first positioning block 201 is arranged horizontally and includes a first end 211 and a second end 212, respectively embedded in a stepped slot on the base 4. The second positioning block 202 is positioned above the first end 211, and the third positioning block 203 is positioned above the second end 212. The second positioning block 202 is positioned above the first end 211 and opposite the third positioning block 203.

[0047] The first positioning block 201 and the third positioning block 203 are both provided with suture holes 3 for sewing corresponding woven fabrics. The suture holes 3 are arranged at intervals. Each positioning block can set the diameter of the suture holes 3 and the number of rows of the suture holes 3 according to suture requirements.

[0048] The process of laying the preform braided fabric is as follows: (1) the base 4 is placed on a horizontal workbench, the first positioning block 201 is installed on the base 4, and the first layer of braided fabric 601 is first laid on the first positioning block 201 and simply sewed to the first positioning block 201; (2) the second layer of braided fabric 602 is laid on the first layer of braided fabric 601, the fitting parts of the first layer of braided fabric 601 and the second layer of braided fabric 602 are simply sewed to the first positioning block 201, and the second positioning block 202 is installed on the first positioning block 201 to press the first layer of braided fabric 601 and the second layer of braided fabric 602; (3) the third layer of braided fabric 603 is laid on the third positioning block 203, and then the third positioning block 203 is installed on the base 4, and finally the fourth layer of braided fabric 604 is laid between the third layer of braided fabric 603 and the second layer of braided fabric 602, and the first layer of braided fabric 601 is laid on the third positioning block 203. , the fitting parts of the second layer of braid 602, the third layer of braid 603 and the fourth layer of braid 604 are tightly sewn with the third positioning block 203 and the first positioning block 201; (4) the second positioning block 202 is removed, and the corresponding upper mold 1 is installed. One end of the second layer of braid 602 is folded 180 degrees and laid on the upper mold 1, and then one end of the fifth layer of braid 605 is laid on the first layer of braid 601, and the other end of the fifth layer of braid 605 is laid on the second layer of braid 602, and the fitting parts of the first layer of braid 601 and the fifth layer of braid 605 are tightly sewn with the first positioning block 201, and the fitting parts of the second layer of braid 602 and the fifth layer of braid 605 are tightly sewn with the corresponding upper mold 1; (5) when the corresponding braid is laid and tightly sewn with the corresponding positioning block, a preform formed by the braid stack is obtained.

[0049] Please refer to Figure 1 、 Figure 5 and Figure 6The upper mold 1 includes a first pressing block 101 and a second pressing block 102 that are connected to each other. The first pressing block 101 is arranged above the first end 211, and the end of the second pressing block 102 close to the second end 212 is detachably connected to the third positioning block 203. The second pressing block 102 includes a connecting plate 121 and a pressing plate 122 that are connected to each other. The connecting plate 121 is located between the third positioning block 203 and the first pressing block 101, and the pressing plate 122 is located between the first positioning block 201 and the first pressing block 101. The pressing plate 122 is arranged opposite to the third positioning block 203, and the pressing plate 122 is provided with a suture hole 3. A connecting slot 123 is provided on the top of the connecting plate 121, and the first pressing block 101 is clamped in the connecting slot 123; the connecting plate 121, the third positioning block 203 and the first positioning block 201 are connected by a first pin 801. A third limiting block 903 is provided between the first connecting block 701 and the second connecting block 702, and between the first connecting block 701 and the third connecting block 703. After the first layer of braid 601, the second layer of braid 602, the third layer of braid 603 and the fourth layer of braid 604 are laid, due to the irregular shape of the preform, after the laying is completed, the connecting plate 121 is used to press the braid laid on the second end 212 and the third positioning block 203, and tightly sew the second pressing block 102 with the corresponding braid, and then connect the first pressing block 101 with the second pressing block 102, and the first pressing block 101 presses the first positioning block 201. The first pressing block 101 and the second pressing block 102 of the present invention are used in combination, and the contact surfaces of the first pressing block 101 and the second pressing block 102 are in contact with the relative braids respectively, and force is applied to the first positioning block 201 and the third positioning block 203 respectively to press the preform formed by the weaving. The upper mold 1 of the present invention is a detachable structure, and contact surfaces adapted to different preform shapes are provided, so that the upper mold 1 can better contact the corresponding braided fabric, thereby improving the pressing effect of the upper mold 1.

[0050] The second positioning block 202 must be installed first and needs to be disassembled before installing the second pressing block 102. Both the second positioning block 202 and the second pressing block 102 are connected to the first positioning block 201. First connecting blocks 701 are provided on both sides of the first positioning block 201, and second connecting blocks 702 are provided on both sides of the second positioning block 202. The first connecting blocks 701 and the second connecting blocks 702 are connected by a second pin 802. Third connecting blocks 703 are provided on both sides of the pressing plate 122, and the first connecting blocks 701 and the third connecting blocks 703 are connected by a third pin 803. Second limiting blocks 902 are provided between the first connecting block 701 and the second connecting block 702, and between the first connecting block 701 and the third connecting block 703, respectively. The second positioning block 202 and the pressing plate 122 of the present invention are both detachable structures, which meet the molding shape requirements of the preform and greatly improve the flexibility of use. The second positioning block 202 can also press the laid second layer of woven fabric 602 and the first layer of woven fabric 601, which is conducive to laying subsequent woven fabrics, and the degree of pressing of the second positioning block 202 and the pressing plate 122 can be determined by the height of the second limit block 902 to avoid the problem of excessive pressing.

[0051] Installation process of upper mold 1 and lower mold 2; (1) After the preform is laid in lower mold 2, remove the second pin 802 and the corresponding second limit block 902, and remove the second positioning block 202 from the first positioning block 201; (2) The connecting plate 121 and the pressing plate 122 are in contact and pressed with the corresponding braid, and the first pin 801 passes through the connecting plate 121, the third positioning block 203 and the first positioning block 201 in sequence. At this time, one end of the second layer of braid 602 is folded 180° and laid on the pressing plate 122, and the fifth layer of braid 605 is laid on top of the first layer of braid 601 and the second layer of braid 602, and the braid laid on the pressing plate 122 is tightly sewn: (3) The first pressing block 101 is placed on top of the connecting plate 121, and the first pressing block 101 is clamped in the connecting slot 123, and the first pressing block 101 is in contact and pressed with the fifth layer of braid 605.

[0052] Considering that the turbine outer ring preform is small in size and has a complex structure, it needs to be stacked and laid layer by layer, and the corresponding woven fabrics are all strips of cloth with no fixed shape. Therefore, during the molding process of the preform, not only does the mold need to meet the shape requirements of the preform, but the mold also needs to be easy to adjust and position. In view of the shape of the preform, the present invention designs the mold into a structure that is used in conjunction with an upper mold 1 and a lower mold 2, and the structure of the lower mold 2 is three detachable positioning blocks, so that the corresponding woven fabrics can be laid layer by layer, and the corresponding positioning blocks are provided with suture holes 3. Each time a layer of woven fabric is laid, the corresponding parts can be sutured, so that the woven fabrics are not easily separated or broken, and the woven fabrics and the positioning blocks are not easily separated or broken, reducing the degree of distortion during the stacking of the woven fabrics. This is not only beneficial for the subsequent vapor deposition treatment of the preform, but also beneficial for improving the molding accuracy of the preform. Through this flexible molding mold, a turbine outer ring preform with high dimensional accuracy requirements can be prepared.

[0053] Please refer to Figure 7 The lower mold 1 is pressed against the lower mold 2 via the reinforcement frame 5. The first positioning block 201, the third positioning block 203, and the upper mold 1 are connected in sequence. The reinforcement frame 5 is arranged horizontally, and the bottom inner wall of the reinforcement frame 5 is connected to the first positioning block 201. The inner wall of one side of the reinforcement frame 5 is respectively connected to the first end 211 and the corresponding upper mold 1. A first limit block 901 is respectively provided between the inner wall of the other side of the reinforcement frame 5 and the second end 212 and between the corresponding upper molds 1. A second limit block 902 is provided between the top inner wall of the reinforcement frame 5 and the corresponding upper mold 1. There are two reinforcement frames 5, each located on either side of the upper mold 1 and the lower mold 2, and the two reinforcement frames 5 are arranged parallel to each other. After the upper mold 1 and the lower mold 2 are pressed together, the braided fabric is sewn to the upper mold 1 and the lower mold 2 respectively, the base 4 is removed from the first positioning block 201, and the upper mold 1 and the lower mold 2 are framed with a reinforcement frame. The gap between the upper mold 1 and the lower mold 2 is limited and filled with the first limit block 901 and the second limit block 902. The reinforcement frame 5 can prevent the upper mold 1 from separating from the lower mold 2, increase the connection strength between the upper mold 1 and the lower mold 2, and ensure that the preform does not suffer serious displacement during the vapor deposition process.

[0054] A process for forming a turbine outer ring preform mold comprises the following steps:

[0055] S1: Place the base 4 on a horizontal workbench, embed the first end 211 and the second end 212 in the base 4 respectively, lay the first layer of braid 601 and the second layer of braid 602 on the first positioning block 201 from bottom to top, lay the filling braid 606 in the gaps formed by the corresponding braids, and simply sew the corresponding fitting parts of the braids to the first positioning block 201;

[0056] S2: placing the second positioning block 202 on the second layer of braided fabric 602 and connecting the second positioning block 202 to the first positioning block 201;

[0057] S3: Lay a third layer of braided fabric 603 on the third positioning block 203, connect the third positioning block 203 to the base 4, and place the third layer of braided fabric 603 between the first layer of braided fabric 601 and the second layer of braided fabric 602. Lay a filling braided fabric 606 in the gaps formed by the corresponding braided fabrics, and simply sew the corresponding fitting parts of the braided fabrics to the third positioning block 203 and the first positioning block 201 as a whole.

[0058] S4: Laying the fourth layer of braid 604 between the second layer of braid 602 and the third layer of braid 603, laying the filling braid 606 in the gaps formed by the corresponding braids, and sewing the corresponding fitting parts of the braids tightly to the third positioning block 203;

[0059] S5: The second positioning block 202 is removed from the first positioning block 201, and the corresponding upper mold 1 is pressed together with the third positioning block 203. The second layer of braid 602 is folded at a certain angle and laid on the corresponding upper mold 1. The fifth layer of braid 605 is laid on top of the first layer of braid 601 and the second layer of braid 602. The filling braid 606 is laid in the gap formed by the corresponding braids. The corresponding fitting parts of the braids are tightly sewn to the corresponding upper mold 1 and the first positioning block 201 as a whole.

[0060] S6: Press the corresponding upper mold 1 and the first positioning block 201 to obtain a preform, remove the base 4, and use chemical vapor deposition to obtain a turbine outer ring blank.

[0061] The first, second, third, fourth, and fifth braid layers 601, 602, 603, 604, and 605 are made of silicon carbide or carbon cloth, and the sewing thread is made of 1K or 3K carbon fiber. Silicon carbide or carbon cloth can be used to prepare preforms of various shapes and sizes, and also offers the advantages of low density, high temperature resistance, oxidation resistance, ablation resistance, and resistance to catastrophic damage, meeting the requirements for turbine outer rings.

[0062] It is worth noting that the second positioning block 202 and the base 4 are metal forming auxiliary tooling, and their materials are all metal materials. Before high-temperature vapor deposition, the second positioning block 202 and the base 4 need to be disassembled; the remaining structural materials of the mold are all graphite materials, that is, the first pressing block 101, the second pressing block 102, the first positioning block 201, the third positioning block 203, the reinforcement frame 5, the first connecting block 701, the third connecting block 703, the first pin shaft 801, the second pin shaft 802, the third pin shaft 803, the first limit block 901, the second limit block 902 and the third limit block 903 are all made of graphite.

[0063] The above are only preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.

Claims

1. A forming process based on a turbine outer ring preform forming die, characterized in that: The following steps are involved: The molding die comprises: a base (4) and an upper die (1) and a lower die (2) for pressing and molding the preform; The lower mold (2) comprises a first positioning block (201), a second positioning block (202) and a third positioning block (203); the first positioning block (201) is arranged transversely, and comprises a first end (211) and a second end (212) respectively connected to the base (4); the second positioning block (202) is arranged above the first end (211) at intervals, and the second positioning block (202) is detachably connected to the first positioning block (201); the third positioning block (203) is arranged above the second end (212) at intervals, and the third positioning block (203) is detachably connected to the base (4), and the third positioning block (203) is arranged opposite to the second positioning block (202); The upper mold (1) is pressed together with the corresponding first positioning block (201) and third positioning block (203), and the first positioning block (201), the third positioning block (203) and the upper mold (1) are all provided with suture holes (3) for sewing the corresponding braided fabric; S1: The base (4) is placed on a horizontal workbench, the first end (211) and the second end (212) are respectively embedded in the base (4), the first layer of braided fabric (601) and the second layer of braided fabric (602) are laid on the first positioning block (201) from bottom to top, the gaps formed by the corresponding braided fabrics are laid with filling braided fabric (606), and the corresponding fitting parts of the braided fabrics are simply sewn to the first positioning block (201); S2: placing the second positioning block (202) on the second layer of braided fabric (602), and connecting the second positioning block (202) to the first positioning block (201); S3: laying a third layer of braided fabric (603) on the third positioning block (203), connecting the third positioning block (203) to the base (4), the third layer of braided fabric (603) being located between the first layer of braided fabric (601) and the second layer of braided fabric (602), laying a filling braided fabric (606) in the gap formed by the corresponding braided fabrics, and simply sewing the corresponding fitting parts of the braided fabrics to the third positioning block (203); S4: Laying a fourth layer of braided fabric (604) between the second layer of braided fabric (602) and the third layer of braided fabric (603), laying a filling braided fabric (606) in the gaps formed by the corresponding braided fabrics, and tightly sewing the corresponding fitting parts of the braided fabrics to the third positioning block (203) and the first positioning block (201) as a whole; S5: The second positioning block (202) is removed from the first positioning block (201), the corresponding upper mold (1) is pressed together with the third positioning block (203), the second layer of braid (602) is folded at a certain angle and laid on the corresponding upper mold (1), the fifth layer of braid (605) is laid on top of the first layer of braid (601) and the second layer of braid (602), the filling braid (606) is laid in the gap formed by the corresponding braid, and the corresponding fitting part of the braid is tightly sewn to the corresponding upper mold (1) and the first positioning block (201); S6: Pressing the corresponding upper mold (1) and the first positioning block (201) together to obtain a preform, removing the base (4), and using a chemical vapor deposition method to obtain a turbine outer ring blank.

2. The forming process based on the turbine outer ring preform forming die according to claim 1 is characterized in that: The upper mold (1) comprises a first pressing block (101) and a second pressing block (102) connected to each other, wherein the first pressing block (101) is arranged above the first end (211), and the second pressing block (102) is located between the third positioning block (203) and the first pressing block (101), and an end of the second pressing block (102) close to the second end (212) is detachably connected to the third positioning block (203), and an end of the second pressing block (102) close to the first end (211) is connected to the first pressing block (101).

3. The forming process based on the turbine outer ring preform forming die according to claim 2 is characterized in that: The second pressing block (102) comprises a connecting plate (121) and a pressing plate (122) connected to each other, the connecting plate (121) being located between the third positioning block (203) and the first pressing block (101), the pressing plate (122) being located between the first positioning block (201) and the first pressing block (101), the pressing plate (122) being arranged opposite to the third positioning block (203), and the pressing plate (122) being provided with the suture hole (3).

4. The forming process based on the turbine outer ring preform forming die according to claim 3 is characterized in that: A connecting slot (123) is provided on the top of the connecting plate (121), and the first pressing block (101) is clamped in the connecting slot (123); the connecting plate (121), the third positioning block (203) and the first positioning block (201) are connected via a first pin shaft (801).

5. The forming process based on the turbine outer ring preform forming die according to claim 3 is characterized in that: A first connecting block (701) is provided on both sides of the first positioning block (201), and a second connecting block (702) is provided on both sides of the second positioning block (202), and the first connecting block (701) and the second connecting block (702) are connected via a second pin shaft (802); a third connecting block (703) is provided on both sides of the pressing plate (122), and the first connecting block (701) and the third connecting block (703) on the same side are connected via a third pin shaft (803); a third limiting block (903) is provided between the first connecting block (701) and the second connecting block (702), and between the first connecting block (701) and the third connecting block (703).

6. The forming process based on the turbine outer ring preform forming die according to claim 1 is characterized in that: The upper mold (1) is pressed together with the lower mold (2) through the reinforcement frame (5); the first positioning block (201), the third positioning block (203) and the upper mold (1) are connected in sequence; the reinforcement frame (5) is arranged horizontally; the bottom inner wall of the reinforcement frame (5) is connected to the first positioning block (201); the inner wall of one side of the reinforcement frame (5) is connected to the first end (211) and the corresponding upper mold (1); a first limiting block (901) is provided between the inner wall of the other side of the reinforcement frame (5) and the second end (212) and between the corresponding upper mold (1); and a second limiting block (902) is provided between the top inner wall of the reinforcement frame (5) and the corresponding upper mold (1).

7. The forming process based on the turbine outer ring preform forming die according to claim 6 is characterized in that: The number of the reinforcement frames (5) is 2, and the two reinforcement frames (5) are respectively located on both sides of the upper mold (1) and the lower mold (2), and the two reinforcement frames (5) are arranged parallel to each other.

8. The forming process based on the turbine outer ring preform forming die according to claim 1 is characterized in that: The first layer of braid (601), the second layer of braid (602), the third layer of braid (603), the fourth layer of braid (604) and the fifth layer of braid (605) are made of silicon carbide cloth or carbon cloth.

9. The forming process based on the turbine outer ring preform forming die according to claim 1 is characterized in that: The thread used for sewing is made of 1K or 3K carbon fiber.

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