Spinning forming method for aluminum alloy small-half-cone-angle cone-barrel-shaped structural part

Abstract

The invention discloses a spinning forming method for an aluminum alloy small-half-cone-angle conical cylindrical structural part, belongs to the technical field of material processing, and aims to solve the problems that in the prior art, a workpiece has weld joints, the overall performance is affected, the number of processing passes is large, and the forming force needed by equipment is large, save the manufacturing cost and reduce manpower and material resource consumption. The spinning forming method disclosed by the invention is realized in a manner of preparing a blank, debugging a spinning device, strongly spinning and machining. The process problems that the aluminum alloy small-half-cone-angle conical cylindrical structural part is large in wall thickness reduction rate, difficult to form, difficult in precision control and large in equipment forming force are solved. The processing efficiency and the material utilization rate are improved, and the process labor intensity is reduced. The defects of high raw material consumption, unstable product mechanical property and the like are greatly improved, and the problems of unstable product quality and the like in the previous production process are fundamentally avoided.

Description

Technical Field

[0001] The present invention belongs to the technical field of material processing, and particularly relates to a spinning forming method for an aluminum alloy conical barrel-shaped structural member with a small half-cone angle. Background Art

[0002] Existing forming methods for conical cylinders include methods such as sheet metal power spinning, die extrusion forming, and sheet metal rolling welding forming. Among them, rolling welding forming is prone to defects such as pores, cracks, and slag inclusions at the weld. The appearance of the weld reduces the overall circumferential performance. Die extrusion forming requires multiple reverse extrusions to form a straight cylinder, and then a conical cylinder is formed through necking or flaring extrusion. The forming is complex and the precision control is not high. Finally, necking or flaring extrusion requires a suitable reduction coefficient, and the size range of the finally formed conical part is narrow. Sheet metal power spinning cannot form a conical barrel with a small half-cone angle in one step. Moreover, through the blank wall thickness calculation formula in power spinning, it can be seen that such components require thick sheets to be formed, which requires a high spinning force for the equipment. Summary of the Invention

[0003] The purpose of the present invention is to propose a spinning forming method for an aluminum alloy conical barrel-shaped structural member with a small half-cone angle, to solve the problems existing in the prior art such as the workpiece having a weld, affecting the overall performance, having multiple processing steps, and the forming force required by the equipment being large, saving manufacturing costs, and reducing the consumption of manpower and material resources.

[0004] To achieve the above purpose, a spinning forming method for an aluminum alloy conical barrel-shaped structural member with a small half-cone angle of the present invention includes the following steps: Step 1: Determine the process route. Since the final component is a rotating body with a small half-cone angle and a straight generatrix, a tubular blank is used. Calculate the blank according to the dimensions of the finally formed part, and allocate the spinning stroke n and the roller path; Step 2: Prepare the blank. The tail of the blank is fixed to the die through a circular chuck or bolt for positioning and torque transmission. To achieve the maximum plasticity of the blank, the blank state is an annealed state, and the debris on the blank surface is removed and the defects are polished; Step 3: Debug the spinning device and clamp the blank prepared in Step 2. Use a numerically controlled power spinning machine to clamp the spinning die, fix and position the tail of the tubular blank to the die through a chuck or bolt, and select a suitable roller; Step 4: Perform spinning with a numerical control program. The roller performs multi-stroke spinning on the blank according to the trajectory determined in Step 1, and the range of the roller R is between 1 and 2 times the thickness of the blank; Step 5: Demold the spun part obtained in Step 4; Step 6: Machining. Machine the workpiece annealed in Step 6 to the final dimensions; The spinning stroke n described in Step 1 is specifically calculated based on the radius difference between the large and small ends of the final spun part. The radius reduction amount of the small end of the blank in each stroke is 10 - 40 mm, and the total reduction amount reaches the radius difference between the large and small ends of the final spun part after n strokes.

[0005] The spinning wheel trajectory described in Step 1 is forward and reverse combined spinning, and the forward stroke and the reverse stroke can be interspersed.

[0006] In Step 3, a numerically controlled open spinning press is used to clamp the spinning die. After clamping, a dial indicator is used to correct the runout of the spinning die, so that the runout of the die conical surface is less than or equal to 0.1 mm.

[0007] During the spinning process in Step 4, the ratio range of the spindle speed to the feed speed of the spinning wheel of the numerically controlled open spinning press is between 0.7 and 1.5.

[0008] The beneficial effects of the present invention are as follows: The spinning forming method of an aluminum alloy small semi-cone angle conical barrel-shaped structural part of the present invention solves the problems of large wall thickness reduction rate, difficult forming, many passes, and large forming force of the conical barrel-shaped structure. By using an optimized spinning process and blank, one-pass spinning forming of the aluminum alloy small semi-cone angle conical barrel-shaped structure is realized. Compared with the previous method of forming such components by rolling and welding, this method greatly saves the mold manufacturing cost and shortens the product processing cycle. It accumulates valuable experience for the forming of large-diameter thick-wall material special-shaped structures and lays a foundation for accelerating the realization of engineering applications. BRIEF DESCRIPTION OF THE DRAWINGS

[0009] Figure 1 It is a schematic diagram of the assembly of the blank, spinning wheel, and die of the spinning forming method of an aluminum alloy small semi-cone angle conical barrel-shaped structural part of the present invention; Figure 2 It is a schematic diagram of the spinning pass distribution in the spinning forming method of an aluminum alloy small semi-cone angle conical barrel-shaped structural part of the present invention; Wherein: 1. Die, 2. Fixed bolt, 3. Blank, 4. Spinning wheel, 5. Final spun part EMBODIMENTS

[0010] The following further describes the embodiments of the present invention with reference to the drawings. EXAMPLE

[0011] The thick-walled conical barrel-shaped structure referred to in the present invention refers to a structure with a circular opening end and bottom end and a conical surface in the middle, and the accuracy requirement of the middle conical surface is high.

[0012] A spinning forming method of an aluminum alloy small semi-cone angle conical barrel-shaped structural part of the present invention includes the following steps: Step 1: Determine the process route. Since the final component is a solid of revolution with a small half-cone angle and a straight generatrix, a tubular blank is used. Calculate the blank according to the dimensions of the final formed part, and allocate the spinning stroke n and the roller path; Step 2: Prepare the blank. The tail of the blank is fixed to the die through a circular chuck or bolts for positioning and torque transmission. To achieve the maximum plasticity of the blank, the blank state is annealed. Remove debris from the blank surface and grind the defects; Step 3: Debug the spinning device and clamp the blank prepared in Step 2. Use a CNC power spinning machine to clamp the spinning die, fix and position the tail of the tubular blank to the die through a chuck or bolts, and select a suitable roller; Step 4: Perform spinning with the CNC program. The roller performs multi-stroke spinning on the blank according to the trajectory determined in Step 1, and the forward and reverse strokes are alternated; Step 5: Demold the spun part obtained in Step 4; Step 6: Machining. Machine the workpiece annealed in Step 6 to the final dimensions; The specific allocation of the spinning stroke n and the roller path described in Step 1 is as follows: See Figure 1 - Figure 2 , ensure that the lengths of the blank and the spun part are equal in the radial direction. The stroke allocation is as follows: ensure that the downward displacement h length of a single stroke is 10 - 40 mm, and the total downward displacement H is reached after n forward and reverse strokes of spinning.

[0013] The surface treatment of the blank described in Step 2 is to grind the blank surface, and there are no scratches on the surface after grinding; The specific fixation and positioning of the tail of the tubular blank to the die through a chuck or bolts described in Step 3 is: see Figure 1 , use a multi-jaw chuck or the screw nut shown in the figure to fix the blank to the die with the figure as the reference.

[0014] After clamping the spinning die in Step 3, use a dial indicator to correct the runout of the spinning die, so that the runout of the die conical surface is less than or equal to 0.1 mm.

[0015] The selection of a suitable roller described in Step 3: Specifically, the range of the roller R is between 1 and 2 times the wall thickness of the blank.

[0016] The forward and reverse strokes described in Step 4 are alternated, see Figure 2 , and both forward spinning and reverse spinning exist simultaneously during the spinning process.

[0017] During the spinning process described in Step 4, the ratio of the spindle speed to the feed speed is in the range of 0.7 - 2.

Claims

1. A spinning forming method for an aluminum alloy conical barrel-shaped structural member with a small half-cone angle, characterized in that, It includes the following steps: Step 1: Determine the process route. Since the final component is a solid of revolution with a small half-cone angle and a straight generatrix, a tubular blank is used. Calculate the blank according to the dimensions of the final formed part, and allocate the spinning stroke n and the roller path; Step 2: Prepare the blank. The tail of the blank is fixed to the die through a circular chuck or bolts for positioning and torque transmission. To achieve the maximum plasticity of the blank, the blank state is annealed. Remove debris from the blank surface and grind the defects; Step 3: Debug the spinning device and clamp the blank prepared in Step 2. Use a CNC power spinning machine to clamp the spinning die. Fix and position the tail of the tubular blank to the die through a chuck or bolts, and select a suitable roller; Step 4: Perform spinning with a CNC program. The roller performs multi-stroke spinning on the blank according to the trajectory determined in Step 1. The range of roller R is between 1 and 2 times the thickness of the blank; Step 5: Demold the spun part obtained in Step 4; Step 6: Machining. Machine the workpiece annealed in Step 6 to the final dimensions.

2. The spinning forming method for an aluminum alloy conical barrel-shaped structural member with a small half-cone angle according to claim 1, characterized in that, The specific allocation of the spinning stroke n and the roller path described in Step 1 is as follows: Ensure that the lengths of the blank and the spun part are equal in the radial direction. The spinning stroke is allocated as follows: ensure that the downward displacement h per single stroke is 10 - 40 mm, and the total downward displacement H is reached after n forward and reverse strokes of spinning.

3. The spinning forming method for a 5A06 aluminum alloy conical barrel-shaped structure according to claim 1, characterized in that, The specific surface treatment of the blank described in Step 2 is to grind the blank surface, and there are no scratches on the surface after grinding.

4. The spinning forming method for a 5A06 aluminum alloy conical barrel-shaped structure according to claim 1, characterized in that, The specific fixation and positioning of the tail of the tubular blank to the die described in Step 3 by using a chuck or bolts is as follows: Use a multi-jaw chuck or the screw and nut shown in the figure to fix the blank to the die with the figure as the reference.

5. The spinning forming method for a 5A06 aluminum alloy conical barrel-shaped structure according to claim 1, characterized in that, For the clamping of the spinning die described in Step 3, after clamping, use a dial indicator to correct the runout of the spinning die, so that the runout of the die cone surface of the spinning die is less than or equal to 0.1 mm.

6. The spinning forming method for a 5A06 aluminum alloy conical barrel-shaped structure according to claim 1, characterized in that, The selection of a suitable roller described in Step 3 is specifically as follows: The range of roller R is between 1 and 2 times the wall thickness of the blank.

7. The spinning forming method for a 5A06 aluminum alloy conical barrel-shaped structure according to claim 1, characterized in that, The forward and reverse strokes described in Step 4 are alternated. See Figure 2. Both forward spinning and reverse spinning occur during the spinning process.

8. The spinning forming method for a 5A06 aluminum alloy conical barrel-shaped structure according to claim 1, characterized in that, During the spinning process described in Step 4, the ratio of the spindle speed to the feed speed is within the range of 0.7 - 2.

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