Method for determining the initial ring blank feed size to inhibit missing defects in an internal profiled ring

Abstract

A method for determining the size of an initial ring blank for suppressing the missing defect of an inner profiled ring, comprising the following steps: step 1: determining the volume and longitudinal cross-sectional area of a target profiled ring according to the size of the target profiled ring; step 2: determining the design parameters and size of an initial rectangular cross-section ring blank according to the ring rolling volume conservation principle; step 3: determining the ring size when the profiled ring contour filling is completed; step 4: determining the material inflow volume of the profiled part of the ring in the diameter growth stage; and step 5: determining the size of the profiled cross-section ring blank after the initial rectangular cross-section ring blank is supplemented. The method can effectively solve the missing defect problem caused by insufficient metal inflow during the diameter growth of the profiled ring.

Description

Technical Field

[0001] This invention relates to the field of ring forming technology, specifically to a method for determining the initial ring blank filling size to suppress the defect of insufficient material in internal irregular ring parts. Background Technology

[0002] In the rolling process of irregularly shaped rings, unreasonable design of the cross-sectional geometry and dimensions of the ring blank can easily lead to forming defects such as insufficient material and warping, which in turn can cause the ring to exceed dimensional tolerances or even fail during rolling. During the rolling process of irregularly shaped rings, forming defects such as insufficient material mainly appear on the outer side of the large end of the irregularly shaped ring.

[0003] The ring rolling process for irregularly shaped rings includes two stages: contour filling and diameter growth. The longitudinal cross-sectional geometry of the irregularly shaped ring can be decomposed into a rectangular section and an irregularly shaped section. After contour filling, during the diameter growth stage, the rectangular section thins as its thickness decreases, and the ring diameter continuously increases. However, the area of ​​the irregularly shaped section remains constant during the diameter growth stage. As the diameter continues to increase, a large influx of metal material is required to meet the needs of this diameter growth. Axial metal flow is very difficult during the rolling process of irregularly shaped rings. Therefore, metal material tends to flow radially from the outer side of the ring at a constant height to replenish the metal material needed for the irregularly shaped section, leading to a missing portion defect on the outer side of the larger end of the irregularly shaped ring.

[0004] Chinese patent CN101829686A discloses a method for determining the size of a radially axially rolled ring blank for rectangular cross-section rings. This method is only applicable to determining the size of a rectangular cross-section ring blank and is not suitable for rolling irregularly shaped rings. Chinese patent CN117798291A discloses a method and apparatus for determining the initial blank size of a large bearing ring end-rolling. This method is mainly based on the principle of equal volume, calculating the volume and size of the rectangular ring blank based on the volume of the target irregularly shaped ring. It does not consider the problem of insufficient material forming defects during the rolling process of irregularly shaped rings, making it difficult to guarantee the final forming integrity of the irregularly shaped ring. Chinese patent CN109794568B discloses a method for determining the size of a rolled blank for rings with irregular inner and outer surfaces. This method determines the size of the intermediate ring blank based on the principle of equal volume. However, it is only applicable to rings with axially symmetrical cross-sections and is not suitable for rings with asymmetrical cross-sections. Furthermore, its irregularly shaped ring forming process does not consider the problem of insufficient metal inflow causing insufficient material forming defects. Summary of the Invention

[0005] The technical problem to be solved by the present invention is to overcome the shortcomings of the above-mentioned background technology and provide a method for determining the initial ring blank feeding size to suppress the defect of insufficient metal in the inner irregular ring part, which can effectively solve the problem of insufficient metal inflow during the growth of the irregular ring diameter.

[0006] The technical solution adopted by this invention to solve its technical problem is a method for determining the initial ring blank feeding size to suppress the defect of insufficient material in internal irregular ring parts, comprising the following steps: Step 1: Determine the volume of the target irregular-shaped ring based on its dimensions. and longitudinal cross-sectional area ;

[0007] Step 2: Based on the principle of volume conservation in ring rolling, determine the design parameters and dimensions of the initial rectangular cross-section ring blank; Step 3: Determine the ring size after the irregular ring contour filling is completed; Step 4: Determine the material inflow volume of the irregularly shaped portion of the ring during the diameter growth stage; Step 5: Determine the dimensions of the irregular cross-section ring blank after the initial rectangular cross-section ring blank is fed.

[0008] Furthermore, in step 1, the volume of the target irregularly shaped ring is determined. and longitudinal cross-sectional area The method is as follows: (1) (2) in, The outer radius of the target irregular ring component, For the small end wall thickness of the target irregular ring component, For the height of the target irregular ring component, Let be the inner contour function of the longitudinal section of the target irregular ring component. The origin is taken as the inner end of the small end of the longitudinal section of the target irregular ring, the height direction is x, and the radial direction is y.

[0009] Furthermore, in step 2, the method for determining the design parameters and dimensions of the initial rectangular cross-section ring blank is as follows: Step 1-1: Set the design parameters and rolling ratio for the initial rectangular cross-section ring billet. Rolling ratio The longitudinal cross-sectional area of ​​the initial rectangular cross-section ring blank and the longitudinal cross-sectional area of ​​the target irregular ring component The ratio: (4) in, Let be the longitudinal cross-sectional area of ​​the initial rectangular cross-section ring blank. The initial rectangular cross-section ring blank height, The initial rectangular cross-section circumferential blank wall thickness; Step 1-2: Determine the dimensions of the initial rectangular cross-section ring blank based on the principle of volume conservation during the ring rolling process; The volume conservation principle during the ring rolling process is as follows: (5) In the formula, The volume of the ring component is the initial rectangular cross-section ring blank. The volume of the ring component when the ring component contour is filled. The volume of the irregular cross-section ring blank after feeding the initial rectangular cross-section ring blank; Steps 1-3: Combine equations (1), (2), (4), and (5) to obtain the outer radius of the initial rectangular cross-section ring blank. and wall thickness : (6) (7) In the formula, For rolling ratio, The longitudinal cross-sectional area of ​​the target irregular ring component. The height of the target irregular ring component, The volume of the target irregular ring component.

[0010] Furthermore, in step 3, the method for determining the ring size after the irregular ring contour filling is completed is as follows: Step 3-1, Define the stretch factor The difference between the wall thickness reduction at the large end and the wall thickness reduction at the small end during the ring contour filling stage is expressed as shown in (8): (8) Where D is the target annular groove depth. The wall thickness at the small end when the contour filling of the irregular ring component is completed; Step 3-2: Calculate the small end wall thickness after contour filling is completed based on the stretching coefficient of the ring during the contour filling stage. : (9) in, The wall thickness at the smaller end when the contour filling is complete; Step 3-3: Obtain the outer radius when the contour filling is completed based on the principle of volume conservation during the rolling forming process. : (10) in, The outer radius when the contour is filled.

[0011] Furthermore, in step 4, the method for determining the material inflow volume of the irregular portion of the ring during the diameter growth stage is as follows: Based on the dimensions of the ring when the contour filling is completed and the final dimensions of the target irregular ring, the theoretical inflow volume of material at different heights x of the irregular portion of the ring during the diameter growth stage is calculated. That is, the volume of the micro-ring of the irregular part of the target irregular ring component. Subtract the volume of the irregular ring element when the contour filling is complete. As shown in equation (11): (11) In the formula, This represents the theoretical inflow volume of material at different heights x for the irregularly shaped portion of the ring during the diameter growth stage.

[0012] Furthermore, in step 5, the method for determining the dimensions of the irregular cross-section ring blank after feeding the initial rectangular cross-section ring blank is as follows: Based on the material inflow volume of the irregularly shaped portion of the ring during the diameter growth stage obtained in step 4, and based on the principle of equal-height material replenishment, the theoretical inflow volume at different heights x will be calculated. The filler material is applied to the outside of the initial rectangular cross-section ring blank, transforming it into a ring blank with an irregular cross-section on the outside. Its dimensions include the outer radius of the small end of the irregular cross-section ring blank after the filler material is applied. Small end wall thickness Outer contour function , Taking the outer end of the small end of the longitudinal section of the irregular cross-section ring blank after replenishment as the origin, the height direction is the x-direction, and the radial direction is the y-direction. That is, the outer line function of the longitudinal section of the irregular cross-section ring blank after material replenishment.

[0013] Furthermore, the principle of equal-height feeding is as shown in equation (12): (12) This refers to the volume of the micro-ring of the irregular cross-section ring blank after material replenishment; The outer radius of the small end of the irregular cross-section ring blank after replenishment is the same as the outer radius of the initial rectangular cross-section ring blank, that is... = ; Based on the principle of equal-height feeding, the outer contour function of the irregular cross-section ring blank after feeding is obtained. for: (13) Based on the principle of volume conservation during the rolling process, the wall thickness of the small end of the irregular cross-section ring billet after feeding is obtained. for: (14).

[0014] Compared with the prior art, the advantages of the present invention are as follows: This invention aims to minimize the axial metal flow during the rolling process of irregularly shaped rings. Based on the specific dimensions of the irregularly shaped rings within the target area, and using a partitioning approach and the principle of equal volume, it accurately calculates the required volumetric inflow of the irregularly shaped micro-rings at different heights during the diameter growth of the irregularly shaped rings. This yields the dimensions of the irregularly shaped cross-section ring blank after the initial rectangular cross-section is filled with material. By accurately filling the volumetric inflow to the initial irregularly shaped cross-section ring blank at the corresponding height, the problem of insufficient metal flow during the diameter growth of the irregularly shaped rings can be effectively solved, thus avoiding the destruction of the internal flow lines of the irregularly shaped rings by subsequent machining and the reduction of the mechanical properties of the rings. Attached Figure Description

[0015] Figure 1 This is a flowchart of the method according to an embodiment of the present invention.

[0016] Figure 2 These are schematic diagrams of longitudinal sections at different stages of the rolling process of irregularly shaped rings. Among them, (2a) is a schematic diagram of the longitudinal section of the initial rectangular cross-section ring blank, (2b) is a schematic diagram of the longitudinal section when the outline of the irregularly shaped ring is filled, and (2c) is a schematic diagram of the longitudinal section of the target irregularly shaped ring.

[0017] Figure 3 This is a schematic diagram of the longitudinal section of the irregular cross-section ring blank after material replenishment.

[0018] Figure 4 It is the theoretical inflow volume of the micro-ring at different heights of the longitudinal section of the irregular cross-section ring blank after feeding.

[0019] Figure 5 It refers to the filling width at different heights of the longitudinal section of the irregular cross-section ring blank after filling.

[0020] Figure 6 The figures show a comparison of the forming effects of the non-feeding method and the feeding method of the present invention: (6a) is a schematic diagram of ring rolling forming; (6b) is a forming effect diagram of the non-feeding method; and (6c) is a forming effect diagram of the method of the present invention. Detailed Implementation

[0021] The present invention will now be described in further detail with reference to the accompanying drawings and specific embodiments.

[0022] This invention addresses the problem of insufficient material forming during the rolling process of irregularly shaped ring parts. It involves first replenishing the initial rectangular cross-section ring blank, then filling the contour and increasing the diameter to form the target irregularly shaped ring part. Determining the replenishment size of the initial rectangular cross-section ring blank is the key to this invention. The target irregularly shaped ring part of this invention is an inner irregularly shaped ring part, meaning its longitudinal section consists of a rectangular section and an irregularly shaped section; the outer part is rectangular, and the inner part is irregularly shaped. The method for determining the initial ring blank replenishment size to suppress the insufficient material forming defect in inner irregularly shaped ring parts is as follows: Figure 1 As shown, it includes the following steps: Step 1: Determine the volume of the target irregular-shaped ring based on its dimensions. and longitudinal cross-sectional area ;

[0023] (1) (2) in, The outer radius of the target irregular ring component, For the small end wall thickness of the target irregular ring component, For the height of the target irregular ring component, This is the inner contour function of the longitudinal section of the target irregular ring component, that is, the inner line function of the longitudinal section of the target irregular ring component. The origin is taken as the inner end of the small end of the longitudinal section of the target irregular ring, the height direction is x, and the radial direction is y.

[0024] In this example, the rolling process for the target irregularly shaped ring is as follows: Figure 2 As shown in the table below, the dimensions of the target ring are as follows: ; In this embodiment, the inner contour function f(x) of the target ring's transverse and longitudinal surfaces is a piecewise function, expressed as: (3) The longitudinal cross-sectional area of ​​the target irregular ring is calculated according to equations (1), (2), and (3). It is 54871.00 mm. 2 ,volume It is 557876679.08 mm. 3 .

[0025] Step 2: Based on the principle of volume conservation in ring rolling, determine the design parameters and dimensions of the initial rectangular cross-section ring blank; like Figure 2As shown, the initial rectangular cross-section of the ring blank has a rectangular longitudinal section. The height of the irregular ring remains unchanged during the rolling process. Only radial rolling occurs during the rolling process, which reduces the thickness of the ring. The axial rolling zone does not feed, and the height of the ring remains unchanged.

[0026] Setting the design parameters and rolling ratio of the initial rectangular cross-section ring billet Rolling ratio The longitudinal cross-sectional area of ​​the initial rectangular cross-section ring blank and the longitudinal cross-sectional area of ​​the target irregular ring component The ratio: (4) in, Let be the longitudinal cross-sectional area of ​​the initial rectangular cross-section ring blank. The initial rectangular cross-section ring blank height, The initial rectangular cross-section ring blank wall thickness is given.

[0027] Based on the principle of volume conservation during the ring rolling process, the dimensions of the initial rectangular cross-section ring blank are determined; The principle of volume conservation in the ring rolling process states that the volume of the ring remains unchanged regardless of when it is in the rolling process (initial rectangular cross-section ring blank, ring after contour filling, target ring, etc.). (5) In the formula, The volume of the ring component is the initial rectangular cross-section ring blank. The volume of the ring component when the ring component contour is filled. The volume of the irregular cross-section ring blank after the initial rectangular cross-section ring blank is filled with material.

[0028] The initial rectangular cross-section ring blank has a rectangular longitudinal section, the dimensions of which include the outer radius. and wall thickness By combining equations (1), (2), (4), and (5), we obtain: (6) (7) In this embodiment, the initial rolling ratio is determined. The value is 2.1. The wall thickness of the initial rectangular cross-section ring blank was calculated. It is 256mm, outer radius It is 898.5mm.

[0029] Step 3: Determine the ring size after the irregular ring contour filling is completed; The dimensional parameters of the irregularly shaped ring after the contour filling is completed include the outer radius of the ring. and small end wall thickness When the ring profile is filled, the inner profile shape of the longitudinal section is formed. The specific criterion is that the groove depth (the difference between the wall thickness of the large end and the wall thickness of the small end of the ring) reaches the groove depth value of the target ring.

[0030] Because the ring exhibits a stretching-shrinkage phenomenon during contour filling—that is, the active feeding deformation of the small end of the ring by the core roller causes the large end of the ring, which is not in direct contact with the core roller, to passively deform, resulting in a reduction in wall thickness—a stretching-shrinkage coefficient is defined. The difference between the wall thickness reduction at the large end and the wall thickness reduction at the small end during the ring contour filling stage is expressed as shown in (8).

[0031] (8) Where D is the target annular groove depth. The wall thickness at the small end when the contour of the irregular ring is filled.

[0032] The small end wall thickness when the contour filling is completed is obtained based on the stretching coefficient of the ring during the contour filling stage. As shown in equation (9); the outer radius when the contour filling is completed can be obtained according to the volume conservation principle of the rolling forming process. As shown in equation (10): (9) (10) In this embodiment, the stretching coefficient is set during the ring contour filling stage. The wall thickness of the small end of the irregular ring can be determined by calculation when the contour filling is completed. It is 168.5mm, outer radius It is 1472mm.

[0033] Step 4: Determine the material inflow volume of the irregularly shaped ring during the diameter growth stage; based on the dimensions of the ring after contour filling and the final dimensions of the target irregularly shaped ring, calculate the theoretical material inflow volume of the irregularly shaped ring at different heights x during the diameter growth stage. That is, the volume of the micro-ring of the irregular part of the target irregular ring component. Subtract the volume of the irregular ring element when the contour filling is complete. As shown in equation (11): (11) Calculations show that the theoretical inflow volume of material in the irregularly shaped part of the ring at different heights x during the diameter growth stage is as follows: ,like Figure 4 As shown.

[0034] Step 5: Determine the dimensions of the irregular cross-section ring blank after feeding the initial rectangular cross-section ring blank: Based on the material inflow volume of the irregularly shaped portion of the ring during the diameter growth stage obtained in step 4, and based on the principle of equal-height material replenishment, the theoretical inflow volume at different heights x will be calculated. The feed material is added to the outside of the initial rectangular cross-section ring blank, transforming it into a ring blank with an irregular cross-section on the outside, such as... Figure 3 Its dimensions include: the outer radius of the small end of the irregular cross-section ring blank after feeding. Small end wall thickness Outer contour function , Taking the outer end of the small end of the longitudinal section of the irregular cross-section ring blank after replenishment as the origin, the height direction is the x-direction, and the radial direction is the y-direction. That is, the outer line function of the longitudinal section of the irregular cross-section ring blank after material replenishment.

[0035] The principle of equal-height feeding is shown in equation (12): (12) This refers to the volume of the micro-ring of the irregular cross-section ring blank after material replenishment; The outer radius of the small end of the irregular cross-section ring blank after replenishment is the same as the outer radius of the initial rectangular cross-section ring blank, that is... = =898.5mm.

[0036] Based on the principle of equal-height feeding, the outer contour function of the irregular cross-section ring blank after feeding is obtained. for: (13) Based on the principle of volume conservation during the rolling process, the wall thickness of the small end of the irregular cross-section ring billet after feeding is obtained. for: (14) After calculation, the outer contour function of the irregular cross-section ring blank after material replenishment was determined. like Figure 5 As shown, the wall thickness of the small end of the irregular cross-section ring blank after feeding is... It is 246.5mm.

[0037] Step 6: Verify the rationality of the initial rolling ratio: In this invention, the ring rolling process starts from the initial rectangular cross-section ring blank. Therefore, it is required that the mandrel can be placed inside the irregular ring blank, that is, the inner diameter of the initial rectangular cross-section ring blank should be greater than the outer diameter of the mandrel. The criterion is shown in Equation (15): if the criterion is met, it means that the initial rolling ratio is qualified and the supplementary blank can be designed according to the design parameters. Otherwise, it means that the rolling ratio is too large and the rolling ratio should be reduced. Then, return to step 2 to design the initial rectangular cross-section ring blank.

[0038] In equation (15), The diameter of the core roller.

[0039] core roll diameter during rolling process It is 620mm, 2 (R0-B) c =2×(898.5-246.5)=1304mm, which is greater than the core roll diameter of 620mm. The initial rolling ratio is qualified after calculation.

[0040] This example uses Abaqus software for simulation. The numerical simulation results show the following formation effect: Figure 6 As shown in the figure, the modified shaping effect is good, effectively reducing the defects of incomplete shaping.

[0041] Those skilled in the art can make various modifications and variations to this invention. If such modifications and variations are within the scope of the claims of this invention and their equivalents, then such modifications and variations are also within the protection scope of this invention.

[0042] The contents not described in detail in the specification are prior art known to those skilled in the art.

Claims

1. A method for determining the initial ring blank feeding size to suppress the missing material defect in internal irregularly shaped ring parts, characterized in that, Includes the following steps: Step 1: Determine the volume of the target irregular-shaped ring based on its dimensions. and longitudinal cross-sectional area ; Step 2: Based on the principle of volume conservation in ring rolling, determine the design parameters and dimensions of the initial rectangular cross-section ring blank; Step 3: Determine the ring size after the irregular ring contour filling is completed; Step 4: Determine the material inflow volume of the irregularly shaped portion of the ring during the diameter growth stage; Step 5: Determine the dimensions of the irregular cross-section ring blank after the initial rectangular cross-section ring blank is fed.

2. The method for determining the initial ring blank feeding size to suppress the missing material defect in the inner irregular ring part as described in claim 1, characterized in that: In step 1, the volume of the target irregular ring component is determined. and longitudinal cross-sectional area The method is as follows: （1） （2） in, The outer radius of the target irregular ring component, For the small end wall thickness of the target irregular ring component, For the height of the target irregular ring component, Let be the inner contour function of the longitudinal section of the target irregular ring component. The origin is taken as the inner end of the small end of the longitudinal section of the target irregular ring, the height direction is x, and the radial direction is y.

3. The method for determining the initial ring blank feeding size to suppress the missing material defect in the inner irregular ring part as described in claim 2, characterized in that: In step 2, the method for determining the design parameters and dimensions of the initial rectangular cross-section ring blank is as follows: Step 1-1: Set the design parameters and rolling ratio for the initial rectangular cross-section ring billet. Rolling ratio The longitudinal cross-sectional area of ​​the initial rectangular cross-section ring blank and the longitudinal cross-sectional area of ​​the target irregular ring component The ratio: （4） in, Let be the longitudinal cross-sectional area of ​​the initial rectangular cross-section ring blank. The initial rectangular cross-section ring blank height, The initial rectangular cross-section circumferential blank wall thickness; Step 1-2: Determine the dimensions of the initial rectangular cross-section ring blank based on the principle of volume conservation during the ring rolling process; The volume conservation principle during the ring rolling process is as follows: （5） In the formula, The volume of the ring component is the initial rectangular cross-section ring blank. The volume of the ring component when the ring component contour is filled. The volume of the irregular cross-section ring blank after feeding the initial rectangular cross-section ring blank; Steps 1-3: Combine equations (1), (2), (4), and (5) to obtain the outer radius of the initial rectangular cross-section ring blank. and wall thickness : （6） （7） In the formula, For rolling ratio, The longitudinal cross-sectional area of ​​the target irregular ring component. The height of the target irregular ring component, The volume of the target irregular ring component.

4. The method for determining the initial ring blank feeding size to suppress the missing material defect in the inner irregular ring part as described in claim 3, characterized in that: In step 3, the method for determining the ring size after the irregular ring contour filling is completed is as follows: Step 3-1, Define the stretch factor The difference between the wall thickness reduction at the large end and the wall thickness reduction at the small end during the ring contour filling stage is expressed as shown in (8): （8） Where D is the target annular groove depth. The wall thickness at the small end when the contour filling of the irregular ring component is completed; Step 3-2: Calculate the small end wall thickness after contour filling is completed based on the stretching coefficient of the ring during the contour filling stage. : （9） in, The wall thickness at the smaller end when the contour filling is complete; Step 3-3: Obtain the outer radius when the contour filling is completed based on the principle of volume conservation during the rolling forming process. : （10） in, The outer radius when the contour is filled.

5. The method for determining the initial ring blank feeding size to suppress the missing material defect in the inner irregular ring part as described in claim 4, characterized in that: In step 4, the method for determining the material inflow volume of the irregular portion of the ring during the diameter growth stage is as follows: Based on the dimensions of the ring when the contour filling is completed and the final dimensions of the target irregular ring, the theoretical inflow volume of material at different heights x of the irregular portion of the ring during the diameter growth stage is calculated. That is, the volume of the micro-ring of the irregular part of the target irregular ring component. Subtract the volume of the irregular ring element when the contour filling is complete. As shown in equation (11): （11） In the formula, This represents the theoretical inflow volume of material at different heights x for the irregularly shaped portion of the ring during the diameter growth stage.

6. The method for determining the initial ring blank feeding size to suppress the missing material defect in the inner irregular ring part as described in claim 5, characterized in that: In step 5, the method for determining the dimensions of the irregular cross-section ring blank after feeding the initial rectangular cross-section ring blank is as follows: Based on the material inflow volume of the irregularly shaped portion of the ring during the diameter growth stage obtained in step 4, and based on the principle of equal-height material replenishment, the theoretical inflow volume at different heights x will be calculated. The filler material is applied to the outside of the initial rectangular cross-section ring blank, transforming it into a ring blank with an irregular cross-section on the outside. Its dimensions include the outer radius of the small end of the irregular cross-section ring blank after the filler material is applied. Small end wall thickness Outer contour function , Taking the outer end of the small end of the longitudinal section of the irregular cross-section ring blank after replenishment as the origin, the height direction is the x-direction, and the radial direction is the y-direction. That is, the outer line function of the longitudinal section of the irregular cross-section ring blank after material replenishment.

7. The method for determining the initial ring blank feeding size to suppress the missing material defect in the inner irregular ring part as described in claim 6, characterized in that: The principle of equal-height feeding is shown in equation (12): (12) This refers to the volume of the micro-ring of the irregular cross-section ring blank after material replenishment; The outer radius of the small end of the irregular cross-section ring blank after replenishment is the same as the outer radius of the initial rectangular cross-section ring blank, that is... = ; Based on the principle of equal-height feeding, the outer contour function of the irregular cross-section ring blank after feeding is obtained. for: （13） Based on the principle of volume conservation during the rolling process, the wall thickness of the small end of the irregular cross-section ring billet after feeding is obtained. for: （14）。

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