Welding platform and welding method for movable arm of excavator

Abstract

According to the disclosed welding platform, a plurality of supporting frames are arranged on a platform body, supporting bases are arranged at the two ends and the middle of the platform body respectively, pneumatic clamps are installed at the two ends and the middle of the platform body respectively, and pneumatic pressing tools are further installed at the two ends of the platform body respectively; the disclosed welding method for the movable arm of the excavator comprises the steps that the movable arm is assembled on a welding platform and is subjected to local spot fixed position welding; the movable arm is limited and fixed through the pneumatic clamp and the pneumatic pressing tool; symmetrical and synchronous welding is conducted on the two sides of the movable arm, welding seams between side plates and upper and lower cover plates are welded in a segmented mode, and welding is conducted gradually from the middle section of the movable arm to the two ends. According to the welding platform, the two ends and the middle section of the movable arm can be limited and fixed in the horizontal direction and the vertical direction, and the deformation resistance of the movable arm during welding is greatly improved; according to the welding method, the deformation quantity generated by the welding seams on the two sides can be counteracted through the symmetrical and synchronous welding mode on the two sides of the movable arm, and therefore the welding deformation of the movable arm is effectively controlled.

Description

Technical Field

[0001] The present invention belongs to the field of manufacturing of excavator booms, and particularly relates to a welding platform and a welding method for an excavator boom. Background Art

[0002] Existing excavator booms are usually assembled and welded from multiple plate components. Since the boom is a slender structure and the weld seams are also long, during the welding process, the weld metal expands due to high temperature and generates tensile force during cooling, which easily causes welding deformation of the excavator boom. Summary of the Invention

[0003] In order to reduce the welding deformation of the excavator boom during the manufacturing process, the present invention provides a welding platform and a welding method for an excavator boom.

[0004] A disclosed welding platform includes a platform body, a support frame, a support seat, a pneumatic fixture, and a pneumatic press; a plurality of support frames are fixedly arranged at intervals on the platform body, support seats are fixedly arranged at both ends and in the middle of the platform body respectively, a U-shaped through groove is formed in the support seat, pneumatic fixtures are installed at both ends and in the middle of the platform body respectively, and pneumatic presses are also installed at both ends of the platform body respectively;

[0005] The pneumatic fixture includes a first cylinder, a second cylinder, a guide rail, a sliding seat, and a long strip clamp; the first cylinder and the second cylinder are respectively arranged at both ends of the guide rail, and the guide rail, the first cylinder, and the second cylinder are all fixedly connected to the platform body; the ends of the telescopic rods of the first cylinder and the second cylinder are respectively fixedly connected with a sliding seat, both sliding seats are installed on the guide rail, the top surface of the sliding seat is fixedly connected with a long strip clamp, the long strip clamp is arranged vertically, and under the drive of the first cylinder and the second cylinder, the two sliding seats can drive the long strip clamp to slide inwards along the guide rail, so as to clamp the boom;

[0006] The pneumatic press includes a base, a third cylinder, and a pressing arm; the base is fixedly connected to the platform body, the cylinder body of the third cylinder is hinged to the side surface of the base through a support plate, the end of the telescopic rod of the third cylinder is hinged to the middle of the pressing arm, one end of the pressing arm is hinged to the top of the base, and under the drive of the third cylinder, the pressing arm can press down.

[0007] Further, the pneumatic fixture further includes a fourth cylinder and a pressing plate; the inner side surface of the top of the long strip clamp is fixedly installed with a fourth cylinder through a mounting seat, and the end of the telescopic rod of the fourth cylinder is fixedly connected with a pressing plate; after the two long strip clamps clamp the boom, the fourth cylinder drives the pressing plate to also press the boom tightly.

[0008] A disclosed welding method for an excavator boom uses the above-mentioned welding platform and includes the following steps:

[0009] S1. Assemble the boom on the welding platform and perform partial spot fixing welding, and pre-assemble the connecting shaft so that the assembled boom is placed on the support frame, and the pre-assembled connecting shaft is placed in the U-shaped through groove of the corresponding support seat;

[0010] S2. Start the first cylinder and the second cylinder of the pneumatic fixture, and clamp the boom through the two long strip clamping plates of the pneumatic fixture. A total of three pneumatic fixtures can clamp the two ends and the middle section of the boom in the horizontal direction;

[0011] Then start the third cylinder of the pneumatic press tool first, and press the two ends of the boom against the corresponding support frame through the pressing arm of the pneumatic press tool. Finally, start the fourth cylinder of the pneumatic fixture, and press the middle section of the boom against the corresponding support frame through the pressing plate of the pneumatic fixture to realize the pressing of the two ends and the middle section of the boom in the vertical direction;

[0012] Through such "all-round" clamping and pressing, during the subsequent welding process, the welding deformation can be effectively restricted, especially the torsional deformation and welding warping, which greatly improves the anti-deformation ability of the boom during welding.

[0013] S3. On both sides of the boom, symmetrically and synchronously weld the welds between adjacent side plates and the welds between the side plates and the upper and lower cover plates, which can form symmetric welds on both side surfaces of the boom. Symmetric synchronous welding can make the deformation amounts generated by the welds on both sides of the boom cancel each other out, thereby effectively controlling the bending deformation of the boom. The welds between the side plates and the upper and lower cover plates also need to be welded in a segmented manner to disperse the welding stress and reduce the influence caused by the too long weld. Finally, weld the welds between adjacent cover plates; all the welding is carried out step by step from the middle section of the boom to both ends, which can also make the welding deformation amounts generated at both ends of the boom cancel each other out to reduce the bending deformation;

[0014] S4. After the boom is welded, grind the welds to release the welding stress.

[0015] Further, in step S1, at least one support bar is also spot welded between the two rear connecting plates of the boom. This support bar can relatively fix the two rear connecting plates to limit the welding deformation of the boom at this place, and the support bar is removed after all the welding in step S3 is completed.

[0016] Further, in step S3, partitions are also provided between adjacent side plates of the boom. The end surfaces of the side plates are ground with slopes at the corresponding partitions, and welding is carried out in the area formed by the slopes and the end surfaces of the corresponding partitions. The welds formed in this way, in addition to making the welding firm, also weld the end surfaces of the partitions. The partitions can resist the shrinkage deformation of the welds, especially the transverse compression deformation, to reduce the deformation borne by the side plates of the boom.

[0017] Preferably, the material of the boom is HG70. CO2 gas shielded welding is used for welding, the welding wire is selected as ER50-6, the welding current is 265A, the welding voltage is 23V, and the welding speed is controlled at 2.6mm / s.

[0018] Through the above technical solutions, the present invention has at least the following beneficial effects:

[0019] In the welding platform described in the technical solution of the present application, through the design of components such as the support frame, support seat, pneumatic fixture, and pneumatic press, the two ends and the middle section of the boom can be limited and fixed in the horizontal and vertical directions. Such "all-round" clamping and pressing can effectively limit the welding deformation, especially the torsional deformation and welding warping, during the subsequent welding process, greatly improving the anti-deformation ability of the boom during welding.

[0020] In the welding method of the excavator boom, the symmetric synchronous welding method on both sides of the boom can form symmetric welds on both side surfaces of the boom, enabling the deformation amounts generated by the welds on both sides to cancel each other out, thereby effectively controlling the bending deformation of the boom; the segmented welding method for long welds and the welding method starting from the middle section of the boom and gradually proceeding towards both ends can also reduce the bending deformation of the boom to a certain extent.

[0021] In a further solution, the setting of the partition plate can resist the shrinkage deformation of the weld at this place, especially the transverse compression deformation, after welding in the area formed by the slope of the adjacent side plates of the boom and the end face of the corresponding partition plate, so as to reduce the deformation borne by the side plates of the boom. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the drawings. These drawings are all simplified schematic diagrams, only illustrating the basic structure of the present invention in a schematic manner, so they only show the components related to the present invention.

[0023] Figure 1 It is a schematic diagram of the overall structure of the welding platform described in the embodiment of the present application;

[0024] Figure 2 For Figure 1 an enlarged view of part A in

[0025] Figure 3 It is a schematic diagram of the excavator boom being welded on the welding platform;

[0026] Figure 4 It is a schematic diagram of another perspective of the excavator boom being welded on the welding platform;

[0027] Figure 5 It is a schematic diagram of the side plate of the excavator boom at the partition plate. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0028] In the description of the present application, it should be understood that if there are terms such as "upper", "lower", "left", "right", "front", "rear", etc., indicating the orientation or positional relationship, they are based on the orientation or positional relationship shown in the drawings. This is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation. Therefore, the terms describing the positional relationship are only for illustrative purposes and should not be construed as a limitation of this patent. If there are terms such as "first", "second", etc., they are only for descriptive purposes and should not be construed as indicating or implying relative importance or implicitly specifying the number of the indicated technical features. Thus, the features defined with "first", "second", etc. may explicitly or implicitly include one or more of the said features. For those of ordinary skill in the art, the specific meanings of the above terms can be understood according to specific circumstances.

[0029] In the description of the present application, it should be noted that unless otherwise clearly defined and limited, terms such as "installation", "provided with", "connection", etc. should be understood in a broad sense. For example, "connection" can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be directly connected or indirectly connected through an intermediate medium, and it can be the communication inside two elements. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0030] Reference Figures 1 to 4 A welding platform, which comprises a platform body 1, a support frame 2, a support seat 3, a pneumatic fixture 4 and a pneumatic press 5; a plurality of support frames 2 are fixedly arranged at intervals on the platform body 1, support seats 3 are fixedly arranged at both ends and in the middle of the platform body 1 respectively, a U-shaped through groove 301 is formed in the support seat 3, pneumatic fixtures 4 are installed at both ends and in the middle of the platform body 1 respectively, and pneumatic presses 5 are also installed at both ends of the platform body 1 respectively;

[0031] Reference Figure 2, the pneumatic clamp 4 includes a first cylinder 401, a second cylinder 402, a guide rail 403, a sliding seat 405 and a long strip clamping plate 406; the first cylinder 401 and the second cylinder 402 are respectively arranged at both ends of the guide rail 403, and the guide rail 403, the first cylinder 401 and the second cylinder 402 are all fixedly connected to the platform body 1; the ends of the telescopic rods of the first cylinder 401 and the second cylinder 402 are respectively fixedly connected with a sliding seat 405, and both sliding seats 405 are installed on the guide rail 403. The top surface of the sliding seat 405 is fixedly connected with a long strip clamping plate 406. The long strip clamping plate 406 is vertically arranged. Driven by the first cylinder 401 and the second cylinder 402, the two sliding seats 405 can drive the long strip clamping plate 406 to slide inwards along the guide rail 403, so as to clamp the boom.

[0032] Reference Figure 2 , the pneumatic press 5 includes a base 501, a third cylinder 503 and a pressing arm 502; the base 501 is fixedly connected to the platform body 1. The cylinder body of the third cylinder 503 is hinged to the side surface of the base 501 through a support plate 504, and the end of the telescopic rod of the third cylinder 503 is hinged to the middle of the pressing arm 502. One end of the pressing arm 502 is hinged to the top of the base 501. Driven by the third cylinder 503, the pressing arm 502 can press downwards.

[0033] Reference Figure 2 , the pneumatic clamp 4 further includes a fourth cylinder 404 and a pressing plate 407; the inner side surface of the top of the long strip clamping plate 406 is fixedly installed with a fourth cylinder 404 through a mounting seat, and the end of the telescopic rod of the fourth cylinder 404 is fixedly connected with a pressing plate 407; after the two long strip clamping plates 406 clamp the boom, the fourth cylinder 404 drives the pressing plate 407 to also press the boom downwards.

[0034] The dimensions of the boom of the excavator to be welded and manufactured are 4680mm * 1335mm * 845mm, which is welded by multiple metal plates. The maximum thickness of the metal plates is 70mm, the minimum thickness is 25mm, and the material is HG70, which has high strength and good welding performance.

[0035] The welding method of this excavator boom uses the above-mentioned welding platform, reference Figure 3 and Figure 4 , including the following steps:

[0036] S1. Assemble the boom on the welding platform and perform partial spot fixing welding, and pre-assemble the connecting shaft 8 so that the assembled boom is placed on the support frame 2, and the pre-assembled connecting shaft 8 is placed in the U-shaped through groove 301 of the corresponding support seat 3; At least one support bar 9 is also spot welded between the two rear end connection plates of the boom. The support bar 9 can relatively fix the two rear end connection plates to limit the welding deformation of the boom at this position. The support bar 9 will be removed after all welding in the subsequent S3 step is completed.

[0037] S2. Start the first cylinder 401 and the second cylinder 402 of the pneumatic fixture 4, and clamp the boom through the two long strip clamping plates 406 of the pneumatic fixture 4. A total of three pneumatic fixtures 4 can clamp the two ends and the middle section of the boom in the horizontal direction;

[0038] Then start the third cylinder 503 of the pneumatic press 5 first, and press the two ends of the boom against the corresponding support frame 2 through the pressing arm 502 of the pneumatic press 5. Finally, start the fourth cylinder 404 of the pneumatic fixture 4, and press the middle section of the boom against the corresponding support frame 2 through the pressing plate 407 of the pneumatic fixture 4 to achieve the pressing of the two ends and the middle section of the boom in the vertical direction;

[0039] Through such "all-round" clamping and pressing, during the subsequent welding process, the welding deformation can be effectively restricted, especially the torsional deformation and welding warping, greatly improving the anti-deformation ability of the boom during welding.

[0040] S3. On both sides of the boom, symmetrically and synchronously weld the welds between adjacent side plates and the welds between the side plates and the upper and lower cover plates, which can form symmetric welds on both sides of the boom. Symmetric synchronous welding can make the deformation amounts generated by the welds on both sides of the boom cancel each other out, thereby effectively controlling the bending deformation of the boom; The welds between the side plates and the upper and lower cover plates also need to be welded in a segmented manner to disperse the welding stress and reduce the influence caused by the too long weld. Finally, weld the welds between adjacent cover plates; The welding is carried out step by step from the middle section of the boom to both ends, which can also make the welding deformation amounts generated at both ends of the boom cancel each other out to reduce the bending deformation;

[0041] Reference Figure 5 , partitions 6 are also provided between adjacent side plates of the above-mentioned boom. The end faces of the side plates are ground with slopes 7 at the corresponding partitions 6, and welding is carried out in the area formed by the adjacent slopes 7 and the end faces of the corresponding partitions 6. The welds formed in this way, in addition to making the welding firm, also weld the end faces of the partitions 6. The partitions 6 can resist the shrinkage deformation of the welds, especially the transverse compressive deformation, to reduce the deformation borne by the boom side plates.

[0042] The above welding uses CO2 gas shielded welding. The welding wire selected is ER50-6, the welding current is 265A, the welding voltage is 23V, and the welding speed is controlled at 2.6mm / s.

[0043] S4. After the boom welding is completed, grind the weld seam to release the welding stress.

[0044] For the boom completed by welding through the above method, at the most serious part of its welding deformation, the torsional deformation is 2.2mm and the bending deformation is 4.3mm, which is much lower than the deformation produced by the conventional welding method and has almost no impact on the quality and performance of the excavator boom.

[0045] The above are only the preferred embodiments of the present invention and are not intended to limit the present invention. Based on the inspiration of the present invention, through the above description, relevant personnel can completely make various changes and modifications without departing from the technical idea of the present invention. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principle of the present invention shall be included within the protection scope of the present invention.

Claims

1. A welding platform, characterized in that: The invention comprises a platform body (1), a support frame (2), a support seat (3), a pneumatic clamp (4) and a pneumatic pressing tool (5); a plurality of support frames (2) are fixedly arranged at intervals on the platform body (1); support seats (3) are fixedly arranged at both ends and the middle of the platform body (1); a U-shaped through groove (301) is provided on the support seat (3); pneumatic clamps (4) are installed at both ends and the middle of the platform body (1); and pneumatic pressing tools (5) are also installed at both ends of the platform body (1); The pneumatic clamp (4) comprises a first cylinder (401), a second cylinder (402), a guide rail (403), a slide seat (405) and a long clamp plate (406); the first cylinder (401) and the second cylinder (402) are respectively arranged at two ends of the guide rail (403), and the guide rail (403), the first cylinder (401) and the second cylinder (402) are all fixedly connected to the platform body (1); the ends of the telescopic rods of the first cylinder (401) and the second cylinder (402) are respectively fixedly connected to the slide seat (405), and the two slide seats (405) are both installed on the guide rail (403), and the top surface of the slide seat (405) is fixedly connected to the long clamp plate (406), and the long clamp plate (406) is vertically arranged; The pneumatic press (5) comprises a base (501), a third cylinder (503) and a press arm (502); the base (501) is fixedly connected to the platform body (1), the cylinder body of the third cylinder (503) is hinged to the side of the base (501), the end of the telescopic rod of the third cylinder (503) is hinged to the middle of the press arm (502), and one end of the press arm (502) is hinged to the top of the base (501).

2. A welding platform according to claim 1, characterized in that: The pneumatic clamp (4) further comprises a fourth cylinder (404) and a pressure plate (407); the fourth cylinder (404) is fixedly mounted on the top inner side surface of the long clamp (406) via a mounting seat, and the end of the telescopic rod of the fourth cylinder (404) is fixedly connected to the pressure plate (407).

3. A welding method for an excavator boom, characterized in that: Using the welding platform described in claim 2, comprising the following steps: S1. Assemble the boom on the welding platform and perform local spot welding, and pre-install the connecting shaft (8), so that the assembled boom is placed on the support frame (2), and the pre-installed connecting shaft (8) is placed in the U-shaped through groove (301) of the corresponding support seat (3); S2. Start the first cylinder (401) and the second cylinder (402) of the pneumatic clamp (4), and clamp the boom through the two long clamps (406) of the pneumatic clamp (4). A total of three pneumatic clamps (4) can clamp the ends and the middle section of the boom in the horizontal direction; Then, the third cylinder (503) of the pneumatic press (5) is started, and the two ends of the movable arm are pressed against the corresponding support frame (2) through the pressing arm (502) of the pneumatic press (5), and finally, the fourth cylinder (404) of the pneumatic clamp (4) is started, and the middle section of the movable arm is also pressed against the corresponding support frame (2) through the pressing plate (407) of the pneumatic clamp (4), so as to realize the pressing of the two ends and the middle section of the movable arm in the vertical direction; S3. On both sides of the boom, the welds between adjacent side plates and the welds between the side plates and the upper and lower cover plates are welded symmetrically and synchronously. The welds between the side plates and the upper and lower cover plates are welded in sections, and finally the welds between adjacent cover plates are welded; the welding is carried out gradually from the middle section of the boom to both ends; S4. After the boom welding is completed, grind the weld to release the welding stress.

4. The welding method of an excavator boom according to claim 3, characterized in that: In step S1, at least one support bar (9) is spot-welded between the two rear end connecting plates of the boom, and the support bar (9) is removed after all welding in step S3 is completed.

5. The welding method of an excavator boom according to claim 3, characterized in that: In step S3, a partition plate (6) is further arranged between adjacent side plates of the boom, a slope (7) is ground on the end surface of the side plate at the position corresponding to the partition plate (6), and welding is performed in the area formed by the adjacent slope (7) and the end surface of the corresponding partition plate (6).

6. A welding method for an excavator boom according to any one of claims 3 to 5, characterized in that: The material of the movable arm is HG70, the welding adopts CO2 gas shielded welding, the welding wire is ER50-6, the welding current is 265A, the welding voltage is 23V, and the welding speed is controlled at 2.6mm / s.

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