Large ship tail casting installation method
By adopting a combined insertion and closing method, installing and inserting tail casting in segments, the problems of disruption in production plans and prolonging docking cycles caused by lag in tail casting are solved, and the accuracy control of the rear section axis and ships are realized on schedule.
Patent Information
- Application Number
- CN202510173238.2
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-02-17
- Publication Date
- 2025-03-18
AI Technical Summary
The lag in the stern casting and installation of large ships has caused production plans to be disrupted and the dock cycle has been extended, affecting the shipyard's reputation and production efficiency.
The combination insertion and closing method is adopted to divide the tail cast segments into installation sections and insertion sections. Through the cooperation of the AGV flatbed car and the total station, the tail cast insertion and closing is achieved to ensure the accuracy and consistency of the axis of the tail section.
It effectively avoids the extension of production cycle caused by tail casting lag, ensures ships are discharged on schedule, and improves the production efficiency and reputation of the shipyard.
Smart Images
Figure CN119637030A_ABST
Abstract
Description
Technical Field
[0001] The invention belongs to the field of installation technology of ship equipment, and in particular relates to a tail casting installation method for a large ship. Background Art
[0002] In order to improve the loading rate and speed, large ro-ro ships have a large tail line outward drift combined with the stern hull structure, and are equipped with a long shaft system with double shafts and double propellers. In order to improve the propulsion efficiency of the propeller, the shaft propeller adopts a tail-tilted type, so the tail shaft is about 40,000 mm long and extends out of the hull outer plate. Outside the tail shaft, there is a tail casting wrapped with a length of about 10,000 mm and a relatively thick thickness (the thickest part reaches 200 mm). In order to ensure the installation accuracy of the tail casting, the tail casting is generally installed in sections. Since the production time of the tail casting is relatively long, in order to prevent the tail casting from not arriving at the factory in time and affecting the production plan of the shipyard, the shipyard breaks the original production model and adopts a combined insertion and closing method to change the new construction and closing method, thereby ensuring a continuous production plan.
[0003] If the traditional construction method is adopted, the production department will wait for the tail casting (steel casting) equipment to arrive at the factory before continuing the installation in sections, which will disrupt the production plan. In serious cases, the docking schedule will also have to be adjusted accordingly. The direct consequence will be that the ship cannot be docked on schedule, increasing the risk of delay in delivery and affecting the reputation of the shipyard. Summary of the invention
[0004] In view of the above technical problems, the present invention provides a large ship tail casting installation method, which ensures the implementation of the ship production plan and does not extend the dock period due to tail casting delays.
[0005] To achieve the above object, the present invention adopts the following technical solution: A large tail casting installation method for a ro-ro ship, wherein the tail casting is composed of a tail casting segment AG01, a tail casting segment AG11, a tail casting segment AG02, a tail casting segment HS31, a cabin segment EB01, a cabin segment ED11, a cabin segment ED21 and a cabin segment HS32, and the tail casting segment AG02 is composed of an AG02 installation segment and an AG02 insertion segment. The tail casting installation method comprises the following steps: S1. Install the nacelle segment EB01, nacelle segment ED11, nacelle segment ED21, tail casting segment AG02, nacelle segment HS32, tail casting segment HS31, tail casting segment AG01, and tail casting segment AG11 in sequence; S2. After the construction of the AG02 installation section is completed, the AG02 shaft will enter the sand room for painting, and then it will be welded and installed with the engine room section EB01, engine room section ED11 and engine room section ED21, and then participate in the dock assembly; S3. After the construction of the AG02 insertion section is completed, mark the outer plates and the interior of the AG02 insertion section on both sides, hoist the AGV flatbed truck into the dock, and hoist the AG02 insertion section onto the AGV flatbed truck; S4. Set up the fore and aft target workbench and the total station fixing frame for lighting on the stern of the dock gate, and make the fore and aft bullseye reference points. The fore and aft target workbench should be placed at intervals from the hull; S5. Use the camera visual navigation collector on the AGV flatbed to use the camera of the AGV flatbed to "observe" the moving environment in a three-dimensional way. Combined with the guide mark target in the dock, analyze the image seen from the camera to track the position of the equipment, adjust the driving speed and the tail closure position on the AGV flatbed accordingly, move to the tail area of the AG02 installation section along the guide mark in the dock, and use the total station to illuminate from the stern to the bow based on the head and tail bull's eye reference points made in S4, and adjust the position of each auxiliary light target bull's eye to make it concentric with the initial tail segment axis; S6. Measure the axis data of the tail section before the AGV flatbed is moved to the installation position. According to the measured axis data of the tail section, move the AGV flatbed horizontally to the installation position of the AG02 insertion section. Combine the axis data to make fine adjustments up and down, and cooperate with the total station personnel to perform precise positioning, so that the center of the tail casting hole of the AG02 insertion section coincides with the center of the head and tail target stand worktables; S7. According to the positioning data on the AGV flatbed vehicle, combined with the coincidence data of the tail casting hole center of the AG02 insertion segment and the center of the first and tail target frame worktables, the AG02 insertion segment is inserted and positioned; S8. Use the total station to measure the tail segment axis at multiple points. If the center point of the tail casting hole of the AG02 insertion segment coincides with the initially determined tail segment axis, the closing of the AG02 insertion segment is completed. If the center point of the tail casting hole of the AG02 insertion segment does not coincide with the tail segment axis, according to the measured deviation value, install automatic compensation hoists on both sides of the inside of the tail casting segment AG02 large section, adjust the height of the AGV flatbed, adjust the AG02 insertion segment in place with the automatic compensation hoist, and remove the AGV flatbed. S9. Install a light target adjuster before and after the tail tube bearing position of the AG02 insertion section; S10. According to the laser point emitted from the tail target stand, pass through the target stand hole on the AG02 installation section, extend to the target stand of the cabin section EB01 through the AG02 insertion section optical target adjuster, and re-measure the entire tail section axis. According to the value of the optical target adjuster of the AG02 insertion section, use the automatic compensation hoists added on both sides of the tail casting section AG02 large section to adjust the AG02 insertion section. If the center point from the tail target stand to the EB01 segment target stand is ≥1mm away from the initially determined tail section axis, the AG02 insertion section is adjusted in place and the corresponding closing is completed; S11. According to the positioning of the AG02 insertion section, it is fixed with a card code and welded to form the whole ship.
[0006] Furthermore, in the S3, the horizontal marks of the punched holes on the outer plates on both sides and the interior of the AG02 insertion section are specifically as follows: first, the punched hole marks are made on the outer plates on both sides of the AG02 insertion section, and a rear laser level is installed, and the laser level is used to project the marks onto the target stand on the stern shaft hole. Punches are made on the strong T-profile panel of the internal structure of the AG02 insertion section, and a laser level is installed, and the marks are projected onto the target stand on the stern shaft hole to check whether the laser points at the inside and outside coincide with the points on the target stand on the stern shaft hole. If they coincide, the punched hole marks made inside and outside are on the same horizontal plane.
[0007] Furthermore, S3 also includes establishing the theoretical center line of the axis system with the laser of the total station, specifically: setting up a tripod, placing the total station on the tripod and tightening it; adjusting the foot screws of the total station to level the total station, preliminarily determining the left and right positions of the total station, adjusting until the total station light spot falls on the baseline, scanning the center line of the ship, so that the light spot of the total station laser falls on the center line measurement points 1 and 2 of the ship, and adjusting the left and right positions of the cross center of the tail reference target so that the cross center line of the target coincides with the light spot. At this time, the cross center of the target is the tail reference position, and adjusting the height of the total station so that the laser passes through the cross center of the reference point, thereby forming the line through which the laser of the total station passes to form the theoretical center line of the axis system.
[0008] Further, in S4, the head and tail target stands and target cores are set on the reference points of the head and tail target stand workbenches, and after the target core is loaded into the optical target body, it is installed on the optical target adjustment stand, and the position of the target core is adjusted by adjusting the fine-tuning screws of the optical target adjustment stand, and the two center points of the reference points of the head and tail target centers are determined.
[0009] Furthermore, the initially determined stern section axis is the stern section axis value determined when the axial holes and related shaft sections involved in the stern section axis related sections of the roll-on / roll-off ship are closed in the early stage, and the stern section axis value is the value from the hull line baseline and the half-width of the ship.
[0010] Furthermore, there are 6 auxiliary light targets, which are used to measure the axis of the tail section and the accuracy of the axis of the tail section when the hull is closed; among them, the first one is at the EB01 segment position, the second and third ones are respectively before and after the AG02 installation segment, the fourth and fifth ones are respectively before and after the AG02 insertion segment, and the sixth one is at the FR0 position.
[0011] Furthermore, the method for re-measurement of the axis of the tail segment is to first move the AG02 insertion segment to the bottom of the AG02 installation segment using the camera visual navigation and automatic guidance device on the equipment of the AGV flatbed vehicle, use the AGV flatbed vehicle to adjust and perform rough positioning, and then use the total station laser to pass through the light target adjuster on the axial hole of the AG02 insertion segment to the EB01 light target in combination with the midpoint of the "cross" on the front and rear end surfaces of the tail casting on the AG02 installation segment. According to the number projected by the laser to the light target adjuster, if the adjuster number is ≤1, it means that the center point of the casting hole of the AG02 installation segment coincides with the axis of the tail segment. If it is ≥1, it is necessary to use an automatic compensation hoist to adjust the AG02 installation segment left and right.
[0012] Further, in S9, specifically, firstly, a cross line is drawn on the end face of the tail pipe using a level ruler, and a measuring position mark is drawn using a protractor. Then, a light target is installed at each of the front and rear bearing positions of the tail tube, and the end face of the target core is roughly flush with the end face of the tail tube. The protractor is used to check the verticality of the target core and the axis of the tail section of the tail tube. The screw is adjusted, and the light target is adjusted in combination with the measurement data of the vernier caliper to make it coaxial with the tail tube bearing position hole.
[0013] The large ro-ro ship stern casting installation method of the present invention divides the entire stern casting segment AG02 into the stern casting segment AG02 insertion segment and the stern casting segment AG02 installation segment. The stern casting segment AG02 installation segment is constructed, painted, and closed according to the normal process flow. After the stern casting segment AG02 insertion segment is painted at the factory, the closure workshop will hoist the stern casting segment AG02 insertion segment into the dock, and use the camera visual navigation on the equipment of the AGV flatbed vehicle to automatically guide the device to move it to the closure site at the tail of the AG02 installation segment. The insertion method is used for closing, thereby ensuring the implementation of the ship production plan, and there is no extension of the docking cycle due to the lag of the stern casting; the stern casting segment AG02 insertion segment is automatically guided by the AGV flatbed vehicle. The laser insertion closing method solves the problem of the precision control of the closure tail segment axis, meets the standard range of the center line of the shaft rudder system and the lighting wire, and the data meets the requirements of the tail segment axis.
[0014] The large-scale ro-ro ship stern casting installation method of the present invention solves the technical problems that the tail casting cannot be installed in sections due to the lag of the tail casting, the sections cannot form a whole section, the production cycle is extended, and the subsequent dock closing is affected. It realizes the unfavorable factors of the lag of the tail casting (casting) of the ro-ro ship, verifies the feasibility of the insertion closing method of the engine room shaft system section, avoids the extension of the production cycle caused by the lag of the casting, and ensures the closing plan of subsequent ships in the dock; at the same time, it provides an effective basis for the diversified production organization mode of the shipyard in the future, and shortens the closing dock period, improves the installation environment, and obtains valuable closing experience through changes in the construction and closing methods. BRIEF DESCRIPTION OF THE DRAWINGS
[0015] Figure 1It is a schematic diagram of closing the insertion section of the tail casting segment AG02 in the large ship tail casting installation method described in the present invention.
[0016] Figure 2 This is a schematic diagram of the transfer of the tail casting segment AG02 insertion segment in the large ship tail casting installation method described in the present invention.
[0017] Figure 3 It is a schematic diagram of the segments of the tail casting segment AG02 described in the present invention.
[0018] Among them, 1-guidance marking target in the dock, 2-AGV flatbed vehicle, 3-camera visual navigation collector, 4-AG02P insertion segment, 5-AG02P insertion segment centerline, 6-tail segment axis, 7-signal transmitter, 8-dock, 9-AG02P installation segment. DETAILED DESCRIPTION
[0019] The present invention will be further described in detail below in conjunction with the accompanying drawings and specific embodiments. These embodiments are only used to illustrate the present invention and are not intended to limit the present invention.
[0020] In the description of the present invention, it should be noted that the terms "center", "longitudinal", "lateral", "upper", "lower", "front", "back", "left", "right", "vertical", "horizontal" and the like indicating directions or positional relationships are based on the directions or positional relationships shown in the accompanying drawings, and are only for the purpose of describing the present invention and simplifying the description, rather than indicating or implying that the positions or elements referred to must have a characteristic direction, be constructed and operated in a specific direction, and therefore cannot be understood as limiting the present invention. In addition, the terms "first" and "second" are used for descriptive purposes only, and cannot be understood as indicating or implying relative importance.
[0021] like Figure 1~Figure 3 As shown, a large tail casting installation method for a ro-ro ship is provided, wherein the tail casting is composed of a tail casting segment AG01, a tail casting segment AG11, a tail casting segment AG02, a tail casting segment HS31, a cabin segment EB01, a cabin segment ED11, a cabin segment ED21 and a cabin segment HS32, and the tail casting segment AG02 is composed of an AG02 installation segment and an AG02 insertion segment. The tail casting installation method comprises the following steps: S1. Install the nacelle segment EB01, nacelle segment ED11, nacelle segment ED21, tail casting segment AG02, nacelle segment HS32, tail casting segment HS31, tail casting segment AG01, and tail casting segment AG11 in sequence; S2. After the construction of the AG02 installation section is completed, the AG02 shaft will enter the sand room for painting, and then it will be welded and installed with the engine room section EB01, engine room section ED11 and engine room section ED21, and then participate in the dock assembly; S3. First, use the laser of the total station to establish the theoretical center line of the axis system, specifically: set up a tripod, place the total station on the tripod and tighten it; adjust the foot screws of the total station to level the total station, preliminarily determine the left and right positions of the total station, adjust until the total station light spot falls on the baseline, scan the center line of the ship, make the light spot of the total station laser fall on the measurement points 1 and 2 of the center line of the ship, and adjust the left and right positions of the cross center of the tail reference target to make the cross center line of the target coincide with the light spot. At this time, the cross center of the target is the tail reference position. Adjust the height of the total station so that the laser passes through the cross center of the reference point, thereby forming the line through which the laser of the total station passes to form the theoretical center line of the axis system.
[0022] Secondly, after the construction of the AG02 insertion section is completed, the outer plates and the interior of the AG02 insertion section are marked, specifically: the outer plates on both sides of the AG02 insertion section are marked with punch holes, and a rear laser level is installed, and the laser level is used to project the punch holes onto the target frame on the stern shaft hole. Punch holes are made on the strong T-profile panel of the internal structure of the AG02 insertion section, and a laser level is installed, and the punch holes are projected onto the target frame on the stern shaft hole to check whether the laser points at the inside and outside coincide with the points on the target frame on the stern shaft hole. If they coincide, the punch hole marks made inside and outside are on the same horizontal plane, and then the AGV flatbed truck is hoisted into the dock 8, and the AG02 insertion section is hoisted onto the AGV flatbed truck; S4. Set up the fore and aft target workbench and the total station fixing frame for lighting on the stern of the dock gate, and make the fore and aft bullseye reference points. The fore and aft target workbench should be placed at intervals from the hull; S5. Use the camera vision navigation collector 3 on the AGV flatbed vehicle 2 to "observe" the moving environment in a three-dimensional manner, combine with the guide mark target 1 in the dock, analyze the image seen from the camera vision navigation collector 3 to track the position of the equipment, adjust the driving speed and the tail closure position on the AGV flatbed vehicle 2 accordingly, move to the tail area of the AG02 installation section along the guide mark in the dock, and use the total station to illuminate from the stern to the bow based on the head and tail bull's eye reference points made in S4, adjust the position of each auxiliary light target bull's eye, and combine the signal transmitter 7 at the stern and the camera vision navigation collector 3 to make it concentric with the initial tail segment axis 6; S6. Before the AGV flatbed car 2 is moved to the installation position, the tail segment axis 6 data is measured. According to the measured tail segment axis 6 data, the AGV flatbed car 2 is moved horizontally to the installation position of the AG02 insertion segment. Combine the axis data to make fine adjustments up and down, and cooperate with the total station personnel to perform precise positioning, so that the center of the tail casting hole of the AG02 insertion section coincides with the center of the head and tail target stand worktables; S7. According to the positioning data on the AGV flatbed car 2, combined with the data of the coincidence of the center of the tail casting hole of the AG02 insertion segment and the center of the first and last target frame workbench, the AG02 insertion segment is inserted and positioned; S8. Use the total station to perform multi-point measurement on the tail segment axis 6. If the center point of the tail casting hole of the AG02 insertion segment coincides with the initially determined tail segment axis 6, the closing of the AG02 insertion segment is completed; if the center point of the tail casting hole of the AG02 insertion segment does not coincide with the tail segment axis 6, according to the measured deviation value, install automatic compensation hoists on both sides of the inside of the tail casting segment AG02 large section, adjust the height of the AGV flatbed 2, adjust the AG02 insertion segment in combination with the automatic compensation hoist in place, and remove the AGV flatbed 2; S9. Install a light target adjuster before and after the tail tube bearing position of the AG02 insertion section; S10. According to the laser point emitted from the tail target stand, pass through the target stand hole on the AG02 installation section, extend to the target stand of the cabin section EB01 through the AG02 insertion section optical target adjuster, and re-measure the entire tail section axis 6. According to the value of the optical target adjuster of the AG02 insertion section, use the automatic compensation hoists added on both sides of the tail casting section AG02 large section to adjust the AG02 insertion section. If the center point from the tail target stand to the EB01 segment target stand is ≥1mm from the initially determined tail section axis 6, the adjustment of the AG02 insertion section is in place, and the corresponding closing is completed; S11. According to the positioning of the AG02 insertion section, it is fixed with a card code and welded to form the whole ship.
[0023] In S4, the head and tail target stands and target core are set on the reference points of the head and tail target stand worktables, the target core is loaded into the optical target body, and then installed on the optical target adjustment stand, and the position of the target core is adjusted by adjusting the fine-tuning screws of the optical target adjustment stand, and the two center points of the reference points of the head and tail target centers are determined.
[0024] Furthermore, the initially determined stern section axis 6 is the value of the stern section axis 6 determined when the axial holes and related shaft sections of the stern section axis 6 related sections are closed in the early stage of the roll-on / roll-off ship. The value of the stern section axis 6 is the value from the hull line baseline and from the half-width of the ship.
[0025] There are 6 auxiliary light targets, the first one is at the EB01 segment position, the second and third ones are respectively before and after the AG02 installation segment, the fourth and fifth ones are respectively before and after the AG02 insertion segment, and the sixth one is at the FR0 position. These 6 auxiliary light targets are mainly used to measure the tail segment axis 6, and are used to measure and monitor the accuracy of the tail segment axis 6 when the hull is closed.
[0026] In S9, specifically, firstly, a cross line is drawn on the end face of the tail tube using a level ruler, and a measuring position mark is drawn using a protractor. Then, a light target is installed at each of the front and rear bearing positions of the tail tube. The end face of the target core is roughly flush with the end face of the tail tube. The verticality of the target core and the axis line 6 of the tail section of the tail tube is checked with a protractor. The screw is adjusted, and the light target is adjusted in combination with the measurement data of the vernier caliper to make it coaxial with the tail tube bearing position hole.
[0027] The method for re-measurement of the tail segment axis 6 is as follows: first, the AG02 insertion segment is moved to the bottom of the AG02 installation segment by using the camera vision navigation collector 3 and the automatic guidance device on the AGV flatbed vehicle 2, and adjusted by the AGV flatbed vehicle 2 for rough positioning. Then, combined with the midpoint of the "cross" on the front and rear end surfaces of the tail casting on the AG02 installation segment, the total station laser is used to pass through the light target adjuster on the axial hole of the AG02 insertion segment to the EB01 light target. According to the number projected by the laser to the light target adjuster, if the adjuster number is ≤1, it means that the center point of the casting hole of the AG02 installation segment coincides with the tail segment axis 6. If it is ≥1, the AG02 installation segment needs to be adjusted left and right with an automatic compensation hoist.
[0028] Those skilled in the art should understand that the above description is only a specific embodiment of the present invention and is 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 in the protection scope of the present invention.
Claims
1. A large ship tail casting installation method, characterized in that: The tail casting is composed of tail casting segment AG01, tail casting segment AG11, tail casting segment AG02, tail casting segment HS31, cabin segment EB01, cabin segment ED11, cabin segment ED21 and cabin segment HS32. The tail casting segment AG02 is composed of AG02 installation segment and AG02 insertion segment. The tail casting installation method comprises the following steps: S1. Install the nacelle segment EB01, nacelle segment ED11, nacelle segment ED21, tail casting segment AG02, nacelle segment HS32, tail casting segment HS31, tail casting segment AG01, and tail casting segment AG11 in sequence; S2. After the construction of the AG02 installation section is completed, the AG02 shaft will enter the sand room for painting, and then it will be welded and installed with the engine room section EB01, engine room section ED11 and engine room section ED21, and then participate in the dock assembly; S3. After the construction of the AG02 insertion section is completed, make horizontal marks on the outer plates and the inner part of the AG02 insertion section, hoist the AGV flatbed into the dock, hoist the AG02 insertion section onto the AGV flatbed, and then pass the AGV flatbed through the automatic guidance device; S4. Set up the fore and aft target workbench and the total station fixture for lighting on the stern of the dock gate, and make the fore and aft bullseye reference points. The fore and aft target workbench should be placed at intervals from the hull; S5. Use the camera visual navigation collector on the AGV flatbed vehicle, use the camera of the AGV flatbed vehicle to "observe" the moving environment in a three-dimensional way, combine the guide mark target in the dock, analyze the image seen from the camera to track the position of the equipment, and make corresponding adjustments to the driving speed and tail closure position on the AGV flatbed vehicle. Move to the tail area of the AG02 installation section along the guide mark in the dock. Based on the head and tail bull's eye reference points made in S4, use the total station to illuminate from the stern to the bow, and adjust the position of each auxiliary light target bull's eye to make it concentric with the initial tail segment axis; S6. Measure the axis data of the tail section before the AGV flatbed is moved to the installation position. According to the measured axis data of the tail section, move the AGV flatbed horizontally to the installation position of the AG02 insertion section. Combine the axis data to make fine adjustments up and down, and cooperate with the total station personnel to perform precise positioning, so that the center of the tail casting hole of the AG02 insertion section coincides with the center of the head and tail target stand worktables; S7. According to the positioning data on the AGV flatbed vehicle, combined with the coincidence data of the tail casting hole center of the AG02 insertion segment and the center of the first and tail target frame worktables, the AG02 insertion segment is inserted and positioned; S8. Use the total station to measure the tail segment axis at multiple points. If the center point of the tail casting hole of the AG02 insertion segment coincides with the initially determined tail segment axis, the closing of the AG02 insertion segment is completed. If the center point of the tail casting hole of the AG02 insertion segment does not coincide with the tail segment axis, according to the measured deviation value, install automatic compensation hoists on both sides of the inside of the tail casting segment AG02 large section, adjust the height of the AGV flatbed, adjust the AG02 insertion segment in place with the automatic compensation hoist, and remove the AGV flatbed. S9. Install a light target adjuster before and after the tail tube bearing position of the AG02 insertion section; S10. According to the laser point emitted from the tail target stand, pass through the target stand hole on the AG02 installation section, extend to the target stand of the cabin section EB01 through the AG02 insertion section optical target adjuster, and re-measure the entire tail section axis. According to the value of the optical target adjuster of the AG02 insertion section, use the automatic compensation hoists added on both sides of the tail casting section AG02 large section to adjust the AG02 insertion section. If the center point from the tail target stand to the EB01 segment target stand is ≥1mm away from the initially determined tail section axis, the AG02 insertion section is adjusted in place and the corresponding closing is completed; S11. According to the positioning of the AG02 insertion section, it is fixed with a card code and welded to form the whole ship.
2. A large ship tail casting installation method according to claim 1, characterized in that: In the S3, the horizontal marks of the punched holes on the outer plates on both sides and the interior of the AG02 insertion section are specifically as follows: first, the punched hole marks are made on the outer plates on both sides of the AG02 insertion section, and a rear laser level is installed, and the laser level is used to project the marks onto the target frame on the stern shaft hole. Punches are made on the strong T-profile panel of the internal structure of the AG02 insertion section, and a laser level is installed, and the marks are projected onto the target frame on the stern shaft hole to check whether the laser points at the inside and outside coincide with the points on the target frame on the stern shaft hole. If they coincide, the punched hole marks made inside and outside are on the same horizontal plane.
3. A large ship tail casting installation method according to claim 1, characterized in that: The S3 also includes establishing the theoretical center line of the axis system with the laser of the total station, specifically: setting up a tripod, placing the total station on the tripod and tightening it; adjusting the foot screws of the total station to level the total station, preliminarily determining the left and right positions of the total station, adjusting until the light spot of the total station falls on the baseline, scanning the center line of the ship, so that the light spot of the total station laser falls on the measurement points 1 and 2 of the center line of the ship, and adjusting the left and right positions of the cross center of the tail reference target so that the cross center line of the target coincides with the light spot. At this time, the cross center of the target is the tail reference position, and adjusting the height of the total station so that the laser passes through the cross center of the reference point, thereby forming the line through which the laser of the total station passes to form the theoretical center line of the axis system.
4. A large ship tail casting installation method according to claim 1, characterized in that: In S4, the head and tail target stands and target core are set on the reference points of the head and tail target stand worktables, the target core is loaded into the optical target body, and then installed on the optical target adjustment stand, and the position of the target core is adjusted by adjusting the fine-tuning screws of the optical target adjustment stand, and the two center points of the reference points of the head and tail target centers are determined.
5. A large ship tail casting installation method according to claim 1, characterized in that: In S5, the initially determined stern section axis is the stern section axis value determined when the axial holes and related shaft sections of the stern section axis related sections are closed in the early stage of the ro-ro ship. The stern section axis value is the value from the hull line baseline and the midship half width.
6. A large ship tail casting installation method according to claim 1, characterized in that: In S5, there are 6 auxiliary light targets, which are used to measure the axis of the tail section and the accuracy of the axis of the tail section when the hull is closed; among them, the first one is at the EB01 segment position, the second and third ones are respectively before and after the AG02 installation segment, the fourth and fifth ones are respectively before and after the AG02 insertion segment, and the sixth one is at the FR0 position.
7. A large ship tail casting installation method according to claim 1, characterized in that: In S10, the method for re-measurement of the axis of the tail segment is to first move the AG02 insertion segment to the bottom of the AG02 installation segment by using the camera visual navigation and automatic guidance device on the equipment of the AGV flatbed vehicle, and use the AGV flatbed vehicle to adjust and roughly position it. Then, combined with the midpoint of the "cross" on the front and rear end surfaces of the tail casting on the AG02 installation segment, use the total station laser to pass through the light target adjuster on the axial hole of the AG02 insertion segment to the EB01 light target, and according to the number projected by the laser to the light target adjuster, if the adjuster number is ≤1, it means that the center point of the casting hole of the AG02 installation segment coincides with the axis of the tail segment. If it is ≥1, it is necessary to use an automatic compensation hoist to adjust the AG02 installation segment left and right.
8. A large ship tail casting installation method according to claim 1, characterized in that: In S9, specifically, firstly, a cross line is drawn on the end face of the tail tube using a level ruler, and a measuring position mark is drawn using a protractor. Then, a light target is installed on each of the front and rear bearing positions of the tail tube, and the end face of the target core is flush with the end face of the tail tube. The verticality of the target and the axis of the tail section of the tail tube is checked with a protractor. The screw is adjusted, and the light target is adjusted in combination with the measurement data of the vernier caliper to make it coaxial with the tail tube bearing position hole.