A method for assembling and hoisting a modular foremast on a ship

Abstract

This invention relates to a method for the modular foremast assembly and overall hoisting on ships. The method includes a modular assembly stage and an overall hoisting stage. The modular foremast structure includes a base, a mast body, and a masttop assembly. In the modular assembly stage, the base, mast body, and masttop assembly are fabricated separately at different sites and transported to the assembly site. The base is hoisted onto the assembly platform. A crane is used to rotate the mast body 90 degrees to a normal position. The mast body is then hoisted onto the base and connected for installation. The masttop assembly is then embedded into the top of the mast body's column, completing the assembly of the modular foremast. In the overall hoisting stage, the weight and center of gravity of the modular foremast are calculated, and a hoisting rack and a three-dimensional hoisting structure are used to achieve the overall hoisting of the modular foremast. This method of the invention involves modular hoisting during construction and pre-assembly on the assembly platform, followed by overall hoisting, thereby achieving modular and complete installation of the equipment and improving construction efficiency.

Description

Technical Field

[0001] This invention relates to shipbuilding, and in particular to a method for assembling and hoisting a modular foremast on a ship. Background Technology

[0002] During shipbuilding, numerous pieces of equipment are often transported in several parts to the shipyard for ease of transport, where they are assembled and installed. Equipment manufacturers often only consider the transportation and hoisting of these parts, neglecting the fact that during the actual shipbuilding process, equipment is installed in the dry dock, consuming crane resources, lengthening the dry dock construction cycle, and, most importantly, involving extensive high-altitude work during bulk hoisting and installation, requiring scaffolding, resulting in low work efficiency and significant safety risks.

[0003] In the construction of certain types of ships, the foremast structure is sometimes assembled before being hoisted as a whole. In current shipbuilding practice, the segmented and modular structures, including the foremast, involve high-altitude operations during component supply and installation. In reality, the mast structure of a ship is delicate and thin, making it impossible to specifically install lifting lugs for hoisting. Using existing technologies and methods often leads to installation difficulties, thus affecting the overall construction efficiency of the ship. In this context, this invention proposes a new assembly method for modular foremasts on ships and a corresponding hoisting method, precisely to solve this installation problem, meet the requirements for rapid and safe installation of the foremast structure, thereby improving installation efficiency and reducing installation risks. Summary of the Invention

[0004] The purpose of this invention is to overcome the shortcomings of the existing technology and provide a method for the modular assembly and overall hoisting of a foremast on a ship. This method addresses the hoisting and installation needs of modular foremasts during construction, allowing for pre-assembly on a platform, achieving modular and complete installation of the equipment, thereby improving construction efficiency.

[0005] To achieve the above-mentioned objectives, the present invention provides the following technical solution:

[0006] A method for assembling and hoisting a modular foremast on a ship, the method comprising a modular assembly stage and an overall hoisting stage, wherein the modular foremast structure includes a base, a mast body, and mast top equipment.

[0007] The component assembly process includes:

[0008] The first step involves manufacturing the base, mast, and mast top equipment separately at different sites, and then transporting them to the main assembly site.

[0009] The second step is to place wooden blocks on the main assembly platform and adjust them to be level. Then, the blocks are hoisted onto the wooden blocks using the lifting lugs on the base. The base is a frustum structure with four lifting lugs arranged along the normal to the center of the frustum on the top surface of the frustum.

[0010] The third step is to use a crane, with the main hook being the lifting rod inside the top of the mast column and the secondary hook being the lifting lugs set on the mast transport frame, to turn the mast 90 degrees to a normal position.

[0011] Fourth step: Without releasing the main hook at the top, disconnect the mast from the transport frame, loosen the secondary hook lifting point on the transport frame, and normally lift the mast onto the base and install it in conjunction with the base.

[0012] Fifth step: Release the main hook of the mast hoisting and remove the crane;

[0013] The sixth step is to embed the mast top device into the top of the mast body to complete the assembly of the modular foremast;

[0014] The overall hoisting process includes:

[0015] Step 7: Calculate the weight and center of gravity of the combined foremast, and use a hoisting rack and three-dimensional gantry structure to achieve the overall hoisting of the combined foremast;

[0016] Step 8: Hang four upper steel wire ropes on the hook of the crane. The four upper steel wire ropes are respectively connected to the lifting lugs on the upper end of the lifting platform. Four lower steel wire ropes are also connected to the lifting lugs on the lower end of the lifting platform. The other ends of the four lower steel wire ropes are respectively connected to the three-dimensional hanging frame. The three-dimensional hanging frame includes a U-shaped frame and a round tube connecting rod. One side of the U-shaped frame has an opening. Four lifting lugs are provided on the top and bottom of the U-shaped frame, respectively.

[0017] Step 9: The U-shaped frame enters from the side of the mast through the opening side until the U-shaped frame is located at the center of the mast. The lower steel wire rope is connected to the four lifting lugs above the U-shaped frame. The four lifting lugs below the U-shaped frame are respectively connected to the round tube connecting rods. The other ends of the four round tube connecting rods are respectively connected to the lifting lugs on the base.

[0018] Step 10: Install the sealing crossbar, which is installed on one side of the opening of the U-shaped frame to restrain the mast within the U-shaped frame;

[0019] Step 11: Start the crane and slowly lift the combined foremast using steel wire ropes, lifting blocks and three-dimensional lifting frames, and install the combined foremast onto the hull section in place;

[0020] Step 12: After hoisting is completed, first remove the sealing crossbar and wire rope, and then remove the U-shaped frame in the opposite direction to complete the overall hoisting of the modular foremast.

[0021] In the method for assembling and hoisting a modular foremast on a ship according to the present invention, the third step uses the jacks embedded in the top column and the lugs on the transport frame to turn the mast over.

[0022] In the present invention, a method for assembling and hoisting a modular foremast on a ship, the third step describes a column in the middle of the mast body, on which multiple masts are fixed at an incline. Electrical equipment, including wires, cables and lights, is installed on the masts. The center of gravity of the mast body is located at the upper part of the column body near the mast.

[0023] In the present invention, a method for assembling and hoisting a modular foremast on a ship, the U-shaped frame in the eighth step is a rectangular frame structure with three steel sections forming a U-shaped inner groove. The main structural dimension of the U-shaped frame is larger than that of the mast column and is at least 1 meter larger.

[0024] In the present invention, a method for assembling and hoisting a modular foremast on a ship, the three steel sections are two side steel sections and a bottom steel section. The two side steel sections are fixed parallel and vertically to both ends of the bottom steel section. Short plate steel sections are also vertically fixed at the ends of the two side steel sections. The gap between the short plate steel sections is a reserved U-shaped inner groove opening as a U-shaped frame opening.

[0025] In a method for assembling and hoisting a modular foremast on a ship according to the present invention, an elbow plate is provided at the angle between the short plate steel and the side steel, and a diagonal bracing is provided at the angle between the side steel and the bottom steel.

[0026] In the present invention, a method for assembling and hoisting a modular foremast on a ship is further provided, with lifting lugs fixed on both the upper and lower surfaces of the two sides of the steel profiles, and four lifting lugs provided on the upper and lower surfaces of the U-shaped frame. The arc of the line connecting the lifting points formed by the four lifting lugs is concentric with the arc of the line connecting the four lifting lugs on the top surface of the truncated cone of the base, and the direction of the main lifting lug is consistent with the direction of the corresponding main lifting lug on the base platform.

[0027] In a method for assembling and hoisting a modular foremast on a ship according to the present invention, a circular hole is further provided on the outer end face of the short plate steel near the opening side, and the circular tube connecting rod is a circular tube with sealing plates on both sides, with lifting lugs provided on the sealing plates at both ends, and the main plate direction of the lifting lugs at both ends is consistent.

[0028] In the present invention, a method for assembling and hoisting a modular foremast on a ship, the vertical projection of the circular tube connecting rod is greater than the height of the center of gravity from the lifting lug on the base, and is greater than 1 meter.

[0029] In the present invention, a method for assembling and hoisting a modular foremast on a ship, the spacing between the lifting lugs below the hoisting rack is greater than the size of the mast's projected surface, and a safety margin of at least 1m is reserved around the projected edge of the mast and the inner wall of the U-shaped frame.

[0030] In the present invention, a method for assembling and hoisting a modular foremast on a ship, in the tenth step, the main body of the sealing crossbar is a round tube, with sealing plates at both ends of the round tube, square plates installed on the sealing plates, and round holes opened on the square plates. The round holes are of the same size on the short plate steel, and the distance between the centers of the round holes is equal. The sealing crossbar is connected and fixed to the U-shaped frame by bolts and nuts.

[0031] Based on the above technical solution, the modular foremast assembly and overall hoisting method of the present invention on ships has achieved the following technical effects after being applied to actual ships:

[0032] 1. The modular foremast assembly and overall hoisting method of the present invention can solve the separate hoisting and installation requirements of modular foremast components during the construction process. It allows for pre-assembly on the main assembly platform, thereby meeting the trend of modular equipment construction and the requirement of complete installation. The method of modular assembly and overall hoisting improves the construction efficiency and quality of ships.

[0033] 2. In the modular foremast assembly and overall hoisting method of the present invention, a special three-dimensional hoisting frame and hoisting rack are set up to take into account the structural characteristics of the modular foremast. The three-dimensional hoisting frame is a side insertion type, which avoids the need to insert it from the top and make the frame very large in order to avoid the problem of the mast structure. The tooling body is small and the manufacturing cost is low.

[0034] 3. The three-dimensional gantry in the modular foremast assembly and overall hoisting method of the present invention is detachable, reusable, simple to operate, and cost-saving, achieving the goal of reducing costs and increasing efficiency in the shipbuilding process. Attached Figure Description

[0035] Figure 1 This is a schematic diagram of the assembly process of the combined foremast of the present invention.

[0036] Figure 2 This is a schematic diagram of the overall hoisting method for the combined foremast of the present invention.

[0037] Figure 3 This is a schematic diagram of the three-dimensional hanger structure in this invention. Detailed Implementation

[0038] The following detailed description, in conjunction with the accompanying drawings, provides a more comprehensive understanding of the application process of the present invention's combined foremast on a ship, but this should not be construed as limiting the scope of protection of the present invention.

[0039] In shipbuilding, modular foremasts are supplied as loose components. Due to the special structure and materials of the equipment, additional lifting lugs cannot be added, and the default method is to install them loosely. This increases scaffolding work and takes up more time using cranes, lengthening the dock cycle and hindering construction efficiency. If the modular foremast is assembled in advance, the high center of gravity of the foremast means that directly lifting it using the lifting lugs on the base would pose a risk of tipping and swaying, resulting in significant safety hazards.

[0040] like Figure 1 As shown, this invention relates to an assembly and hoisting method for a modular foremast on a ship. The modular foremast consists of three parts: a base 1, a mast body 2, and a mast top device 3. The base 1 has a frustum-shaped structure with four lifting lugs distributed along the normal direction on the platform. The mast body 2 includes a column and a mast. The mast body is transported in a sideways position and installed by flipping it over using a hoist located inside the top of the column. The mast is at an upward angle. The mast top device 3 is inserted into the top of the column in the mast body 1. The mast top device 3 can only be installed after the mast body 2 is erected. Furthermore, the mast top device itself does not have lifting lugs and cannot be equipped with lifting points; it can only be transported by lifting as a whole. Figure 1 After the assembly of the combined foremast is completed, the height of the center of gravity 8 of the combined foremast is higher than the height of the lifting lugs on the base 3. This is a stability factor that must be considered during hoisting.

[0041] The present invention relates to a method for assembling and hoisting a modular foremast in separate sections, comprising a section for assembling the sections separately and a section for hoisting the entire assembly.

[0042] like Figure 2 As shown, the assembly process includes:

[0043] The first step involves manufacturing the base 1, mast 2, and mast top device 3 separately at different sites, and then transporting them to the main assembly site.

[0044] The second step is to place the wooden blocks 10 on the main assembly platform and adjust them to be level. Then, the blocks are hoisted onto the wooden blocks 10 using the lifting lugs on the base 1. The base 1 is a frustum structure with four lifting lugs arranged along the normal to the center of the frustum on the top surface of the frustum.

[0045] The third step involves using a crane, with the main hook being the boom inside the top column of mast 2 and the secondary hook being the lifting lugs on the mast's transport frame, to flip mast 2 90 degrees. After flipping, mast 2 changes from a horizontal position on the transport frame to a vertical position. Mast 2 has a column in its middle section, with multiple masts fixed at an angle on the column. Electrical equipment, including wires, cables, and lights, is mounted on the masts. This top-heavy structure causes the center of gravity of mast 2 to be located at the upper part of the column, near the masts. This step, using the boom embedded in the top column and the lifting lugs on the transport frame to flip the mast, not only ensures high stability but also guarantees safety.

[0046] Fourth step: Without loosening the main hook at the top, disconnect the mast 2 from the transport frame, loosen the secondary hook lifting point on the transport frame, and normally lift the mast 2 onto the base 1 and connect it with the base 1 to fix the mast 2 on the base 1. At this time, the mast 2 and the base 1 are on the same axis.

[0047] Fifth step: Release the main hook on mast 2 and remove the crane.

[0048] The sixth step is to lift the mast top device 3 onto the top of the mast body 2 and embed the mast top device 3 into the top of the column of the mast body 2. After fixing, the assembly of the combined foremast is completed.

[0049] After the foremast structure is assembled, it needs to be hoisted onto the hull structure, which is the subsequent overall hoisting process.

[0050] like Figure 3 As shown, the overall hoisting process includes:

[0051] Step 7: Calculate the weight of the combined foremast and the position of the center of gravity 8, and use the hoisting rack 6 and the three-dimensional gantry 9 to achieve the overall hoisting of the combined foremast.

[0052] Step 8: Four upper steel wire ropes 5 are hung on the hook of the gantry crane 4, which serves as the crane. The four upper steel wire ropes 5 are respectively connected to the lifting lugs on the upper end of the lifting platform 6. Four lower steel wire ropes 7 are connected to the lifting lugs on the lower end of the lifting platform 6. The other ends of the four lower steel wire ropes 7 are respectively connected to the three-dimensional lifting frame 9. The three-dimensional lifting frame 9 includes a U-shaped frame 91 and a round tube connecting rod 92. An opening is provided on one side of the U-shaped frame 91. Four lifting lugs are provided on the top and bottom of the U-shaped frame 91, respectively.

[0053] For the three-dimensional hanger 9, the U-shaped frame 91 is a rectangular frame structure formed by three steel sections enclosing a U-shaped inner channel. The main structural dimension of the U-shaped frame 91 is larger than the column dimension of the mast 2, and at least 1 meter larger. Specifically, the three steel sections are the side steel sections and the bottom steel section. The side steel sections are parallel and vertically fixed to both ends of the bottom steel section. Short steel plates are also vertically fixed to the ends of the side steel sections. The gaps between these short steel plates form the openings of the pre-reserved U-shaped inner channel, which serve as the openings of the U-shaped frame 91.

[0054] An elbow plate 95 is provided at the angle between the short steel plate and the side steel plates, and a diagonal bracing is provided at the angle between the side steel plates and the bottom steel plate. Lifting lugs are fixed to the upper and lower surfaces of both ends of the side steel plates. Four lifting lugs are provided on the upper and lower surfaces of the U-shaped frame. The arc of the line connecting the lifting points formed by the four lifting lugs is concentric with the arc of the line connecting the four lifting lugs on the top surface of the frustum of the base, and the direction of the main lifting lug plate is consistent with the direction of the corresponding main lifting lug plate on the base platform.

[0055] A circular hole is provided on the outer end face of the short plate steel near the opening. The circular tube connecting rod is a circular tube with sealing plates on both sides. Lifting lugs are provided on the sealing plates at both ends, and the main plate direction of the lifting lugs at both ends is consistent.

[0056] In the ninth step, the U-shaped frame 91 enters from the side of the mast 2 through its opening until it is located at the center of the mast 2. The lower steel wire rope 7 is connected to the four lifting lugs above the U-shaped frame 91, and the four lifting lugs below the U-shaped frame 91 are respectively connected to the circular tube connecting rods 92. The other ends of the four circular tube connecting rods 92 are respectively connected to the lifting lugs on the base 1. The vertical projection dimension of the circular tube connecting rod 92 is greater than the height of the center of gravity from the lifting lugs on the base 1, and is greater than 1 meter.

[0057] Step 10: Install the sealing crossbar 93. The sealing crossbar 93 is installed on one side of the opening of the U-shaped frame 91 to constrain the mast of the mast body 2 within the U-shaped frame 91. The spacing between the lifting lugs below the hoisting rack 6 is greater than the projected size of the mast, and a safety margin of at least 1m is reserved around the projected edge of the mast and the inner wall of the U-shaped frame to ensure sufficient space and prevent excessive collision and friction during hoisting. The main body of the sealing crossbar 93 is a round tube with sealing plates at both ends. Square plates are installed on the sealing plates, and round holes are opened on the square plates. The round holes are all the same size as the round holes on the short plate steel, and the distance between the centers of the round holes is equal. The sealing crossbar 93 is connected and fixed to the U-shaped frame 91 by bolts and nuts 94. For the U-shaped frame 91, the four lifting rings on it are distributed on the same circumference. The lifting rings 96 on the U-shaped frame 91 form the U-shaped frame lifting ring connection line 98. The four lifting rings on the frustum surface of the base 1 are on the same circumference. The lifting rings on the base form the base lifting ring connection line 95. The base lifting ring connection line 95 and the U-shaped frame lifting ring connection line 98 are coaxial and belong to concentric circles.

[0058] Step 11: Start the crane and slowly lift the combined foremast using the upper wire rope 5, lower wire rope 7, lifting platform 6 and three-dimensional lifting frame 9, and install the combined foremast onto the hull section. Specifically, fix the base 1 of the combined foremast onto the hull section.

[0059] Step 12: After hoisting is completed, first remove the sealing crossbar 93, upper wire rope and lower wire rope, and then remove the U-shaped frame 91 in the opposite direction to complete the overall hoisting of the combined foremast.

[0060] The assembly and hoisting method for a modular foremast on ships of this invention is a hoisting method applicable to novel structures or equipment, and has significant technical reference value. It can solve the hoisting and installation needs of modular foremasts during construction, allowing for pre-assembly on a platform, achieving modular and complete installation, and improving construction efficiency. The three-dimensional hoisting frame is a side-insertion type, avoiding the need for top-insertion and the necessitation of making an extremely large frame to avoid mast structure problems. The tooling body is smaller, resulting in lower manufacturing costs. Furthermore, the hoisting frame is detachable and reusable, simplifying operation, saving costs, and achieving the goal of cost reduction and efficiency improvement.

[0061] The specific embodiments described above further illustrate the technical problems solved by the present invention, the technical solutions, and the beneficial effects. It should be understood that the above descriptions are merely specific embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A method for assembling and hoisting a modular foremast on a ship, characterized in that, The method includes a modular assembly stage and an overall hoisting stage. The combined foremast structure includes a base, mast body, and mast top equipment. The component assembly process includes: The first step involves manufacturing the base, mast, and mast top equipment separately at different sites, and then transporting them to the main assembly site. The second step is to place wooden blocks on the main assembly platform and adjust them to be level. Then, the blocks are hoisted onto the wooden blocks using the lifting lugs on the base. The base is a frustum structure with four lifting lugs arranged along the normal to the center of the frustum on the top surface of the frustum. The third step is to use a crane, with the main hook being the lifting rod inside the top of the mast column and the secondary hook being the lifting lugs set on the mast transport frame, to turn the mast 90 degrees to a normal position. Fourth step: Without releasing the main hook at the top, disconnect the mast from the transport frame, loosen the secondary hook lifting point on the transport frame, and normally lift the mast onto the base and install it in conjunction with the base. Fifth step: Release the main hook of the mast hoisting and remove the crane; The sixth step is to embed the mast top device into the top of the mast body to complete the assembly of the modular foremast; The overall hoisting process includes: Step 7: Calculate the weight and center of gravity of the combined foremast, and use a hoisting rack and three-dimensional gantry structure to achieve the overall hoisting of the combined foremast; Step 8: Hang four upper steel wire ropes on the hook of the crane. The four upper steel wire ropes are respectively connected to the lifting lugs on the upper end of the lifting platform. Four lower steel wire ropes are also connected to the lifting lugs on the lower end of the lifting platform. The other ends of the four lower steel wire ropes are respectively connected to the three-dimensional hanging frame. The three-dimensional hanging frame includes a U-shaped frame and a round tube connecting rod. One side of the U-shaped frame has an opening. Four lifting lugs are provided on the top and bottom of the U-shaped frame, respectively. Step 9: The U-shaped frame enters from the side of the mast through the opening side until the U-shaped frame is located at the center of the mast. The lower steel wire rope is connected to the four lifting lugs above the U-shaped frame. The four lifting lugs below the U-shaped frame are respectively connected to the round tube connecting rods. The other ends of the four round tube connecting rods are respectively connected to the lifting lugs on the base. Step 10: Install the sealing crossbar, which is installed on one side of the opening of the U-shaped frame to constrain the mast within the U-shaped frame; Step 11: Start the crane and slowly lift the combined foremast using steel wire ropes, lifting blocks and three-dimensional lifting frames, and install the combined foremast onto the hull section in place; Step 12: After hoisting is completed, first remove the sealing crossbar and wire rope, and then remove the U-shaped frame in the opposite direction to complete the overall hoisting of the modular foremast.

2. The method for assembling and hoisting a modular foremast on a ship according to claim 1, characterized in that, In the third step, the middle part of the mast is a column, and multiple masts are fixed at an incline on the column. Electrical equipment, including wires, cables and lights, is installed on the masts. The center of gravity of the mast is located at the upper part of the column near the mast.

3. The method for assembling and hoisting a modular foremast on a ship according to claim 2, characterized in that, In the eighth step, the U-shaped frame is a rectangular frame structure with three steel sections forming a U-shaped inner groove. The main structural dimension of the U-shaped frame is larger than that of the mast column and is at least 1 meter larger.

4. The method for assembling and hoisting a modular foremast on a ship according to claim 3, characterized in that, The three steel sections are the side steel sections and the bottom steel section. The side steel sections are parallel and vertically fixed to both ends of the bottom steel section. Short steel sections are also vertically fixed to the ends of the side steel sections. The gap between the short steel sections is a reserved U-shaped inner groove opening as the opening of the U-shaped frame.

5. A method for assembling and hoisting a modular foremast on a ship according to claim 4, characterized in that, An elbow plate is provided at the angle between the short plate steel and the two side steel sections, and a diagonal bracing is provided at the angle between the two side steel sections and the bottom steel section.

6. A method for assembling and hoisting a modular foremast on a ship according to claim 5, characterized in that, Lifting lugs are fixed to both ends and the upper and lower surfaces of the two side steel sections. Four lifting lugs are provided on the upper and lower surfaces of the U-shaped frame. The arc of the line connecting the lifting points formed by the four lifting lugs is set with the same center as the arc of the line connecting the four lifting lugs on the top surface of the truncated cone of the base. The direction of the main lifting lug is consistent with the direction of the corresponding main lifting lug on the base platform.

7. A method for assembling and hoisting a modular foremast on a ship according to claim 4, characterized in that, A circular hole is provided on the outer end face of the short plate steel near the opening. The circular tube connecting rod is a circular tube with sealing plates on both sides. Lifting lugs are provided on the sealing plates at both ends, and the main plate direction of the lifting lugs at both ends is consistent.

8. A method for assembling and hoisting a modular foremast on a ship according to claim 4, characterized in that, The vertical projection dimension of the circular tube connecting rod is greater than the height of the center of gravity from the lug on the base, and is greater than 1 meter.

9. A method for assembling and hoisting a modular foremast on a ship according to claim 4, characterized in that, The spacing between the lifting lugs below the gantry is greater than the size of the mast's projected surface, and a safety margin of at least 1m is reserved around the edge of the mast's projected surface and the inner wall of the U-shaped frame.

10. A method for assembling and hoisting a modular foremast on a ship according to claim 7, characterized in that, In the tenth step, the main body of the sealing crossbar is a round tube, with sealing plates at both ends of the round tube, and square plates installed on the sealing plates. Round holes are opened on the square plates, and the size of the round holes is the same as the size of the round holes on the short plate steel, and the distance between the centers of the round holes is equal. The sealing crossbar is connected and fixed to the U-shaped frame by bolts and nuts.

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