A method for heightening a marine vessel helicopter platform

Abstract

The application relates to the technical field of ship modification processing, and discloses a method for heightening and modifying a marine ship aircraft platform, which comprises the following steps: simulating and determining a center point on AutoCAD according to the size coordinates of a prefabricated steel truss; determining the number, height and position of a jig frame according to the center point, and manufacturing the jig frame at a wharf; prefabricating a steel truss on the jig frame; removing the aircraft platform from the ship; hoisting and transporting the removed aircraft platform to the wharf to fold the steel truss to form a new aircraft platform; and hoisting and transporting the new aircraft platform to the ship to install the new aircraft platform. According to the method, the jig frame is arranged at the wharf, the steel truss is manufactured on the jig frame, the original aircraft platform is cut, the original aircraft platform is folded with the prefabricated steel truss at the wharf, and then the folded new aircraft platform is hoisted and transported to the ship to be assembled, the whole process does not need to turn over the steel truss, the deformation of the steel truss is avoided, the modification quality is greatly improved, and the modification period is shortened.

Description

Technical Field

[0001] This invention relates to the field of ship modification and processing technology, specifically to a method for raising and modifying an aircraft platform for offshore engineering vessels. Background Technology

[0002] The existing shipborne helicopter platform has overall dimensions of approximately 32m long × 25m wide × 20m high. The platform is made of aluminum alloy, and the supporting steel truss is made of carbon steel. The supporting steel truss is bolted to the aluminum alloy platform. With the continuous upgrading and transformation of marine engineering technology, in order to better adapt the helicopter platform to the working environment, it is usually necessary to modify the helicopter platform by increasing its height. In existing technology, the reverse construction method is usually used for modification. The reverse construction requires flipping the steel truss, which is a complex process. Moreover, the steel truss is made of aluminum alloy, which is prone to deformation during flipping. The subsequent correction work is also extensive, greatly extending the modification cycle. Summary of the Invention

[0003] The purpose of this invention is to provide a method for raising and modifying an aircraft platform for offshore engineering vessels. This method has a simple procedure and a short modification cycle.

[0004] To achieve the above objectives, the present invention provides a method for raising and modifying an aircraft platform on an offshore vessel, comprising:

[0005] The center point is determined by simulation in AutoCAD based on the dimensional coordinates of the prefabricated steel truss;

[0006] The number, height, and location of the jigs are determined based on the center point, and they are manufactured at the dock.

[0007] Prefabricate steel trusses on the fixture;

[0008] Remove the aircraft platform from the ship;

[0009] The dismantled aircraft platform was hoisted to the dock and joined with the steel truss to form a new aircraft platform;

[0010] The new aircraft platform was hoisted onto the ship for installation.

[0011] Preferably, the jig includes iron blocks and composite blocks, and determining the number, height, and position of the jig based on the center point includes:

[0012] Using the center point as a reference, draw the longitudinal / transverse center lines, left / right main support pipe center lines, and outer contour of the steel truss on the ground. Determine the number and location of the iron blocks based on the connection stress points of the steel truss. Based on the portion of the aircraft platform to be dismantled that extends beyond the steel truss, symmetrically set up combined blocks along the longitudinal center line. Calculate the height of the iron blocks and combined blocks based on the height dimensions of the steel truss.

[0013] Preferably, the manufacturing at the wharf comprises:

[0014] Padding steel plates at the determined installation position, and installing iron piers or combined piers on the steel plates, and installing a jig template on the iron piers or combined piers.

[0015] Preferably, the installing the jig template on the iron piers or combined piers comprises:

[0016] Firstly, a horizontal reference plane is punched by laser, and then the jig template height is positioned based on the horizontal reference plane.

[0017] Preferably, the jig template is a crescent-shaped jig template.

[0018] Preferably, the prefabricating the steel truss on the jig comprises:

[0019] The steel truss is prefabricated in sections, and the sections are fabricated on the jig template based on the left and right two main support pipes at the bottom.

[0020] Preferably, the removing the airplane platform from the ship comprises:

[0021] Measuring the positioning size of the airplane platform closing opening on the ship;

[0022] Hanging a frame on the four corners of the airplane platform, disassembling part of the pipeline and safety net, extending the original I-beam, and welding lifting lugs on the extended I-beam;

[0023] Installing temporary diagonal bracing pipes and steel wires on the support legs of the airplane platform;

[0024] Removing or disconnecting the fire-fighting pipes, cables, inclined ladders and walkway platforms at the cutout;

[0025] Hanging a frame on the top of the support legs of the airplane platform, and after the floating crane hook is hung, the support pipe at the top end of the support legs is first cut, and then the support pipe connected with the compass deck is cut.

[0026] Preferably, the hoisting the removed airplane platform to the wharf to close with the steel truss comprises:

[0027] The airplane platform is placed flat on the steel truss section by the floating crane to close and position;

[0028] After closing, precision detection, weld appearance inspection and flaw detection are performed.

[0029] Preferably, the hoisting the new airplane platform to the ship for installation comprises:

[0030] Removing the old structure in the compass deck thickened plate area and the interior of the driver room on the ship.

[0031] A guiding tool is installed at the inclined strutting pipe folding opening;

[0032] The new aircraft platform is hoisted from the wharf to the ship by a floating crane for installation.

[0033] Preferably, the guiding tool comprises guiding semicircular plates arranged outside the inclined strutting pipe folding opening at the bow of the new aircraft platform and guiding fenders arranged at the inclined strutting pipe folding opening of the support legs.

[0034] Compared with the prior art, the present application has the following beneficial effects:

[0035] The present application sets a jig on the wharf, constructs a steel truss on the jig, cuts the original aircraft platform, folds the original aircraft platform with the prefabricated steel truss on the wharf, and then hoists the folded new aircraft platform to the ship for assembly, so that the steel truss is not turned over in the whole process, the deformation of the steel truss is avoided, the modification quality is greatly improved, the construction period is shortened by at least two days, and strong technical support is provided for modification of the same type of ship, and the competitiveness of the company in undertaking similar projects in the future is improved.

[0036] Other features and advantages of the present application will be described in detail in the following specific embodiments. BRIEF DESCRIPTION OF DRAWINGS

[0037] The accompanying drawings are included to provide a further understanding of the present application, and constitute a part of the specification, and are used together with the following specific embodiments to explain the present application, but do not constitute a limitation on the present application. In the drawings:

[0038] Figure 1 A flow chart of the method for heightening and modifying the aircraft platform of the offshore ship according to the present application is shown;

[0039] Figure 2 A structural schematic view of the steel truss according to an embodiment of the present application is shown;

[0040] Figure 3 A distribution schematic view of the folding jig according to an embodiment of the present application is shown;

[0041] Figure 4 A lateral view of the folding jig according to an embodiment of the present application is shown;

[0042] Figure 5 A transverse schematic view of the folding jig according to an embodiment of the present application is shown;

[0043] Figure 6 A structural schematic view of the iron pier according to an embodiment of the present application is shown;

[0044] Figure 7An old aircraft platform measurement marking drawing of an embodiment of the present application is shown.

[0045] Figure 8 An aircraft platform pre-processing top view of an embodiment of the present application is shown. Figure 6 A middle G-G plane schematic view is shown.

[0046] Figure 9 An aircraft platform pre-processing top view of an embodiment of the present application is shown.

[0047] Figure 10 An aircraft platform pre-processing side view of an embodiment of the present application is shown.

[0048] Figure 11 A temporary diagonal brace tube installation schematic view of an embodiment of the present application is shown.

[0049] Figure 12 A steel wire rope installation schematic view of an embodiment of the present application is shown.

[0050] Figure 13 An aircraft platform on-ship disassembly schematic view of an embodiment of the present application is shown.

[0051] Figure 14 An aircraft platform wharf closing schematic view of an embodiment of the present application is shown.

[0052] Figure 15 A steel truss closing temporary reinforcement installation schematic view of an embodiment of the present application is shown.

[0053] Figure 16 A guide tool installation position view of an embodiment of the present application is shown.

[0054] Figure 17 A guide tool structure schematic view of an embodiment of the present application is shown.

[0055] Figure 18 An aircraft platform hoisting on-ship process view of an embodiment of the present application is shown. DETAILED DESCRIPTION

[0056] The specific embodiments of the present application are described in detail below with reference to the accompanying drawings. It should be understood that the specific embodiments described herein are merely intended for illustration and explanation of the present application and are not intended to limit the present application.

[0057] In the present embodiment, due to the upgrade of the main crane, the aircraft platform needs to be increased by 3m (i.e. adding a 3m high steel truss and ladder walkway at the top of the support leg).

[0058] The present embodiment discloses a method for increasing the height of a marine vessel aircraft platform, which specifically comprises the following steps. As shown in Figure 1 the present embodiment.

[0059] Step S1: Before the aircraft platform is removed from the ship, a cradle is erected on the wharf, and a 3m steel truss segment is prefabricated on the cradle;

[0060] Step S2: Before the ship is docked, the aircraft platform is removed from the ship using a floating crane, and the aircraft platform is hoisted to the wharf and laid flat on the 3m steel truss segment for overall folding;

[0061] Step S3: After the aircraft platform is modified, the helicopter platform is hoisted from the wharf to the ship using a floating crane for installation, and the newly added ladder walkway and other accessories are installed, and the fire pipe, cable, etc. are restored.

[0062] The above method is described in detail below.

[0063] 1. Design of the cradle

[0064] 1.1 Determine the cradle:

[0065] Before construction, CAD drawings of the steel truss are designed according to the size, and then the horizontal center line and the vertical center line of the steel truss segment are simulated on AutoCAD, and then the center point, i.e. the intersection of the horizontal center line and the vertical center line, is determined. In this embodiment, there is a size difference between the aircraft platform to be removed and the steel truss, and the aircraft platform to be removed will exceed the steel truss in the left and right directions and the rear end, as shown in Figure 2 and Figure 3 Therefore, the cradle is based on the combined pier and the iron pier, and the number, position and height of the iron pier and the combined pier need to be designed respectively.

[0066] 1.1.1 Design of the iron pier: The longitudinal / horizontal center line, the left / right main support pipe center line and the outline of the steel truss are drawn on the ground based on the center point, the number and position of the iron pier are determined according to the connection stress points of the steel truss, i.e. the iron pier mounting point is arranged at the intersection of the left / right support pipe and other steel pipes, and the height of the iron pier is calculated according to the height size of the steel truss.

[0067] 1.1.2 Design of the combined pier: Similar to the design of the iron pier, the difference is that the part of the aircraft platform to be removed that exceeds the steel truss is arranged symmetrically along the longitudinal center line, i.e. the outline of the aircraft platform to be removed is drawn based on the center point according to the size of the aircraft platform to be removed, and then the longitudinal center line is arranged symmetrically around the outline, the number is arranged according to the stress point, and the height is about 3m higher than the height of the iron pier, i.e. the height of one steel truss exceeds the height of the iron pier (as shown in Figures 3-5 ).

[0068] As shown in Figure 3As shown, in the present embodiment, there are designed 10 25T iron piers, with a height of 1000mm, and 8 combined piers, with a height of 4050mm.

[0069] 1.2 Installation of the tire frame

[0070] The iron piers and the combined piers have basically the same structure, except that the heights are different. The installation method is as follows: a steel plate is laid at a determined installation position, then an iron pier or a combined pier is installed on the steel plate, and a tire frame template is installed on the iron pier or the combined pier. The tire frame template is crescent-shaped, i.e. the top is arc-shaped, as shown in Figure 6 Due to the circular shape of the support pipe, the tire frame and the support pipe can be more closely matched, and the difficulty of the modification is reduced.

[0071] Before the installation of the tire frame template, a horizontal reference surface is first punched by laser, and then the height positioning of the tire frame template is performed based on the horizontal reference surface. When the tire frame template is installed, the center distance between the left and right main support pipes and the horizontal center lines of the left and right main support pipes need to be ensured to be on the same horizontal plane, and the deviation is not more than ±2mm.

[0072] 2. Prefabrication of the steel truss

[0073] The steel truss is prefabricated in sections, with the left and right two main support pipes at the bottom as the reference, and the erection is performed on the tire frame template according to the CAD drawing. During the erection, the horizontal included angle of the connecting line of the left and right main support pipes and the connecting end of the compass deck on the ship needs to be consistent with the horizontal included angle of the connecting surface of the compass deck on the ship, i.e. the left and right two main support pipes are long and short. Please refer to Figure 2 In the present embodiment, the horizontal included angle of the connecting line is 65°, and the left main support pipe is relatively short.

[0074] The compass deck thickening plate is prefabricated at the connecting position of the steel truss and the compass deck, so that the connection is more stable during the subsequent connection with the compass deck. Specifically, the compass deck thickening plate is prefabricated at the connecting end of the left main support pipe and the compass deck, and the compass deck thickening plate on the right main support pipe is bulk-loaded on the ship. The fillet weld of the right main support pipe and the compass deck thickening plate is welded after the adjustment of the gap positioning on site after the airplane platform is reloaded. It needs to be noted that temporary reinforcement needs to be provided at the right angle connecting position at the bottom of the steel truss to prevent deformation of the support, and the temporary reinforcement is reinforced by angle steel.

[0075] 3. Removal of the airplane platform

[0076] The airplane platform in the present embodiment is a helicopter platform.

[0077] 3.1 Data measurement

[0078] Before the helicopter platform is dismantled, the total station is used to detect the positioning size of the closing opening of the original ship old structure, which is used as the reference basis for the prefabrication of the steel truss section and the closing positioning of the steel truss section and the support leg and the compass deck. The specific measurement position is shown in Figure 7 and Figure 8 . Among them, L1 represents the distance from the center point of the left side main support pipe to the compass deck, L2 represents the vertical distance from the center point of the right side main support pipe to the connection point of the left side main support pipe and the compass deck, L3 and L4 respectively represent the distance from the center point of the left and right side main support pipes to the right end point of the support leg, H1 and H2 respectively represent the height between the connection of the left and right side main support pipes and the compass deck and the A deck, H3 and H4 respectively represent the height between the center point of the left and right side main support pipes and the A deck, H5 and H6 respectively represent the height between the connection of the left and right side main support pipes and the right end of the support leg and the A deck, B1 and B2 respectively represent the distance between the connection of the left and right side main support pipes and the compass deck, B3 and B4 respectively represent the distance between the center points of the left and right side main support pipes, and B5 and B6 respectively represent the distance between the connection of the left and right side main support pipes and the right end of the support leg. The measured distance is compared with the size coordinates of the steel truss to check whether adjustment is needed.

[0079] 3.2 Helicopter platform pre-processing

[0080] First, the inverted hanger is set up at the four corners of the helicopter platform, then part of the pipeline and safety net are disassembled, then the original I-beam is extended, and the lifting lug is welded on the extended I-beam. After the installation and welding of the I-beam and the lifting lug are completed, the appearance inspection and flaw detection of the weld are required; the I-beam and the lifting lug are qualified for use. As shown in Figure 9 and Figure 10 .

[0081] 3.3 Installation of temporary diagonal bracing pipe and steel wire rope

[0082] After the helicopter platform is dismantled, the support leg loses the connection with the compass deck, and the temporary diagonal bracing pipe and the steel wire rope are set to prevent the support leg from collapsing. The temporary diagonal bracing pipe is formed by splicing multiple round pipes.

[0083] 3.3.1 Installation of temporary diagonal bracing pipe

[0084] First, the column of the support leg is connected with the A deck through a long round pipe (Φ219x10), and then a plurality of short round pipes (Φ150x10) are used to connect the long round pipe with the column of the support leg, forming a temporary diagonal bracing pipe, as shown in Figure 11 .

[0085] 3.3.2 Installation of steel wire rope

[0086] First, prepare several 5T steel wire ropes, then install 5T flower at both ends of each steel wire rope, then install 5T shackle + 10T lifting lug connection group at the free end of the front wall of the living area and the column of the support leg, then form a steel wire rope support net through the flower and the lifting lug connection, as shown in Figure 12 The 5T shackle + 10T lifting lug connection group is provided with 5 in the vertical direction of the free end of the front wall of the living area, and 2 on the column of the support leg. The specific number is determined according to the height of the front wall of the living area and the height of the support leg.

[0087] In addition, temporary reinforcement is also needed, that is, angle steel is arranged at the cutout of the support leg for reinforcement, which is removed after the installation of the helicopter platform.

[0088] 3.4 Removal of the aircraft platform

[0089] Remove or disconnect the fire pipe, cable, inclined ladder and walkway platform at the cutout, and set up an inverted hook at the top end of the support leg of the helicopter platform. After the floating crane hook is hung, the support pipe is cut from the top end of the support leg, and then the support pipe is cut from the compass deck.

[0090] The steel wire rope of the floating crane adopts 4 45T steel wire ropes with a length of 50m. Each steel wire rope is connected with the hook through a 55T shackle, and the included angle between adjacent steel wire ropes is 46°. The parameters of the main and auxiliary hooks of the floating crane are shown in Tables 1 and 2, and the hoisting process of the floating crane is shown in Figure 13 .

[0091] Table 1 Main hook safety working load table

[0092] Boom elevation (°) 70 65 60 55 50 45 Workload (t) 2x300 2x275 2x225 2x150 2x100 2x50 Swath (m) 28.8 34.9 40.8 46.3 51.5 56.3 Lift height (m) 70.0 67.2 63.9 60.1 55.8 51.1

[0093] Table 2 Auxiliary hook safety working load table

[0094] Boom elevation (°) 70 65 60 55 50 45 Workload (t) 300 280 260 190 120 70 Swath (m) 42.1 50.7 58.9 66.7 74.0 80.7 Lift height (m) 100.0 95.9 91.2 85.7 79.5 72.8

[0095] 4 Hoisting the removed aircraft platform to the wharf and combining the prefabricated steel truss

[0096] The helicopter platform is transported to the wharf using the floating crane, and is placed on the steel truss section for modification and construction. During construction, angle steel needs to be installed at the joint to temporarily reinforce the section, and then the old pipe is removed and replaced on site (as shown in Figure 14 and Figure 15 ). After the helicopter platform is combined with the 3m steel truss section, precision measurement, weld appearance inspection and flaw detection are carried out.

[0097] 5 Hoisting the new aircraft platform to the ship for installation

[0098] Remove the old structure of the compass deck thick plate area and the interior of the bridge room, and the compass deck thick plate on the right side of the ship is replaced in advance. Note: Before the heat work of the compass deck thick plate, the glass and interior of the bridge room need to be temporarily removed locally, and various equipment, instruments, meters, cables, etc. in the bridge room need to be protected.

[0099] A guide tool is installed at the position of the folding opening of the diagonal brace tube at the bow of the helicopter platform, and the guide tool includes a guide semicircular plate arranged outside the folding opening of the diagonal brace tube at the bow of the helicopter platform and a guide code plate arranged at the folding opening of the diagonal brace tube of the support leg, and the two guide tools are matched with each other to provide a guide for the folding of the new helicopter platform (as shown in Figure 16 and Figure 17 ).

[0100] After the modification of the helicopter platform is completed, the helicopter platform is lifted from the head of the dock to the ship by using a floating crane for installation, and the lifting process is as shown in Figure 18 , and finally, the passageway platform, diagonal ladder and other fittings are installed, and the cables, pipelines and other accessories are restored.

[0101] Through the modification of the aircraft platform, a complete set of construction processes is formed, and each step is strictly performed according to the established process technical requirements: construction planning → steel truss prefabrication → helicopter platform removal → helicopter platform dock folding → helicopter platform lifting → completion. Through this complete set of modification technology, the modification quality is greatly improved, the period is shortened, and strong technical support is provided for the modification of the same type of ships. The competitiveness of the company is improved for undertaking similar projects in the future.

[0102] The preferred embodiments of the present application are described in detail above with reference to the drawings, but the present application is not limited to the specific details in the above-described embodiments, and various simple modifications can be made to the technical solutions of the present application within the technical concept of the present application, and these simple modifications all belong to the protection scope of the present application. In addition, it should be noted that each specific technical feature described in the above-described specific embodiments can be combined in any appropriate manner without contradiction, and in order to avoid unnecessary repetition, the present application will not further describe various possible combination manners.

[0103] In addition, various different embodiments of the present application can also be combined in any manner, as long as they do not deviate from the idea of the present application, and they should also be considered as disclosed by the present application.

Claims

1. A method for raising and modifying an aircraft platform on an offshore engineering vessel, characterized in that, include: The center point is determined by simulation based on the dimensional coordinates of the prefabricated steel truss; The number, height, and location of the jigs are determined based on the center point, and they are manufactured at the dock. Prefabricate steel trusses on the jig: construct steel trusses on the jig; Remove the aircraft platform from the ship; The dismantled aircraft platform was hoisted to the dock and joined with the steel truss to form a new aircraft platform; The new aircraft platform was hoisted onto the ship for installation. The removal of the aircraft platform from the ship includes: Measure the positioning dimensions of the aircraft platform closure opening on the ship; Inverted frames were erected at the four corners of the aircraft platform, some pipelines and safety nets were disassembled and installed, the original I-beams were extended, and lifting lugs were welded onto the extended I-beams; Temporary diagonal bracing pipes and steel wire ropes were installed on the support legs of the aircraft platform; Remove or disconnect fire pipes, cables, inclined ladders, and walkway platforms at the cut-off point; After installing an inverted frame on top of the aircraft platform support leg and hooking the floating crane, first cut the support pipe at the top of the support leg, and then cut the support pipe connected to the compass deck. The process of hoisting the dismantled aircraft platform to the dock and assembling it with the steel truss includes: The aircraft platform is placed flat onto the steel truss section using a floating crane for assembly and positioning. After the weld is assembled, precision testing, weld appearance inspection, and flaw detection are performed. The process of hoisting the new aircraft platform onto the ship for installation includes: Remove the old structure of the compass deck thickened plate area on the vessel and the interior of the wheelhouse; Install guide fixtures at the junction of the inclined bracing tubes; The new aircraft platform was lifted from the dock onto the vessel using a floating crane for installation. The process involves cutting the original aircraft platform and assembling it with a prefabricated steel truss at the dock, then hoisting the assembled new aircraft platform onto a ship for assembly. The entire process does not require turning the steel truss over.

2. The method for raising and modifying an offshore vessel aircraft platform according to claim 1, characterized in that, The jig includes iron blocks and composite blocks. Determining the number, height, and position of the jig based on the center point includes: Using the center point as a reference, draw the longitudinal / transverse center lines, left / right main support pipe center lines, and outer contour of the steel truss on the ground. Determine the number and location of the iron blocks based on the connection stress points of the steel truss. Based on the portion of the aircraft platform to be dismantled that extends beyond the steel truss, symmetrically set up combined blocks along the longitudinal center line. Calculate the height of the iron blocks and combined blocks based on the height dimensions of the steel truss.

3. The method for raising and modifying an offshore vessel aircraft platform according to claim 2, characterized in that, The manufacturing at the dock includes: Place a steel plate at the determined installation location, and install iron blocks or combined blocks on the steel plate. Then, install a formwork template on the iron blocks or combined blocks.

4. The method for raising and modifying an offshore vessel aircraft platform according to claim 3, characterized in that, The installation of the formwork template on the iron pier or composite pier includes: First, a horizontal reference surface is created using a laser, and then the height of the jig template is positioned using the horizontal reference surface as a reference.

5. The method for raising and modifying an offshore vessel aircraft platform according to claim 4, characterized in that, The template for the jig is a crescent-shaped jig template.

6. The method for raising and modifying an offshore vessel aircraft platform according to claim 4, characterized in that, The prefabricated steel truss on the jig includes: The steel truss is prefabricated in sections, with the sections based on the two main support pipes on the bottom left and right, and are constructed on the formwork template.

7. The method for raising and modifying an offshore vessel aircraft platform according to claim 1, characterized in that, The guiding fixture includes a guide semicircular plate located outside the closure opening of the inclined support tube at the front end of the new aircraft platform and a guide code plate located at the closure opening of the inclined support tube of the support leg.

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