Plate forging forming method and die for r-shaped fork ring part

Abstract

The invention provides a plate forging forming die of an r-shaped fork ring part, the plate forging forming die comprises a necking extrusion male die, a shearing male die, a female die, a female die base plate, a nitrogen spring, a floatable mandrel, an upper die base and a lower die base, the invention further provides a plate forging forming method of the r-shaped fork ring part, and a pipe blank with the outer diameter equal to that of a cylindrical target part is placed on the female die base plate; the floating mandrel is kept still, and the necking extrusion male die moves downwards until a rib plate with the thickness equal to the wall thickness of the target part is formed at the upper end of the pipe blank; the necking extrusion male die is replaced with the shearing male die, the male die moves downwards to force the metal material to continuously flow to a semi-closed cavity defined by the shearing male die and the floating mandrel in a shearing deformation mode, finally, the floating mandrel or the lower ejector rod ejects the part out, demolding is completed, and a target part is obtained. According to the forming method, the r-shaped fork ring part is formed in a limited working procedure, the defects that parts with complex characteristics are difficult to form and low in material utilization rate are effectively overcome, and the forming method has the advantages of being simple in working procedure, low in forming load, high in forming precision and the like.

Description

Technical Field

[0001] The invention relates to the technical field of metal plastic forming, in particular to a forging forming method and a die for an R-shaped fork ring part plate. Background Art

[0002] The fork ring is an important component of the fuel tank of an aviation rocket. Therefore, the performance of the fork ring will directly affect the launch success rate and carrying capacity of the rocket. However, due to its extreme geometric shape (the flange and the cylinder wall are at an angle less than 90 degrees) and high performance requirements, the R-shaped fork ring part is difficult to manufacture efficiently and at low cost. At present, machining is a relatively effective way to produce such R-shaped fork ring parts, but it still has the disadvantages of low material utilization and poor mechanical properties.

[0003] Therefore, how to change the current situation of low efficiency, high cost and poor mechanical properties in the forming of R-shaped fork ring parts in the prior art has become an urgent problem to be solved by technical personnel in this field. Summary of the invention

[0004] The purpose of the present invention is to provide a plate forging forming method and a die for an R-shaped fork ring part to solve the problems existing in the above-mentioned prior art and improve material utilization, production efficiency and forming performance.

[0005] To achieve the above-mentioned purpose, the present invention provides the following scheme: The present invention provides a plate forging forming die for an R-shaped fork ring part, comprising a shrinking extrusion punch, a shearing punch, a die, a die pad, a nitrogen spring, a floating mandrel, an upper die seat and a lower die seat, wherein the shrinking punch and the shearing punch can be fixed to the upper die seat by screws and pins, the die pad is arranged at the bottom of the die and the two are connected and positioned on the lower die seat, the floating mandrel is slidably connected to the die pad, the floating mandrel can extend into the die, and there is a gap between the outer wall of the floating mandrel and the inner wall of the die, the floating mandrel is placed on the nitrogen spring, the nitrogen spring is fixed on the lower die seat, and the limiting elements are all limiting blocks on the press.

[0006] Preferably, the inner wall of the necking extrusion punch has an angle with the axial direction, the inner wall of the shearing punch also has an angle with the axial direction, and the angles of the two are equal.

[0007] Preferably, the upper end of the floating mandrel has the same angle as the inner wall of the necking extrusion punch.

[0008] The present invention also provides a plate forging method for an R-shaped fork ring part, using the plate forging die for the R-shaped fork ring part, comprising the following steps: Step 1: Place a tube blank with an outer diameter equal to that of the cylindrical target part on the die pad, keep the floating mandrel stationary, and move the shrinking extrusion punch downward until a rib plate with a thickness equal to that of the target part is formed on the upper end of the tube blank; Step 2: Replace the necking extrusion punch with a shearing punch, and the downward movement of the punch forces the metal material to continuously flow into the semi-enclosed cavity surrounded by the shearing punch and the floating mandrel by shearing deformation; Step 3: Use the floating mandrel or the lower ejector to eject the part to complete demoulding; Preferably, in step 2, the shearing punch and the floating mandrel move downward synchronously.

[0009] Compared with the prior art, the present invention has achieved the following technical effects: the plate forging forming die of the R-shaped fork ring part of the present invention includes a shrinking extrusion punch, a shearing punch, a die, a die pad, a nitrogen spring, a floating mandrel, an upper die seat and a lower die seat, the shrinking punch and the shearing punch can be fixed to the upper die seat by screws and pins, the die pad is arranged at the bottom of the die and the two are connected and positioned on the lower die seat, the floating mandrel is slidably connected to the die pad, the floating mandrel can extend into the die, and there is a gap between the outer wall of the floating mandrel and the inner wall of the die, the floating mandrel is placed on the nitrogen spring, the nitrogen spring is fixed on the lower die seat, and the limiting elements are all limiting blocks on the press. The present invention also provides a plate forging forming method of an R-shaped fork ring part, wherein a tube blank having an outer diameter equal to that of a cylindrical target part is placed on a die pad, the floating mandrel remains stationary, and the shrinking extrusion punch moves downward until a rib having a thickness equal to that of the target part is formed at the upper end of the tube blank; the shrinking extrusion punch is replaced with a shearing punch, and the downward movement of the punch forces the metal material to continuously flow to the semi-enclosed cavity surrounded by the shearing punch and the floating mandrel through shear deformation, and finally the floating mandrel or the lower ejector pushes the part out, and demolding is completed to obtain the target part. The present invention realizes the forming of an R-shaped fork ring within a limited process, effectively solving the disadvantages of the difficulty in forming such parts and the low material utilization rate, and has the advantages of simple process, low forming load and high forming precision. BRIEF DESCRIPTION OF THE DRAWINGS

[0010] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0011] Figure 1 It is a schematic diagram of the cross-section structure of the R-shaped fork ring part plate forging forming die of the present invention when working in step 1; Figure 2It is a schematic diagram of the cross-section structure of the R-shaped fork ring part plate forging forming die of the present invention when working in step 2; Figure 3 A schematic diagram of a tube blank formed by the R-shaped fork ring part plate forging forming method of the present invention; Figure 4 It is a schematic diagram of a part formed by shrinking and extruding using the forging forming method of an R-shaped fork ring part plate of the present invention; Figure 5 It is a schematic diagram of a part after shearing and forming by using the R-shaped fork ring part plate forging forming method of the present invention; Among them, 1 is the shrinking extrusion punch, 2 is the floating mandrel, 3 is the die, 4 is the die pad, 5 is the nitrogen spring, 6 is the shearing punch, 7 is the upper die seat, 8 is the lower die seat, D is the outer diameter of the tube, d 0 is the inner diameter of the tube, d 1 is the minimum inner diameter of the part after shrinking. d 2 is the minimum inner diameter of the part after shearing. t 0 is the wall thickness of the tube blank, h 0 is the height of the tube, h 1 is the height of the part after shrinking, h 2 is the height of the part after shearing. t 1 is the thickness of the rib plate of the fork ring part, t 2 is the thickness of the straight wall part at the upper end of the fork ring part, α It is the shrinkage angle, and also the inclination angle of the rib of the fork ring part. DETAILED DESCRIPTION

[0012] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. 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] The purpose of the present invention is to provide a plate forging forming die for an R-shaped fork ring part to solve the problems existing in the above-mentioned prior art and improve the production efficiency and mechanical properties of the formed parts.

[0014] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, the present invention is further described in detail below with reference to the accompanying drawings and specific embodiments.

[0015] Please refer to Figure 1-5 ,in, Figure 1 This is a schematic diagram of the cross-sectional structure of the R-shaped fork ring part plate forging die of the present invention when working in step 1. Figure 2It is a schematic diagram of the cross-section structure of the R-shaped fork ring part plate forging forming die of the present invention when working in step 2, Figure 3 Schematic diagram of a tube blank formed by the R-shaped fork ring part plate forging forming method of the present invention, Figure 4 This is a schematic diagram of a part after the R-shaped fork ring part plate is formed by shrinking and extruding using the forging forming method of the present invention. Figure 5 It is a schematic diagram of a part after shearing and forming using the R-shaped fork ring part plate forging forming method of the present invention.

[0016] The present invention provides a cylindrical plate forging forming die with a small fillet feature, comprising a shrinking extrusion punch 1, a shearing punch 6, a die 3, a die pad 4, a nitrogen spring 5, a floating mandrel 2, an upper die seat 7 and a lower die seat 8. The shrinking punch 1 and the shearing punch 6 can be fixed to the upper die seat 7 by screws and pins. The die pad 4 is arranged at the bottom of the die 3 and the two are connected and positioned on the lower die seat 8. The floating mandrel 2 is slidably connected to the die pad 4. The floating mandrel 2 can extend into the die 3, and there is a gap between the outer wall of the floating mandrel 2 and the inner wall of the die 3. The floating mandrel 2 is placed on the nitrogen spring 5, and the nitrogen spring 5 is fixed on the lower die seat 8. The limiting elements are all limiting blocks on a press.

[0017] When using the cylindrical plate forging forming die with small fillet characteristics of the present invention, a tube blank with an outer diameter equal to that of the cylindrical target part is placed on the die pad 4, the floating mandrel 2 remains stationary, and the shrinking extrusion punch 1 moves downward until a rib plate with a thickness equal to that of the target part is formed at the upper end of the tube blank; the shrinking extrusion punch 1 is replaced with a shearing punch 6, and the downward movement of the punch 6 forces the metal material to continuously flow to the semi-enclosed cavity surrounded by the shearing punch 6 and the floating mandrel 2 by shear deformation, and finally the floating mandrel 2 or the lower ejector pushes the part out, completes demoulding, and obtains the target part. The present invention realizes the formation of an R-shaped fork ring within a limited number of processes, effectively solves the shortcomings of the difficulty in forming such parts and the low material utilization rate, and has the advantages of simple process, low forming load, and high forming accuracy. It should be noted that the shrinking extrusion punch 1, the shearing punch 6 and the floating mandrel 2 can all be connected to a press, which can drive the shrinking extrusion punch 1, the shearing punch 6 and the floating mandrel 2 to reciprocate respectively, and the floating mandrel 2 can also be connected to the nitrogen spring 5.

[0018] In this specific embodiment, the limiting elements are all limiting blocks on the press, and during the forming step 1, it should be ensured that the bottom dead point position of the necking extrusion punch has a gap with the upper end of the die.

[0019] In this specific embodiment, the floating mandrel 2 and the die backing plate 4 are matched with H7 / g6.

[0020] The present invention also provides a plate forging method for an R-shaped fork ring part, using the plate forging die for the R-shaped fork ring part, comprising the following steps: Step 1: According to the characteristics of the cylindrical target part, a cylindrical part with an outer diameter of D , wall thickness is t 0, height is h 0 tube blank, the tube blank is positioned on the die pad 4 with the outer tube wall as the positioning. The press has a hydraulic cylinder output mechanism at the bottom, the shrinking extrusion punch 1 is connected to the slider in the main cylinder of the press, and the floating mandrel 2 is connected to the nitrogen spring 2. First, the floating mandrel 2 moves to the upper limit under the action of the floating mandrel and remains stationary, and then the main cylinder of the press drives the punch 1 to move downward at a uniform speed to form the upper end surface of the tube blank to form a shrinking extrusion part, such as Figure 4 As shown, the height of the part after shrinkage extrusion is h 1. Minimum inner diameter is d 1. Rib wall thickness is t 1. The shrinking angle is α .

[0021] Step 2: The main cylinder of the press moves upward to drive the punch 1 to move to the upper limit and then remains stationary, and then the shearing punch 6 is replaced. Then the main cylinder of the press drives the shearing punch 6 to continue to move downward, forcing the metal to continuously flow into the semi-enclosed cavity surrounded by the shearing punch 6 and the floating mandrel 2, thereby shearing out a tubular part with an inclined rib in the middle, such as Figure 5 As shown, the part height is h 2. Minimum inner diameter is d 2. The upper wall thickness is t 2. The wall thickness of the lower end is t 0, t 0. t 1. t 2 The thickness of the three places may be different. It should be noted that, here, the lower limit position can be specifically set according to the specific target formed part.

[0022] Step 3: After the part is formed, the demolding process is carried out. The floating mandrel 2 connected to the hydraulic cylinder below the press remains stationary, and the main cylinder of the press drives the shear punch 6 to return and separate from the part. Then the hydraulic cylinder below the press drives the floating mandrel 2 upward to push the part out of the die 3.

[0023] Specifically, the inner wall of the necking extrusion punch 1 has an angle with the axial direction. α The inner wall of the shearing punch 6 also has the same angle with the axial direction α Similarly, the upper end of the floating mandrel also has the same angle as the inner wall of the shrinking extrusion punch. α , the specific size can be adjusted according to the target part size.

[0024] In step 2, the shearing punch 6 and the floating mandrel 2 move downward synchronously.

[0025] The present invention uses specific examples to illustrate the principles and implementation methods of the present invention. The above examples are only used to help understand the method and core ideas of the present invention. At the same time, for those skilled in the art, according to the ideas of the present invention, there will be changes in the specific implementation methods and application scope. In summary, the content of this specification should not be understood as limiting the present invention.

Claims

1. A plate forging method for an R-shaped fork ring part, using a plate forging die for an R-shaped fork ring part, can efficiently and low-cost produce a fork ring part with extreme geometric features, characterized in that: It includes the shrinking extrusion punch of step one, the shearing punch of step two, and the die of steps one, two and three, the die pad, the nitrogen spring, the floating mandrel, the upper die seat and the lower die seat. The shrinking punch and the shearing punch can be fixed to the upper die seat by screws and pins. The die pad is arranged at the bottom of the die and the two are connected and positioned on the lower die seat. The floating mandrel is slidably connected to the die pad. The floating mandrel can extend into the die, and there is a gap between the outer wall of the floating mandrel and the inner wall of the die. The floating mandrel is placed on the nitrogen spring, and the nitrogen spring is fixed on the lower die seat. The limiting elements are all limiting blocks on the press. The forming method includes the following steps: Step 1: Place a tube blank with an outer diameter equal to that of the cylindrical target part on the die pad, keep the floating mandrel stationary, and move the shrinking extrusion punch downward until a rib plate with a thickness equal to that of the target part is formed on the upper end of the tube blank; Step 2: Replace the necking extrusion punch with a shearing punch, and the downward movement of the punch forces the metal material to continuously flow into the semi-enclosed cavity surrounded by the shearing punch and the floating mandrel by shear deformation; Step 3: Use the floating mandrel or the lower ejector to eject the part, complete demoulding, and obtain the target part.

2. The plate forging method of the R-shaped fork ring part according to claim 1 is characterized in that: The inner wall of the necking extrusion punch has an angle with the axial direction, and the inner wall of the shearing punch also has an angle with the axial direction, and the angles of the two are equal.

3. The plate forging method of the R-shaped fork ring part according to claim 1, characterized in that: The upper end of the floating mandrel has the same angle as the inner wall of the necking extrusion punch.

4. The plate forging method of the R-shaped fork ring part according to claim 1, characterized in that: In the step 2, the shearing punch and the floating mandrel move downward synchronously.

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