Anti-fatigue box type welding structure, welding method and pump truck conveying pipe support

Abstract

The application discloses an anti-fatigue box type welding structure, a welding method and a pump truck conveying pipe support, which comprises a bottom plate, an upper cover plate, left and right side plates arranged between the bottom plate and the upper cover plate, first through holes for mounting conveying pipes arranged on the left and right side plates respectively, a box type structure formed by the bottom plate, the left and right side plates and the upper cover plate, and a conveying pipe support arranged in the box type structure. The conveying pipe is protected in the support by arranging the conveying pipe support in the box type structure, so that the rigidity and stability of the whole box type structure are improved, the damage effect of alternating loads on the welding seam during the service of the welding structure is reduced, the stress environment of the box type structure is effectively improved, and the anti-fatigue cracking performance of the fillet weld of the box type structure is improved.

Description

Technical Field

[0001] This invention belongs to the field of concrete pump truck technology, specifically relating to a fatigue-resistant box-type welded structure, welding method, and pump truck delivery pipe support. Background Technology

[0002] Welded structures are inevitably used in fields such as engineering machinery, aerospace, shipbuilding, and rail transportation. The quality of these welded structures directly affects the quality of the finished product. Studies have shown that 90% of safety accidents caused by welded structure fractures are due to fatigue failure. Therefore, ensuring the fatigue performance of welded structures has become a key consideration for product designers.

[0003] The main factor affecting the fatigue performance of welded structural components is stress concentration, which often occurs at geometric discontinuities in the structure. This determines that fillet welds have a high level of stress concentration. Especially at the weld toe of the fillet weld, fatigue cracks are prone to occur and propagate, leading to overall structural failure. Due to the harsh operating conditions and complex stress states of engineering machinery during service, it suffers from serious fatigue risks. Taking the boom structure of a concrete pump truck as an example, it mainly adopts a box-type structure, connecting the upper cover plate, left and right side plates, and lower base plate through numerous welds, mostly T-joints forming fillet welds. In actual operation, fatigue cracking frequently occurs at the circular fillet welds connecting the delivery pipe and the boom of the pump truck. Therefore, achieving a reliable connection between the box structure and the delivery pipe, and ensuring its fatigue resistance, is an important task for relevant personnel. Summary of the Invention

[0004] To address the shortcomings of existing technologies, this invention provides a fatigue-resistant box-type welded structure, a welding method, and a pump truck delivery pipe support, which can effectively improve the stress environment of the box-type structure and enhance the fatigue crack resistance of the fillet welds in the box-type structure.

[0005] To achieve the above objectives, the technical solution adopted by the present invention is as follows:

[0006] In a first aspect, a fatigue-resistant box-type welded structure is provided, comprising: a base plate; a top cover plate; a left side plate and a right side plate disposed between the base plate and the top cover plate; a first through hole for installing a conveying pipe is respectively provided on the left side plate and the right side plate; the base plate, the left side plate, the right side plate and the top cover plate form a box-type structure; and a conveying pipe support is provided inside the box-type structure.

[0007] Furthermore, the base plate and the top cover plate are parallel to each other.

[0008] Furthermore, the left side plate and the right side plate are parallel to each other and perpendicular to the bottom plate and the top cover plate.

[0009] Furthermore, the conveying pipe support includes a first stiffener and a second stiffener. The first stiffener is perpendicular to the bottom plate, the left side plate, the right side plate, and the top cover plate, respectively. The second stiffener is parallel to the first stiffener and is located on both sides of the conveying pipe.

[0010] Furthermore, the conveying pipe support includes a third rib, a fourth rib, a fifth rib, and a sixth rib. The third rib is perpendicular to the bottom plate, the left side plate, the right side plate, and the top cover plate, respectively. The fourth rib is parallel to the third rib and is located on both sides of the conveying pipe. The fifth and sixth ribs are located between the third and fourth ribs. The fifth rib is perpendicular to both the third and fourth ribs, and the sixth rib is parallel to the fifth rib. The fifth and sixth ribs are provided with second through holes for installing the conveying pipe.

[0011] Furthermore, the conveying pipe support includes a seventh rib, an eighth rib, and a ninth rib, which form an "X" shape. The seventh rib, the eighth rib, and the ninth rib are perpendicular to the base plate and form a set angle with the left side plate. The conveying pipe passes through the connection of the seventh rib, the eighth rib, and the ninth rib.

[0012] Secondly, a welding method for a fatigue-resistant box-type welded structure is provided, comprising: splicing the bottom plate, left side plate, right side plate and top cover plate into a box-type structure; placing the first stiffening plate and the second stiffening plate on both sides of the first through hole respectively, and welding them perpendicularly to the bottom plate, left side plate, right side plate and top cover plate respectively; passing the conveying pipe through the first through hole and welding it to the left side plate and right side plate.

[0013] Thirdly, a welding method for a fatigue-resistant box-type welded structure is provided, comprising: splicing the bottom plate, left side plate, right side plate, and top cover plate into a box-type structure; welding the third stiffener perpendicularly to the bottom plate, left side plate, right side plate, and top cover plate respectively; welding the fifth stiffener and the sixth stiffener perpendicularly to the third stiffener respectively, while keeping the axis of the second through hole coincident with the axis of the first through hole; welding the fourth stiffener perpendicularly to the bottom plate, left side plate, right side plate, and top cover plate respectively; and passing the conveying pipe through the first through hole and the second through hole, and welding it to the left side plate and the right side plate.

[0014] Fourthly, a welding method for a fatigue-resistant box-type welded structure is provided, comprising: splicing the bottom plate, left side plate, right side plate, and top cover plate into a box-type structure; welding a seventh stiffener plate to the bottom plate, left side plate, right side plate, and top cover plate respectively, while keeping the seventh stiffener plate perpendicular to the bottom plate and top cover plate, and simultaneously keeping the seventh stiffener plate at a set angle to the left side plate and right side plate; welding an eighth stiffener plate to the bottom plate, left side plate, seventh stiffener plate, and top cover plate respectively, while keeping the eighth stiffener plate perpendicular to the bottom plate and top cover plate, and simultaneously... Maintain the eighth rib at a set angle to the left side plate; weld the ninth rib to the bottom plate, the seventh rib, the right side plate, and the top cover plate respectively, keeping the ninth rib perpendicular to the bottom plate and the top cover plate, while maintaining the ninth rib at a set angle to the right side plate; and form an "X" shape with the seventh, eighth, and ninth ribs; pass the conveying pipe through the first through hole and weld it to the left side plate and the right side plate, while the conveying pipe passes through the connection of the seventh, eighth, and ninth ribs.

[0015] Fifthly, a pump truck delivery pipe support is provided, characterized in that the pump truck delivery pipe support includes the fatigue-resistant box-type welded structure described in the first aspect.

[0016] Compared with the prior art, the beneficial effects achieved by the present invention are as follows:

[0017] (1) By setting a conveying pipe support inside the box-shaped structure, the present invention protects the conveying pipe inside the support, thereby improving the overall stiffness and stability of the box-shaped structure, reducing the destructive effect of alternating loads on the weld during the service of the welded structure, effectively improving the stress environment of the box-shaped structure, and improving the fatigue crack resistance of the fillet weld of the box-shaped structure. According to fatigue simulation analysis, compared with the existing structure, the fatigue life of the welded structure of the present invention is increased by 40.9%, which has a significant improvement effect.

[0018] (2) The idea of ​​this invention is to improve the structural design, improve the structural form from the upstream design to improve its fatigue performance, avoid unnecessary losses caused by unreasonable structural design, reduce subsequent test verification, and save a lot of manpower, material resources and time costs. Attached Figure Description

[0019] Figure 1 This is a schematic diagram of the overall structure of a fatigue-resistant box-type welded structure provided in Embodiment 1 of the present invention;

[0020] Figure 2 This is a schematic diagram of the overall structure of a fatigue-resistant box-type welded structure provided in Embodiment 2 of the present invention (the box structure is not shown).

[0021] Figure 3This is a schematic diagram of the overall structure of a fatigue-resistant box-type welded structure provided in Embodiment 3 of the present invention (the box structure is not shown).

[0022] In the diagram: 41. Base plate; 42. Left side plate; 43. Right side plate; 44. Top cover plate; 45. Conveying pipe; 46. First stiffener; 47. Second stiffener; 51. Third stiffener; 52. Fourth stiffener; 53. Fifth stiffener; 54. Sixth stiffener; 61. Seventh stiffener; 62. Eighth stiffener; 63. Ninth stiffener. Detailed Implementation

[0023] The present invention will be further described below with reference to the accompanying drawings. The following embodiments are only used to more clearly illustrate the technical solution of the present invention, and should not be used to limit the scope of protection of the present invention.

[0024] Example 1:

[0025] like Figure 1 As shown, a fatigue-resistant box-type welded structure includes: a base plate 41, a top cover plate 44, a left side plate 42 and a right side plate 43 disposed between the base plate 41 and the top cover plate 44; a first through hole for installing a conveying pipe 45 is provided on the left side plate 42 and the right side plate 43 respectively; the base plate 41, the left side plate 42, the right side plate 43 and the top cover plate 44 form a box-type structure; a conveying pipe support is provided inside the box-type structure.

[0026] In this embodiment, the base plate 41 and the top cover plate 44 are parallel to each other. The left side plate 42 and the right side plate 43 are parallel to each other and perpendicular to the base plate 41 and the top cover plate 44.

[0027] The conveying pipe support includes a first stiffener 46 and a second stiffener 47. The first stiffener 46 is perpendicular to the bottom plate 41, the left side plate 42, the right side plate 43 and the top cover plate 44, respectively. The second stiffener 47 is parallel to the first stiffener 46 and is located on both sides of the conveying pipe 45.

[0028] The welding method for the fatigue-resistant box-type welded structure described in this embodiment includes:

[0029] a. Test plate preparation: The required sheet metal is processed according to the actual dimensions of the structural components. The surfaces of the sheet metal to be welded are treated to remove surface oil and contaminants. The relative positions of the base plate, left side plate, right side plate, and top cover plate are fixed on the tooling platform using spot welding.

[0030] b. Box-shaped structure welding: Place the tack-fixed combined structure on the welding workbench and weld the four welds A, B, C, and D simultaneously. The weld leg size is 6mm, no beveling is required, and the welding is done on one side to form a box-shaped structure.

[0031] c. Welding of the conveying pipe support: After the box-shaped structure is welded, the first stiffening plate 46 is placed inside the box-shaped structure at a distance of 100mm from the axis of the first through hole on the side plate, so that the first stiffening plate 46 is perpendicular to the bottom plate 41 and the side plates (left side plate 42 and right side plate 43) of the box-shaped structure; single-sided welding is performed on the side of the first stiffening plate 46 away from the opening of the side plate to form four welds on the top, bottom, left and right sides, with a weld leg size of 5mm; the second stiffening plate 47 is welded in the same way. The first stiffening plate 46 and the second stiffening plate 47 constitute the support structure for the conveying pipe 45. The conveying pipe 45 is not connected to the first stiffening plate 46 or the second stiffening plate 47.

[0032] d. Welding of the conveying pipe: The conveying pipe 45 is sequentially passed through the first through hole on the right side plate 43 of the box-shaped structure, the conveying pipe support inside the box-shaped structure, and the first through hole on the left side plate 42, so that the conveying pipe 45 extends 10mm beyond the left side plate. On the outside of the box-shaped structure, the conveying pipe 45 is welded to the circumference connecting the left and right side plates of the box-shaped structure, with a weld leg size of 10mm, so that the conveying pipe 45 is connected to the box-shaped structure as a whole.

[0033] Example 2:

[0034] The only difference between this embodiment and Embodiment 1 is the structure and welding method of the delivery pipe support.

[0035] like Figure 2 As shown, the conveying pipe support includes a third stiffener 51, a fourth stiffener 52, a fifth stiffener 53, and a sixth stiffener 54. The third stiffener 51 is perpendicular to the bottom plate 41, the left side plate 42, the right side plate 43, and the top cover plate 44, respectively. The fourth stiffener 52 is parallel to the third stiffener 51 and is located on both sides of the conveying pipe 45. The fifth stiffener 53 and the sixth stiffener 54 are located between the third stiffener 51 and the fourth stiffener 52. The fifth stiffener 53 is perpendicular to both the third stiffener 51 and the fourth stiffener 52, and the sixth stiffener 54 is parallel to the fifth stiffener 53. The fifth stiffener 53 and the sixth stiffener 54 are provided with second through holes for installing the conveying pipe 45.

[0036] The welding method for the fatigue-resistant box-type welded structure described in this embodiment includes:

[0037] Steps a and b are the same as in Example 1, and are omitted here;

[0038] c. Welding of the conveying pipe support: After the box-shaped structure is welded, firstly, weld the third stiffener 51, referring to the welding method of the first stiffener 46 in Embodiment 1. Secondly, weld the fifth stiffener 53 and the sixth stiffener 54, performing single-sided fillet welds at the connection points (E and F) with the third stiffener 51, with a weld leg size of 5mm. Next, weld the fourth stiffener 52, using the same welding method and weld leg size as the third stiffener 51. When welding the fourth stiffener 52, it can be cut into three parts and welded separately according to the actual positions of the fifth stiffener 53 and the sixth stiffener 54.

[0039] d. Welding of the conveying pipe: The conveying pipe 45 is sequentially passed through the first through hole on the right side plate 43 of the box-shaped structure, the second through hole on the conveying pipe support inside the box-shaped structure, and the first through hole on the left side plate 42, so that the conveying pipe 45 extends 10mm beyond the left side plate. On the outside of the box-shaped structure, the conveying pipe 45 is welded to the circumference connecting the left and right side plates of the box-shaped structure, with a weld leg size of 10mm, so that the conveying pipe 45 is connected to the box-shaped structure as a whole.

[0040] Example 3:

[0041] The only difference between this embodiment and Embodiments 1 and 2 is the structure and welding method of the delivery pipe support.

[0042] like Figure 3 As shown, the conveying pipe support includes a seventh stiffener 61, an eighth stiffener 62, and a ninth stiffener 63. The seventh stiffener 61, the eighth stiffener 62, and the ninth stiffener 63 form an "X" shape. The seventh stiffener 61, the eighth stiffener 62, and the ninth stiffener 63 are perpendicular to the base plate 41 and form a set angle with the left side plate 42. The conveying pipe 45 passes through the connection of the seventh stiffener 61, the eighth stiffener 62, and the ninth stiffener 63.

[0043] The welding method for the fatigue-resistant box-type welded structure described in this embodiment includes:

[0044] Steps a and b are the same as in Examples 1 and 2, and are omitted here;

[0045] c. Welding of the conveying pipe support: After the box-type structure is welded, firstly, the seventh stiffener 61 is welded. The seventh stiffener 61 is perpendicular to the bottom plate 41 of the box-type structure and forms a 45° angle with the left side plate 42 and the right side plate 43. Welding is performed at points G and H to fill the gap between the seventh stiffener 61 and the left side plate 42 and the right side plate 43. Secondly, the eighth stiffener 62 is welded. The eighth stiffener 62 is perpendicular to the bottom plate 41 and forms a 45° angle with the left side plate 42. At the connection point I between the eighth stiffener 62 and the left side plate 42, a filling weld is performed. Then, at the connection point J between the eighth stiffener 62 and the seventh stiffener 61, a single-sided fillet weld is performed with a weld leg size of 5mm. Similarly, welding is performed at points K and L of the ninth stiffener 63 to form the conveying pipe support structure.

[0046] d. Welding of the conveying pipe: The conveying pipe 45 is sequentially passed through the first through hole on the right side plate 43 of the box-shaped structure, the conveying pipe support inside the box-shaped structure (passing through the connection of the seventh stiffener 61, the eighth stiffener 62, and the ninth stiffener 63), and the first through hole on the left side plate 42, so that the conveying pipe 45 extends 10mm beyond the left side plate. On the outside of the box-shaped structure, the conveying pipe 45 is welded to the circumference of the connection between the left and right side plates of the box-shaped structure, with a weld leg size of 10mm, so that the conveying pipe 45 is connected to the box-shaped structure as a whole.

[0047] To verify the fatigue performance improvement effect of the three improved structures in this application, fatigue simulation analysis was performed on the existing structures and the three solutions provided by this invention, and the fatigue life of these three solutions was compared. The welded structure of this invention has a fatigue life that is at least 40.9% higher, demonstrating a significant improvement effect.

[0048] Example 4:

[0049] Based on Embodiments 1 to 3, this embodiment provides a pump truck delivery pipe support, which includes the fatigue-resistant box-type welded structure described in any one of Embodiments 1 to 3.

[0050] The above description is only a preferred embodiment of the present invention. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the technical principles of the present invention, and these improvements and modifications should also be considered within the scope of protection of the present invention.

Claims

1. A pump truck delivery pipe support, comprising a fatigue-resistant box-type welded structure, characterized in that, The fatigue-resistant box-type welded structure includes: Base plate (41); Top cover plate (44); The left side plate (42) and the right side plate (43) are disposed between the bottom plate (41) and the top cover plate (44). First through holes for installing conveying pipes (45) are respectively provided on the left side plate (42) and the right side plate (43); the bottom plate (41), the left side plate (42), the right side plate (43) and the top cover plate (44) form a box-shaped structure; a conveying pipe support is provided inside the box-shaped structure; The conveying pipe support includes a seventh rib (61), an eighth rib (62), and a ninth rib (63). The seventh rib (61), the eighth rib (62), and the ninth rib (63) form an "X" shape. The seventh rib (61), the eighth rib (62), and the ninth rib (63) are perpendicular to the base plate (41) and form a set angle with the left side plate (42). The conveying pipe (45) passes through the connection of the seventh rib (61), the eighth rib (62), and the ninth rib (63).

2. The pump truck delivery pipe support according to claim 1, characterized in that, The bottom plate (41) and the top cover plate (44) are parallel to each other.

3. The pump truck delivery pipe support according to claim 2, characterized in that, The left side plate (42) and the right side plate (43) are parallel to each other and perpendicular to the bottom plate (41) and the top cover plate (44), respectively.

4. A welding method for a fatigue-resistant box-type welded structure, used for welding the fatigue-resistant box-type welded structure in the pump truck delivery pipe support as described in claim 1, characterized in that, include: The bottom plate (41), left side plate (42), right side plate (43) and top cover plate (44) are spliced ​​together to form a box-shaped structure; The seventh rib plate (61) is welded to the bottom plate (41), the left side plate (42), the right side plate (43) and the top cover plate (44) respectively, and the seventh rib plate (61) is kept perpendicular to the bottom plate (41) and the top cover plate (44), while the seventh rib plate (61) is kept at a set angle to the left side plate (42) and the right side plate (43); The eighth rib plate (62) is welded to the bottom plate (41), the left side plate (42), the seventh rib plate (61) and the top cover plate (44) respectively, and the eighth rib plate (62) is kept perpendicular to the bottom plate (41) and the top cover plate (44), while the eighth rib plate (62) is kept at a set angle to the left side plate (42); The ninth rib (63) is welded to the bottom plate (41), the seventh rib (61), the right side plate (43), and the top cover plate (44) respectively, and the ninth rib (63) is kept perpendicular to the bottom plate (41) and the top cover plate (44), while the ninth rib (63) is kept at a set angle to the right side plate (43); and the seventh rib (61), the eighth rib (62), and the ninth rib (63) are arranged into an "X" shaped structure. The conveying pipe (45) is passed through the first through hole and welded to the left side plate (42) and the right side plate (43). At the same time, the conveying pipe (45) passes through the connection of the seventh rib plate (61), the eighth rib plate (62) and the ninth rib plate (63).

Images