阅读说明：本技术 江海直达船的舱口角隅结构 (Hatch corner structure of river-sea direct ship ) 是由 甘进 高梓昂 吴卫国 王一雯 汪舟 于 2020-12-19 设计创作，主要内容包括：本发明提供一种江海直达船的舱口角隅结构,包括角隅基体以及设置在所述角隅基体上的裂纹萌生抑制区、复合区、阻裂槽以及表面延展区；其中,角隅基体上具有一弧形侧面,在弧形侧面上具有一扇形分块；裂纹萌生抑制区一体成型在角隅基体的扇形分块中；复合区包括设置在裂纹萌生抑制区靠近底部处的多个第一沟槽；阻裂槽区包括沿裂纹萌生抑制区的弧长方向设置的弧形阻裂槽,阻裂槽区与裂纹萌生抑制区连接；以及表面延展区包括设置在角隅基体上的多个第二沟槽,表面延展区与阻裂槽区远离裂纹萌生抑制区的一侧连接。本发明能有效提高江海直达船舱口角隅的疲劳性能,延长其疲劳寿命,提升江海直达船的疲劳可靠性。(The invention provides a hatch corner structure of a ship capable of directly passing through the river and the sea, which comprises a corner substrate, and a crack initiation inhibition area, a composite area, a crack arrest groove and a surface extension area which are arranged on the corner substrate; wherein, the corner substrate is provided with an arc side surface, and the arc side surface is provided with a fan-shaped block; the crack initiation inhibition area is integrally formed in the fan-shaped blocks of the corner matrix; the composite zone comprises a plurality of first grooves arranged at the position, close to the bottom, of the crack initiation inhibition zone; the crack resistance groove area comprises an arc-shaped crack resistance groove arranged along the arc length direction of the crack initiation inhibition area, and the crack resistance groove area is connected with the crack initiation inhibition area; and the surface extension area comprises a plurality of second grooves arranged on the corner substrate, and the surface extension area is connected with one side of the crack resistance groove area far away from the crack initiation inhibition area. The method can effectively improve the fatigue performance of the hatch corner of the river-sea direct ship, prolong the fatigue life of the ship and improve the fatigue reliability of the river-sea direct ship.)

1. A hatch corner structure of a ship through rivers and seas is characterized by comprising a corner substrate, and a crack initiation inhibition area, a composite area, a crack arrest groove and a surface extension area which are arranged on the corner substrate; wherein the content of the first and second substances,

a corner substrate for providing support for the crack initiation inhibition zone, the recombination zone, the crack arrest channel zone and the surface extension zone, the corner substrate having an arcuate side surface with a segment thereon;

a crack initiation suppression zone for suppressing initiation of cracks at a corner free edge, the crack initiation suppression zone being integrally formed in a segment of a corner substrate;

a composite zone for slowing crack propagation, the composite zone comprising a plurality of first grooves disposed near a bottom of the crack initiation suppression zone;

the crack resistance groove area is used for relieving the stress concentration degree of the tip of a crack, the crack resistance groove area comprises an arc-shaped crack resistance groove arranged along the arc length direction of the crack initiation inhibition area, and the crack resistance groove area is connected with the crack initiation inhibition area; and

a surface extension for increasing the ductility of a surface of a corner substrate, the surface extension including a second plurality of grooves disposed on the corner substrate, the surface extension connecting a side of the crack stop groove region distal from the crack initiation inhibition zone.

2. The hatch corner structure of a ship through the river and sea according to claim 1, wherein the crack initiation suppression area is treated by a shot peening process after being integrally formed in the sectoral block.

3. The hatch corner structure of a direct ship from river to sea according to claim 2, characterized in that the parameters selected for the shot blasting process are: the air pressure is 2-4bar, the inflow is 18-35kg/min, the coverage rate is 100%, cast steel shot is adopted as the shot, and the diameter of the cast steel shot is 0.5-1 mm.

4. The hatch corner structure of a ship through which sea and river are considered according to claim 2, wherein the corner substrate comprises a first side, a second side, a third side and a fourth side which are vertically connected in this order, wherein the first side and the fourth side are connected by the arc-shaped side, the first side has a length of W1, the fourth side has a length of W2, and the crack initiation suppression area has an outer diameter R₂Greater than 0.25 (W)₁+W₂) And not less than 0.5 (W)₁+W₂)。

5. A ship as claimed in claim 4Characterized in that the inner arc radius of the composite zone is R₁The outer arc radius of the surface extension area is R₃Wherein R is₁Length of 0.5(R + R)₂)，R₃Has a length of (2R)₂-R₁) Wherein r is the inner diameter of the crack initiation suppression region.

6. The hatch corner structure of a direct sea-going ship according to claim 1, wherein an arc length of the crack initiation suppression area is smaller than an arc length of the arc-shaped side surface.

7. The hatch corner structure of a direct ship from river to sea according to claim 1, characterized in that the radian of the crack initiation suppression zone is 80-100 °, the radians of the composite zone and the surface extension zone are both 25-35 °, and both are located at the middle position of the arc circumference of the sector area where they are located.

8. The hatch corner structure of a direct sea-going ship according to claim 1, wherein the groove depth h of the crack preventing groove is not more than 0.2b, wherein b is the thickness of the corner substrate.

9. The hatch corner structure of a direct sea-going ship according to claim 1, wherein the depth of each of the first and second grooves is not more than 0.01b, the width of each of the first and second grooves is not more than 0.2mm, and the distance between every two first grooves and the distance between every two second grooves are not less than 0.1mm, wherein b is the thickness of the corner substrate.

10. The hatch corner structure of a direct ship from river to sea according to claim 1, wherein the notches of the first groove, the second groove and the anti-crack groove are all located on the same plane, and the depth directions of the first groove, the second groove and the anti-crack groove are all perpendicular to the radial direction of the arc-shaped side surface.

Technical Field

The invention belongs to the technical field of ship and ocean engineering, and particularly relates to a hatch corner structure of a river-sea direct ship.

Background

As the ship is influenced by complex and frequent external loads for a long time in the process of sailing, the corner structure of the ship hatch is influenced accordingly and is always in a high-low stress alternating state, so that the ship is easy to crack and has a structural failure phenomenon.

In the whole service process of the ship, the ship is influenced by alternating loads from river sections, sea sections and the like for a long time, so that the corner structures are always in an alternating high-low stress state, and the corner structures of the ship body are easy to crack and have the phenomenon of structural damage. With the accumulation of fatigue damage, the service life of the ship hull structure is seriously affected, so that the research on the technology and the method for improving and increasing the fatigue life of the ship hull corner structure is very important.

Disclosure of Invention

The invention aims to provide a hatch corner structure of a river-sea direct ship, aiming at the defects of the prior art, and the corner structure can improve the fatigue resistance of the corner structure of a ship body.

In order to solve the technical problems, the invention adopts the following technical scheme:

a hatch corner structure of a ship through river and sea comprises a corner substrate, and a crack initiation inhibition area, a composite area, a crack arrest groove and a surface extension area which are arranged on the corner substrate; wherein the content of the first and second substances,

the corner substrate is used for providing support for the crack initiation inhibition area, the recombination area, the crack resistance groove area and the surface extension area, and the corner substrate is provided with an arc-shaped side surface and a fan-shaped block on the arc-shaped side surface;

a crack initiation suppression zone for suppressing initiation of cracks at a corner free edge, the crack initiation suppression zone being integrally formed in a segment of a corner substrate;

a composite zone for slowing crack propagation, the composite zone comprising a plurality of first grooves disposed near a bottom of the crack initiation suppression zone;

the crack resistance groove area is used for relieving the stress concentration degree of the tip of a crack, the crack resistance groove area comprises an arc-shaped crack resistance groove arranged along the arc length direction of the crack initiation inhibition area, and the crack resistance groove area is connected with the crack initiation inhibition area; and

a surface extension for increasing the ductility of a surface of a corner substrate, the surface extension including a second plurality of grooves disposed on the corner substrate, the surface extension connecting a side of the crack stop groove region distal from the crack initiation inhibition zone.

Further, after the crack initiation inhibition area is integrally formed in the fan-shaped blocks, the crack initiation inhibition area is processed by adopting a shot peening strengthening process.

Further, the parameters selected by the shot blasting process are as follows: the air pressure is 2-4bar, the inflow is 18-35kg/min, the coverage rate is 100%, cast steel shot is adopted as the shot, and the diameter of the cast steel shot is 0.5-1 mm.

Further, the corner base comprises a first side surface, a second side surface, a third side surface and a fourth side surface which are vertically connected in sequence, wherein the first side surface and the fourth side surface are connected through the arc-shaped side surface, and the length of the first side surface is W₁The length of the fourth side is W₂Outer diameter R of crack initiation suppression region₂Greater than 0.25 (W)₁+W₂) And not less than 0.5 (W)₁+W₂)。

Further, the inner arc radius of the compound area is R₁The outer arc radius of the surface extension area is R₃Wherein R is₁Length of 0.5(R + R)₂)，R₃Has a length of (2R)₂-R₁) Wherein r is the inner diameter of the crack initiation suppression region.

Further, the arc length of the crack initiation inhibition zone is smaller than the arc length of the arc-shaped side surface.

Further, the radian of the crack initiation inhibition area is 80-100 degrees, the radians of the composite area and the surface extension area are both 25-35 degrees, and the composite area and the surface extension area are both positioned at the middle part of the arc circumference of the sector area where the composite area and the surface extension area are positioned.

Further, the groove depth h of the crack stop groove is not more than 0.2b, wherein b is the thickness of the corner substrate.

Furthermore, the depth of each of the first grooves and the depth of each of the second grooves are not greater than 0.01b, the width of each of the first grooves and the width of each of the second grooves are not greater than 0.2mm, the distance between every two first grooves and the distance between every two second grooves are not less than 0.1mm, wherein b is the thickness of the corner substrate.

Furthermore, the notches of the first groove, the second groove and the crack-resistant groove are all located on the same plane, and the depth directions of the first groove, the second groove and the crack-resistant groove are all perpendicular to the radial direction of the arc-shaped side face.

Compared with the prior art, the invention has the beneficial effects that: the hatch corner free edge stress-enhanced crack initiation suppression device is provided with the crack initiation suppression area which is formed through shot peening strengthening treatment, the crack initiation suppression area is connected with the hatch corner free edge so that a plastic layer is generated on the surface of the hatch corner free edge to strengthen the surface hardness of the hatch corner free edge, and a residual compressive stress field is introduced into the crack initiation suppression area, so that the initiation and the expansion of cracks on the corner free edge can be effectively delayed; the composite region is a fan-shaped groove milled on the crack initiation inhibition region formed by shot peening treatment, the composite region has the function of a residual compressive stress field, and the fan-shaped groove zone on the surface can improve the ductility of the surface, reduce the stress concentration degree of the surface and block crack propagation; when the crack resistance groove area inevitably expands to the crack resistance groove area, the stress concentration at the tip of the crack is relieved by the crack resistance groove area, the crack is induced to expand along the boundary of the crack resistance groove area, and the expansion path of the crack is changed, so that the expansion rate of the crack is reduced; the surface extension area is a fan-shaped groove belt milled on the surface of the corner substrate to increase the ductility of the surface of the corner structure and reduce the stress concentration degree of the surface, so that the expansion of the crack is slowed down, the crack is induced to expand along the groove, the expansion path of the crack on the surface is changed, and the expansion of the crack is slowed down; the invention can effectively improve the reliability of the corner structure and can improve the fatigue resistance of the corner structure of the ship body.

Drawings

FIG. 1 is a schematic structural diagram of a corner structure of a river-sea express vessel according to an embodiment of the present invention;

FIG. 2 is an enlarged partial view of a corner structure according to an embodiment of the present invention;

FIG. 3 is a schematic structural diagram of a first trench milled in a composite region/a second trench milled in a surface extension region according to an embodiment of the present invention, where a is a distance between trenches, d is a trench depth, and c is a width;

fig. 4 is a schematic structural diagram of a crack prevention groove according to an embodiment of the present invention.

The corner structure comprises a crack initiation inhibition area 1, a crack initiation inhibition area 2, a composite area 3, a surface extension area 4, a crack resistance groove area 5, a corner substrate 20, a first groove 30, a second groove 40, a crack resistance groove 50, a first side surface 51, a second side surface 52, a third side surface 53, a fourth side surface 54 and an arc-shaped side surface.

Detailed Description

The technical solutions in the embodiments of the present invention will be described clearly and completely with reference to the following embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

It should be noted that the embodiments and features of the embodiments may be combined with each other without conflict.

The present invention is further illustrated by the following examples, which are not to be construed as limiting the invention.

As shown in fig. 1 and 2, the present invention provides a hatch corner structure of a ship through the river and the sea, comprising a corner substrate 5, a crack initiation suppression region 1, a recombination region 2, a crack arrest groove region 4 and a surface extension region 3, which are sequentially arranged on the corner substrate 5. The corner base 5 is made of steel material, and is a block structure including a first side 50, a second side 51, a third side 52, a fourth side 53 and an arc side 54 connecting the first side 50 and the fourth side 53. In use, the second side 51 and the third side 52 of the corner substrate 5 can be fixed to the hatch. In order to improve the fatigue resistance of the corner structure, a fan-shaped block is arranged on the arc-shaped side surface 54 of the corner substrate 5, a crack initiation inhibition area 1 matched with the fan-shaped block in shape and size is integrally formed in the fan-shaped block, and then shot blasting processing is carried out on the crack initiation inhibition area 1, wherein the arc length of the crack initiation inhibition area 1 is smaller than that of the arc-shaped side surface. Wherein, the parameters selected by the shot blasting process are as follows: the air pressure is 2-4bar, the inflow is 18-35kg/min, the coverage rate is 100%, cast steel shot is adopted as the shot, and the diameter of the cast steel shot is 0.5-1 mm. In this embodiment, the parameters selected for the shot blasting process are air pressure 3bar, inflow rate 25kg/min, coverage rate 100%, and the shot is S280 cast steel shot with an average diameter of 0.8 mm. In this embodiment, the arc of the crack initiation suppression zone 1 is 90 °, although in other embodiments it may be selected between 80 ° and 100 ° depending on the actual situation. And then milling a composite area 2 on one side surface of the crack initiation inhibition area 1, specifically, referring to fig. 3, milling a plurality of first grooves 20 on the side surface of the crack initiation inhibition area 1, wherein the plurality of first grooves 20 form the composite area 2, and the composite area 2 is arranged at the bottom of the crack initiation inhibition area 1 and is located at the middle position around the arc of the crack initiation inhibition area 1. As shown in fig. 4, after the compound region 2 is processed, a crack-resistant groove region 4 is milled and formed at the corner substrate 5 near the crack initiation inhibition region, the crack-resistant groove region 4 includes a crack-resistant groove 40 arranged along the arc length direction of the fan-shaped segment, wherein the notch of the crack-resistant groove 40 is on the same side as the notch of the first groove 20. The depth h of the crack stop groove 40 is related to the thickness b of the corner substrate 5, but should not be greater than 0.2b, and the depth direction of the crack stop groove 40 and the depth direction of the first groove 20 are perpendicular to the radial direction of the arc-shaped side surface.

In order to further slow down the crack propagation, the surface extension 3 is milled on the side of the corner base 5 perpendicular to the curved side, the surface extension 3 also being located in the middle of the circumference of the segment in which it is located. Specifically, referring to fig. 3, a plurality of second grooves 30 are milled in the side surface of the corner substrate 5, the second grooves 30 have the same shape and size as the first grooves 20, and specifically, the sizes of the first grooves 20 and the second grooves 30 both satisfy the following condition: the depth d of the first groove 20 and the second groove 30 should be not more than 0.01b, where b is the thickness of the corner substrate, the width c of the first groove 20 and the second groove 30 should be not more than 0.2mm, and the distance between every two first grooves 20 and the distance a between every two second grooves 30 should be not less than 0.1 mm. In order to prevent excessive roughness on the corner substrate 5, the surface extension 3 has an arc of 25 to 35 °, in the present example 30 °, and correspondingly the composite region has an arc of 25 to 35 °, optionally 30 °. In addition, it should be noted that when the groove is machined, it is necessary to note that the milling is not performed within 2mm from the inner and outer arcs of the crack-resistant groove region, respectively. At this point, the corner structure is finished. The crack initiation inhibition zone 1, the crack resistance groove zone 4 and the surface extension zone 3 in the processed corner structure are connected in sequence.

In the finished corner structure, the length of the first side surface 50 of the corner substrate 5 is W₁The length of the fourth side 53 in the corner base 5 is W₂Outer diameter R of crack initiation suppression region 1₂Greater than 0.25 (W)₁+W₂) And not less than 0.5 (W)₁+W₂). Furthermore, the inner arc radius of the recombination zone 2 is R₁The outer arc radius of the surface extension zone 3 is R₃Wherein R is₁Length of 0.5(R + R)₂)，R₃Has a length of (2R)₂-R₁) Wherein r is the inner diameter of the crack initiation suppression region 1. The center radius of the crack-resistant groove area 4 is R₄，R₄Ratio R₂The length is at least t +1mm, wherein t is the width of the crack-resistant groove region 4.

The working principle of the invention is as follows: the crack initiation inhibition area 1 formed by shot blasting process has a larger residual compressive stress field, and can effectively inhibit the initiation of cracks at the free edge of the corner of the hold of a ship from the river to the sea under the alternate action of bearing the large and small loads of the river and the sea. When cracks inevitably initiate, the residual compressive stress field can still inhibit the rate of crack propagation. After the crack propagates to the compound region 2, under the combined action of the residual compressive stress and the groove band of the compound region 2, the residual compressive stress field can inhibit the propagation rate of the crack, the surface groove band of the compound region 2 increases the surface ductility of the corner structure, the local stress concentration degree is reduced due to the improvement of the surface ductility, and the local propagation path of the crack is induced to propagate along the groove, so that the crack is prevented from propagating along the original path on the surface of the corner structure, and the propagation rate of the crack is reduced. When the crack propagates to the crack stop zone 4, the stress concentration at the crack tip is partially released by the geometric transition shape of the crack stop zone 4, and the crack propagation is slowed down. The crack propagation path is blocked, the crack propagation path is induced to propagate for a certain length along the inner arc at the bottom of the crack-resistant groove region 4, then the crack propagation path penetrates through the bottom of the crack-resistant groove region 4 to reach the outer arc and is propagated for a certain length along the outer arc, and the crack penetrates through the crack-resistant groove region 4, so that the original crack propagation path is greatly changed, and the crack propagation rate is greatly slowed down. The surface extension zone 3 functions in the same way as the grooved strip in the recombination zone 2 described above. In conclusion, the hatch corner structure of the direct ship from river to sea can effectively improve the fatigue performance of the hatch corner structure of the direct ship from river to sea, prolong the fatigue life of the direct ship from river to sea, and improve the fatigue reliability of the direct ship from river to sea.

While the invention has been described with reference to a preferred embodiment, it will be understood by those skilled in the art that various changes in form and detail may be made therein without departing from the spirit and scope of the invention.