Manufacturing method of power turbine case special-shaped ring forge piece for gas turbine

Abstract

The invention relates to the technical field of turbine case machining, in particular to a manufacturing method of a power turbine case special-shaped ring forge piece for a gas turbine, which comprises the following steps: S1, carrying out upsetting, punching, horse rod reaming and primary blank manufacturing treatment on a forge piece blank by adopting free forging; s2, carrying out secondary blank manufacturing treatment on the forging blank by adopting a forming die forging forming process; and S3, a special-shaped ring rolling technology is adopted for rolling the prefabricated blank, the process size needed by the forge piece is achieved, according to the manufacturing method, the blank is subjected to upsetting, punching, horse rod chambering blank manufacturing, tire mold forging blank manufacturing and special-shaped ring rolling forming, and finally the forge piece product is obtained. According to the special-shaped ring forge piece of the power turbine case manufactured through the manufacturing method, the cost is reduced, the efficiency is improved, and good economic benefits are brought to companies.

Description

Technical Field

[0001] The invention relates to the technical field of turbine casing processing, and in particular to a method for manufacturing a special-shaped ring forging of a power turbine casing for a gas turbine. Background Art

[0002] Gas turbines are known as the jewel in the crown of the equipment manufacturing industry. Gas turbines are the leading technology of the 21st century. China's gas turbine market is now on a growth trend and continues to grow under the impetus of the development of the power and energy industry and environmental protection. The rapid technological progress of gas turbines and the increasing attention to distributed power generation technology are driving the growth of China's gas turbine industry. Turbine casing parts are one of the most difficult parts to manufacture in gas turbines. The main function of the casing is to support and protect internal rotating parts, such as the wheel, rotor, blades, etc.

[0003] The structure of the casing is very complex. At present, the commonly used method in the production of special-shaped ring forgings is free forging, but this manufacturing method is costly and inefficient. Summary of the invention

[0004] In order to solve the above technical problems, an embodiment of the present invention provides a method for manufacturing a power turbine casing special-shaped ring forging for a gas turbine, so as to reduce the cost of manufacturing the power turbine casing special-shaped ring forging and improve the efficiency of manufacturing the power turbine casing special-shaped ring forging.

[0005] The present invention is achieved through the following technical solutions:

[0006] A method for manufacturing a special-shaped ring forging of a power turbine casing for a gas turbine comprises the following steps:

[0007] S1: Free forging is used to make the forging blank for the first time;

[0008] S2: The forging blank is subjected to a second blanking process by using a membrane forging process;

[0009] S3: The prefabricated blank is rolled using the special-shaped ring rolling technology.

[0010] Further preferably, the first blank making process in S1 is to make the blank into a truncated cone with a large head end and a small head end, and after heating, it is sequentially roughened, punched and expanded with a rod.

[0011] More preferably, the heating temperature of the blank is 1160° C., and after the blank is kept warm and heated thoroughly, it is roughened and punched on a 5000-ton hydraulic press.

[0012] Further preferably, the punching is single-sided punching, with the large end of the punch facing downward, and punching starts from the small end of the blank.

[0013] Further preferably, the method of expanding the hole with the horse stick is: lift one end of the horse stick so that the center line of the horse stick has an angle of 3-7 degrees in the horizontal direction, and then put the punched blank into the middle of the horse stick to expand the hole. When expanding the hole, start extrusion from the big end of the blank, and the amount of pressure each hammer presses is 10-20mm. The heating temperature of the horse stick expansion is 1160℃.

[0014] Further preferably, the second blank making method in S2 is: making an outer die and a forming punch, the height of the outer die is 15-20 mm higher than the designed forming forging size, heating the first made blank to 1160°C, putting it into the outer die after keeping it warm, and then aligning the forming punch and putting it into the blank, roughing it on a 5000-ton hydraulic press, and extruding it. Before extrusion, the outer die and the forming punch are brushed with heat-resistant lubricant.

[0015] Further preferably, the method for rolling the prefabricated blank in S3 is: heating the second prefabricated blank to 1160°C, keeping it warm and then rolling it into shape in two stages on a 4500M horizontal ring rolling machine.

[0016] Further preferably, the ring rolling forming method is divided into two fires: the deformation amount in each fire is more than 18%, the main roller speed of the ring rolling machine is 0.8-1rad / s, and the feed amount of the core roller is 0.6-0.8mm / s.

[0017] Further preferably, the manufacturing method also includes designing and optimizing the forging blank drawing before S1, using numerical simulation technology to simulate the rolling forming of the forging, and optimizing the size structure and simulation parameters of the preform.

[0018] Beneficial effects of the present invention:

[0019] The present invention successfully realizes the design of power turbine casing special-shaped ring forgings, and each product saves about 1500kg of raw materials compared with free forging, and the machining time is reduced by two working days on average; excluding the tooling and die fees, each product saves about 35,000 yuan in economic value; about 20 pieces of this product are produced each year, which reduces costs and improves efficiency, bringing good economic benefits to the company.

[0020] The specific implementation modes of the present invention are further described in detail below in conjunction with the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] The accompanying drawings are used to provide a further understanding of the present invention and constitute a part of the specification. Together with the following specific embodiments, they are used to explain the present invention but do not constitute a limitation of the present invention. In the accompanying drawings:

[0022] Figure 1 The present invention is a schematic structural diagram of a special-shaped ring forging of a power turbine casing for a gas turbine.

[0023] Figure 2 A schematic diagram of roughening of a blank during the first blank making process in the manufacturing method of the present invention.

[0024] Figure 3 A schematic diagram of blank punching during the first blank making process in the manufacturing method of the present invention.

[0025] Figure 4 A schematic diagram of the hole expansion of the horse rod during the first blank making in the manufacturing method of the present invention.

[0026] Figure 5 Schematic diagram of the second blanking die forging in the manufacturing method of the present invention.

[0027] Figure 6 Schematic diagram of the special-shaped cerclage forming in the manufacturing method of the present invention.

[0028] 1-blank, 2-big head end, 3-small head end, 4-upper hammer, 5-lower hammer, 6-leakage plate, 7-punch, 8-horse rod, 9-outer die, 10-forming punch, 11-core roller sleeve, 12-core roller, 13-main roller, 14-upper plate cover, 15-lower plate cover, 16-forging. DETAILED DESCRIPTION

[0029] The embodiments of the present invention are described in detail below, examples of which are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present invention, and cannot be understood as limiting the present invention.

[0030] In the description of the present invention, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise" and the like indicate positions or positional relationships based on the positions or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying 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 limiting the present invention. In addition, the terms "first" and "second" are only used for descriptive purposes, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Therefore, the features defined as "first" and "second" may explicitly or implicitly include one or more of the features. In the description of the present invention, the meaning of "multiple" is two or more, unless otherwise clearly and specifically defined.

[0031] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection, an electrical connection, or mutual communication; it can be a direct connection, or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0032] In the present invention, unless otherwise clearly specified and limited, a first feature being "above" or "below" a second feature may include that the first and second features are in direct contact, or may include that the first and second features are not in direct contact but are in contact through another feature between them. Moreover, a first feature being "above", "above" and "above" a second feature includes that the first feature is directly above and obliquely above the second feature, or simply indicates that the first feature is higher in level than the second feature. A first feature being "below", "below" and "below" a second feature includes that the first feature is directly below and obliquely below the second feature, or simply indicates that the first feature is lower in level than the second feature.

[0033] In addition, the present invention provides examples of various specific processes and materials, but a person skilled in the art may recognize the application of other processes and / or the use of other materials.

[0034] Please refer to Figure 1-6 A method for manufacturing a special-shaped ring forging of a power turbine casing for a gas turbine mainly comprises the following steps:

[0035] 1. Design the forging blank drawing according to the finished part drawing, see Figure 1 .

[0036] 2. Use numerical simulation technology on Deform software to simulate the ring rolling of the forging blank, and optimize the design of the forging blank based on the simulation results.

[0037] 3. Use free forging to roughen, punch and expand the blank, and do the first blanking process for the forging blank. Figure 2 , Figure 3 and Figure 4 .

[0038] 4. Design the outer mold, punch and other tools required for tire die forging, and use the tire membrane forging process to make the forging blank for the second time. Figure 5 .

[0039] 5. Through the design of the main roller mold, core roller, core roller sleeve, etc. of the horizontal ring rolling machine, the prefabricated blank is rolled using the special-shaped ring rolling technology to achieve the process size required for the forging, see Figure 6 .

[0040] In summary, the manufacturing process of the power turbine casing special-shaped ring forging is as follows: the blank is subjected to upsetting - punching - reaming by a bar - forging by a membrane - special-shaped ring rolling to form, and finally a forging product is obtained.

[0041] A method for manufacturing a special-shaped ring forging of a power turbine casing for a gas turbine, the specific method is as follows:

[0042] 1) Design of forging blank drawing of product

[0043] The design principle first considers the rationality of the product structure, because the product size is large, the structure shape is complex, the product wall thickness is uneven, etc. Therefore, when designing the blank size, the fluidity of the metal during forming should be considered.

[0044] Secondly, the uniformity of the distribution of the mechanical properties of the product should be considered. Due to the uneven wall thickness of the finished product, if the design of the forging 16 margin is unreasonable, the overall structure of the forging 16 will be unevenly distributed, resulting in uneven deformation during hot working.

[0045] Finally, the economic efficiency of the product must be considered. Because the casing material is 1Cr12Ni2MoWVNbN, which is a martensitic heat-resistant stainless steel, the raw material price is relatively expensive. The processing allowance of forging 16 is too large, which leads to material waste and increases machining time and processing costs. Combined with the rolling accuracy of the ring rolling machine and the operating level of the workers, a reasonable forging 16 blank drawing is designed. Figure 1 .

[0046] 2) Using numerical simulation technology, simulate the rolling forming of forging 16 in Deform software

[0047] Since the structure of the forging 16 is relatively complex, it cannot be directly rolled into a ring. A preform needs to be made. The size of the preform can be roughly designed based on experience to facilitate input into the computer for simulation. The model after simulation is analyzed from macro to micro, and the size structure and simulation parameters of the preform are reasonably optimized. During the simulation, the speed of the main roller 13 is controlled at 1rad / s, the feed rate of the core roller 12 is controlled at 0.8mm / s, and the ring rolling temperature is selected at 1160℃. After a series of experiments, satisfactory simulation results are obtained.

[0048] 3) Design of preform size.

[0049] The purpose of designing the blank is to distribute the structure of the blank 1 more reasonably so that the metal can flow more smoothly to the required position during the forming process.

[0050] 4) First batching

[0051] For the first blank making, we chose to make the blank 1 into a cylindrical shape with tapered large and small ends, that is, similar to a truncated cone, with a large end 2 and a small end 3. The heating temperature of the blank 1 was selected to be 1160℃. After the blank 1 was heated thoroughly, it was roughened and punched on a 5000-ton hydraulic press, and then the hole was expanded by a horse rod. Figure 2-4 .

[0052] It is worth noting that when the blank 1 is roughened at the front, it should be made into a shape with a slight taper, such as Figure 2 When roughing, place the blank 1 between the upper hammer 4 and the lower hammer 5, and then choose single-sided punching when punching, such as Figure 3 The blank 1 is placed on the drain plate 6, with the big end of the punch 7 facing downward, and punching starts from the small end 3 of the blank 1. In this way, the blank 1 obtained after punching the hole will naturally present a clear big and small head shape.

[0053] like Figure 4 When expanding the hole of the horse rod 8, we choose to raise one end of the horse rod 8 so that the center line of the horse rod 8 has an angle of about 5 degrees in the horizontal direction, such as 3-7 degrees, and then put the punched blank 1 into the middle of the horse rod 8 to expand the hole. When expanding the hole, start extrusion from the big end 2 of the blank 1, and control the amount of each hammer to be about 10-20mm. The heating temperature for expanding the hole of the horse rod 8 is still selected at 1160℃. After the blank 1 is heated through, it is carried out on a 5000-ton hydraulic press.

[0054] 5) Second blanking

[0055] When making the second blank, we chose to use the method of forging the blank with the tire membrane. The tooling produced includes an outer die 9 and a forming punch 10. The blank 1 made for the first time is heated to 1160℃, kept warm and then put into the outer die 9, and then the forming punch 10 is placed in the blank 1, and then roughened and extruded in a 5000-ton hydraulic press. Before extrusion, the outer die 9 and the forming punch 10 should be coated with heat-resistant lubricant, such as Figure 5 .

[0056] It is worth noting that the outer die 9 must be sufficiently dimensioned in height when it is designed, at least 15-20 mm more, so that the size of the obtained billet is higher than the size of the forging during forming. Because in the final rolling process, due to the relatively thick effective cross section of the forging 16, grooves are easily generated on the end face during the deformation process, so sufficient height must be reserved to avoid the generation of grooves.

[0057] 6) Rolling forming

[0058] The second prefabricated blank 1 is heated to 1160℃, kept warm and then rolled into shape in two stages on a 4500M horizontal ring rolling machine. Figure 6 , the core roller sleeve 11 designed in advance needs to be installed on the core roller 12, and the main roller 13, upper plate cover 14 and lower plate cover 15 need to be installed and debugged in place. Before rolling the ring, all the main rollers 13, core rollers 12, cone rollers, etc. need to be preheated to about 200℃.

[0059] The ring rolling is formed in two fires, and the deformation of each fire is controlled to be above 18%. The speed of the main roller 13 of the ring rolling machine is controlled at 0.8-1rad / s, and the feed rate of the core roller is controlled at 0.6-0.8mm / s. After the rolling is completed, the red-measured size is immediately transferred to the annealing furnace for furnace cooling and annealing.

[0060] In the description of this specification, the description with reference to the terms "one embodiment", "certain embodiments", "illustrative embodiments", "examples", "specific examples", or "some examples" means that the specific features, structures, materials, or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representation of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials, or characteristics described may be combined in any one or more embodiments or examples in a suitable manner.

[0061] In summary, although the present invention has been disclosed as above in terms of preferred embodiments, the above preferred embodiments are not intended to limit the present invention. A person skilled in the art may make various changes and modifications without departing from the spirit and scope of the present invention. Therefore, the scope of protection of the present invention shall be based on the scope defined in the claims.

Claims

1. A method for manufacturing a special-shaped ring forging of a power turbine casing for a gas turbine, characterized in that: The following steps are involved: S1: Free forging is used to make the forging blank for the first time; S2: The forging blank is subjected to a second blanking process by using a membrane forging process; S3: The prefabricated blank is rolled using the special-shaped ring rolling technology.

2. The method for manufacturing a gas turbine power turbine casing profiled ring forging according to claim 1, characterized in that: The first blank making process in S1 is to make the blank into a truncated cone with a large head end and a small head end, and then perform roughening, punching and hole expansion with a rod in sequence after heating.

3. The method for manufacturing a special-shaped ring forging of a power turbine casing for a gas turbine according to claim 2, characterized in that: The heating temperature of the blank is 1160℃. After the blank is kept warm and heated thoroughly, it is roughened and punched on a 5000-ton hydraulic press.

4. The method for manufacturing a gas turbine casing profile ring forging according to claim 2, characterized in that: The punching is single-sided, with the large end of the punch facing downward and starting from the small end of the blank.

5. The method for manufacturing a gas turbine casing special-shaped ring forging according to claim 2, characterized in that: The method of expanding the hole with a horse stick is as follows: lift one end of the horse stick so that the center line of the horse stick has an angle of 3-7 degrees in the horizontal direction, and then put the punched blank into the middle of the horse stick to expand the hole. When expanding the hole, start extruding from the big end of the blank. The amount of pressure each time the hammer presses is 10-20mm. The heating temperature for expanding the hole with the horse stick is 1160℃.

6. The method for manufacturing a special-shaped ring forging of a power turbine casing for a gas turbine according to claim 1, characterized in that: The second blank making method in S2 is: make an outer die and a forming punch, the height of the outer die is 15-20mm higher than the designed forming forging size, heat the first blank to 1160℃, put it into the outer die after keeping it warm, and then put the forming punch into the blank in the center, and roughen and extrude it on a 5000-ton hydraulic press. Before extrusion, the outer die and the forming punch are brushed with heat-resistant lubricant.

7. The method for manufacturing a special-shaped ring forging of a power turbine casing for a gas turbine according to claim 1, characterized in that: The method for rolling the prefabricated blank in S3 is: heating the second prefabricated blank to 1160°C, keeping it warm and then rolling it into shape in two stages on a 4500M horizontal ring rolling machine.

8. The method for manufacturing a special-shaped ring forging of a power turbine casing for a gas turbine according to claim 7, characterized in that: The ring rolling forming method is divided into two fires: the deformation amount of each fire is more than 18%, the main roller speed of the ring rolling machine is 0.8-1rad / s, and the feed amount of the core roller is 0.6-0.8mm / s.

9. The method for manufacturing a special-shaped ring forging of a power turbine casing for a gas turbine according to claim 1, characterized in that: The manufacturing method also includes designing and optimizing the forging blank drawing before S1, using numerical simulation technology to simulate the rolling forming of the forging, and optimizing the size structure and simulation parameters of the preform.

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