Method for collecting a point of a switch

Abstract

The present application relates to the technical field of switch rail processing, and particularly discloses a method for material gathering of a heel end of a switch rail, which comprises the following steps: clamping and fixing the clamping area of a blank, and placing the material gathering area of the blank into different die bores with different cross-sectional areas; segmentally heating the material gathering area of the blank; and segmentally upsetting and extruding the material gathering area by a die punch according to different material gathering ratios of different segments and lengths of the different segments. The method for material gathering of the heel end of the switch rail produces a deformation condition that is more favorable to the material gathering of the blank near the transition area of the heel end of the switch rail, thereby ensuring that the blank in the material gathering area obtains a good material gathering effect, realizing small-scale material gathering in the forming area of the heel end of the switch rail, and moderately adjusting the shape of the heel end, which is more convenient for subsequent forging.

Description

Technical Field

[0001] This invention relates to the field of turnout switch rail processing technology, and in particular to a method for assembling material at the heel end of the switch rail. Background Technology

[0002] The switch rail heel is the end where the switch rail connects to the guide curve rail. Since the switch rail profile is usually different from the guide curve rail, the switch rail heel needs to be modified through forging. When the cross-sectional area of ​​the switch rail has a large margin compared to the guide curve rail, the switch rail heel can be forged to obtain a suitable heel profile. When the cross-sectional area of ​​the switch rail is similar to or smaller than that of the guide curve rail, direct forging will result in a defect of insufficient material at the heel, a problem particularly prominent in the transition section. Therefore, in such cases, it is usually necessary to first aggregate the material at the heel before forging. During the aggregation process, the aggregation at the heel is not uniform. When the heel length is large (e.g., greater than 700 mm) and the aggregation ratio (the ratio of the switch rail cross-sectional area after aggregation to the switch rail cross-sectional area before aggregation) is small (e.g., less than 15%), due to the end effect, the billet near the heel end is upset first, the aggregation effect is more significant, and the die cavity near the heel end is filled early in the forming process. Due to the friction between the deformed metal and the die cavity sidewall, the forming force will increase sharply, causing the punch to be unable to advance further. As a result of material accumulation, the end of the heel has a large material accumulation ratio, while the part near the transition section has a very small material accumulation ratio, which cannot meet the needs of subsequent heel forging. Summary of the Invention

[0003] To address the technical problems in the prior art, this invention provides a method for material gathering at the heel end of a rail, which ensures that the billet in the gathering zone achieves good material gathering effect, realizes small-scale material gathering in the forming zone of the rail heel end, and appropriately adjusts the shape of the heel end, making it easier for subsequent forging.

[0004] A method for agglomerating the tip of a switch rail, the method comprising,

[0005] S1, clamp and fix the clamping area of ​​the billet, and place the aggregated parts of the billet into the mold cavity of different cross-sectional areas in sections;

[0006] S2: The material accumulation zone of the billet is heated in sections;

[0007] S3: The die punch performs segmented upsetting processing on the aggregate zone according to the aggregate ratio and length of the different aggregate zones.

[0008] Furthermore, the material aggregation zone is divided into a large material aggregation zone and a small material aggregation zone according to different material aggregation ratios. The large material aggregation zone is located at one end close to the clamping zone of the billet, while the small material aggregation zone is located at one end far from the clamping zone of the billet. The billet heating temperature in the large material aggregation zone is higher than that in the small material aggregation zone, and the material aggregation ratio in the large material aggregation zone is higher than that in the small material aggregation zone.

[0009] Furthermore, the heating temperature of the forging billet in the large aggregate zone is determined based on the initial forging temperature of the billet material, while the heating temperature of the forging billet in the small aggregate zone is 50℃-100℃ lower than that in the large aggregate zone.

[0010] Furthermore, the large material gathering area is divided into a switch rail heel end transition area and a switch rail heel end forming area according to different processing areas. The switch rail heel end transition area is located at one end close to the clamping area of ​​the blank, and the switch rail heel end forming area is located at the other end away from the clamping area of ​​the blank. The length of the large material gathering area is not less than the sum of the length of the switch rail heel end transition area and half the length of the switch rail heel end forming area.

[0011] Furthermore, the transition zone and the forming zone of the switch rail heel are connected by a G1 curved surface, the length of which is 1 / 10 of the total length of the material gathering zone.

[0012] Furthermore, the shape of the die punch is consistent with the cross-sectional shape of the blank, and the formula for calculating the working stroke S of the die punch is:

[0013] S=(C-1)*L*K

[0014] Where C represents the aggregate ratio, which is the ratio of the cross-sectional area of ​​the aggregated zone after aggregate formation to the cross-sectional area of ​​the aggregated zone before aggregate formation; L represents the length of the aggregated zone segments with different aggregate ratios; and K represents the stroke coefficient, with a value ranging from 1 to 1.15.

[0015] Furthermore, the cross-sectional reference shape of the mold cavity in the small aggregate zone is obtained by uniformly offsetting the blank shape outwards, and the magnitude of the offset is determined by the aggregate ratio of the small aggregate zone.

[0016] Furthermore, the shape of the mold cavity bottom of the small material gathering area is obtained by modifying the cross-sectional reference shape of the mold cavity of the small material gathering area. The length of the long limb of the mold cavity of the small material gathering area is the length after the reference size of the mold cavity of the small material gathering area is offset inward by 1-2 times, and the length of the short limb of the mold cavity of the small material gathering area is the length after the reference size of the mold cavity of the small material gathering area is offset outward by 1 time.

[0017] Furthermore, the reference shape of the mold cavity cross-section in the large material accumulation zone is obtained by uniformly offsetting the cross-sectional shape of the mold cavity in the small material accumulation zone outward by 1-2mm.

[0018] Furthermore, the shape of the mold cavity bottom of the large material gathering area is obtained by modifying the cross-sectional reference shape of the mold cavity of the large material gathering area. The length of the long limb of the mold cavity of the large material gathering area is the length after offsetting the reference size of the mold cavity of the large material gathering area inward by 1-2 times, and the length of the short limb of the mold cavity of the large material gathering area is the length after offsetting the reference size of the mold cavity of the large material gathering area outward by 1 time.

[0019] The present invention provides a method for accumulating material at the heel end of a switch rail. By using segmented heating and segmented accumulating die cavities with different reference sizes, deformation conditions are generated that are more favorable for accumulating material in the portion of the billet near the transition zone of the switch rail heel end. This ensures that the portion of the billet in the accumulating zone obtains a good accumulating effect, achieves small-scale accumulating of material in the forming zone of the switch rail heel end, and at the same time, appropriately adjusts the shape of the heel end, making it easier for subsequent forging. Attached Figure Description

[0020] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0021] Figure 1 This is a flowchart of a method for assembling material at the tip of a switch rail according to the present invention;

[0022] Figure 2 This is a schematic diagram of the billet structure in the material gathering method for the tip rail of the present invention;

[0023] Figure 3 This is the reference shape of the die cavity cross section in the small material gathering area of ​​the material gathering method of the tip rail of the present invention;

[0024] Figure 4 This is a correction diagram of the reference shape of the die cavity cross section in the small material gathering area of ​​the present invention, which is a material gathering method for the tip of a rail.

[0025] Figure 5 This is the reference shape of the mold cavity cross-section in the large material gathering area of ​​the present invention, which is a material gathering method for the tip of a rail.

[0026] Figure 6 This is a correction diagram of the reference shape of the mold cavity cross section in the large material gathering area of ​​the present invention, which is a material gathering method for the tip of the rail.

[0027] Among them, 1. Clamping area; 2. Material gathering area; 3. Large material gathering area; 4. Small material gathering area; 5. Switch rail heel transition area; 6. Switch rail heel forming area. Detailed Implementation

[0028] The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the protection scope of the present invention.

[0029] Specifically, such as Figures 1 to 6 The method shown includes:

[0030] S1, clamp and fix the billet in the clamping area, and place the material gathering area of ​​the billet into the mold cavity of different cross-sectional areas in sections; the whole billet is divided into a clamping area and a material gathering area. The clamping area of ​​the billet is clamped and fixed by a clamping device such as a robot arm. The material gathering area is divided into a large material gathering area and a small material gathering area according to different material gathering ratios. The large material gathering area is located at one end closer to the clamping area of ​​the billet, and the small material gathering area is located at one end farther away from the clamping area of ​​the billet. The reference size of the mold cavity of the large material gathering area is larger than that of the mold cavity of the small material gathering area. Since the amount of upsetting is determined by the size of the mold cavity, the reference size of the mold cavity of the small material gathering area is smaller, so the small material gathering area has less material, and the reference size of the mold cavity of the large material gathering area is larger, so the large material gathering area has more material.

[0031] S2: The billet is heated in segments, with the billet heating temperature in the large accumulation zone being higher than that in the small accumulation zone. This makes the plasticity of the large accumulation zone greater than that of the small accumulation zone, thus allowing more material to accumulate during processing in the large accumulation zone.

[0032] S3: The die punch performs segmented upsetting of the material accumulation zone according to the material accumulation ratio and length of different material accumulation zones. By segmented heating and using different reference dimensions for the material accumulation die cavity, more favorable deformation conditions are generated for the material accumulation of the billet near the transition zone of the switch rail heel. This ensures that the billet in the material accumulation zone obtains a good material accumulation effect, realizes small-scale material accumulation in the forming zone of the switch rail heel, and moderately adjusts the shape of the heel, making it easier for subsequent forging.

[0033] Specifically, the heating temperature of the forging billet in the large aggregate zone is determined based on the initial forging temperature of the billet material, while the heating temperature of the forging billet in the small aggregate zone is 50°C-100°C lower than that in the large aggregate zone. Billet heating is a crucial step before hot forging. After the billet is heated to a certain temperature, its plasticity increases, and its resistance to deformation decreases. Induction heating is used for both the large and small aggregate zones. Different alternating currents are applied to the inductors in the large and small aggregate zones. Under the influence of the generated alternating magnetic field, alternating potentials are generated within the large and small aggregate zones, forming alternating eddy currents. This achieves segmented heating of the large and small aggregate zones, with the plasticity of the large aggregate zone being greater than that of the small aggregate zone. The preferred heating temperature for the large aggregate zone is 1150°C, and the preferred heating temperature for the small aggregate zone is 1070°C.

[0034] Specifically, such as Figure 2 As shown, the large material gathering area is divided into a switch rail heel end transition area and a switch rail heel end forming area according to different processing areas. The switch rail heel end transition area is located at one end close to the clamping area of ​​the blank, and the switch rail heel end forming area is located at the other end away from the clamping area of ​​the blank. The length of the large material gathering area is not less than the sum of the length of the switch rail heel end transition area and half the length of the switch rail heel end forming area. In this embodiment, the total length of the material gathering area is 950mm, the length of the switch rail heel end transition area is 150mm, and the large material gathering area is the sum of the lengths of the switch rail heel end transition area and half the length of the switch rail heel end forming area, i.e., 550mm.

[0035] Specifically, the transition area and the forming area of ​​the switch rail heel are connected by a G1 curved surface, the length of which is 1 / 10 of the total length of the material gathering area. During processing, the heights of the transition area and the forming area of ​​the switch rail heel are different, and the transition area and the forming area of ​​the switch rail heel are connected by a G1 curved surface. In this embodiment, the length of the G1 curved surface is 95mm.

[0036] Specifically, the shape of the die punch is consistent with the cross-sectional shape of the blank, and the formula for calculating the working stroke S of the die punch is:

[0037] S=(C-1)LK

[0038] Where C represents the aggregate ratio, which is the ratio of the cross-sectional area of ​​the aggregated region after aggregate formation to the cross-sectional area of ​​the aggregated region before aggregate formation; L represents the length of the different aggregate ratio segments in the aggregated region; and K represents the stroke coefficient, with a value ranging from 1 to 1.15. The heated billet is placed into the die cavity, clamping the non-aggregated end. The die punch contacts the end face of the tip rail and continuously upsetting inwards. The working stroke S of the die punch is determined according to the die punch working stroke calculation formula, which is preferably 125.4 mm in this embodiment, with the stroke coefficient K preferably set to 1.1. After the punch has reached the upsetting position, it retracts, the upper and lower dies open, and the forging is removed, completing the aggregate processing of the large and small aggregated regions.

[0039] Specifically, the cross-sectional reference shape of the die cavity in the small material gathering area is obtained by uniformly offsetting the blank shape outwards, and the magnitude of the offset is determined by the material gathering ratio of the small material gathering area; the bottom shape of the die cavity in the small material gathering area is obtained by modifying the cross-sectional reference shape of the die cavity in the small material gathering area; the length of the long limb of the die cavity in the small material gathering area is the length after offsetting the reference size of the die cavity in the small material gathering area inwards by 1-2 times, and the length of the short limb of the die cavity in the small material gathering area is the length after offsetting the reference size of the die cavity in the small material gathering area outwards by 1 time.

[0040] Specifically, the reference shape of the mold cavity cross-section in the large material gathering area is obtained by uniformly offsetting the cross-sectional shape of the mold cavity in the small material gathering area outward by 1-2mm; the bottom shape of the mold cavity in the large material gathering area is obtained by modifying the reference shape of the cross-section of the mold cavity in the large material gathering area; the length of the long limb of the mold cavity in the large material gathering area is the length after offsetting the reference size of the mold cavity in the large material gathering area inward by 1-2 times; the length of the short limb of the mold cavity in the large material gathering area is the length after offsetting the reference size of the mold cavity in the large material gathering area outward by 1 time.

[0041] Specifically, in this embodiment, the offset required for designing the mold cavity cross-sectional shape is calculated to be approximately 2mm based on the ratio of the cross-sectional area after material aggregation to the cross-sectional area before material aggregation. The reference shape of the mold cavity cross-section in the small material aggregation area is as follows: Figure 2 As shown by the solid line, the shape of the billet is as follows: Figure 3 As shown by the dashed lines, the solid lines represent the portion obtained by uniformly offsetting the dashed lines outwards by 2mm. Because the two ends of the switch rail base are not aligned before forging but become symmetrical afterward, the cross-sectional shape of the die cavity in the small material accumulation area needs to be modified according to its basic shape. The modification result is as follows... Figure 5 As shown, the specific method of correction is to shorten the long limb of the die cavity in the small material gathering area by 4mm (twice the offset) compared to the reference shape, and extend the short limb of the die cavity in the small material gathering area by 2mm (one offset). Thus, the long limb of the die cavity in the small material gathering area is shortened by 2mm relative to the billet, and the short limb is extended by 4mm relative to the billet. The reference shape of the die cavity cross section in the large material gathering area is obtained by uniformly offsetting the reference shape of the die cavity cross section in the small material gathering area by 1mm. Figure 5 As shown by the solid line, the actual shape is uniformly offset outward by 3mm from the blank shape. The shape of the mold cavity cross-section in the large material accumulation area is modified according to its basic shape, and the modification result is as follows. Figure 6As shown, the specific method of correction is to shorten the long limb of the mold cavity in the large material gathering area by 3mm inward compared to the reference shape, which is twice the offset, and extend the short limb of the mold cavity in the large material gathering area by 3mm outward, which is once the offset. In this way, the long limb of the mold cavity in the large material gathering area is shortened by 3mm relative to the blank, and the short limb of the mold cavity in the large material gathering area is extended by 6mm relative to the blank, thereby determining the selected cavity size.

[0042] The present invention has been further described above with reference to specific embodiments. However, it should be understood that the specific description herein should not be construed as limiting the nature and scope of the present invention. Various modifications made to the above embodiments by those skilled in the art after reading this specification are all within the scope of protection of the present invention.

Claims

1. A method for agglomerating material at the heel end of a switch rail, characterized in that: The method includes, S1, clamp and fix the clamping area of ​​the billet, and place the aggregated parts of the billet into the mold cavity of different cross-sectional areas in sections; S2: The material accumulation zone of the billet is heated in segments; The material gathering zone is divided into a large material gathering zone and a small material gathering zone according to different material gathering ratios. The large material gathering zone is located at one end close to the clamping zone of the billet, and the small material gathering zone is located at one end far from the clamping zone of the billet. The billet heating temperature in the large material gathering zone is higher than the forging billet heating temperature in the small material gathering zone, and the material gathering ratio in the large material gathering zone is higher than that in the small material gathering zone. The large material gathering area is divided into a switch rail heel end transition area and a switch rail heel end forming area according to different processing areas. The switch rail heel end transition area is located at one end close to the clamping area of ​​the blank, and the switch rail heel end forming area is located at one end away from the clamping area of ​​the blank. The length of the large material gathering area is not less than the sum of the length of the switch rail heel end transition area and half the length of the switch rail heel end forming area. S3: The polymer zone is segmented and upsetting is performed by the die punch according to the polymer ratio and length of the different polymer zones.

2. The method for agglomerating the tip of a switch rail according to claim 1, characterized in that: The billet heating temperature in the large aggregate zone is determined based on the initial forging temperature of the billet material, and the billet heating temperature in the small aggregate zone is 50°C-100°C lower than that in the large aggregate zone.

3. The method for agglomerating the tip of a switch rail according to claim 1, characterized in that: The transition area between the tip rail heel end and the tip rail heel end forming area are connected by a G1 curved surface, the length of which is 1 / 10 of the total length of the material gathering area.

4. The method for agglomerating the tip of a switch rail according to claim 1, characterized in that: The shape of the die punch is consistent with the cross-sectional shape of the blank, and the formula for calculating the working stroke S of the die punch is: S=(C-1) L K Where C represents the aggregate ratio, which is the ratio of the cross-sectional area of ​​the aggregated zone after aggregate formation to the cross-sectional area of ​​the aggregated zone before aggregate formation; L represents the length of the aggregated zone segments with different aggregate ratios; and K represents the stroke coefficient, with a value ranging from 1 to 1.

15.

5. The method for agglomerating the tip of a rail according to claim 1, characterized in that: The cross-sectional reference shape of the mold cavity in the small aggregate zone is obtained by uniformly offsetting the blank shape outwards, and the magnitude of the offset is determined by the aggregate ratio of the small aggregate zone.

6. The method for agglomerating the tip of a switch rail according to claim 5, characterized in that: The shape of the bottom of the mold cavity of the small material gathering area is obtained by modifying the cross-sectional reference shape of the mold cavity of the small material gathering area. The length of the long limb of the mold cavity of the small material gathering area is the length after the reference size of the mold cavity of the small material gathering area is offset inward by 1-2 times. The length of the short limb of the mold cavity of the small material gathering area is the length after the reference size of the mold cavity of the small material gathering area is offset outward by 1 time.

7. The method for agglomerating the tip of a switch rail according to claim 6, characterized in that: The reference shape of the mold cavity cross-section of the large material gathering area is obtained by uniformly offsetting the cross-sectional shape of the mold cavity of the small material gathering area outward by 1-2mm.

8. The method for agglomerating the tip of a switch rail according to claim 7, characterized in that: The shape of the bottom of the mold cavity of the large material gathering area is obtained by modifying the cross-sectional reference shape of the mold cavity of the large material gathering area. The length of the long limb of the mold cavity of the large material gathering area is the length after offset inward by 1-2 times the reference size of the mold cavity of the large material gathering area. The length of the short limb of the mold cavity of the large material gathering area is the length after offset outward by 1 time the reference size of the mold cavity of the large material gathering area.

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