A production method of aluminum-magnesium alloy cylindrical flange

Abstract

The present invention belongs to the technical field of aluminum-magnesium alloy flange production, and specifically relates to a production method for an aluminum-magnesium alloy cylindrical flange, comprising forging, punching and ring rolling performed in sequence, with a lever reaming process added between punching and ring rolling; a heated ring blank is sleeved on a reaming core rod and is directly below a forging die; a hydraulic press is started to forge the ring blank on the reaming core rod, and the ring blank is rotated multiple times during the forging process; compared with the prior art, the present invention (1) uses a forging die to forge the ring blank on the lever reaming core rod, so that the wall thickness of the ring blank is greatly reduced, thereby avoiding the sticking phenomenon of the roller occurring during the hot ring rolling process of the aluminum-magnesium alloy in the prior art; and (2) during the cold ring rolling process, the axis of the semi-finished product is vertical, thereby avoiding the deformation problem caused by the coupling effect of the ring blank's own gravity, statics, kinematics, dynamics and other factors when the vertical ring rolling machine is used for hot ring rolling in the prior art.

Description

Technical Field

[0001] The invention belongs to the technical field of aluminum-magnesium alloy cylindrical flange production, and in particular relates to a production method of an aluminum-magnesium alloy cylindrical flange. Background Art

[0002] Aluminum alloy flanges are generally produced by forging, punching, and ring rolling (hot rolling). Ring rolling, also known as ring rolling and hole expansion, is the process of sending the forged ring blank into the ring rolling machine under high temperature and repeatedly rolling the ring. During the ring rolling production, the wall thickness of the ring blank is reduced, the diameter is expanded, and the cross-sectional profile is formed.

[0003] The yield strength of aluminum alloy, especially aluminum-magnesium alloy, is much smaller than that of carbon steel, and the plasticity is strong. In the ring rolling (hot processing), it shows obvious characteristics of high viscosity and sticking to the roller. In the ring rolling process, the ring blank is easily deformed by the coupling of statics, kinematics, dynamics and other factors. Therefore, the operation of aluminum alloy flange ring rolling is difficult, and the precision of the ring blank is difficult to control. In addition, the outer diameter of large aluminum alloy forged flanges reaches 1800mm and the weight reaches more than 600 kilograms. In the production process, the wall thickness of the ring blank is small and the length is large, which exceeds the processing limit of the equipment. There is no mature experience to learn from in China.

[0004] With the construction of high-voltage and ultra-high-voltage projects in the country, the demand for aluminum-magnesium alloy flanges is increasing. It is particularly necessary to solve the above-mentioned problems in the production process of aluminum alloy flanges and meet market and customer needs. Summary of the invention

[0005] In view of the above problems, the present invention provides a method for producing an aluminum-magnesium alloy cylindrical flange.

[0006] In order to achieve the above object, the technical solution adopted by the present invention is: a production method of an aluminum-magnesium alloy cylindrical flange, comprising forging, punching and ring rolling in sequence, wherein a horse lever reaming process is added between the punching and ring rolling; the horse lever comprises a reaming mandrel and a horse frame;

[0007] Before the horse lever hole expansion begins, the forging die is installed on the lower end of the piston rod of the hydraulic press; at the same time, the horse lever is installed below the forging die; the heated annular blank is sleeved on the hole expansion mandrel and is located directly below the forging die;

[0008] During the horse lever reaming process, the hydraulic press is started, and the piston rod of the hydraulic press drives the forging die to forge the annular blank on the reaming core rod, and the annular blank is rotated multiple times during the forging process; during the forging process, the overall wall thickness of the annular blank is reduced and the diameter is increased, thereby obtaining a semi-finished product of an aluminum-magnesium alloy cylindrical flange.

[0009] Preferably, the ring rolling is to cold-roll a semi-finished product one to obtain a semi-finished product two of an aluminum-magnesium alloy cylindrical flange, and the axis of the semi-finished product one is vertical during the cold-rolling process.

[0010] Preferably, a stabilization annealing process is provided after the cold-rolled ring.

[0011] Preferably, the amount of wall thickness reduction of the ring blank in the horse bar hole expansion process is two to three times the amount of wall thickness reduction of the semi-finished product in the cold ring rolling process.

[0012] Preferably, during the forging process of the horse bar hole expansion, a robot is used to rotate the ring blank for multiple circles; the movement of the forging die includes downward pressing and return stroke, and during the return stroke, the robot clamps the ring blank and rotates it by a certain angle; when the ring blank rotates one circle, one circle of hole expansion is completed.

[0013] Preferably, during the forging process of the horse bar hole expansion, the initial forging temperature is 500-550°C, and the final forging temperature is 350-400°C.

[0014] Preferably, the cold-rolling of the semi-finished product 1 is completed by using a cold ring rolling machine, which includes a vertical rolling wheel, a core roller and a roundness roller.

[0015] Preferably, in the stabilization annealing step, an aluminum alloy heat treatment furnace is used to perform stabilization annealing on the semi-finished product 2.

[0016] Compared with the prior art, the advantages and positive effects of the present invention are:

[0017] (1) In the production method of the aluminum-magnesium alloy cylindrical flange of the present invention, a saddle hole expansion process is added between punching and ring rolling, and the wall thickness thinning amount of the ring blank in the saddle hole expansion process is much greater than the wall thickness thinning amount of the semi-finished product in the ring rolling process; the above technical solution uses a forging die to forge the ring blank on the saddle hole expansion mandrel, so that the wall thickness of the ring blank is greatly reduced, avoiding the sticking roller phenomenon that occurs in the aluminum-magnesium alloy hot rolling process in the prior art;

[0018] (2) The ring is cold rolled, and the amount of thinning of the wall thickness of the semi-finished product is small. The strength of the aluminum-magnesium alloy (at room temperature) during the cold rolling process of the above technical solution is greater than the strength of the aluminum-magnesium alloy (after heating) during hot rolling, and the aluminum-magnesium alloy is not prone to roller sticking during cold processing.

[0019] (3) The axis of the semi-finished product is vertical during the cold ring rolling process, which avoids the deformation problem of the ring blank caused by the coupling effect of its own gravity, statics, kinematics, dynamics and other factors when the vertical ring rolling machine is used in the prior art;

[0020] (4) A stabilization annealing process is provided after the cold-rolled ring to prevent the semi-finished product from softening due to aging, so that the mechanical properties of the cylindrical flange after the cold-rolled ring are stable. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] In order to more clearly illustrate the technical solution of the embodiment of the present invention, the following briefly introduces the drawings required for describing the embodiment. Figure 1 A diagram showing a production method for an aluminum-magnesium alloy cylindrical flange;

[0022] Figure 2 It is a schematic diagram of the production method of aluminum-magnesium alloy cylindrical flange before the start of the horse lever hole expansion;

[0023] Figure 3 It is a schematic diagram of the production method of aluminum-magnesium alloy cylindrical flange when the hole expansion of the lever is completed;

[0024] Figure 4 Schematic diagram of the cold-rolled ring in the production method of magnesium alloy cylindrical flange.

[0025] Description of reference numerals:

[0026] 1—forging die, 2—expanding mandrel, 3—horse frame, 4—manipulator, 5—core roller, 6—roller wheel. DETAILED DESCRIPTION

[0027] In order to more clearly understand the above-mentioned objects, features and advantages of the present invention, the present invention is further described below with reference to the accompanying drawings and embodiments.

[0028] In the following description, many specific details are set forth to facilitate a full understanding of the present invention. However, the present invention may also be implemented in other ways than those described herein. Therefore, the present invention is not limited to the specific embodiments of the following disclosure.

[0029] Example 1

[0030] The following is combined with Figure 1-4 The present invention is further described as follows: a method for producing an aluminum-magnesium alloy cylindrical flange, such as Figure 1 As shown, it includes forging, punching and ring rolling in sequence, and a lever hole expansion process is added between punching and ring rolling. The diameter of the aluminum-magnesium alloy cylindrical flange is 1000-2500mm.

[0031] like Figure 2 and 3 As shown, the horse lever includes a reaming core rod 2 and a horse frame 3.

[0032] like Figure 2As shown, before the horse bar reaming begins, the forging die 1 is installed on the lower end of the piston rod of the hydraulic press; at the same time, the horse bar is installed below the forging die 1; the heated annular blank is sleeved on the reaming core rod 2 and is directly below the forging die 1.

[0033] During the hole expansion process of the lever, the hydraulic press is started, and the piston rod of the hydraulic press drives the forging die 1 to forge the ring blank on the hole expansion mandrel 2, and the ring blank is rotated multiple times during the forging process; during the forging process, the overall wall thickness of the ring blank is reduced and the diameter is increased, and a semi-finished product of an aluminum-magnesium alloy cylindrical flange is obtained, such as Figure 3 shown.

[0034] like Figure 4 As shown, the ring rolling is to cold-roll the semi-finished product one to obtain the semi-finished product two of the aluminum-magnesium alloy cylindrical flange, and the axis of the semi-finished product one is vertical during the cold-rolling process.

[0035] The wall thickness of the ring blank used in this embodiment is 130 mm, and the wall thickness of the semi-finished product 2 after cold rolling is 10 mm.

[0036] After the cold-rolled ring, a stabilization annealing process is provided.

[0037] The wall thickness reduction of the ring blank in the process of horse bar expansion is twice that of the wall thickness reduction of semi-finished product 1 in the process of cold rolling ring. The wall thickness reduction of semi-finished product 1 in the cold rolling ring is 40mm (the wall thickness of semi-finished product 1 is about 50mm, and the wall thickness of semi-finished product 2 is 10mm); the wall thickness reduction of the ring blank in the process of horse bar expansion is 80mm (the wall thickness of semi-finished product 1 is about 50mm).

[0038] During the forging process of the horse bar hole expansion, the manipulator 4 is used to rotate the ring blank for multiple circles (four circles in this embodiment); the movement of the forging die 1 includes downward pressing and return stroke. During the return stroke, the manipulator 4 clamps the ring blank and rotates a certain angle; when the ring blank rotates one circle, one circle of hole expansion is completed.

[0039] During the forging process of the horse bar hole expansion, the initial forging temperature is 500-550℃, and the final forging temperature is 350-400℃.

[0040] like Figure 4 As described above, the cold ring rolling of the semi-finished product 1 is completed by using a cold ring rolling machine (such as the cold ring rolling machine in CN2267111Y), which includes a vertical rolling wheel 6, a core roller 5 and a roundness roller.

[0041] In the stabilization annealing process, the semi-finished product 2 is subjected to stabilization annealing (stabilization annealing temperature is about 150° C.) in an aluminum alloy heat treatment furnace.

[0042] Example 2

[0043] The difference between this embodiment and embodiment 1 is that the wall thickness reduction of the ring blank in the horse bar hole expansion process is three times the wall thickness reduction of the semi-finished product 1 in the cold rolling process. The wall thickness reduction of the semi-finished product 1 in the cold rolling process is 30 mm (the wall thickness of the semi-finished product 1 is about 40 mm, and the wall thickness of the semi-finished product 2 is 10 mm); the wall thickness reduction of the ring blank in the horse bar hole expansion process is 90 mm (the wall thickness of the semi-finished product 1 is about 40 mm).

[0044] In the stabilization annealing process, the semi-finished product 2 is subjected to stabilization annealing in an aluminum alloy continuous heat treatment furnace.

[0045] The above are only preferred embodiments of the present invention and are not intended to limit the present invention in other forms. Any technician familiar with the profession may use the technical contents disclosed above to change or modify them into equivalent embodiments with equivalent changes and apply them to other fields. However, any simple modification or equivalent change made to the above embodiments based on the technical essence of the present invention without departing from the technical solution of the present invention still falls within the protection scope of the technical solution of the present invention.

Claims

1. A method for producing an aluminum-magnesium alloy cylindrical flange, comprising forging, punching and ring rolling in sequence, characterized in that: A horse bar hole expansion process is added between the punching and the ring rolling; the horse bar comprises a hole expansion core rod (2) and a horse frame (3); Before the horse lever hole expansion begins, the forging die (1) is installed at the lower end of the piston rod of the hydraulic press; at the same time, the horse lever is installed below the forging die (1); the heated annular blank is sleeved on the hole expansion mandrel (2) and is located directly below the forging die (1); During the horse lever hole expansion process, the hydraulic press is started, and the piston rod of the hydraulic press drives the forging die (1) to forge the annular blank on the hole expansion core rod (2), and the annular blank is rotated multiple times during the forging process; during the forging process, the overall wall thickness of the annular blank is reduced and the diameter is increased, thereby obtaining a semi-finished product of an aluminum-magnesium alloy cylindrical flange; The ring rolling is to cold-roll the semi-finished product 1 to obtain the semi-finished product 2 of the aluminum-magnesium alloy cylindrical flange, and the axis of the semi-finished product 1 is vertical during the cold-rolling process; The amount of wall thickness reduction of the ring blank in the horse bar hole expansion process is two to three times the amount of wall thickness reduction of the semi-finished product in the cold ring rolling process.

2. The method for producing an aluminum-magnesium alloy cylindrical flange according to claim 1, characterized in that: The cold-rolled ring is then subjected to a stabilization annealing process.

3. The method for producing an aluminum-magnesium alloy cylindrical flange according to claim 1, characterized in that: During the forging process of the horse bar hole expansion, the manipulator (4) is used to rotate the annular blank for multiple turns; the movement of the forging die (1) includes downward pressing and return stroke, and during the return stroke, the manipulator (4) clamps the annular blank and rotates it by a certain angle; when the annular blank rotates one circle, one circle of hole expansion is completed.

4. The method for producing an aluminum-magnesium alloy cylindrical flange according to claim 3, characterized in that: During the forging process of the horse bar hole expansion, the initial forging temperature is 500-550°C, and the final forging temperature is 350-400°C.

5. The method for producing an aluminum-magnesium alloy cylindrical flange according to claim 1, characterized in that: The cold ring rolling of the semi-finished product 1 is completed by using a cold ring rolling machine, which includes a vertical rolling wheel (6), a core roller (5) and a roundness roller.

6. The method for producing an aluminum-magnesium alloy cylindrical flange according to claim 2, characterized in that: In the stabilization annealing process, an aluminum alloy heat treatment furnace is used to perform stabilization annealing on the semi-finished product 2.

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