Precision forming method and die for ultra-large type complex turbine disc forge piece

Abstract

The invention provides an ultra-large turbine disc forge piece precision subarea die forging forming method which comprises the following steps that 1, ultra-large turbine disc forge piece forming is divided into two areas including a center hub radial plate area and an outer side radial plate rim area, the center hub radial plate area is mainly formed through pre-forging, and the outer side radial plate rim area is mainly formed through final forging; secondly, based on the first step, a pre-forging cavity is designed, and a center hub, a radial plate area, an outer side radial plate and a rim area are precisely formed; 3, a finish forging cavity is designed and comprises a center hub, a radial plate area, an outer side radial plate and a rim area; 4, on the basis of the steps, through analog simulation, the shapes and sizes of the pre-forging die and the finish-forging die are adjusted according to the ultra-large turbine disc forge piece filling and forming load conditions; and 5, the forming process of the ultra-large turbine disc forge piece is simulated and analyzed, and it is ensured that the pre-forging forming load and the finish-forging forming load are both lower than 800 MN. The problems of high forming load, large machining allowance and the like during traditional forging of the ultra-large turbine disc forge piece are effectively solved.

Description

Technical Field

[0001] The invention relates to a precision forming method and a die for a super-large turbine disc forging, belonging to the technical field of metal forging. Background Art

[0002] The ultra-large turbine discs of heavy-duty gas turbines are mainly used in industrial production, oil and gas industry, power generation industry, etc. However, the ultra-large turbine discs for heavy-duty gas turbines have high forming loads and large machining allowances, making it difficult to achieve precision forming. For example, a high-temperature alloy turbine disc produced by a certain company has a diameter of 2.3 meters and a billet weight of 13.5 tons. It is extremely difficult to form precision discs, and the machining allowance is very large, resulting in extremely low material utilization.

[0003] In response to the above problems, technicians in this field have conducted a lot of research. For example, CN105750469 discloses a forging die and forging method for disc forgings. The method is based on the right-left partitioning of the circular ring blank, and the right and left parts of the circular ring blank are formed successively; however, the method is not suitable for the precision forming of ultra-large and complex turbine disc structures. The reasons are: (1) The initial blank of the product involved in the method is a round cake, and the product is a solid structure rather than a circular ring structure. The die structure of the method is not suitable for solid structure products; (2) There are serious problems such as uneven deformation and uneven organization in the junction area where the left and right sides are formed successively.

[0004] Therefore, how to solve the problems of high forming load, large machining allowance and coarse grain mixed crystal caused by severe uneven deformation when forging ultra-large and complex structure turbine disks required for heavy gas turbines is an urgent issue to be solved by technical personnel in this field. Summary of the invention

[0005] In view of the above-mentioned deficiencies in the prior art, the object of the present invention is to provide a method for precision partitioning of ultra-large turbine disks. This method proposes a partitioning die forging method to address the problems of large forming load, large machining allowance and extremely low material utilization of ultra-large turbine disk forgings.

[0006] Furthermore, the present invention also provides a die for precision partitioning forming (pre-forging and final forging) of an ultra-large turbine disk.

[0007] In order to achieve the above object, the present invention adopts the following technical solution: A method for precision partitioned die forging of an ultra-large turbine disk forging comprises the following steps: The first step: the ultra-large turbine disk forging is designed to be divided into two areas: the center hub and spoke area and the outer spoke and rim area; the pre-forging mainly forms the center hub and spoke area, and the final forging mainly forms the outer spoke and rim area; Step 2: Based on the first step, design the pre-forging cavity, including the precision-formed center hub, spoke area, outer spoke, and rim area: 1) When designing the center hub area, the size should match the designed final forging; 2) When designing the center radial plate area, the height dimension of the center radial plate area is 10~40mm lower than the height dimension of the final forging, and the outer side height is 5~20mm lower than the inner side; 3) When designing the outer radial plate area, the height dimension at the top of the outer radial plate is 10~120mm higher than the height dimension of the final forging. At the same time, the mold cavity is provided with a positioning boss with a height of 10~30mm; 4) When designing the outer rim area, the height dimension at the top of the outer rim is 10~120mm higher than the height dimension of the final forging; Step 3: Based on the second step, design the final forging cavity, including the center hub, spoke area and outer spoke, rim area: 1) When designing the center hub area, the final forging cavity height should be 40~80mm higher than the pre-forging cavity to avoid contact between the final forging die and the center hub area; 2) When designing the center spoke area, the final forging cavity height should be 40~80mm higher than the pre-forging cavity to avoid contact between the final forging die and the center spoke area; 3) When designing the outer radial plate area, the dimensions of the outer radial plate should match the final forging; 4) When designing the outer rim area, the dimensions of the outer rim should match the final forging.

[0008] Furthermore, based on the above steps, through simulation, the cavity structure dimensions of the pre-forging die and the final forging die are optimized according to the filling and forming load conditions of the ultra-large turbine disk forgings; and the forming process of the ultra-large turbine disk forgings is simulated and analyzed to ensure that the forging forming load is less than 800MN.

[0009] Compared with the prior art, the present invention has the following beneficial effects: The present invention relates to a precision partitioned die forging forming method and die for ultra-large complex turbine disk forgings, which, combined with the analysis of numerical simulation results of the forging forming process, effectively solves the problems of large forming load, large machining allowance and extremely low material utilization rate of ultra-large turbine disk forgings.

[0010] (1) Under the existing 800MN press equipment conditions, the required billet and forging tonnage is reduced from the current 13.5 tons to 10 tons, saving 26% of materials, and each forging can save about 1.5 million yuan in material costs; (2) Save a lot of subsequent machining hours and increase efficiency by more than 50%; (3) Effectively increase the deformation of the difficult-to-deform area of ​​the forging and reduce the risk of producing coarse grains and mixed grains. BRIEF DESCRIPTION OF THE DRAWINGS

[0011] Figure 1 This is a schematic diagram (cross-sectional view) of the ultra-large turbine disk forging and part forming partitions of Example 1 of the present invention; Figure 2 for Figure 1 Schematic diagram of the pre-forging and final forging cavities of the super-large turbine disk; Figure 3 Schematic diagram of the forming area of ​​the super-large turbine disk pre-forging in Example 1, wherein 1 and 2 are the pre-forging main forming center hub and spoke plate areas; Figure 4 Schematic diagram of the forming area of ​​the super-large turbine disk pre-forging in Example 1, wherein 3' is the final forging area mainly forming the outer web and rim; Figure 5 This is a schematic diagram of the forming area of ​​the ultra-large turbine disk final forging in Example 1; Figure 6 (a) schematic diagram of die shape during final forging of a super-large turbine disk forging, (b) schematic diagram of simulation results of the final forging, and (c) equivalent strain diagram of the final forging in Example 1; Figure 7 It is a schematic diagram comparing the part drawing and the final forging in Example 1. DETAILED DESCRIPTION

[0012] The technical solution of the present invention is clearly and completely described below in conjunction with specific embodiments and drawings. Obviously, the embodiments are only representative of embodiments of the present invention and are not limited to the described embodiments. Therefore, the following detailed description of the embodiments provided in the drawings is not intended to limit the scope of the invention claimed for protection. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0013] It should be noted that similar numbers and letters represent similar items in the following figures, so once an item is defined in one figure, it does not need to be further defined and explained in subsequent figures. The terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inside", "outside", etc. indicate positions or positional relationships based on the positions or positional relationships shown in the figures, or the positions or positional relationships in which the invented product is usually placed when used. They are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present invention. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0014] Example 1 In view of the problems that the load of existing ultra-large turbine disk forgings during one-time die forging far exceeds 800MN, the machining allowance is large, and the material utilization rate is extremely low, this embodiment 1 proposes a pre-forging and final forging zone die forging method.

[0015] like Figure 1 As shown, the main body of the super-large turbine disk is in the shape of a disk, and the outer side of the central hub is sequentially composed of an annular central spoke plate area, a spoke plate, an outer spoke plate area and a rim.

[0016] See also Figure 2 , which is a schematic diagram of a specific mold cavity when the partition forging is adopted in Example 1 of the invention; wherein, line A is a machined part, line B is a pre-forging cavity, line C is a final forging cavity, and line D is a final forging.

[0017] The ultra-large turbine disk forging precision zoned die forging method of the present invention includes pre-forging and final forging steps, wherein the pre-forging mainly forms the center hub and the spoke plate area, and the final forging mainly forms the outer spoke plate and the rim area; the specific steps are: Step 1: Divide the forming design of the super-large turbine disk forging into two areas: the central hub and spoke area and the outer spoke and rim area; Step 2: Based on the first step, design the pre-forging cavity (see Figure 2 The B line in the figure includes the precision formed center hub, the spoke area and the outer spoke and rim area: 1) When designing the center hub area, the size should match the designed final forging; 2) When designing the center radial plate area, the height dimension of the center radial plate area is 10~40mm lower than the height dimension of the final forging, and the outer side height is 5~20mm lower than the inner side; 3) When designing the outer radial plate area, the height dimension at the top of the outer radial plate is 10~120mm higher than the height dimension of the final forging. At the same time, the mold cavity is provided with a positioning boss with a height of 10~30mm; 4) When designing the outer rim area, the height dimension at the top of the outer rim is 10~120mm higher than the height dimension of the final forging; Step 3: Based on the second step, design the final forging cavity (see Figure 2 The C line in the figure includes the center hub, the spoke area, the outer spoke and the rim area: 1) When designing the center hub area, the final forging cavity height should be 40~80mm higher than the pre-forging cavity to avoid contact between the final forging die and the center hub area; 2) When designing the center spoke area, the final forging cavity height should be 40~80mm higher than the pre-forging cavity to avoid contact between the final forging die and the center spoke area; 3) When designing the outer radial plate area, the dimensions of the outer radial plate should match the final forging; 4) When designing the outer rim area, the dimensions of the outer rim should match the final forging.

[0018] Furthermore, based on the above steps, through simulation, the cavity structure dimensions of the pre-forging die and the final forging die are optimized according to the filling and forming load conditions of the ultra-large turbine disk forgings, and the forming process of the ultra-large turbine disk forgings is simulated and analyzed to ensure that the forging forming load is less than 800MN.

[0019] See also Figure 3 The figure shows the schematic diagram of the forming area of ​​the ultra-large turbine disk preforging of Example 1. The diameter of the ultra-large turbine disk is 2.3 meters, and the billet weighs 13.5 tons. The size of the hub area 1 in the preforging cavity matches the designed final forging; the height dimension of the central spoke area 2 is 10~40mm lower than the height dimension of the final forging, and the height of the outer side is 5~20mm lower than that of the inner side; the height dimension at the top 3 of the outer spoke is 10~120mm higher than the height dimension of the final forging. At the same time, the mold cavity is provided with a positioning boss 5 with a height of 10~30mm; the height dimension at the top 4 of the outer rim is 10~120mm higher than the height dimension of the final forging.

[0020] Figure 4 (a) is a schematic diagram of the die shape during the pre-forging of the super-large turbine disk forging of the invention. The pre-forging process is numerically simulated, and the pre-forged part after forming is as follows Figure 4 (b) shown.

[0021] Figure 5 This is a schematic diagram of the forming area of ​​the final forging of the super-large turbine disk of the invention. The height dimension of the center hub area 1' of the final forging cavity is 40~80mm higher than that of the pre-forging cavity, so as to avoid the final forging die from contacting the center hub area; the height dimension of the center spoke area 2' of the final forging cavity is 40~80mm higher than that of the pre-forging cavity, so as to avoid the final forging die from contacting the center spoke area; the dimensions of the outer spoke area and the wheel rim 3' match those of the final forging.

[0022] Figure 6 (a) is a schematic diagram of the die shape during the final forging of the super-large turbine disk forging of the invention. The final forging process is numerically simulated, and the final forging after forming is as follows Figure 6 (b). Figure 6 (c) The equivalent strain diagram of the final forging shows that the deformation uniformity of the forging is effectively improved.

[0023] like Figure 7 The final forging drawing and part drawing of the super-large turbine disc of the invention object are shown in the figure. It can be seen that the method of the present invention can process parts that meet the size requirements within the equipment capacity. It has been verified that under the existing 800MN press equipment conditions, the required billet and forging tonnage is reduced from the current 13.5 tons to 10 tons, saving 26% of materials, and each forging can save about 1.5 million yuan in material costs. A large amount of subsequent machining hours are saved, and the efficiency is improved by more than 50%.

[0024] In summary, the present invention designs a zoned forging process to address the problems of high forming load and large machining allowance during traditional forging of ultra-large turbine disk forgings. The method of the present invention can process parts that meet size requirements within the capacity of the equipment.

[0025] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A method for precision partitioned die forging of ultra-large turbine disk forgings, characterized in that: The following steps are involved: Step 1: Divide the forming design of the super-large turbine disk forging into two areas: the central hub spoke area and the outer spoke rim area. The pre-forging mainly forms the central hub spoke area, and the final forging mainly forms the outer spoke rim area. Step 2: Based on the first step, design the pre-forging cavity, including the precision-formed center hub, spoke area, outer spoke, and rim area: 1) When designing the center hub area, the size should match the designed final forging; 2) When designing the center radial plate area, the height dimension of the center radial plate area is 10~40mm lower than the height dimension of the final forging, and the outer side height is 5~20mm lower than the inner side; 3) When designing the outer radial plate area, the height dimension at the top of the outer radial plate is 10~120mm higher than the height dimension of the final forging. At the same time, the mold cavity is provided with a positioning boss with a height of 10~30mm; 4) When designing the outer rim area, the height dimension at the top of the outer rim is 10~120mm higher than the height dimension of the final forging; Step 3: Based on the second step, design the final forging cavity, including the center hub, spoke area and outer spoke, rim area: 1) When designing the center hub area, the final forging cavity height should be 40~80mm higher than the pre-forging cavity to avoid contact between the final forging die and the center hub area; 2) When designing the center spoke area, the final forging cavity height should be 40~80mm higher than the pre-forging cavity to avoid contact between the final forging die and the center spoke area; 3) When designing the outer radial plate area, the dimensions of the outer radial plate should match the final forging; 4) When designing the outer rim area, the dimensions of the outer rim should match the final forging.

2. According to the method for precision zoning forming of ultra-large turbine disk forgings in claim 1, the basic feature is that it also includes simulation to adjust the shape and size of the pre-forging die and the final forging die according to the filling and forming load conditions of the ultra-large turbine disk forgings.

3. According to claim 1, the method for precision partitioning of ultra-large turbine disk forgings is characterized in that the forming process of the ultra-large turbine disk forgings is simulated and analyzed to ensure that the forging forming load is less than 800MN.

4. The method for precision partitioning of ultra-large turbine disk forgings according to any one of claims 1 to 3, characterized in that: The ultra-large turbine disk forging is an ultra-large turbine disk with a diameter greater than 1.9 meters and a blank weight of 10 tons.

5. A precision partitioning die for ultra-large turbine disc forgings, characterized in that: The method is adopted to manufacture the pre-forging and final forging dies.

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