Chamfering method for T-shaped undercarriage forge piece rough blank

Abstract

The invention relates to the technical field of forging and pressing, in particular to a T-shaped undercarriage forge piece rough blank chamfering method. The method comprises the steps that S1, a bar is placed in a heating furnace to be heated, square drawing is conducted on the bar, the bar is divided into a head part and a rod part, and the head part and the rod part are drawn out; upsetting the head part after drawing out; s2, the rod part is drawn out, the edges of the rod part are chamfered after drawing out, and a blank is formed; s3, the blank is placed in a chamfering tool, a rod part is clamped through a material clamping machine, a high-speed forging machine drives an upper flat anvil to press down, and a chamfer is formed on the edge; and S4, the blank is rotated by 180 degrees around the axis of the rod part, the rod part is clamped through a material clamping machine, the high-speed forging machine drives the upper flat anvil to press down, and chamfers are formed on the other set of edges. According to the invention, after the blank is prepared, the blank is placed in the chamfering tool and is pressed and chamfered by using the upper flat anvil, so that the production continuity is guaranteed, the polishing amount of the rough blank is reduced, the machining procedures of the rough blank are reduced, the production and manufacturing cost is reduced, and the production efficiency of products is improved.

Description

Technical Field

[0001] The invention relates to the technical field of forging, in particular to a method for chamfering a T-shaped landing gear forging blank. Background Art

[0002] The landing gear piston rod is one of the core components of the aircraft landing gear. As an important safety function component of the aircraft, it is an important support system for the aircraft takeoff, landing, ground taxiing and parking, and is the main load-bearing component of the aircraft. Through the piston movement of the landing gear piston rod and the outer cylinder, the impact energy formed by the aircraft and the ground during landing and taxiing is absorbed and dissipated, ensuring the safety of the aircraft during ground movement.

[0003] The structure of the landing gear piston rod blank is as follows Figure 1 As shown, it includes a head and a rod connected to the lower surface of the head, and the whole is in a "T" shape. At present, landing gear piston rods are mostly made of ultra-high strength A-100 steel. Since A-100 steel is more sensitive to forging times, the die forging process is required to be completed within 1 fire, which puts higher requirements on the quality of the rough billet. When the existing rough billet is forged, the rod can be chamfered by forging, but the four edges of the head along the length direction cannot be chamfered by forging due to interference from the rod. The head of the existing rough billet after forging is as follows Figure 3 As shown, there are mainly two existing edge chamfering technology paths.

[0004] The first method is: after the blank is manufactured and cooled, the "manual grinding and chamfering" method is used to grind the edge area of ​​the blank head with a grinding wheel to achieve a smooth transition of R ≥ 20mm for the blank, ensuring that the forging will not form folding and pinching defects during final forging. However, this method has the following defects: if the grinding R is too small, it will not prevent folding, and the manual grinding amount is large when the grinding R angle meets the requirements. In addition, each piece needs to be inspected by an inspector to carefully verify the R value to confirm that the grinding meets the requirements, and the grinding consistency is poor.

[0005] The second method is to use the "annealing + machining chamfering" method. Annealing takes 3 days to reduce the hardness of A-100 steel, and then the head edge is chamfered by machining (such as milling) to achieve a smooth transition of the rough head. However, this method has the disadvantages of long production cycle and high production cost. Summary of the invention

[0006] The technical problem to be solved by the present invention is to provide a T-shaped landing gear forging blank chamfering method for chamfering the edge of the head.

[0007] The technical solution adopted by the present invention to solve the technical problem is a T-shaped landing gear forging blank chamfering method, comprising the following steps:

[0008] S1: placing a bar in a heating furnace and heating it until the core reaches the temperature, square-drawing the bar, dividing the bar into a head and a stem after square-drawing, and lengthening the head and the stem respectively; placing the stem in a forming hole on a drain plate after lengthening and upsetting the head, and square-drawing and trimming the head after upsetting, wherein the lower surface of the head includes a first edge and a second edge along the length direction of the head, and the upper surface of the head includes a third edge and a fourth edge along the length direction of the head; the first edge is opposite to the third edge, and the second edge is opposite to the fourth edge;

[0009] S2: The rod is stretched and then the edges of the rod are chamfered to form a blank;

[0010] S3: placing the blank in a chamfering tool, wherein the upper surface of the chamfering tool is provided with a first groove for placing the connection between the head and the rod and a second groove for placing the rod, the bottom surfaces of the first groove and the second groove are both inclined surfaces with smooth transition, the connection between the head and the rod is placed in the first groove, and the rod is placed in the second groove, at which time the rod is in an inclined state, so that the first edge on the lower surface of the head is in close contact with the upper surface of the chamfering tool, the angle formed by the plane formed by the first edge and the third edge and the upper surface of the chamfering tool is 85° to 95°, the rod is clamped by a clamping machine, the upper flat anvil on the fast forging machine contacts the third edge, and the fast forging machine drives the upper flat anvil to press down, so as to form chamfers on the first edge and the third edge;

[0011] S4: Rotate the blank 180° around the axis of the rod, so that the second edge on the lower surface of the head is in close contact with the upper surface of the chamfering tool, and the angle formed by the plane formed by the second edge and the fourth edge and the upper surface of the chamfering tool is 85° to 95°. Use a clamp to clamp the rod, and the upper anvil on the fast forging machine contacts the fourth edge. The fast forging machine drives the upper anvil to press down to form chamfers on the second edge and the fourth edge.

[0012] Furthermore, a first arc-shaped avoidance surface is provided at the connection between the side wall of the first groove and the upper surface of the chamfering tooling, and a second arc-shaped avoidance surface is provided at the connection between the side wall of the second groove and the upper surface of the chamfering tooling.

[0013] Furthermore, the width of the first groove is greater than the width of the connection between the rod and the head; the width of the second groove is greater than the width of the rod.

[0014] Further, in step S3, the angle formed by the plane formed by the first edge and the third edge and the upper surface of the chamfering tool is 90°; in step S4, the angle formed by the plane formed by the second edge and the fourth edge and the upper surface of the chamfering tool is 90°.

[0015] The beneficial effects of the present invention are as follows: after the blank is prepared, the blank is placed in a chamfering tool and the chamfering is pressed using an upper flat anvil, thereby ensuring the continuity of production, reducing the amount of grinding of the blank, reducing the annealing process, reducing the processing process of the blank, reducing the production cost, and improving product production efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 It is a structural schematic diagram of a landing gear piston rod blank;

[0017] Figure 2 Schematic diagram of the intermediate blank formed by the bar material through step S1 into the head and the stem;

[0018] Figure 3 This is a schematic diagram of the blank after the rod is drawn and chamfered;

[0019] Figure 4 It is a schematic diagram of the edge identification of the blank;

[0020] Figure 5 It is a schematic diagram of the chamfering tooling;

[0021] Figure 6 It is a schematic diagram of the blank being placed on the chamfering tooling.

[0022] Figure markings: 1-head; 2-rod; 3-first edge; 4-second edge; 5-third edge; 6-fourth edge; 7-chamfering tool; 8-first groove; 9-second groove; 10-first avoidance surface, 11-second avoidance surface; 12-upper flat anvil. DETAILED DESCRIPTION

[0023] Embodiments of the present invention are described in detail below, examples of which are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present invention, and cannot be understood as limiting the present invention.

[0024] like Figure 1-Figure 6 As shown, the present invention provides a T-shaped landing gear forging blank chamfering method, comprising the following steps:

[0025] S1: placing a bar in a heating furnace and heating it until the core reaches the temperature, square drawing the bar, dividing the bar into a head 1 and a rod 2 after square drawing, and respectively lengthening the head 1 and the rod 2; placing the rod 2 in a forming hole on a drain plate after lengthening and upsetting the head 1, and square drawing and trimming the head 1 after upsetting, wherein the lower surface of the head 1 includes a first edge 3 and a second edge 4 along the length direction of the head 1, and the upper surface of the head 1 includes a third edge 5 and a fourth edge 6 along the length direction of the head 1; The first edge 3 is opposite to the third edge 5, and the second edge 4 is opposite to the fourth edge 6; wherein the cross-sectional dimension of the stem 2 is smaller than the cross-sectional dimension of the head 1, and the projection of the stem 2 on the horizontal plane is located within the projection of the head 1 on the horizontal plane; the cross-sectional dimension of the forming hole on the drain disk is larger than the cross-sectional dimension of the stem 2 and smaller than the cross-sectional dimension of the stem 2, and a rounded transition is provided between the forming hole of the drain disk and the upper surface of the drain disk, and the head 1 is upset by pressing down with a press, and then the head 1 is squared and trimmed into a rectangle. The first edge 3 and the third edge 5 are diagonally opposite to each other, and the second edge 4 and the fourth edge 6 are also diagonally opposite to each other.

[0026] S2: The rod 2 is stretched and then the edges of the rod 2 are chamfered to form a blank; see Figure 4 The upper and lower flat anvils can be used to lengthen the rod 2, and then rotate it 45° around the axis of the rod 2 so that the edge of the rod 2 is opposite to the lower surface of the flat anvil. Pressing the flat anvil down can achieve the chamfering of the edge of the rod 2.

[0027] S3: placing the blank in the chamfering fixture 7, the upper surface of the chamfering fixture 7 is provided with a first groove 8 for placing the connection between the head 1 and the rod 2 and a second groove 9 for placing the rod 2, the bottom surfaces of the first groove 8 and the second groove 9 are both inclined surfaces with smooth transition, the connection between the head 1 and the rod 2 is placed in the first groove 8, and the rod 2 is placed in the second groove 9, at this time the rod 2 is in an inclined state, so that the first edge 3 on the lower surface of the head 1 is in close contact with the upper surface of the chamfering fixture 7, the angle formed by the plane formed by the first edge 3 and the third edge 5 and the upper surface of the chamfering fixture 7 is 85° to 95°, the rod 2 is clamped by a clamping machine, the upper flat anvil 12 on the fast forging machine contacts the third edge 5, the fast forging machine drives the upper flat anvil 12 to press down, and chamfers are formed on the first edge 3 and the third edge 5; wherein, see Figure 5 and Figure 6, the chamfering tool 7 is placed on the working table of the fast forging machine, the first groove 8 and the second groove 9 are formed by die forging, the second groove 9 can be a through groove, that is, the second groove 9 extends to the side of the chamfering tool 7, the depth of the second groove 9 is greater than the depth of the first groove 8, and the connecting surfaces of the first groove 8 and the second groove 9 are smoothly transitioned; the width of the first groove 8 is greater than the width of the connection between the rod 2 and the head 1; the width of the second groove 9 is greater than the width of the rod 2; the connection between the head 1 and the rod 2 is placed in the first groove 8, the rod 2 is placed in the second groove 9, and the first When the edge 3 is in close contact with the upper surface of the chamfering tool 7, there is a gap between the connection between the head 1 and the rod 2 and the side and bottom of the first groove 8, and there is also a gap between the rod 2 and the side and bottom of the second groove 9, and this gap is greater than the pressing amount of the upper flat anvil 12; the angle formed by the plane formed by the first edge 3 and the third edge 5 and the upper surface of the chamfering tool 7 is 85° to 95°, and the angle formed by the plane formed by the first edge 3 and the third edge 5 and the upper surface of the chamfering tool 7 is preferably 90°, so that the pressing amount can be better calculated by the designed chamfering size of the edge of the head 1, such as Figure 1 As shown, the chamfer size of the edge of the head 1 is 20mm*45°, so the pressing amount is 20√2mm. In the actual manufacturing process, the actual pressing amount will be 2-5mm greater than the theoretical pressing amount.

[0028] S4: Rotate the blank 180° around the axis of the rod 2, so that the second edge 4 on the lower surface of the head 1 is in close contact with the upper surface of the chamfering tool 7, and the angle formed by the plane formed by the second edge 4 and the fourth edge 6 and the upper surface of the chamfering tool 7 is 85° to 95°, and the rod 2 is clamped by a clamping machine, and the upper flat anvil 12 on the fast forging machine contacts the fourth edge 6, and the fast forging machine drives the upper flat anvil 12 to press down, and chamfers are formed on the second edge 4 and the fourth edge 6. Preferably, the angle formed by the plane formed by the second edge 4 and the fourth edge 6 and the upper surface of the chamfering tool 7 is 90°.

[0029] In order to prevent the connection between the head 1 and the stem 2 from interfering with the side wall of the first groove 8 and the side wall of the stem 2 and the second groove 9 when the upper flat anvil 12 is pressed down, further see Figure 5 A first arc-shaped avoidance surface 10 is provided at the connection between the side wall of the first groove 8 and the upper surface of the chamfering tool 7, and a second arc-shaped avoidance surface 11 is provided at the connection between the side wall of the second groove 9 and the upper surface of the chamfering tool 7.

[0030] The embodiments of this specific implementation method are all preferred embodiments of the present invention, and are not intended to limit the protection scope of the present invention. Therefore, any equivalent changes made based on the structure, shape, and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. A method for chamfering a T-shaped landing gear forging blank, characterized in that: The following steps are included: S1: placing a bar in a heating furnace and heating it until the core reaches the temperature, then square drawing the bar, dividing the bar into a head (1) and a stem (2) after square drawing, and respectively lengthening the head (1) and the stem (2); after lengthening, placing the stem (2) in a forming hole on a drain plate and upsetting the head (1); after upsetting, square drawing and trimming the head (1); the lower surface of the head (1) includes a first edge (3) and a second edge (4) along the length direction of the head (1); the upper surface of the head (1) includes a third edge (5) and a fourth edge (6) along the length direction of the head (1); the first edge (3) is opposite to the third edge (5), and the second edge (4) is opposite to the fourth edge (6); S2: The rod (2) is stretched, and after the stretching, the edges of the rod (2) are chamfered to form a blank; S3: The blank is placed in a chamfering tool (7), wherein the upper surface of the chamfering tool (7) is provided with a first groove (8) for placing the connection between the head (1) and the rod (2) and a second groove (9) for placing the rod (2), wherein the bottom surfaces of the first groove (8) and the second groove (9) are both inclined surfaces with smooth transitions, the connection between the head (1) and the rod (2) is placed in the first groove (8), and the rod (2) is placed in the second groove (9), at which time the rod (2 ) is in an inclined state, so that the first edge (3) on the lower surface of the head (1) is in close contact with the upper surface of the chamfering tool (7), and the angle formed by the plane formed by the first edge (3) and the third edge (5) and the upper surface of the chamfering tool (7) is 85° to 95°, the rod (2) is clamped by a clamping machine, the upper flat anvil (12) on the fast forging machine contacts the third edge (5), and the fast forging machine drives the upper flat anvil (12) to press down, so as to form chamfers on the first edge (3) and the third edge (5); S4: The blank is rotated 180° around the axis of the rod (2) so that the second edge (4) on the lower surface of the head (1) is in close contact with the upper surface of the chamfering tool (7), and the angle formed by the plane formed by the second edge (4) and the fourth edge (6) and the upper surface of the chamfering tool (7) is 85° to 95°. The rod (2) is clamped by a clamping machine, and the upper flat anvil (12) on the fast forging machine contacts the fourth edge (6). The fast forging machine drives the upper flat anvil (12) to press down, thereby forming chamfers on the second edge (4) and the fourth edge (6).

2. A T-shaped landing gear forging blank chamfering method as claimed in claim 1, characterized in that: A first arc-shaped avoidance surface (10) is provided at the connection between the side wall of the first groove (8) and the upper surface of the chamfering tool (7), and a second arc-shaped avoidance surface (11) is provided at the connection between the side wall of the second groove (9) and the upper surface of the chamfering tool (7).

3. A T-shaped landing gear forging blank chamfering method as claimed in claim 2, characterized in that: The width of the first groove (8) is greater than the width of the connection between the rod (2) and the head (1); the width of the second groove (9) is greater than the width of the rod (2).

4. A T-shaped landing gear forging blank chamfering method as claimed in claim 1, characterized in that: In step S3, the angle formed by the plane formed by the first edge (3) and the third edge (5) and the upper surface of the chamfering tool (7) is 90°; in step S4, the angle formed by the plane formed by the second edge (4) and the fourth edge (6) and the upper surface of the chamfering tool (7) is 90°.

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