SiC / sic ceramic matrix composite turbine blade whole ring processing tool and method

Abstract

This invention relates to turbine blade assembly fixtures and methods, specifically to a fixture and method for machining a complete ring of SiC / SiC ceramic matrix composite turbine blades. It solves the technical problem of poor dimensional and surface consistency when assembling existing SiC / SiC ceramic matrix composite turbine blades into a complete ring. The fixture of this invention includes a front machining fixture and a back machining fixture. The front machining fixture includes a front base, multiple first pressure plates, a support ring, and a first pressure plate. The front base has a cylindrical boss. The support ring is fitted onto the outer surface of the cylindrical boss, and the first pressure plate and the support ring press a reference boss. The first pressure plates are used to press a third boss onto the front base. The back machining fixture includes a back base, fasteners, a second pressure plate, and multiple second pressure plates. A cylindrical boss is located at the center of the back base. The second pressure plate is located on the upper surface of the cylindrical boss and is used to press a reference boss onto it using fasteners. The second pressure plates are used to press a second boss onto the back base.

Description

Technical Field

[0001] This invention relates to turbine blade assembly fixtures and methods, specifically to a tooling and method for machining the ring of a SiC / SiC ceramic matrix composite turbine blade. Background Technology

[0002] Continuous fiber-reinforced SiC / SiC ceramic matrix composites (hereinafter referred to as SiC / SiC) are considered the preferred material for hot-end components of aerospace engines due to their excellent physical and chemical properties, including high temperature resistance, oxidation resistance, thermal shock resistance, low density, and high strength. In particular, their high-temperature oxidation resistance is superior to that of continuous fiber-reinforced C / SiC ceramic matrix composites (hereinafter referred to as C / SiC). Currently, publicly available information shows that SiC / SiC gas turbine blades mostly adopt a riveted assembly structure. Chinese patent CN111102017A discloses a single-unit assembled fixed guide vane structure and its molding method, which divides the fixed guide vane into three parts: an inner edge plate, a blade body, and an outer edge plate. The inner and outer edge plates are further divided into three parts each, and the product is finally assembled by riveting. Chinese patent CN110966049A discloses a three-unit assembled fixed guide vane structure and its molding method. As is well known, turbine blades need to be assembled into a complete circle when in use. The assembled structure of the blades inevitably has problems with the consistency of size and profile. At present, the common problems are mainly as follows:

[0003] 1. Individual products are dimensionally acceptable, but when assembled into a complete ring, there are dimensional deviations and interference between the splicing surfaces;

[0004] 2. If the size of a single blade is too small, the positioning reference and machining reference surface will be too small during processing and assembly, and the accuracy cannot be guaranteed.

[0005] 3. When assembling individual blade products into a complete ring, there is a phenomenon of inconsistent dimensions in the circumferential direction. Summary of the Invention

[0006] The purpose of this invention is to solve the technical problem of poor dimensional and surface consistency when assembling SiC / SiC ceramic matrix composite turbine blades from individual blades into a complete ring, and to provide a tooling and method for machining SiC / SiC ceramic matrix composite turbine blades into a complete ring.

[0007] The technical solution of this invention is:

[0008] A tooling for machining the ring of a SiC / SiC ceramic matrix composite turbine blade, the blade comprising a blade body and inner and outer edge plates respectively disposed at both ends of the blade body; the outer side wall of the inner edge plate is provided with an extended first boss near the top and an extended reference boss in the middle; the outer side wall of the outer edge plate is provided with a second boss at the upper part and a third boss at the bottom; its special feature is that it includes a front machining tooling and a back machining tooling.

[0009] The front processing fixture includes a front base, multiple first pressure plates, a support ring, and a first pressure plate disposed on the front base; the front base is a hollow disc structure with a coaxial cylindrical boss at its center; an annular area on the front base between the first pressure plates and the support ring is used to place multiple blades in a ring; the inner diameter of the support ring is adapted to the outer diameter of the cylindrical boss, and the support ring is fixedly sleeved on the outer surface of the cylindrical boss; the upper end face of the support ring is adapted to the lower surface face of the reference boss; the outer wall of the first pressure plate is provided with a stepped structure along the circumference, with the upper end being the large end and the lower end being the small end, and the transverse stepped surface of the first pressure plate is adapted to the upper surface face of the reference boss, and the first pressure plate and the support ring press the reference boss together; the multiple first pressure plates are arranged circumferentially on the upper surface of the front base, the outer ends of the first pressure plates are fixedly connected to the front base, and their inner ends are used to press the third boss onto the front base;

[0010] The reverse processing fixture includes a reverse base, fasteners, a second pressure plate and multiple second pressure plates disposed on the reverse base; the reverse base is a hollow disc structure with a coaxial cylindrical boss at its center; multiple blades are arranged in a circumferential direction between the cylindrical boss and the second pressure plate; a first groove is provided on the reverse base to avoid the lower structure of the blades; the second pressure plate is disposed on the upper surface of the cylindrical boss, the outer diameter of the second pressure plate is larger than the outer diameter of the cylindrical boss, and the upper surface profile of the second pressure plate near the edge is adapted to the upper surface of the reference boss, for pressing the reference boss with fasteners; the multiple second pressure plates are arranged circumferentially on the upper surface of the reverse base, the outer ends of the second pressure plates are fixed to the reverse base, and their inner ends are used to press the second bosses onto the reverse base.

[0011] Furthermore, a second groove is provided on the front base at the position of the support ring, which is used to adjust the support ring up and down according to different blade specifications and sizes.

[0012] Furthermore, the cylindrical boss of the front base has a waist-shaped hole on its side wall for fixing the front base and the support ring. The length of the waist-shaped hole meets the requirements for adjusting the support ring up and down.

[0013] Furthermore, the distance between the bottom surface of the second groove and the bottom surface of the front base is 5-10 mm.

[0014] Furthermore, the front machining fixture also includes multiple bolts; the fasteners of the reverse machining fixture are multiple bolts; and the reference boss is provided with positioning reference holes.

[0015] The first pressure plate is fixedly connected to the front base by screws; the first pressure plate, the support ring and the front base are all provided with multiple threaded holes corresponding to the positioning reference holes of multiple blades. Bolts are sequentially inserted into the threaded holes of the first pressure plate, the positioning reference holes, the threaded holes of the support ring and the threaded holes of the front base to press the reference boss tight; the second pressure plate and the back base are provided with multiple threaded holes corresponding to the positioning reference holes of multiple blades. Bolts are sequentially inserted into the positioning reference holes, the threaded holes of the second pressure plate and the back base to press the reference boss tight.

[0016] Furthermore, both the front base and the back base are provided with weight reduction holes; both the first pressure plate and the second pressure plate are L-shaped structures, and the short end of the L-shaped structure is fixedly connected to the front base or the back base.

[0017] Meanwhile, this invention also provides a method for machining a complete ring of SiC / SiC ceramic matrix composite turbine blades, using the aforementioned tooling, characterized by the following steps:

[0018] 1) Use the upper and lower surfaces of the blade's reference boss as the upper and lower reference surfaces and machine them to the theoretical dimensions respectively, and then complete the machining of multiple blades of the entire ring in sequence.

[0019] 2) Install the front base onto the processing table to ensure that the flatness of the upper surface of the front base meets the standard;

[0020] 3) Install the support ring onto the front base;

[0021] 4) Install the processed blades onto the support ring, so that the lower reference surface of the reference boss of each blade is in contact with the corresponding plane of the support ring, and the bottom plane of the outer edge plate of each blade is in contact with the corresponding plane on the front base. Then fix the support ring to the front base.

[0022] 5) Fit the transverse stepped surface of the first pressure plate with the upper reference surface of the reference boss of the multiple blades, and fix the first pressure plate and the support ring together.

[0023] 6) Press the inner ends of the multiple first pressure plates onto the corresponding third protrusions, and fix the first pressure plates to the front base;

[0024] 7) Using a CNC milling machine, remove the excess material from the outer side and top of the inner edge plate and the outer side and top of the outer edge plate according to the theoretical numerical model and the pre-programmed machining program;

[0025] 8) Remove the first pressure plate and support ring in sequence, attach the reverse base to the second pressure plate, align the mounting holes, and place the blade upside down on the initially attached reverse base and second pressure plate; the first pressure plate and the second pressure plate can be structurally identical. Before removing the front machining fixture, bond the blade reference surface to the first pressure plate, then remove the connecting bolts, support ring and front base, attach the reverse side of the first pressure plate to the reverse base, and tighten it with bolts;

[0026] 9) Use a second pressing plate to fix the blade to the reverse base;

[0027] 10) Remove the first pressure plate and the front base in sequence;

[0028] 11) Secure the reference surface of each blade to the second pressure plate and the reverse base using fastener bolts;

[0029] 12) According to the theoretical numerical model and the CNC machining program, remove the excess material from the bottom of the inner edge plate, the lower outer arc surface of the outer edge plate, and the bottom plane; after the entire ring blade is machined, remove the tooling.

[0030] Furthermore, in step 2), the flatness of the upper surface of the front base reaches 0.02 to 0.1.

[0031] Furthermore, in step 4), when machining turbine blades of different specifications and sizes, the upper and lower support rings are adjusted to accommodate the turbine blades.

[0032] The beneficial effects of this invention are:

[0033] 1. This invention relates to a machining fixture for complete rings of SiC / SiC ceramic matrix composite turbine blades. A dedicated assembly fixture for complete rings of SiC / SiC ceramic matrix composite turbine blades is designed, ensuring consistent machining datums. With the assistance of this fixture, the machining datums of all blades are controlled to be the same. A mating method using front and back bases ensures that the datum remains unchanged during the blade product machining process. While maintaining the datum surface and datum hole, the remaining allowance of the blade product is then machined as a whole, effectively ensuring dimensional consistency during the blade assembly process after machining. This improves the overall dimensional accuracy and overall performance of the complete ring blade, thereby effectively enhancing the airflow sealing performance of the complete ring turbine blade during testing.

[0034] 2. The present invention provides a ring-shaped machining fixture for SiC / SiC ceramic matrix composite turbine blades. The ring-shaped machining fixture is circular, which is easy to assemble and position, and has high machining efficiency. It can be quickly installed and positioned by positioning reference holes and fitting reference surfaces.

[0035] 3. The tooling for machining the SiC / SiC ceramic matrix composite turbine blade ring of the present invention has an adjustable support ring on the mounting reference surface to meet the machining requirements of turbine blades of different specifications and sizes.

[0036] 4. The tooling for machining the SiC / SiC ceramic matrix composite turbine blade ring of the present invention is provided with weight reduction holes, which reduces the overall weight.

[0037] 5. The present invention provides a unified machining datum for the SiC / SiC ceramic matrix composite turbine blade ring, ensuring the consistency of the mounting datum surface of the ring blade. Under the premise of keeping the datum surface and datum hole unchanged, the theoretical numerical model and machining program are used to process the product allowance of the ring blade as a whole, which effectively ensures the dimensional consistency of the blade assembly process after machining, and improves the overall dimensional accuracy and overall performance of the ring blade. At the same time, the machining sequence of first machining the positioning datum and then machining the allowance around the edge plate ensures the dimensional accuracy of the blade mating gap and mating surface. Attached Figure Description

[0038] Figure 1 This is a schematic diagram of the structure of a SiC / SiC ceramic matrix composite turbine blade. Figure 1 ;

[0039] Figure 2 This is a schematic diagram of the structure of a SiC / SiC ceramic matrix composite turbine blade. Figure 2 ;

[0040] Figure 3 This is an exploded view of an embodiment of the front machining tooling of the present invention;

[0041] Figure 4 This is a schematic diagram of the structure of an embodiment of the front machining tooling of the present invention;

[0042] Figure 5 This is an exploded view of the front machining tooling of the present invention, with turbine blades assembled thereon.

[0043] Figure 6 This is an exploded view of an embodiment of the reverse side machining tooling of the present invention;

[0044] Figure 7 This is a schematic diagram of the structure of an embodiment of the reverse side processing tooling of the present invention;

[0045] Figure 8 This is an exploded view of the reverse machining tooling of the present invention, with turbine blades assembled thereon.

[0046] Figure 9 This is a schematic diagram of the front machining tooling assembly of the complete ring turbine blade of the present invention;

[0047] Figure 10 This is a schematic diagram of the structure of the reverse machining tooling for assembling the complete ring turbine blades of the present invention.

[0048] Reference numerals: 01-blade, 02-inner edge plate, 021-reference boss, 0211-upper reference surface, 0212-lower reference surface, 022-positioning reference hole, 023-first boss, 03-outer edge plate, 031-second boss, 032-third boss, 04-upper area, 05-lower area, 06-blade body; 1-front base, 2-first pressure plate, 3-screw, 4-support ring, 5-bolt, 6-first pressure plate; 7-reverse base, 8-second pressure plate, 9-second pressure plate. Detailed Implementation

[0049] The present invention will now be described in detail with reference to the accompanying drawings and embodiments.

[0050] The tooling of this invention is designed for SiC / SiC ceramic matrix composite turbine blades, the blade structure of which is as follows: Figure 1 and Figure 2 As shown, the blade 01 includes a blade body 06 and an inner edge plate 02 and an outer edge plate 03 respectively disposed at both ends of the blade body 06; the outer side wall of the inner edge plate 02 is provided with an extended first boss 023 near the top position and an extended reference boss 021 in the middle, and the reference boss 021 is provided with a positioning reference hole 022; the outer side wall of the outer edge plate 03 is provided with a second boss 031 at the upper part and a third boss 032 at the bottom.

[0051] The machining of a complete turbine blade ring can be divided into two steps: front machining and back machining. Therefore, this invention provides a machining fixture for the complete ring of a SiC / SiC ceramic matrix composite turbine blade, including a front machining fixture and a back machining fixture. Front machining refers to the machining of... Figure 2 The upper region 04 shown is the reverse side processing. Figure 2 The lower region 05 is shown in the diagram.

[0052] like Figure 3 and Figure 4As shown, the front machining fixture includes a front base 1, multiple first pressure plates 2, a support ring 4, multiple bolts 5, and a first pressure plate 6 mounted on the front base 1. The front base 1 provides a reference for the entire fixture. The front base 1 is a hollow disc structure with a coaxial cylindrical boss at its center. The cylindrical boss provides a positioning reference for the support ring 4 and a support platform for clamping the first pressure plate 6. The annular area on the front base 1 between the first pressure plates 2 and the support ring 4 is used to place multiple blades 01 in a ring. The support ring 4 provides an installation reference surface for the blades 01. It is an annular structure, and the inner diameter of the support ring 4 matches the outer diameter of the cylindrical boss. The support ring 4 is fixedly sleeved on the outer surface of the cylindrical boss. The support ring 4 is designed to be adjustable up and down for fixed connection, so that the reference surface of the blade 01 is in contact with the reference surface and auxiliary plane of the fixture. After adjustment, the support ring 4 is fastened to the front base 1 using bolts. The upper end face of the support ring 4 matches the lower surface face of the reference boss 021. The first pressure plate 6 is located at the top of the front machining fixture. It has a circular ring structure. The outer wall of the first pressure plate 6 is provided with a stepped structure along the circumference. The upper end is the large end and the lower end is the small end. The transverse stepped surface of the first pressure plate 6 is adapted to the upper surface profile of the reference boss 021. The lower bottom surface of the small end of the first pressure plate 6 is in contact with the upper end surface of the support ring 4 and the upper end surface of the cylindrical boss of the front base 1. The first pressure plate 6, the support ring 4 and the front base 1 are all provided with multiple threaded holes corresponding to the positioning reference holes 022 of the multiple blades 01. The bolts 5 are inserted into the threaded holes of the first pressure plate 6, the positioning reference holes 022, the threaded holes of the support ring 4 and the threaded holes of the front base 1 in sequence to press the reference boss 021. Multiple first pressure plates 2 are arranged circumferentially on the upper surface of the front base 1. The outer end of the first pressure plate 2 is fixed to the front base 1 by screws 3, and its inner end is used to press the third boss 032 onto the front base 1. A second groove is provided on the front base 1 at the position of the support ring 4, which increases the downward adjustment range of the support ring 4. This allows the support ring 4 to be adjusted up and down according to different blade 01 specifications and sizes, meeting the processing needs of blade products with different specifications and sizes. The distance between the bottom surface of the second groove and the bottom surface of the front base 1 is 5-10mm. The cylindrical boss of the front base 1 has an oblong hole on its side wall for fixing the front base 1 and the support ring 4. The length of the oblong hole meets the vertical adjustment requirements of the support ring 4. Figure 5 An exploded view of the assembly of the ring blade 01 for front machining tooling.

[0053] When machining the reverse side of a complete ring blade, the entire ring blade needs to be flipped up and down to achieve the purpose of machining the bottom allowance of the blade product. For example... Figure 6 and Figure 7As shown, the reverse machining fixture includes a reverse base 7, fasteners, a second pressure plate 9 mounted on the reverse base 7, and multiple second pressure plates 8. The reverse base 7 serves as the mounting reference for the reverse machining of the blade 01. The reverse base 7 is a hollow disc structure with a coaxial cylindrical boss at its center. The cylindrical boss and the second pressure plate 9 are used to place multiple blades 01 in a circumferential arrangement. A first groove is provided on the reverse base 7 to avoid obstructing the lower portion of the blade 01. The structure of the second pressure plate 9 is similar to that of the first pressure plate 6, and the second pressure plate 9 and the first pressure plate 6 can share the same part. The second pressure plate 9 is mounted on the upper surface of the cylindrical boss, and its outer diameter is larger than that of the cylindrical boss. 9 The upper surface profile near the edge is adapted to the upper surface of the reference boss 021; the fasteners of the reverse machining fixture are multiple bolts 5, the second pressure plate 9 and the reverse base 7 are provided with multiple threaded holes corresponding to the positioning reference holes 022 of multiple blades 01, the bolts 5 pass through the positioning reference holes 022, the second pressure plate 9 and the threaded holes of the reverse base 7 in sequence to press the reference boss 021; multiple second pressure plates 8 are arranged circumferentially on the upper surface of the reverse base 7, the outer end of the second pressure plate 8 is fixed to the reverse base 7, and its inner end is used to press the second boss 031 onto the reverse base 7. Figure 8 An exploded view of the assembly of the ring blade 01 for reverse machining tooling.

[0054] Both the front base 1 and the back base 7 are provided with weight reduction holes; the first pressure plate 2 and the second pressure plate 8 are both L-shaped structures with through holes for screws 3 to pass through, and the short end of the L-shaped structure is fixedly connected to the front base 1 or the back base 7.

[0055] This invention also provides a method for machining a complete ring of SiC / SiC ceramic matrix composite turbine blades, using the aforementioned tooling, and including the following steps:

[0056] 1) Machining reference surface

[0057] The upper and lower surfaces of the reference boss 021 of the assembled blade 01 are used as the upper and lower reference surfaces, and are machined to the theoretical size on a CNC milling machine. During machining, the upper reference surface 0211 is first milled flat with a diamond end mill, and then the blade 01 is rotated 180°. The lower reference surface 0212 is machined with the machined upper reference surface 0211 as the reference. The reference surfaces of the complete ring blade 01 are machined in this way.

[0058] 2) Level the front base 1, install and fix the front base 1 to the machine tool worktable, and use a dial indicator to check the flatness of the upper surface of the front base 1 so that the flatness reaches 0.02~0.1.

[0059] 3) Install the support ring 4 onto the front base 1; during installation, make the inner side of the support ring 4 fit against the outer side of the cylindrical boss of the front base 1, and then use bolts 5 to pass through the waist-shaped hole on the side of the cylindrical boss of the front base 1 to connect the front base 1 and the support ring 4.

[0060] 4) Install the processed blades 01 onto the support ring 4.

[0061] Adjust the up and down position of the support ring 4 so that the lower reference surface 0212 of the reference boss 021 of each blade 01 is in contact with the corresponding upper surface of the support ring 4. Align the positioning reference hole 022 on the reference surface of the inner edge plate 02 with the threaded hole on the support ring 4. Then make the bottom plane of the outer edge plate 03 of each blade 01 in contact with the corresponding plane on the front base 1, without any warping or local contact. Then fix the support ring 4 to the front base 1.

[0062] 5) Install the first pressure plate 6

[0063] Align the mounting holes on the first pressure plate 6 with the positioning reference holes 022 on the corresponding blade 01, attach the transverse step surface of the first pressure plate 6 to the upper reference surface 0211 of the reference boss 021 of the multiple blades 01, attach the outer arc surface of the inner edge plate 02 of the blade 01 to the vertical step surface of the first pressure plate 6, thereby achieving the positioning of the blade 01 in the circumferential direction, and fixing the first pressure plate 6 and the support ring 4 together.

[0064] 6) Install the first tablet press 2

[0065] To ensure the stability of blade 01 during processing, the bottom of the outer edge plate 03 of blade 01 needs to be pressed tightly, the outer end of the first pressing plate 2 needs to be attached to the front base 1, the inner ends of multiple first pressing plates 2 need to be pressed onto the third protrusion 032 at the corresponding positions, and the first pressing plate 2 needs to be fixed to the front base 1 using screws 3.

[0066] 7) Machining allowance on the front side

[0067] Using a CNC milling machine, the excess material on the outer side and top of the inner edge plate 02 and the outer side and top of the outer edge plate 03 is removed according to the theoretical numerical model and the pre-programmed machining program.

[0068] 8) Install the reverse base 7

[0069] Remove the first pressure plate 6 and support ring 4 in sequence. Fit the reverse base 7 with the second pressure plate 9, aligning the mounting holes. Place the blade 01 upside down on the initially fitted reverse base 7 and second pressure plate 9. To prevent the clamped blade 01 from shifting position, temporarily tighten or glue it. When the first pressure plate 6 and second pressure plate 9 are the same part, do not remove the first pressure plate 6; only remove the support ring 4 before installing the reverse base 7.

[0070] 9) Install the second tablet 8

[0071] The blade 01 is fixed to the reverse base 7 using the second pressure plate 8. Depending on the product size, each blade 01 can be equipped with 2 to 4 second pressure plates 8.

[0072] 10) Remove the first pressing plate 2 and the front base 1 in sequence;

[0073] 11) Secure the reference surface of each blade 01 to the second pressure plate 9 and the reverse base 7 using fastener bolts 5;

[0074] 12) Machining allowance for the bottom surface of blade 01

[0075] According to the theoretical numerical model and the compiled CNC machining program, the excess material at the bottom of the inner edge plate 02, the lower outer arc surface of the outer edge plate 03, and the bottom plane is removed; the entire ring blade 01 is machined and the tooling is removed.

Claims

1. A tooling for machining a complete ring of a SiC / SiC ceramic matrix composite turbine blade, the blade (01) comprising a blade body (06) and an inner edge plate (02) and an outer edge plate (03) respectively disposed at both ends of the blade body (06); the outer side wall of the inner edge plate (02) is provided with an extended first boss (023) near the top and an extended reference boss (021) in the middle; the outer side wall of the outer edge plate (03) is provided with a second boss (031) at the upper part and a third boss (032) at the bottom; characterized in that: Including front-side machining fixtures and back-side machining fixtures; The front processing fixture includes a front base (1), multiple first pressure plates (2), a support ring (4), and a first pressure plate (6) disposed on the front base (1); the front base (1) is a hollow disc structure with a coaxial cylindrical boss at its center; the annular area on the front base (1) between the first pressure plates (2) and the support ring (4) is used to place multiple blades (01) in a ring; the inner diameter of the support ring (4) is adapted to the outer diameter of the cylindrical boss, and the support ring (4) is fixedly sleeved on the outer surface of the cylindrical boss; the upper end face of the support ring (4) is aligned with the base. The lower surface of the quasi-protrusion (021) is adapted to the profile; the outer wall of the first pressure plate (6) is provided with a stepped structure along the circumference, with the upper end being the large end and the lower end being the small end. The transverse stepped surface of the first pressure plate (6) is adapted to the upper surface of the reference protrusion (021). The first pressure plate (6) and the support ring (4) press the reference protrusion (021) tightly; the plurality of first pressure plates (2) are arranged along the circumference on the upper surface of the front base (1). The outer end of the first pressure plate (2) is fixedly connected to the front base (1), and its inner end is used to press the third protrusion (032) onto the front base (1); The reverse processing fixture includes a reverse base (7), fasteners, a second pressure plate (9) disposed on the reverse base (7), and multiple second pressure plates (8); the reverse base (7) is a hollow disc structure with a coaxial cylindrical boss at its center; multiple blades (01) are placed in a circumferential ring between the cylindrical boss and the second pressure plate (9); a first groove is provided on the reverse base (7) to avoid the lower structure of the blades (01); the second pressure plate (9) is provided with... On the upper surface of the cylindrical boss, the outer diameter of the second pressure plate (9) is larger than the outer diameter of the cylindrical boss. The upper surface profile of the second pressure plate (9) near the edge is adapted to the upper surface of the reference boss (021) and is used to press the reference boss (021) tightly by fasteners. The plurality of second pressure plates (8) are arranged circumferentially on the upper surface of the reverse base (7). The outer end of the second pressure plate (8) is fixed to the reverse base (7), and its inner end is used to press the second boss (031) onto the reverse base (7).

2. The tooling for machining the complete ring of SiC / SiC ceramic matrix composite turbine blades according to claim 1, characterized in that: The front base (1) is provided with a second groove at the position of the support ring (4) for the support ring (4) to be adjusted up and down according to the different blade (01) specifications and sizes.

3. The tooling for machining the complete ring of SiC / SiC ceramic matrix composite turbine blades according to claim 2, characterized in that: The cylindrical boss of the front base (1) has a waist-shaped hole on its side wall for fixing the front base (1) and the support ring (4). The length of the waist-shaped hole meets the requirements for the up and down adjustment of the support ring (4).

4. The tooling for machining the complete ring of SiC / SiC ceramic matrix composite turbine blades according to claim 3, characterized in that: The distance between the bottom surface of the second groove and the bottom surface of the front base (1) is 5-10 mm.

5. The tooling for machining the complete ring of SiC / SiC ceramic matrix composite turbine blades according to claim 4, characterized in that: The front machining fixture also includes multiple bolts (5); the fasteners of the reverse machining fixture are multiple bolts (5); the reference boss (021) is provided with a positioning reference hole (022); The first pressure plate (2) is fixedly connected to the front base (1) by screws (3); the first pressure plate (6), the support ring (4) and the front base (1) are all provided with multiple threaded holes corresponding to the positioning reference holes (022) of the multiple blades (01), and the bolts (5) are sequentially inserted into the threaded holes of the first pressure plate (6), the positioning reference holes (022), the threaded holes of the support ring (4) and the threaded holes of the front base (1) to press the reference boss (021); the second pressure plate (9) and the reverse base (7) are provided with multiple threaded holes corresponding to the positioning reference holes (022) of the multiple blades (01), and the bolts (5) are sequentially inserted into the positioning reference holes (022), the second pressure plate (9) and the threaded holes of the reverse base (7) to press the reference boss (021).

6. The tooling for machining the ring of SiC / SiC ceramic matrix composite turbine blades according to claim 5, characterized in that: Both the front base (1) and the back base (7) are provided with weight reduction holes; the first pressure plate (2) and the second pressure plate (8) are both L-shaped structures, and the short end of the L-shaped structure is fixedly connected to the front base (1) or the back base (7).

7. A method for machining a complete ring of SiC / SiC ceramic matrix composite turbine blades, using the tooling described in any one of claims 1-6, characterized in that, Includes the following steps: 1) The upper and lower surfaces of the reference boss (021) of the blade (01) are used as the upper and lower reference surfaces and machined to the theoretical size respectively, and the machining of multiple blades (01) of the whole ring is completed in sequence. 2) Install the front base (1) onto the processing table to ensure that the flatness of the upper surface of the front base (1) meets the standard; 3) Install the support ring (4) onto the front base (1); 4) Install the processed blades (01) onto the support ring (4), so that the lower reference surface (0212) of the reference boss (021) of each blade (01) fits with the corresponding plane of the support ring (4), and the bottom plane of the outer edge plate (03) of each blade (01) fits with the corresponding plane on the front base (1). Then fix the support ring (4) to the front base (1). 5) The transverse step surface of the first pressure plate (6) is attached to the upper reference surface (0211) of the reference boss (021) of the multiple blades (01), and the first pressure plate (6) and the support ring (4) are fixedly connected. 6) Press the inner ends of multiple first pressure plates (2) onto the corresponding third protrusions (032) and fix the first pressure plates (2) to the front base (1); 7) Using a CNC milling machine, remove the excess material from the outer side and top of the inner edge plate (02) and the outer side and top of the outer edge plate (03) according to the theoretical numerical model and the pre-programmed machining program; 8) Remove the first pressure plate (6) and support ring (4) in sequence, attach the reverse base (7) to the second pressure plate (9), align the mounting holes, and place the blade (01) upside down on the initially attached reverse base (7) and second pressure plate (9); 9) Use the second pressing plate (8) to fix the blade (01) onto the reverse base (7); 10) Remove the first pressing plate (2) and the front base (1) in sequence; 11) Secure the reference surface of each blade (01) to the second pressure plate (9) and the reverse base (7) using fastener bolts (5); 12) According to the theoretical numerical model and the CNC machining program, remove the excess material from the bottom of the inner edge plate (02), the lower outer arc surface of the outer edge plate (03), and the bottom plane; the entire ring blade (01) is machined and the tooling is removed.

8. The method for forming a complete ring of SiC / SiC ceramic matrix composite turbine blades according to claim 7, characterized in that: In step 2), the flatness of the upper surface of the front base (1) reaches 0.02 to 0.

1.

9. The method for forming a complete ring of SiC / SiC ceramic matrix composite turbine blades according to claim 8, characterized in that: In step 4), when processing turbine blades of different specifications and sizes, the upper and lower support rings (4) are adjusted to accommodate the turbine blades.

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