A method for constructing a sheer strake

Abstract

The present invention relates to the field of shipbuilding technology, and in particular to a method for building a sheer strake. The method for building a sheer strake comprises the steps of S1: in the stage of ship segment construction, the round steel is divided into a middle welding zone and a buffer zone at both ends along its axial direction, the welding zone of the round steel is symmetrically welded just above the sheer strake, and a non-penetration zone is formed between the round steel and the upper end surface of the sheer strake; S2: when the ship side segments are assembled or closed, each sheer strake butt joint is welded; S3: round steel is installed above each sheer strake butt joint, the two ends of the round steel across the sheer strake butt joint are respectively formed with the ends of the buffer zone of the round steel on the corresponding side, and each round steel butt joint is welded; S4: the buffer zone of the round steel and the round steel across the sheer strake butt joint are symmetrically welded just above the sheer strake. The sheer strake is welded with round steel and a non-penetration zone is formed between the two, which improves the crack resistance and crack arrest performance of the sheer strake.

Description

Technical Field

[0001] The invention relates to the technical field of ship construction, and in particular to a method for constructing a sheer strake. Background Art

[0002] When medium and large ships are sailing in severe sea conditions, for example, in a huge wave environment, the middle of the ship is at the crest of the wave, while the bow and stern are at the trough of the wave, so that the middle of the hull is subject to the upward buoyancy of the seawater, while the bow and stern are temporarily suspended (no upward buoyancy). At this time, the bow and stern of the ship tend to sink, and the middle of the ship is subject to the combined effect of the upward buoyancy and the downward gravity of the bow and stern of the ship, which tends to bend longitudinally and produce large tensile stress. In severe cases, cracks will appear from top to bottom in the side outer plate of the middle of the ship, and eventually lead to a serious marine accident in which the ship breaks from the middle. Therefore, the crack resistance and crack arrest performance of the side outer plate, especially the sheer top plate (the topmost plate in the side outer plate) is directly related to the safety of ship use.

[0003] At present, in the process of ship construction, the crack resistance requirements are mainly met by increasing the material thickness, strength and toughness level of the sheer strake. Figure 1 As shown, the sheer strake 1 is located above the main deck 10. The upper end of the sheer strake 1 is a single steel plate free edge structure. When the steel plate free edge structure is subjected to complex and large tensile stress, cracks are easily generated from its top, and the crack resistance performance is poor. Moreover, the sheer strake 1 has poor performance in preventing cracks from extending downward, that is, poor crack arrest performance. Once cracks are generated at the upper end of the sheer strake 1, the cracks are likely to extend downward, causing serious accidents.

[0004] Therefore, a method for constructing a side top strake is urgently needed to solve the above problems. Summary of the invention

[0005] The object of the present invention is to provide a method for constructing a sheer strake to improve the crack resistance and crack arrest performance of the sheer strake.

[0006] To achieve this purpose, the technical solution adopted by the present invention is:

[0007] A method for constructing a sheer strake comprises the following steps:

[0008] S1: During the ship block construction stage, the round steel is divided into a middle welding zone and slow-welding zones at both ends along its axial direction. The welding zones of the round steel are symmetrically welded just above the sheer strake, and a non-penetration zone is formed between the round steel and the upper end surface of the sheer strake;

[0009] S2: When the ship's side sections are assembled or closed, weld each side strake butt joint;

[0010] S3: The round steel is installed above each of the butt joints of the sheer strakes, and the two ends of the round steel across the butt joints of the sheer strakes are respectively connected with the ends of the slow welding zone of the round steel on the corresponding side to form a round steel butt joint, and each of the round steel butt joints is welded;

[0011] S4: The slow-welding zone of the round steel and the round steel across the butt joint of the sheer strake are symmetrically welded just above the sheer strake.

[0012] As a preferred solution, in step S2, after the welding of the sheer strake butt joint is completed, the upper end of the sheer strake butt joint is polished and smoothed to be flush with the upper end surface of the sheer strake.

[0013] As a preferred solution, step S3 includes step S31: measuring the distance H between two of the round steels on two adjacent sheer strakes, and cutting the allowance of the round steel across the joint of the sheer strakes according to the distance H.

[0014] As a preferred solution, step S3 also includes step S32: performing welding groove processing and grinding on the butt joint area of ​​the round steel.

[0015] As a preferred solution, step S3 also includes step S33: placing an isolation copper plate between the upper end surface of the side top column plate and just below each of the round steel butt joints.

[0016] As a preferred solution, step S3 also includes step S34: welding all the round steel butt joints in sequence.

[0017] As a preferred solution, when welding each of the round steel butt joints, after the welding of one side of the round steel butt joint is completed, the other side of the round steel butt joint is root cleaned and polished before welding.

[0018] As a preferred solution, the method for constructing the side top strake further includes step S5: grinding the weld surface of the round steel butt joint to be flush with the outer surface of the round steel.

[0019] As a preferred solution, the method for constructing the side top strake further includes step S6: after standing for a preset time, performing non-destructive testing on the welds of the round steel butt joints.

[0020] As a preferred solution, the slow-welding zone of the round steel and the round steel across the butt joint of the sheer strake are symmetrically welded just above the sheer strake by continuous welding.

[0021] The beneficial effects of the present invention are:

[0022] The present invention proposes a method for constructing the sheer strakes, wherein round steel is symmetrically welded just above the sheer strakes, so that the round steel can resist the tensile stress to which the ship is subjected, thereby reducing the risk of cracks in the sheer strakes and improving the crack resistance of the sheer strakes. Since a non-penetration area is formed between the round steel and the upper end surface of the sheer strakes, a non-continuous structure is formed between the upper end of the sheer strakes and the round steel. Even if the round steel is subjected to tensile stress and cracks are generated, the non-penetration area can buffer the tensile stress and prevent the cracks from extending to the sheer strakes, thereby improving the crack arresting performance of the sheer strakes. In addition, the round steel across the butt joint of the sheer strakes can stagger the butt joint of the round steel and the butt joint of the sheer strakes by a certain distance, thereby avoiding the butt joint of the sheer strakes and the butt joint of the round steel from being coplanar, thereby further improving the crack resistance of the sheer strakes. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 It is a partial structural diagram of the existing main deck and the side strake;

[0024] Figure 2 It is a main flow chart of the method for constructing the sheer strake provided by an embodiment of the present invention;

[0025] Figure 3 It is a schematic diagram of the installation structure of round steel for butt joints across the sheer top strake provided by an embodiment of the present invention;

[0026] Figure 4 is a schematic cross-sectional view of a welding structure of round steel and sheer strake provided in an embodiment of the present invention;

[0027] Figure 5 It is a detailed flow chart of the method for constructing the side top strake provided in an embodiment of the present invention.

[0028] The names and numbers of the components in the figure are as follows:

[0029] 10. Main deck; 1. Side strakes; 11. Side strakes butt joints; 2. Round steel; 21. Welding grooves; 22. Round steel butt joints; 3. Isolation copper plates. DETAILED DESCRIPTION

[0030] In order to make the technical problems solved by the present invention, the technical solutions adopted and the technical effects achieved clearer, the technical solutions of the present invention are further described below in conjunction with the accompanying drawings and through specific implementation methods. It is understood that the specific embodiments described herein are only used to explain the present invention, rather than to limit the present invention. It should also be noted that, for the convenience of description, only the parts related to the present invention are shown in the accompanying drawings, not all.

[0031] In the description of the present invention, unless otherwise clearly specified and limited, the terms "connected", "connected", and "fixed" should be understood in a broad sense, for example, it 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 a direct connection or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0032] In the present invention, unless otherwise clearly specified and limited, a first feature being "above" or "below" a second feature may include that the first and second features are in direct contact, or may include that the first and second features are not in direct contact but are in contact through another feature between them. Moreover, a first feature being "above", "above" and "above" a second feature includes that the first feature is directly above and obliquely above the second feature, or simply indicates that the first feature is higher in level than the second feature. A first feature being "below", "below" and "below" a second feature includes that the first feature is directly below and obliquely below the second feature, or simply indicates that the first feature is lower in level than the second feature.

[0033] In the description of this embodiment, the terms "upper", "lower", "right", etc., directions or positional relationships are based on the directions or positional relationships shown in the drawings, and are only for the convenience of description and simplification of operation, rather than indicating or implying that the device or element referred to must have a specific direction, be constructed and operated in a specific direction, and therefore cannot be understood as limiting the present invention. In addition, the terms "first" and "second" are only used to distinguish in the description and have no special meaning.

[0034] The technical solution of the present invention is further described below with reference to the accompanying drawings and through specific implementation methods.

[0035] At present, in the process of ship construction, the main way to meet the crack resistance requirements is to increase the material thickness, strength and toughness level of the sheer strake. Since the upper end of the sheer strake is a single steel plate free edge structure, when the steel plate free edge structure is subjected to complex and large tensile stress, cracks are easily generated from its top, and the crack resistance performance is poor. In addition, the performance of the sheer strake in preventing cracks from extending downward is poor, that is, the crack arresting performance is poor. Once cracks occur at the upper end of the sheer strake, the cracks are likely to extend downward, leading to serious accidents.

[0036] To solve the above problems, Figure 2 As shown, this embodiment also proposes a method for constructing a side top strake, which specifically includes the following steps:

[0037] S1: During the ship block construction stage, the round steel 2 is divided into a middle welding zone and slow-welding zones at both ends along its axial direction. The welding zones of the round steel 2 are symmetrically welded just above the sheer strake 1, and a non-penetration zone is formed between the round steel 2 and the upper end surface of the sheer strake 1;

[0038] S2: When the ship's side sections are assembled or closed, weld each side strake butt seam 11;

[0039] S3: round steel 2 is installed above each sheer strake butt joint 11, and both ends of the round steel 2 across the sheer strake butt joint 11 are respectively connected with the ends of the slow welding zone of the round steel 2 on the corresponding side to form a round steel butt joint 22, and each round steel butt joint 22 is welded;

[0040] S4: The slow-welding zone of the round steel 2 and the round steel 2 across the sheer strake butt joint 11 are both symmetrically welded just above the sheer strake 1.

[0041] like Figure 3 As shown, round steel 2 is symmetrically welded just above the sheer strake 1, so that the round steel 2 can resist the tensile stress of the ship, thereby reducing the risk of cracks in the sheer strake 1 and improving the crack resistance of the sheer strake 1. In addition, the round steel 2 across the sheer strake joint 11 can make the round steel joint 22 and the sheer strake joint 11 staggered by a certain distance, avoiding the sheer strake joint 11 and the round steel joint 22 from being coplanar, further improving the crack resistance of the sheer strake 1. Figure 4 As shown, after the welding of the sheer strake 1 and the round steel 2 is completed, the penetration zones of the inner and outer corner welds between the round steel 2 and the sheer strake 1 do not enter the range directly above the sheer strake 1, so that a non-penetration zone is formed between the round steel 2 and the upper end surface of the sheer strake 1, that is, a non-continuous structure exists between the upper end of the sheer strake 1 and the round steel 2. Even if the round steel 2 is subjected to tensile stress and cracks are generated, its non-penetration zone can buffer the tensile stress and prevent the cracks from extending to the sheer strake 1, thereby improving the crack arrest performance of the sheer strake 1.

[0042] For ease of understanding, now combined Figure 3 to Figure 5 The construction method of the sheer strake is described in detail. In step S1, a section of round steel 2 is symmetrically welded directly above each sheer strake 1, and the axis of the round steel 2 is located on the center plane of the sheer strake 1 along its thickness direction, and the gap between the upper end surface of the sheer strake 1 and the round steel 2 is 0 mm to 2 mm, so as to avoid the gap between the upper end surface of the sheer strake 1 and the round steel 2 being too large, thereby preventing the penetration zone of the inner and outer corner welds between the round steel 2 and the sheer strake 1 from entering directly above the sheer strake 1.

[0043] It should be noted that in order to facilitate the welding of the round steel 2 on the side top plate 1 and the round steel 2 at the seam 11 across the side top plate, only the welding area in the middle part of the round steel 2 on the side top plate 1 is welded, and a slow welding area of ​​about 300mm to 500mm is reserved at both ends of the round steel 2.

[0044] In step S2, after the welding of the sheer strake butt seam 11 is completed, the upper end of the sheer strake butt seam 11 is polished and smoothed to be flush with the upper end surface of the sheer strake 1, thereby avoiding interference between the weld on the sheer strake butt seam 11 and the round steel 2 across the sheer strake butt seam 11.

[0045] like Figure 3 and Figure 5 As shown, step S3 includes step S31: measuring the spacing H between two round steels 2 on two adjacent sheer strakes 1, and cutting the round steel 2 across the sheer strake butt joint 11 according to H, so that after the round steel 2 across the sheer strake butt joint 11 is installed, the root gap of the round steel butt joint 22 is 0mm to 2mm, so as to facilitate the welding construction between adjacent round steels 2. The spacing H of this embodiment is about 600mm to 1000mm, so that the round steel butt joint 22 and the sheer strake butt joint 11 are staggered by 300mm to 500mm, which is conducive to improving the crack resistance of the sheer strake 1.

[0046] It should be noted that step S3 also includes step S32: processing and grinding the welding groove 21 in the area of ​​the round steel butt joint 22, which is beneficial to improving the welding quality between the round steels 2. Specifically, the welding groove 21 is a symmetrical double-sided groove with a groove angle of 45 degrees.

[0047] Furthermore, if Figure 3 and Figure 5 As shown, step S3 also includes step S33: placing an isolation copper plate 3 between the upper end surface of the sheer top strake 1 and just below each round steel butt joint 22. The isolation copper plate 3 can play an isolation and rapid heat dissipation role, and prevent the weld of the round steel butt joint 22 from contacting the sheer top strake 1. Of course, other isolation members can also be selected, as long as they can isolate the weld of the round steel butt joint 22 from the sheer top strake 1, and they will not be listed here one by one.

[0048] Specifically, an isolation copper plate 3 is placed directly below each round steel butt joint 22, and the isolation copper plate 3 is respectively in close contact with the side top plate 1 and the round steel 2 to avoid a large gap. The thickness of the isolation copper plate 3 is about 2mm to 3mm, and its width is the same as the thickness of the side top plate 1.

[0049] like Figure 5As shown, step S3 also includes step S34: sequentially welding all the round steel butt joints 22 to weld and connect the round steel 2 across the side top strake butt joint 11 and the round steel 2 welded to the side top strake 1. Specifically, when welding each round steel butt joint 22, after one side of the round steel butt joint 22 is welded, the other side of the round steel butt joint 22 is cleaned and ground before welding.

[0050] When welding one side of the round steel joint 22, weld from the middle of the round steel 2 to the outside and the upper part. After welding one side, use a carbon arc gouging to clean the other side of the round steel joint 22. Then, weld the other side of the round steel joint 22. During the welding process, it is necessary to prevent the isolation copper plate 3 from being welded through, and ensure that the isolation copper plate 3 isolates the round steel joint 22 from the side top column 1. The welding quality must be strictly controlled during the welding process to ensure that the round steel joint 22 is completely welded through without welding defects.

[0051] After the welding of the round steel butt joint 22 is completed, the buffer zone of the round steel 2 and the round steel 2 across the butt joint 11 of the sheer strake are symmetrically welded to the sheer strake 1. It should be noted that the buffer zone of the round steel 2 and the round steel 2 across the butt joint 11 of the sheer strake are symmetrically welded to the sheer strake 1 by continuous welding to ensure that there is no welded joint in the fillet weld (the inner and outer welds between the round steel 2 and the sheer strake 1) directly below the round steel butt joint 22, thereby reducing welding defects and stress concentration of the fillet weld and improving welding quality and crack resistance.

[0052] like Figure 5 As shown, the method for constructing the side top strake further includes step S5: grinding the weld surface of the round steel butt joint 22 to be flush with the outer surface of the round steel 2, thereby preventing the weld from being higher than the parent material and preventing stress concentration between the weld and the parent material.

[0053] Furthermore, the method for constructing the side top strake further includes step S6: after standing for a preset time, non-destructive testing is performed on the weld of the round steel butt joint 22. Specifically, the round steel butt joint 22 is placed for 24 hours after welding, and then UT+MT non-destructive testing is performed on it to ensure that there are no welding defects in the weld of the round steel butt joint 22. Of course, the length of the preset standing time and the selection of a suitable flaw detection instrument can also be flexibly adjusted according to actual working conditions. Since UT+MT non-destructive testing is an existing technology, its specific flaw detection process will not be described in detail.

[0054] The above embodiments are only to illustrate the basic principles and characteristics of the present invention. The present invention is not limited by the above embodiments. Without departing from the spirit and scope of the present invention, the present invention may be subject to various changes and modifications, which are within the scope of the present invention. The scope of protection of the present invention is defined by the attached claims and their equivalents.

Claims

1. A method for constructing a sheer strake, characterized in that: The steps include: S1: During the ship block construction stage, the round steel (2) is divided into a middle welding zone and slow-welding zones at both ends along its axial direction, the welding zones of the round steel (2) are symmetrically welded directly above the sheer strake (1), and a non-penetration zone is formed between the round steel (2) and the upper end surface of the sheer strake (1); S2: When the ship's side sections are assembled or closed, weld each side strake butt seam (11); S3: The round steel (2) is installed above each of the side top strake butt seams (11), and the two ends of the round steel (2) across the side top strake butt seams (11) are respectively connected with the ends of the slow welding zone of the round steel (2) on the corresponding side to form a round steel butt seam (22), and each of the round steel butt seams (22) is welded; S4: The slow-welding area of ​​the round steel (2) and the round steel (2) across the butt joint (11) of the sheer strake are both symmetrically welded just above the sheer strake (1); In step S2, after the welding of the sheer strake butt joint (11) is completed, the upper end of the sheer strake butt joint (11) is polished and smoothed to be flush with the upper end surface of the sheer strake (1); Step S3 comprises step S31: measuring the distance H between the two round steel bars (2) on two adjacent side sheer strakes (1), and cutting the round steel bars (2) across the butt joint (11) of the side sheer strakes according to the distance H.

2. The method for constructing a sheer strake according to claim 1, characterized in that: Step S3 also includes step S32: processing and grinding the welding groove (21) in the round steel butt joint (22) area.

3. The method for constructing a sheer strake according to claim 2, characterized in that: Step S3 also includes step S33: placing an isolation copper plate (3) between the upper end surface of the side top column plate (1) and just below each of the round steel butt joints (22).

4. The method for constructing a sheer strake according to claim 3, characterized in that: Step S3 also includes step S34: welding all the round steel butt joints (22) in sequence.

5. The method for constructing a sheer strake according to claim 4, characterized in that: When welding each of the round steel butt joints (22), after the welding of one side of the round steel butt joint (22) is completed, the other side of the round steel butt joint (22) is cleaned and ground before welding.

6. The method for constructing a sheer strake according to claim 1, characterized in that: The method for constructing the side top strake further comprises step S5: grinding the weld surface of the round steel butt joint (22) to be flush with the outer surface of the round steel (2).

7. The method for constructing a sheer strake according to claim 6, characterized in that: The method for constructing the sheer strake further comprises step S6: after standing for a preset time, performing non-destructive testing on the weld of the round steel butt joint (22).

8. The method for constructing a sheer strake according to any one of claims 1 to 7, characterized in that: The slow-welding zone of the round steel (2) and the round steel (2) spanning the butt joint (11) of the sheer strake are symmetrically welded just above the sheer strake (1) by continuous welding.

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