Ultra-large oil tanker bilge construction method
By using the small, medium and large three-level group classification construction method and efficient welding and assembly of the group's position in the construction of some sections of the super-large oil tanker, the problems of high construction difficulty, long construction cycle and high safety risks are solved, and the construction cycle is short, high integration and low construction difficulty are achieved.
Patent Information
- Application Number
- CN202411873823.5
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2024-12-19
- Publication Date
- 2025-03-21
AI Technical Summary
When building a part of the 300,000-ton ultra-large crude oil tanker, the existing technology faces the problems of high construction difficulty, long construction cycle and high safety risks, especially when the three-dimensional scale of segments is large and the internal framework structure is complex.
The three-level grouping and hierarchical construction method is adopted to weld some sections into small and medium-level parts in different areas. 80% of the welding and assembly operations are performed through the group position to reduce the construction volume of medium-level groups, and the outer bottom plate is selected as the large-level tire to avoid sectional rollover and hoisting.
The technical advantages of short construction cycle, high parts integration, low construction difficulty and low safety risks are achieved, reducing the overall cost and risk of segmented construction.
Smart Images
Figure FT_1 
Figure FT_2 
Figure FT_3
Abstract
Description
Technical Field
[0001] The invention belongs to the field of marine ship design and construction, and in particular relates to a method for constructing a bilge of a very large oil tanker. Background Art
[0002] The block construction method is the mainstream process method for building large ships in the world, especially the 300,000-ton very large crude oil tanker VLCC. The use of the block construction method for construction has greatly reduced the ship construction period and construction cost. With the increasing application of the block construction method in recent years and the increasing maturity of the technology, the research on the block construction process method is no longer limited to the research on macro process technologies such as block division and block lifting, but is more inclined to the research on advanced construction methods such as refinement, gridding, space utilization, and process forwarding. A detailed study is conducted on the welding and assembly process of the block modules in the workshop, including the selection of the tire plate according to the structural type and characteristics of the block itself, the evaluation of the welding difficulty, the choice between automatic welding and manual welding, etc., in order to reduce the construction difficulty, improve the assembly and welding efficiency, and reduce costs and increase efficiency.
[0003] According to the current block construction process of mainstream domestic shipyards, the cargo hold structure of 300,000-ton VLCC is divided into sections, and named according to the area to which the sections belong, such as deck sections, side sections, transverse bulkhead sections, longitudinal bulkhead sections, bottom sections and bilge sections. The bilge sections are located in the transition area between the outer bottom plate, inner bottom plate, side outer plate, and inner shell plate of the ship. The bilge sections of conventional VLCCs in the world are usually composed of the following structures, namely, outer bottom plate, bilge arc plate, side outer plate, side horizontal girder, bilge rib plate, inner shell, inclined inner shell, side longitudinal girder, inner bottom plate, and the structure is very complex. When the bilge sections are completed, they usually form a super-large three-dimensional section with a length of about 11m, a width of about 9m, a height of about 8.5m, and a weight of about 110 tons; its characteristics are that the length, width and height of the sections are large in three dimensions, and the internal frame structure is relatively complex. No matter which plane is selected as the tire plate, it is difficult to construct. Summary of the invention
[0004] In order to solve the above problems, the present invention provides a method for building a bilge of a very large oil tanker, and the technical solution adopted is: A method for constructing the bilge of a very large oil tanker, wherein the bilge segment parts are welded into small groups in different areas, forming four small groups with high integration and two middle groups, the four small groups are the bilge arc plate group, the inner bottom three-dimensional group, the side bottom longitudinal girder group, and the horizontal girder three-dimensional group, and the two middle groups are the side outer plate middle group and the inclined inner shell three-dimensional middle group. The specific operation is as follows: S1: Establish the bilge arc plate group After the bilge arc plate is bent in the bending workshop, it is transported to the small group site, where the bilge arc plate is used as the small group stand plate, and the half-stop bracket is welded and assembled, and then the bilge keel is turned over and assembled to form the bilge arc plate small group stand, which is then transported to the large assembly site for subsequent installation.
[0005] S2: Establish rib plane group The bilge rib plate is welded at the group vertical plane site to form a group vertical tire plate, and then the stiffeners, arc flanges, brackets and other auxiliary structures on it are welded to form a rib plate plane group vertical, which is then transported to the inclined inner shell center assembly site for subsequent installation.
[0006] S3: Establish the inner bottom three-dimensional group The side bottom longitudinal girder group is a semi-three-dimensional structure composed of multiple groups assembled twice. The longitudinal girder plate, double bottom rib plate and inner bottom plate are used as flat tires, and the respective auxiliary structures such as auxiliary reinforcement ribs and bracket flanges are welded to form the longitudinal girder group, inner bottom three-dimensional group and double bottom rib flat group. Then, the inner bottom plate is used as the flat tire plate, and the double bottom rib plate and the side bottom longitudinal girder are installed for the second time to form the inner bottom semi-three-dimensional group, which is transported to the inclined inner shell three-dimensional middle assembly site for preparation for subsequent installation.
[0007] S4: Establish a three-dimensional group of horizontal beams The horizontal girder three-dimensional group structure is a semi-three-dimensional structure made of multiple groups assembled twice. The horizontal girder panels, side ribs and inner shell plates are used as group structure base plates, and the attached stiffeners and brackets are welded on them to form three groups of horizontal girder, side ribs and inner shell. The horizontal girder is then turned over and used as the base plate, and the side ribs and inner shell group plates are welded to form a horizontal girder three-dimensional group structure, which is then transported to the middle assembly site of the inclined inner shell for subsequent installation.
[0008] S5: Establish the side shell assembly At the middle assembly site, the side outer plate is welded automatically to complete the panel welding to form the middle assembly plate, and then the attached outer plate longitudinal bones and outer plate PMA horizontal girders are assembled to form the side outer plate middle assembly, which is then transported to the large assembly site for subsequent installation.
[0009] S6: Establish the oblique inner shell solid assembly First, the inner shell plate is assembled on the flat tire, and the inner shell longitudinal bones and reinforcing flat irons and other auxiliary components are installed. Then, it is hoisted to the pillar tire site. The pillar tire plate is formed by the pillar tire, inner bottom three-dimensional group assembly and horizontal girder three-dimensional group assembly project. Then, the rib plate flat group assembly is installed to form the inclined inner shell three-dimensional middle assembly, which is then hoisted to the large assembly site for subsequent installation.
[0010] S7: With the outer bottom plate as the large assembly plate, the outer bottom plate splicing and outer bottom longitudinal bone welding are completed in a professional automated assembly and welding workshop, and then it is transferred to the large assembly position. As the last large assembly plate, the bilge arc plate group is assembled first, and then the inclined inner shell three-dimensional mid-assembly is turned over and installed on the plate, and finally the side outer plate mid-assembly is hoisted to complete the construction of the entire bilge section.
[0011] In the above-mentioned method for building the bilge of a very large oil tanker, further, the whole process of splicing and rib pressing in step S5 is carried out in an automated assembly and welding workshop.
[0012] Compared with the same type of segmented construction method, the construction method of the present invention has the technical advantages of short construction period, high parts integration, low construction difficulty and low safety risk.
[0013] Firstly, the present invention adopts a small, medium and large three-level assembly and hierarchical construction method, which gives full play to the fact that there are many small-scale assembly construction sites and construction can be carried out simultaneously in multiple sites. The medium and large assembly sites have strong construction capacity and large lifting capacity, but the resources are scarce. By taking advantage of the advantages and avoiding the disadvantages, the general principle of moving the process forward is followed, and 80% of the welding and assembly work is moved forward to the small-scale site, reducing the construction volume of the medium and large assemblies, shortening the period of segmentation occupying the large assembly site, and improving the efficiency of segmented construction as a whole.
[0014] Secondly, as mentioned above, the bilge segments are larger in three dimensions than conventional segments, so there is no obvious problem in choosing which base surface to use as the large assembly tire plate for construction. In the past, major shipyards used the side outer plate as the tire plate for bilge segment construction, and the segments needed to be turned over during the dock hoisting stage. The construction method of the present invention selects the outer bottom plate as the tire plate to avoid the large assembly of the segments and then entering the dock for folding and turning over. There is a great risk in the engineering of turning over and hoisting the segments of more than 200 tons, and the present invention greatly reduces the construction risk.
[0015] Thirdly, the most important thing in the construction method of the present invention is the establishment of the three-dimensional assembly of the inclined inner hull. In the past, when the bilge sections were constructed in shipyards, the bilge ribs were usually assembled in a flat group, the horizontal girders were assembled in a three-dimensional group, and the inner bottom was assembled in a three-dimensional group and directly transported to the large assembly site for installation. The inclined inner hull reinforcement panels were also directly transported to the large assembly site for assembly after being pressed, which greatly increased the construction workload and construction period of the large assembly site. The present invention increases the three-dimensional assembly construction stage of the inclined inner hull, integrates the bilge ribs, the inner bottom plate, and the horizontal girders in advance, which also complies with the design principle of moving the process forward and reduces the large assembly construction workload. At the same time, the application of this method also avoids the problem of facing a large number of upward welding problems that are more difficult to weld, and it also plays a great role in improving welding quality and reducing construction difficulty. BRIEF DESCRIPTION OF THE DRAWINGS
[0016] Figure 1 This is a schematic diagram of the erect structure of the bilge arc plate group; Figure 2 It is a schematic diagram of the vertical structure of the rib plate plane group; Figure 3 It is a schematic diagram of the three-dimensional structure of the inner bottom group; Figure 4 It is a schematic diagram of the vertical structure of the horizontal truss three-dimensional group; Figure 5 It is a schematic diagram of the assembled structure in the side outer plate; Figure 6 It is a schematic diagram of the assembled structure in the oblique inner shell stereo; Figure 7 It is a schematic diagram of the large assembly structure; Among them, 1- bilge keel, 2- half bracket, 3- bilge arc plate, 4- stiffener, 5- bilge rib, 6- bracket, 7- double bottom rib, 8- inner floor, 9- longitudinal girder, 10- side rib, 11- horizontal girder splicing, 12- inner shell, 13- outer plate longitudinal, 14-PMA, 15- rib plane group, 16- horizontal girder three-dimensional group, 17- inner bottom three-dimensional group, 18- inclined inner shell rib, 19- outer bottom plate, 20- bilge arc plate group, 21- side outer plate middle assembly, 22- inclined inner shell three-dimensional middle assembly. DETAILED DESCRIPTION
[0017] The present invention will be further described in conjunction with the accompanying drawings.
[0018] A method for constructing a bilge of a very large oil tanker, wherein in the first stage, a group of people construct the bilge.
[0019] During this stage, four highly integrated sub-groups will be completed, namely the bilge arc plate sub-group, the rib plate plane sub-group, the inner bottom three-dimensional sub-group, and the horizontal girder three-dimensional sub-group.
[0020] 1. The bilge arc plate group is erected, such as Figure 1 As shown, after the bilge arc plate is bent in the bending workshop, it is transported to the small group site, and the bilge arc plate 3 is used as the small group stand plate, and the half-stop bracket 2 is welded and assembled, and then the bilge keel 1 is turned over and assembled to form the bilge arc plate small group stand, which is then transported to the large assembly site for subsequent installation.
[0021] 2. Rib plane group is set up, such as Figure 2 As shown, the bilge rib 5 is welded at the group vertical plane site to form a group vertical tire plate, and then the reinforcing rib 4, arc flange, bracket 6 and other auxiliary structures thereon are welded to form a rib plane group vertical, which is then transported to the inclined inner shell for assembly in preparation for subsequent installation.
[0022] 3. The inner bottom three-dimensional group is erected, such as Figure 3As shown, the inner bottom three-dimensional group is a semi-three-dimensional structure composed of multiple groups assembled twice, with longitudinal girders 9, double bottom ribs 7, and inner bottom plates 8 as flat tires, and their respective auxiliary structures such as auxiliary reinforcement ribs and bracket flanges are welded to form longitudinal girders, inner bottom three-dimensional groups and double bottom rib flat groups. The inner bottom plate is then used as a flat tire plate, and the double bottom ribs and the side bottom longitudinal girders are installed for a second time to form the inner bottom semi-three-dimensional group, which is then transported to the inclined inner shell middle group for subsequent installation.
[0023] 4. Horizontal truss three-dimensional group, such as Figure 4 As shown, the horizontal girder stereoscopic subassembly is formed by turning over the horizontal girder panels 11 as the tire plates, welding the side ribs 10 and the inner shell plates 12, forming the horizontal girder stereoscopic subassembly, and transporting it to the inclined inner shell for assembly, ready for subsequent installation.
[0024] The second phase is the central assembly and construction.
[0025] In the bilge construction method of the present invention, the bilge section will form two middle assemblies, namely the side outer plate middle assembly 21 and the inclined inner shell three-dimensional middle assembly.
[0026] 1. Assembled in the side shell, such as Figure 5 As shown in the figure, at the middle assembly site, the side outer plate is welded by automatic welding to form the middle assembly plate, and then the outer plate longitudinal bones 13 and the outer plate PMA14 horizontal girders attached thereto are assembled to form the side outer plate middle assembly 21, which is then transported to the large assembly site for standby use. The whole process of plate splicing and rib pressing is carried out in the automated assembly and welding workshop, which greatly improves the construction efficiency.
[0027] 2. Assemble the oblique inner shell in a three-dimensional space, such as Figure 6 As shown, firstly, the inner shell plate is assembled on the flat tire, and the inner shell longitudinal bones and reinforced flat iron and other auxiliary components are installed, and then hoisted to the support tire site, and the support tire plate is formed between the support tire and the inner bottom three-dimensional group 17 and the horizontal truss three-dimensional group 16, and then the rib plate flat group 15 is installed to form the inclined inner shell three-dimensional middle assembly. Hoisted to the large assembly site for subsequent installation.
[0028] The third stage: large assembly construction The bilge section is assembled in large pieces, such as Figure 7 As shown, the outer bottom plate 19 is the large assembly plate. The outer bottom plate splicing and outer bottom longitudinal bone welding are completed in a professional automated assembly and welding workshop, and then transferred to the large assembly position. As the last large assembly plate, the bilge arc plate sub-assembly 20 is assembled first, and then the inclined inner shell three-dimensional middle assembly 22 is turned over and installed on the plate, and finally the side outer plate middle assembly 21 is hoisted to complete the construction of the entire bilge section.
Claims
1. A method for constructing a bilge of a very large oil tanker, characterized in that: The bilge segment parts are welded into small groups in different areas, forming four small groups with high integration and two middle assemblies. The four small groups are the bilge arc plate small group (20), the rib plate plane small group (15), the inner bottom three-dimensional small group (17), and the horizontal girder three-dimensional small group (16). The two middle assemblies are the side outer plate middle assembly (21) and the inclined inner shell three-dimensional middle assembly (22). The specific operations are as follows: S1: Establish the bilge arc plate group After the bilge arc plate is bent in the bending workshop, it is transported to the small group site, and the bilge arc plate (3) is used as the small group stand plate, and the half-stop bracket (2) is welded and assembled, and then the bilge keel (1) is turned over and assembled to form a bilge arc plate small group stand, which is then transported to the large assembly site for subsequent installation; S2: Establish rib plane group The bilge rib plate (5) is welded at the small-group vertical plane site to form a small-group vertical tire plate, and then the stiffener (4), arc flange, bracket (6) and other auxiliary structures thereon are welded to form a rib plate plane small-group vertical, which is then transported to the inclined inner shell center vertical assembly site to prepare for subsequent installation; S3: Establish the inner bottom three-dimensional group The side bottom longitudinal girder sub-structure is a semi-stereoscopic structure composed of multiple sub-structures assembled twice. The longitudinal girder plate (9), double bottom rib plate (7) and inner bottom plate (8) are respectively used as flat bases, and the respective attached reinforcing ribs and bracket flanges and other attached structures are welded to form the longitudinal girder sub-structure, the inner bottom stereoscopic sub-structure and the double bottom rib flat base. Then, the inner bottom plate is used as the flat base plate, and the double bottom rib plate and the side bottom longitudinal girder are installed twice to form the inner bottom semi-stereoscopic sub-structure, which is then transported to the oblique inner shell stereoscopic center assembly site for subsequent installation. S4: Establish a three-dimensional group of horizontal beams The horizontal girder three-dimensional group is a semi-three-dimensional structure formed by secondary assembly of multiple groups. The horizontal girder plate (11), the side rib plate (10) and the inner shell plate (12) are respectively used as the group plate, and the attached reinforcing ribs and brackets are welded thereon to form three groups of horizontal girder, side rib plate and inner shell. Then, the horizontal girder plate (11) is turned over as the plate, and the side rib plate (10) and the inner shell plate (12) are welded to form the horizontal girder three-dimensional group, which is then transported to the middle assembly site of the inclined inner shell for subsequent installation. S5: Establish the side shell assembly At the mid-assembly site, the side shell plates are welded by automatic welding to form a mid-assembly plate, and then the shell plate longitudinal bones (13) and the shell plate PMA (14) horizontal girders attached thereto are assembled to form the side shell plate mid-assembly, which is then transported to the main assembly site for subsequent installation. S6: Establish the oblique inner shell solid assembly First, the inner shell plate is assembled on the flat surface, and the inner shell longitudinal bones and reinforced flat iron and other auxiliary components are installed, and then hoisted to the support site. The support plate is formed by the support and inner bottom three-dimensional group and horizontal truss three-dimensional group engineering, and then the rib plate flat group is installed to form the inclined inner shell three-dimensional middle assembly, which is hoisted to the large assembly site for subsequent installation; S7: With the outer bottom plate as the large assembly plate, the outer bottom plate splicing and outer bottom longitudinal bone welding are completed in a professional automated assembly and welding workshop, and then it is transferred to the large assembly position. As the last large assembly plate, the bilge arc plate group is assembled first, and then the inclined inner shell three-dimensional mid-assembly is turned over and installed on the plate, and finally the side outer plate mid-assembly is hoisted to complete the construction of the entire bilge section.
2. A method for constructing a bilge of a very large oil tanker according to claim 1, characterized in that: The whole process of panel assembly and rib pressing in step S5 is carried out in an automated assembly and welding workshop.