Stainless steel valve shell forging method and stainless steel valve shell forge piece
Patent Information
- Application Number
- CN202510206475.4
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-02-25
- Publication Date
- 2025-05-23
Smart Images
Figure CN120023278A_ABST
Abstract
Description
Technical Field
[0001] The present application relates to the field of aircraft parts forging, and in particular to a stainless steel valve housing forging method and a stainless steel valve housing forging. Background Art
[0002] Stainless steel is usually used for forging valve (or valve) housings. There are many types of valves on aircraft, including high-pressure valves, anti-icing valves, etc. These valves all contain housings as their key components.
[0003] However, the shape of the valve housing forgings on the aircraft is relatively complex, and there are steps and excessive rounded corners in the forging die cavity, which causes reverse flow and intersection of material flow during forging, resulting in folding defects in the forgings.
[0004] Therefore, in order to improve the product quality of forgings, how to optimize the folding defects of stainless steel valve housing forgings has become our need. Summary of the invention
[0005] The present application provides a stainless steel valve housing forging method and a stainless steel valve housing forging, which are used to solve the problem of folding defects of the stainless steel valve housing forging.
[0006] In a first aspect, the present application provides a method for forging a stainless steel valve housing, the method comprising: heating a stainless steel blank to a required temperature for single-fire die pressing, and upsetting the stainless steel blank; single-fire die pressing comprises three steps of upsetting, flattening, and forming; flattening the upset stainless steel blank to a preset height range; the lower limit of the preset height range is a basic height in the process requirements of the flattening step; the upper limit of the preset height range is less than or equal to the sum of the basic height and the upper tolerance in the process requirements of the flattening step; and die pressing the flattened stainless steel blank to obtain a stainless steel valve housing forging.
[0007] It should be understood that based on the process of analyzing the causes of folding defects, it can be seen that the reason for the folding defects in forgings is that the flattening height of the billet is too small. When the flattening height of the billet is too small, the metal flows in the vertical and horizontal directions of the mold cavity are not synchronized. When the metal flows horizontally to the burr bridge, the vertical direction of the cavity is not yet full. Under the action of the resistance of the burr bridge, the horizontal metal flows back and intersects with the vertical metal, resulting in folds on the surface of the forging.
[0008] The stainless steel valve housing forging method provided in the present application can flatten the stainless steel blank after upsetting to a preset height range, and the lower limit of the preset height range is the basic height in the flattening process requirements, and the upper limit of the preset height range is less than or equal to the sum of the basic height and the upper tolerance in the flattening process requirements. That is, when the present application performs the flattening process, the flattened height generally belongs to the higher part of the height in the process requirements, thereby avoiding folding defects when the stainless steel valve housing forging is pressed during die pressing.
[0009] Optionally, flattening the upset stainless steel blank to a preset height range includes: flattening the upset stainless steel blank to a preset height range using a clamp; arranging a height limiting block between the clamps; and the height of the height limiting block is the same as the basic height.
[0010] Optionally, the height limiting block is detachably fixed to the fixture.
[0011] Optionally, the upset stainless steel blank is flattened to a preset height range using a clamp, including: flattening the upset stainless steel blank using a clamp; measuring the height of the flattened stainless steel blank; when the height of the stainless steel blank is higher than an upper limit of the preset height range, repeatedly flattening the stainless steel blank until the height of the stainless steel blank is within the preset height range.
[0012] Optionally, the basic height in the flattening step process requirements is 30mm, the upper tolerance in the flattening step process requirements is 2mm, and the lower tolerance in the flattening step process requirements is -2mm; the lower limit of the preset height range is 30mm, and the upper limit of the preset height range is 32mm.
[0013] Optionally, the stainless steel blank is 1Cr11Ni2W2MoV.
[0014] Optionally, the method also includes: determining multiple candidate heights according to the basic height, upper tolerance, and lower tolerance in the flattening step process requirements; performing numerical simulation on the forming step when the stainless steel billet after upsetting is flattened to multiple candidate heights to obtain simulation results corresponding to each of the multiple candidate heights; and determining a preset height range according to the simulation results corresponding to each of the multiple candidate heights.
[0015] Optionally, the method further comprises: using a magnifying glass to check whether the stainless steel valve housing forging has folding defects.
[0016] Optionally, the method further comprises: performing fluorescent flaw detection on the stainless steel valve housing forging.
[0017] In a second aspect, the present application provides a stainless steel valve housing forging, which is forged using the stainless steel valve housing forging method described in the first aspect.
[0018] The beneficial effects of the second aspect mentioned above can be referred to the first aspect and will not be elaborated on again. BRIEF DESCRIPTION OF THE DRAWINGS
[0019] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.
[0020] Figure 1 Schematic diagram of folding defects; Figure 2 A schematic diagram of the molding process of the valve housing provided in the embodiment of the present application; Figure 3 A simulation diagram of forging die forming provided in an embodiment of the present application; Figure 4 A schematic diagram of the flattening process provided in an embodiment of the present application; Figure 5 A simulation result diagram of the blank flattening height provided in the embodiment of the present application when it is 28 mm; Figure 6 A simulation result diagram of the blank flattening height provided in the embodiment of the present application when it is 29 mm; Figure 7 A simulation result diagram of the blank flattening height of 30 mm provided in the embodiment of the present application; Figure 8 A physical picture of a reproduction test when the flattening height of the blank provided in the embodiment of the present application is 28 mm; Fig. 9 A physical picture of a reproduction test when the flattening height of the blank provided in the embodiment of the present application is 29 mm; Fig.10 A physical picture of a reproduction test when the flattening height of the blank provided in the embodiment of the present application is 30 mm; Fig.11 A physical picture of a reproduction test when the flattening height of the blank provided in the embodiment of the present application is 31 mm; Fig.12 A physical picture of a reproduction test when the flattening height of the blank provided in the embodiment of the present application is 32 mm; Fig.13 A schematic diagram of the process of forging a stainless steel valve housing provided in an embodiment of the present application; Fig.14 A schematic diagram of the flattening process using a height-limiting block provided in an embodiment of the present application. DETAILED DESCRIPTION
[0021] The following will be combined with the drawings in the embodiments of the present application to clearly and completely describe the technical solutions in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.
[0022] It should be noted that, in the embodiments of the present application, words such as "exemplarily" or "for example" are used to indicate examples, illustrations or descriptions. Any embodiment or design described as "exemplarily" or "for example" in the embodiments of the present application should not be interpreted as being more preferred or more advantageous than other embodiments or designs. Specifically, the use of words such as "exemplarily" or "for example" is intended to present related concepts in a specific way.
[0023] In order to facilitate the clear description of the technical solutions of the embodiments of the present application, in the embodiments of the present application, the words "first", "second", etc. are used to distinguish the same items or similar items with basically the same functions and effects. Those skilled in the art can understand that the words "first", "second", etc. are not limiting the quantity and execution order.
[0024] 1Cr11Ni2W2MoV is a 12% chromium martensitic heat-resistant stainless steel with high room temperature strength and endurance strength, good toughness and oxidation resistance, good corrosion resistance in fresh water and humid air, and is suitable for load-bearing components (such as valve housings) working under forging temperatures below 550°C and humid conditions. For example, valves can be various types of valves on aircraft, including high-pressure valves, anti-icing valves, etc., all of which contain housings as their key components.
[0025] The significant unevenness of local incremental deformation during die forging makes it easy for folding defects to occur at the inner fillets, sharp corners, and places with large interface changes in the forging. In addition, the shape of the valve housing forging is relatively complex, and there are steps and excessive fillets in the forging die cavity, which causes counterflow and intersection of material flow during forging, and is also prone to folding defects in the forging.
[0026] For example, Figure 1 This is a schematic diagram of a folding defect. Figure 1 , Figure 1 The image in the figure shows the step return material folding of the stainless steel valve housing after grinding, repairing and trimming.
[0027] Therefore, in order to improve the product quality of forgings, how to optimize the folding defects of stainless steel valve housing forgings has become our need.
[0028] First, the causes of folding defects are analyzed.
[0029] The valve housing forgings were sampled along the defective parts for analysis. The results showed that the defect was straight and arc-shaped, and the defect surface was gray-black. On the ground metallographic section, the linear defect was at a certain angle to the surface. Oxide scale morphology was visible on both sides of the defect, and the conformity was poor. After corrosion, no abnormal organization was found near the defect. Based on the metallographic organization of the defect, it was determined that the defect was a folding defect generated during forging.
[0030] For example, Figure 2 Schematic diagram of the molding process of the valve housing provided in the embodiment of the present application. Figure 2 As shown, the valve housing forging is formed by one-fire die pressing, and the one-fire die pressing forming is divided into three steps: upsetting, flattening, and forming.
[0031] The forming step is to make the size of the blank after die forming meet the requirements of the forging drawing. In this process, the metal flows under the constraints of the mold cavity.
[0032] For example, Figure 3 This is a simulation diagram of the die forming of a forging provided in the embodiment of the present application. Figure 3 As shown in the figure, if the metal flows in the vertical and horizontal directions of the mold cavity asynchronously, that is, when the metal flows horizontally to the burr bridge, the vertical direction of the cavity is not yet full. Under the action of the resistance of the burr bridge, the horizontal metal B flows back and intersects with the vertical metal A, forming a fold on the surface of the forging at this part ( Figure 3 The circled area is shown as an example).
[0033] According to the simulated metal flow analysis, the flow speed and amount of metal B in the horizontal direction and metal A in the vertical direction are related to the flattening height of the billet.
[0034] For example, Figure 4 This is a schematic diagram of the flattening process provided in the embodiment of the present application. Figure 4 As shown, the bar needs to be placed flat on the fixture platform during flattening, and the flattening height is affected by the pressure of the equipment, and the flattening height of the blank fluctuates within the process requirements.
[0035] For example, the flattening height required by the flattening process step may be specifically 30 mm ± 2 mm, that is, the flattening height of the blank fluctuates within the process requirement of 28 mm-32 mm.
[0036] In order to verify the relationship between the die folding defect and the flattening height of the blank, a numerical simulation analysis can be performed on the forming process of the valve housing forging. The flattening heights H=28mm (process difference), H=29mm, and H=30mm (process nominal value, or basic height) are selected for die forming simulation analysis.
[0037] For example, Figure 5 This is a simulation result diagram of the blank flattening height provided in the embodiment of the present application when it is 28 mm. Figure 5 As shown in the figure, when the flattening height of the blank is 28 mm, folding defects occur in the forging after die pressing.
[0038] For example, Figure 6 This is a simulation result diagram of the blank flattening height provided in the embodiment of the present application when it is 29 mm. Figure 6 As shown in the figure, when the flattening height of the billet is 29 mm, the flow of the metal in the die cavity is basically synchronous, and the cavity is finally filled, and a slight folding defect appears in the forging.
[0039] For example, Figure 7 This is a simulation result diagram of the blank flattening height of 30 mm provided in the embodiment of the present application. Figure 7 As shown in the figure, when the billet flattening height is 30 mm, the billet flattening height is basically consistent with the thickness of the forging, the metal filling in the mold cavity and the filling in the bin are carried out simultaneously, and the forging will not produce folding defects.
[0040] In order to verify the die-pressing simulation results of different flattening heights, a reproduction test of folding defects was carried out on the valve housing forging. Five billets were selected as test pieces, and the test pieces were die-formed with one fire at H=28mm (lower process difference), H=29mm, H=30mm, H=31mm, and H=32mm (upper process difference).
[0041] For example, Figure 8 This is a real picture of the reproduction test when the flattening height of the blank provided in the embodiment of the present application is 28mm. Figure 8 As shown in the figure, when the blank is flattened to 28 mm and then formed, the stainless steel valve housing forging is folded ( Figure 8 The circled area is shown as an example).
[0042] For example, Fig. 9 This is a real picture of the reproduction test when the flattening height of the blank provided in the embodiment of the present application is 29mm. Fig. 9 As shown in the figure, when the blank is flattened to 29 mm and then formed, the stainless steel valve housing forging is slightly folded ( Fig. 9 The circled area is shown as an example).
[0043] For example, Fig.10 This is a real picture of the reproduction test when the flattening height of the blank provided in the embodiment of the present application is 30mm. Fig.10 As shown, when the billet is flattened to 30 mm and then formed, the obtained stainless steel valve housing forging has no folding.
[0044] For example, Fig.11This is a real picture of the reproduction test when the flattening height of the blank provided in the embodiment of the present application is 31mm. Fig.11 As shown, when the billet is flattened to 31 mm and then formed, the obtained stainless steel valve housing forging has no folding.
[0045] For example, Fig.12 This is a real picture of the reproduction test when the blank flattening height is 32mm provided in the embodiment of the present application. Fig.12 As shown, when the billet is flattened to 32 mm and then formed, the obtained stainless steel valve housing forging has no folding.
[0046] from Figures 8 to 12 It can be seen from the actual picture of the reproduction test that with the increase of the flattening height, the folding defect gradually decreases and disappears. When the flattening height H=30mm, 31mm, and 32mm, the stainless steel valve shell forging has no folding defect, that is, when H≥30mm, the folding defect can be better controlled.
[0047] Based on the understanding of the above embodiments, Fig.13 The following is a schematic diagram of a process for forging a stainless steel valve housing provided in an embodiment of the present application. Fig.13 As shown, the method includes the following steps: S101, heating the stainless steel blank to a required temperature for first-stage die forming, and upsetting the stainless steel blank.
[0048] The required temperature may be 1150°C-850°C. For example, the required temperature may be 1150°C, 1100°C, 1050°C, 1000°C, 950°C, 900°C, or 850°C. The embodiment of the present application does not limit the specific value of the required temperature. The first-stage die forming includes three steps: upsetting, flattening, and forming. For details, please refer to the above Figure 2 As shown, no further description is given here.
[0049] Alternatively, the stainless steel blank may be 1Cr11Ni2W2MoV.
[0050] S102, flattening the stainless steel billet to a preset height range.
[0051] Among them, the lower limit of the preset height range is the basic height in the process requirements of the flattening step; the upper limit of the preset height range is less than or equal to the sum of the basic height and the upper tolerance in the process requirements of the flattening step.
[0052] Optionally, as described above, the flattening height required by the flattening process step may be specifically 30 millimeters (mm) ± 2 mm. In this case, the preset height interval may be specifically [30 mm, 32 mm].
[0053] Optionally, as described above, the stainless steel fatigue may be flattened by using a fixture. In this case, the above S102 may specifically include: using a fixture to flatten the stainless steel blank after upsetting to a preset height range.
[0054] Among them, a limited height block is set between the clamps, and the height of the limited height block is the same as the basic height required by the flattening process step.
[0055] Optionally, the height limiting block is detachably fixed to the fixture.
[0056] For example, Fig.14 This is a schematic diagram of the flattening process using a height-limiting block provided in the embodiment of the present application. Fig.14 As shown, the height of the height limit block is 30 mm. The 30 mm height limit block can be used to control the flattening height of the stainless steel billet according to H = 30 mm-32 mm.
[0057] Optionally, in the case of using a height limiting block, the step of flattening the upset stainless steel blank to a preset height range by using a clamp may specifically include the following steps: Step 1a: Flatten the stainless steel blank after upsetting using a clamp.
[0058] Step 2a, measuring the height of the flattened stainless steel billet.
[0059] Step 3a: When the height of the stainless steel blank is higher than the upper limit of the preset height range, the stainless steel blank is repeatedly flattened until the height of the stainless steel blank is within the preset height range.
[0060] S103, die-forming the flattened stainless steel blank to obtain a stainless steel valve housing forging.
[0061] It should be understood that based on the above analysis of the causes of folding defects, it can be seen that the cause of folding defects in forgings is that the flattening height of the billet is too small. When the flattening height of the billet is too small, the metal flows in the vertical and horizontal directions of the mold cavity are not synchronized. When the metal flows horizontally to the burr bridge, the vertical direction of the cavity is not yet full. Under the action of the resistance of the burr bridge, the horizontal metal flows back and intersects with the vertical metal, resulting in folds on the surface of the forging.
[0062] The stainless steel valve housing forging method provided in the embodiment of the present application can flatten the stainless steel blank after upsetting to a preset height range, and the lower limit of the preset height range is the basic height in the flattening process requirements, and the upper limit of the preset height range is less than or equal to the sum of the basic height and the upper tolerance in the flattening process requirements. That is, when the present application performs the flattening process, the flattened height generally belongs to the higher part of the height in the process requirements, thereby avoiding folding defects when the stainless steel valve housing forging is pressed during die pressing.
[0063] In some embodiments, before forging, the preset height interval may be analyzed and determined. In this case, before the above S101, the method may further include the following steps: Step 1b: Determine multiple candidate heights according to the basic height, upper tolerance, and lower tolerance in the flattening process requirements.
[0064] For example, when the flattening height required by the above flattening process step is specifically 30 millimeters (mm) ±2 mm, the multiple candidate heights selected may be: 28 mm, 29 mm, 30 mm, 31 mm, and 32 mm.
[0065] Step 2b: numerically simulate the forming process of the stainless steel billet after upsetting when it is flattened to multiple candidate heights, and obtain simulation results corresponding to each of the multiple candidate heights.
[0066] The simulation results corresponding to the multiple candidate heights can refer to the above Figures 5 to 7 As shown in the place, no further description is given here.
[0067] Step 3b: Determine a preset height interval according to the simulation results corresponding to each of the multiple candidate heights.
[0068] For example, the candidate heights corresponding to the simulation results without folding can be selected as the heights in the preset height interval to obtain the preset height interval. Alternatively, the smallest candidate height among the candidate heights of the simulation results without folding is used as the lower limit of the preset height interval, and the largest candidate height is used as the upper limit of the preset height interval.
[0069] In some possible embodiments, after the stainless steel valve housing forging is obtained, the stainless steel valve housing forging may be subjected to fluorescent flaw detection.
[0070] In some possible embodiments, after obtaining the stainless steel valve housing forging, a magnifying glass may be used to check whether the stainless steel valve housing forging has folding defects.
[0071] In an exemplary embodiment, the embodiment of the present application further provides a stainless steel valve housing forging, which is forged using the above-mentioned stainless steel valve housing forging method.
[0072] Based on the above embodiments, the following conclusions can be drawn: (1) Through theoretical analysis and simulation tests, the root cause of the folding defect of the stainless steel valve housing forging was determined, and the valve housing forging process was optimized and improved to avoid the folding defect caused by forging die pressing.
[0073] (2) This application adopts an optimized and improved process for controlling the flattening height to obtain a valve housing forging without folding defects. This control method has reference significance for similar forging processes with a billet flattening step.
[0074] (3) Due to the complex shape of die forgings, the diverse material flow conditions during the deformation process, the difficulty in forming, and the complex actual production situation, in order to ensure product quality and reduce costs, further in-depth research is needed based on the actual production conditions of forgings to guide actual production.
[0075] Although the present application has been described in conjunction with specific features and embodiments thereof, it is obvious that various modifications and combinations may be made thereto without departing from the spirit and scope of the present application. Accordingly, this specification and the drawings are merely exemplary illustrations of the present application as defined by the appended claims, and are deemed to have covered any and all modifications, variations, combinations or equivalents within the scope of the present application. Obviously, those skilled in the art may make various modifications and variations to the present application without departing from the spirit and scope of the present application. Thus, if these modifications and variations of the present application fall within the scope of the claims of the present application and their equivalents, the present application is also intended to include these modifications and variations.
[0076] The above is only a specific implementation of the present application, but the protection scope of the present application is not limited thereto. Any changes or substitutions within the technical scope disclosed in the present application should be included in the protection scope of the present application. Therefore, the protection scope of the present application should be based on the protection scope of the claims.
Claims
1. A method for forging a stainless steel valve housing, characterized in that: The method comprises: The stainless steel blank is heated to the required temperature for one-fire die pressing, and the stainless steel blank is upset; the one-fire die pressing includes three steps of upsetting, flattening, and forming; Flatten the stainless steel billet after upsetting to a preset height range; the lower limit of the preset height range is the basic height in the process requirements of the flattening step; the upper limit of the preset height range is less than or equal to the sum of the basic height and the upper tolerance in the process requirements of the flattening step; The flattened stainless steel blank is die-formed to obtain a stainless steel valve housing forging.
2. The method according to claim 1, characterized in that The method of flattening the upset stainless steel blank to a preset height range includes: The stainless steel blank after upsetting is flattened to the preset height range by using a clamp; a height limiting block is arranged between the clamps; and the height of the height limiting block is the same as the basic height.
3. The method according to claim 2, characterized in that The height limiting block is detachably fixed on the clamp.
4. The method according to claim 2, characterized in that: The method of using a clamp to flatten the upset stainless steel blank to a preset height range includes: The stainless steel blank after upsetting is flattened by using a fixture; Measure the height of the stainless steel billet after flattening; When the height of the stainless steel blank is higher than the upper limit of the preset height range, the stainless steel blank is repeatedly flattened until the height of the stainless steel blank is within the preset height range.
5. The method according to claim 1, characterized in that: The basic height in the flattening process step process requirement is 30mm, the upper tolerance in the flattening process step process requirement is 2mm, and the lower tolerance in the flattening process step process requirement is -2mm; The lower limit of the preset height interval is 30 mm, and the upper limit of the preset height interval is 32 mm.
6. The method according to claim 1, characterized in that The stainless steel blank is 1Cr11Ni2W2MoV.
7. The method according to claim 1, characterized in that The method further comprises: Determine a plurality of candidate heights according to the basic height, the upper tolerance, and the lower tolerance in the process requirements of the flattening step; Performing numerical simulation on the forming step of the stainless steel billet after upsetting when it is flattened to the plurality of candidate heights, and obtaining simulation results corresponding to the plurality of candidate heights; The preset height interval is determined according to the simulation results corresponding to each of the multiple candidate heights.
8. The method according to claim 1, characterized in that The method further comprises: Use a magnifying glass to check whether the stainless steel valve housing forging has folding defects.
9. The method according to claim 1, characterized in that: The method further comprises: The stainless steel valve housing forging is subjected to fluorescent flaw detection.
10. A stainless steel valve housing forging, characterized in that: The stainless steel valve housing forging is forged by the forging method described in any one of claims 1 to 9.