Inclined slipway hull sinking jacking reset method

Abstract

According to the inclined slipway hull sinking jacking and resetting method, through the combined action of the jack and the steel support, jack jacking and steel support matched supporting, inclined slipway hull sinking jacking and resetting are achieved, it is guaranteed that the hull reaches the designated position, and it is guaranteed that the axis-rudder system stay wire position and the center line meet the design requirements through resetting adjustment; and the accuracy of ship deflection measurement data is ensured.

Description

Technical Field

[0001] The invention relates to a method for sinking, lifting and resetting a hull of an inclined berth, and belongs to the technical field of ships. Background Art

[0002] The installation and adjustment of the shaft and rudder system is a key link in the ship construction process. The correct installation of the shaft and rudder system is crucial to the navigation performance and safety of the ship. The wire pulling operation is an important task in the installation process of the shaft and rudder system. It involves the precise adjustment between the rudder blade and the rudder stock to ensure that the rudder blade can smoothly respond to the command of the steering gear to achieve the turning of the ship. If the hull sinks, the position of the shaft and rudder system may be offset, which in turn affects the normal operation of the wire pulling. In addition, the sinking of the hull may also affect the centerline alignment of the shaft and rudder system. If the centerline deviates, the wire pulling operation will not be able to proceed normally.

[0003] Hull deflection, that is, the deflection of the hull caused by the total longitudinal bending moment, shear force and temperature difference, is an important parameter in ship engineering. The sinking of the hull may affect the measurement of the above data.

[0004] Solutions to the above problems may include readjusting the shaft and rudder system to ensure that its position and centerline meet the design requirements, and may require lifting and resetting the sinking hull of the slipway. Summary of the invention

[0005] The object of the present invention is to provide a method for sinking and lifting and resetting the hull of an inclined slipway to solve the problems raised in the above-mentioned background technology.

[0006] The present invention provides the following technical solutions: A method for jacking and resetting a hull of an inclined slipway when it sinks, comprising a slipway, a hull, a jacking device and a tooling assembly, wherein the jacking device comprises a hydraulic pump station, a jack, a hydraulic pipeline, a central controller and a displacement sensor, wherein the jack is connected to the hydraulic station through an oil circuit for force transmission, and each hydraulic pump station is connected through an electrical signal line and controlled by the central controller to lift a target object, and at the same time, the central controller receives signal feedback from the displacement sensor to control the lifting height, and the tooling assembly comprises a plurality of temporary steel supports, a plurality of round tube support bases at the bottom of the jack, a plurality of semi-permanent steel pipe supports, and a plurality of The dock piers and supporting piers, cutting equipment and welding equipment that need to be replaced. The jacks are located under the six beams at the stern reaction force concentration point of the hull and under the hull near the middle and gradually distributed to both sides. The jacks are installed on the upper end surface of the circular tube support base, the temporary steel support is installed under the hull, and the semi-permanent steel pipe support is located under the hull and the beams. How to use: The first step is to prepare the jacking equipment and tooling components, and clean the installation position of the jack; the second step is to transport the prepared tooling components to the location first, and take the dock piers and related materials to the vicinity of the installation location; The third step is to check whether there are construction personnel on board, arrange to evacuate the construction personnel on board, and set up the warning area for on-site equipment, and prohibit irrelevant personnel from entering the jacking construction site; the fourth step is to remove the failed dock pier at the stern and reinforce the original position with a pier support; the fifth step is to install 18 temporary steel supports at the FR52-FR54 ribs on the bottom of the hull; the sixth step is to check the number of jacks to be installed. After testing, install the jacks on the round tube support base, and install the adjustment components according to the remaining space to ensure that the adjustment components fit the hull and will not fall off; the seventh step is to prepare for jacking after the jacks are installed, and check the Whether the equipment and tooling are in place and intact, the jacks have been pre-debugged and confirmed that all jacks are functioning normally before the jacking operation can be carried out. During jacking, always pay attention to the status of the jacks and record the various data of the jacks during jacking in real time; Step 8. While performing the jacking operation, the precision department shall monitor the accuracy status of the entire ship in real time. The jack shall stop jacking after reaching the jacking height according to the preset height, maintain the jacking height, and the precision department shall measure the accuracy of the entire ship; Step 9. After completing the jacking operation, the general assembly department shall arrange personnel to replace the failed dock pier with the pre-prepared dock pier, and tighten the dock pier wood. Plastic film shall be laid on the upper surface of the pier wood to protect the bottom paint of the ship.At the same time, check whether the piers of other docks are tight. If they are loose, tighten the piers. Step 10: After all the piers are tightened, the jack is depressurized. The depressurization process needs to be carried out slowly. When 50% of the jacking weight is depressurized, stop depressurization and maintain pressure. At this time, measure the accuracy of the whole ship to see if it meets the requirements. If the accuracy does not meet the requirements, it is necessary to re-lift the jack. After the accuracy meets the requirements, install the semi-permanent steel pipe support. Step 11: After all the piers on the dock are tightened and the semi-permanent steel pipe support is installed, depressurize the jack. The depressurization process needs to be carried out slowly. When the pressure is close to 0, the jacking head stops falling. Step 12: The accuracy department checks the accuracy of the whole ship to see if it meets the expected accuracy requirements. If it does not meet the requirements, the ship needs to be re-lifted until it meets the expected accuracy requirements. Step 13: After the reset is completed, the jack is depressurized and the jacking head drops to separate it from the bottom of the ship.

[0007] Six 300-ton jacks and twenty-two 200-ton jacks are arranged under the six cross beams, and six 100-ton jacks are distributed gradually toward both sides of the hull near the middle, with each side having six 100-ton jacks.

[0008] The semi-permanent steel pipe support under the beam is welded and reinforced with the beam structure, and 100mm hard pier wood needs to be laid on the top of the semi-permanent steel pipe support under the bottom outer plate.

[0009] A 50mm flat pier wood needs to be laid on the top of the temporary steel support under the FR52-FR54 ribs on the bottom of the hull.

[0010] A steel plate and a height-adjusting cushion block are laid on the top of the jack under the crossbeam.

[0011] The jack at the bottom of the hull is installed with double steel plates, double piers and plastic films installed on the top of the jack in sequence according to the remaining space, until the top plastic film fits with the hull, and there is no risk of the double steel plates and double piers on the jack falling off.

[0012] The jack is a hydraulic jack with a rotatable ball head, and the rotation angle of the top ball head can adjust the eccentric load capacity to a maximum of ±5 degrees.

[0013] The number of jacks is 40, with 6 300-ton jacks and 22 200-ton jacks arranged under the crossbeam, and 6 100-ton jacks distributed gradually toward both sides near the middle, for a total of 12 jacks.

[0014] The slope adjustment and jacking in the eighth step adopts overall proportional synchronous slope adjustment, that is, all jacks on the same axis are jacked synchronously, and the jacks between different axes are linearly and synchronously jacked. The jacking speed is set according to the proportion of the jacking height. The specific method is: after all jacks are installed in place and debugged correctly, first set zero pressure to make all jacks fit with the bottom structure of the hull. This is the reference jacking line, set the jacking height ratio of the jacks of each axis, set the jacking height, the initial jacking height is 0.5~1mm, after the initial jacking, check whether the jacking height of each axis is increased according to the set ratio, confirm that it is correct, and then repeat the reciprocating cycle jacking synchronously, continuously increase the jacking height, and finally reach the predetermined height.

[0015] Beneficial effect: This method realizes the sinking and lifting reset of the inclined slipway hull through the combined action of the jack and the steel support, with the jack lifting and the steel support cooperating to support, ensuring that the hull reaches the specified position, and ensuring that the position of the shaft rudder system cable and the center line meet the design requirements through reset adjustment, and also ensuring the accuracy of the hull deflection measurement data. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 It is a schematic diagram of the structure of the present invention; Figure 2 This is an enlarged view of part A; Figure 3 This is an enlarged view of part B; Figure 4 This is an enlarged view of part C; Figure 5 Provide layout drawings for temporary steel support installation; Figure 6 Installation layout drawing for beams and jacks; Figure 7 It is a schematic diagram of the jack structure under the beam; Figure 8 Layout drawing for the installation of the boat bottom and jacks; Fig. 9 This is a schematic diagram of the jack structure under the ship; Fig.10 This is the installation layout drawing of beams 1 to 5 and semi-permanent steel pipe supports; Fig.11 Installation layout drawing for the No. 6 beam and semi-permanent steel pipe support; Fig.12 Installation layout for the ship bottom and semi-permanent steel pipe support; Fig.13 This is a schematic diagram of a semi-permanent steel pipe support structure; Fig.14 It is a flow chart of the present invention; Fig.15 This is a table of lifting height data for 40 jacks; Figure numerals: beam No. 1 1, beam No. 2 2, beam No. 3 3, beam No. 4 4, beam No. 5 5, beam No. 6 6, jack 15, temporary steel support 16, round tube support base 17, semi-permanent steel tube support 18, dock pier 19, hard pier 20, flat pier 21, steel plate 22, height adjustment pad 23, double steel plate 24, double pier 25. DETAILED DESCRIPTION

[0017] The present invention will be further described below in conjunction with the accompanying drawings and embodiments.

[0018] Embodiment 1: This time, the sinking part from the stern to the middle of about 67 meters of the slipway CHB5001 was lifted, and the maximum lifting height was about 92mm. When it was lifted to the same height as the planned, the dock pier was restored.

[0019] This lifting plan plans to use 40 jacks 15, as shown below Figure 2 and 3 As shown in the figure, 40 jacks 15 are arranged, among which there are six beams where the reaction force at the stern is concentrated. It is planned to set 4 300T jacks on the first beam 1, the jack body is 410mm high and the stroke is 150mm, the second beam 2 and the third beam 3 are equipped with 8 200T jacks, the jack body is 335mm high and the stroke is 150mm, the fourth beam 4, the fifth beam 5 and the sixth beam 6 are equipped with 12 300T jacks. The jack has a body height of 295mm and a stroke of 130mm. In addition, 6 100-ton jacks are gradually distributed on both sides near the middle. Specifically, FR41 is provided with 2 300T jacks, the body height of the jack is 410mm, and the stroke is 150mm. FR42 is provided with 2 200T jacks, the body height of the jack is 335mm, and the stroke is 150mm. FR43 to FR48 are provided with 12 100T jacks, the body height of the jack is 310mm, and the stroke is 150mm. When arranging 40 jacks 15, 18 Ø325*16mm temporary steel supports 16 with a height of 1786mm and 16 semi-permanent steel pipe supports are installed. The specific arrangement is as follows: Figure 2 , 3 , as shown in Figure 4.

[0020] The lifting operation process is as follows: First, the preparation work before lifting and resetting is carried out, and the tooling for the installation position of the jack 15 is prepared, including 18 temporary steel supports 16, 40 round tube support bases at the bottom of the jack 15, 16 semi-permanent steel pipe supports, 50 sets of dock piers 19 and supporting piers to be replaced, 40 20*300*300 steel jack head pads, several 10-18MM height adjustment pads, 24 25mm*300*500 piers (for the jack under the launching beam), 32 50MM*300*1300 piers (for the jack under the ship bottom), 16 35*600*600 steel pads, 4 100mm*300*1300 piers, several spare steel pipe supports (φ325*16) and other tooling, and cutting and welding equipment are arranged for emergency use. After the tooling is prepared, , clean the installation position of the jack 15, mark the position where the jack 15 is to be installed according to the jack 15 layout diagram, and clean the site where the jack 15 is to be installed to facilitate construction. Then, the prepared required tooling is delivered to the location first, and the dock pier 19 to be replaced and related materials are taken to the vicinity of the installation location. After completing the preliminary work, supervise the site safety, check whether there are construction personnel on board, arrange to evacuate the construction personnel on board, and set up the on-site equipment warning area, prohibiting unrelated personnel from entering the jacking construction site.

[0021] Each jack uses imported ultra-high pressure seals and dust rings to reduce pollution and extend the service life of the cylinder. The special load-bearing design can withstand lateral loads of 10% of the cylinder's load-bearing capacity without being damaged. Each jack is forged with high-quality high-strength alloy steel, heat-treated to increase strength, and subjected to multiple ultra-high wave non-destructive testing to ensure the material density of the parts and prevent cracks inside the cylinder. The piston rod is plated to increase strength and durability.

[0022] The hydraulic station adopts a hydraulically controlled throttle valve, which can individually adjust and lock the stroke and flow of each jack.

[0023] The linked hydraulic system is adopted so that each jack has an independent pressure gauge, which can accurately read the actual load (a silicone oil shockproof pressure gauge with an accuracy level of 0.4 is used. It is the window of the system and allows you to understand the operation of the system). To ensure the jacking accuracy, the jacking requirements are completed in stages. The lifting height of each jack can be adjusted manually or automatically, and the vehicle-mounted design is convenient for construction and movement.

[0024] The central controller is the master controller, that is, it controls the oil circuits for force transmission of all pump stations at the same time, controls the displacement height, and provides real-time feedback based on the pressure and height difference of each circuit, so that abnormalities can be discovered and dealt with in a timely manner during the jacking process.

[0025] The jack uses a hydraulic jack with a rotatable ball head (hydraulic jack with an inclined saddle), and the top ball head rotation angle can adjust the eccentric load capacity up to ±5 degrees. During the proportional slope adjustment and synchronous jacking process, as the slope of the upper structure changes, the hydraulic jack and the upper structure slowly change from vertical to non-vertical. At this time, the ball head on the top of the hydraulic jack will automatically adjust the top ball head as the slope of the upper structure changes to balance the deflection load and always keep the force surface vertical. Since this time we are working on a slipway with an inclination, the jack we use has good adaptability and can be used for the working conditions of the slipway with a slope of 1:21 and the superimposed hull 67M range from 0 vertical to -85mm.

[0026] After completing the preliminary work, enter the formal implementation process: All failed dock piers at the stern that can be removed need to be removed, and new piers should be installed in their original locations. Steel pipe supports should be used to reinforce the bottom of the beam. The steel pipes should be welded to the beam to prevent it from sinking again, and temporary supports should be added at other locations.

[0027] Install 18 temporary supports at FR52-FR54 ribs. The specific locations are as follows: Figure 4 As shown, a flat pier wood 21 of 50MM*300*1300 is laid on the top of the temporary steel support 16 under the FR52-FR54 ribs on the bottom of the hull.

[0028] After checking and testing the jack 15 and finding no problems, install the jack 15 on the round tube support base 17, the height of the round tube support base 17 under the No. 1 beam 1 is 473mm, the height of the round tube support base 17 under the No. 2 beam 2 and the No. 3 beam 3 is 552mm, the height of the round tube support base 17 under the No. 4 beam 4 and the No. 5 beam 5 is 619mm, the height of the round tube support base 17 under the No. 6 beam 6 is 577mm, the height of the round tube support base 17 under R41 is 1249mm, the height of the round tube support base 17 under R42 is 1327mm, the height of the round tube support base 17 under R43-R45 is 1363mm, and the height of the round tube support base 17 under R46-R47 is 535mm.

[0029] A steel plate 22 and a height adjustment pad 23 are laid on the top of the jack 15 under the beam. The size of the height adjustment pad at the first beam 1 is (10-20)*300*300mm, and the size of the height adjustment pad at the second beam 2 to the sixth beam 6 is (10-18)*300*300mm. The size of the steel plate 22 is 20*300*300mm.

[0030] The jack 15 at the bottom of the hull is installed with double steel plates 24, double piers 25 and plastic film in sequence on the top of the jack 15 according to the remaining space, until the top plastic film fits with the hull. There is no risk of falling of the double steel plates 24 and double piers 25 on the jack 15. The sizes of the two piers are 50*300*1300mm, the size of the upper steel plate is 35*600*600mm, and the size of the lower steel plate is 20*300*300mm.

[0031] After completing the installation of the jack 15, check whether the equipment and tooling used for jacking are in place and intact. The jacking operation can only be carried out after the jack 15 is pre-debugged and all the functions of the jack 15 are confirmed to be normal. During jacking, always pay attention to the status of the jack 15 and record the various data of the jack 15 during jacking in real time. At the same time, it should be noted that the jacking tonnage of the jack 15 in the 4500 area in the middle of the slipway slideway must be controlled within the range of 108T, and the jacking tonnage of the jack 15 on the slideway must be controlled within the range of 65T. During the jacking operation, the precision department must monitor the precision status of the entire ship in real time. The preset jacking height of each point of the hydraulic jack 15, the specific height data are as follows Fig.15 As shown, the jack stops lifting after reaching the predetermined lifting height, and the lifting height is maintained. The precision department measures the accuracy of the entire ship.

[0032] This slope adjustment and jacking adopts overall proportional synchronous slope adjustment, that is, all jacks on the same axis are lifted synchronously, and jacks between different axes are lifted linearly and synchronously, and the lifting speed is set according to the proportion of the lifting height.

[0033] Specifically: a. After all jacks are installed and debugged correctly, set the zero pressure first to make all jacks fit with the bottom structure of the hull. This is the reference jacking line; b. Set the lifting height ratio of the jacks of each axis; c. Set the lifting height, the initial setting is 0.5~1mm, and after the initial lifting, check whether the lifting height of each axis is increased according to the set ratio; d. After confirming that everything is correct, repeat the reciprocating cycle of lifting synchronously, continuously increase the lifting height, and finally reach the predetermined height.

[0034] After the jacking is completed, arrange the staff to replace the failed dock pier with the pre-prepared dock pier 19, and tighten the dock pier wood. Plastic film should be laid on the upper surface of the pier wood to protect the paint on the bottom of the ship. At the same time, check whether the pier wood of other dock piers 19 is tight. If there is any looseness, the pier wood needs to be tightened. After all the pier woods are tightened, the jack is depressurized. The depressurization process needs to be carried out slowly. When 50% of the jacking weight (about 2000T) is depressurized, stop depressurization and maintain pressure. At this time, measure the accuracy of the whole ship to see if it meets the requirements. If the accuracy does not meet the requirements, the jacking operation needs to be carried out again. After the accuracy meets the requirements, install the semi-permanent steel support. The height of the semi-permanent steel support under the No. 1 beam 1 to the No. 5 beam 5 is 930mm, and the semi-permanent steel support under the No. 6 beam 6 is 930mm. The height of the steel support is 980mm, and the height of the remaining semi-permanent steel supports under the bottom of the ship is 1343mm. The upper part of the semi-permanent steel support under the launching beam is not padded with piers, and is welded and reinforced with the launching beam structure. The top of the semi-permanent steel support under the outer plate of the bottom of the ship needs to be laid with a 100mm hard pier 20. After the piers on all the dock piers 19 are tightened and the semi-permanent steel supports are installed, the jack is depressurized. The depressurization process needs to be carried out slowly. When the pressure is close to 0, the hydraulic jack stops descending. The precision department checks the accuracy of the entire ship to see if it meets the expected accuracy requirements. If not, the ship needs to be re-lifted until the expected accuracy requirements are met. After the reset is completed, the jack is depressurized, and the jack is lowered to separate it from the bottom of the ship to complete the reset.

[0035] Although the present invention has been described in detail with reference to the aforementioned embodiments, it is still possible for those skilled in the art to modify the technical solutions described in the aforementioned embodiments, or to make equivalent substitutions for some of the technical features therein. 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 method for resetting the hull of an inclined berth by sinking and lifting, characterized in that: It includes a slipway, a hull, a lifting device and a tooling assembly. The lifting device includes a hydraulic pump station, a jack, a hydraulic pipeline, a central controller and a displacement sensor. The jack is connected to the hydraulic station through an oil circuit for force transmission. Each hydraulic pump station is connected through an electrical signal line and is controlled by the central controller to lift the target object. At the same time, the central controller receives the signal feedback from the displacement sensor to control the lifting height. The tooling assembly includes a number of temporary steel supports, a number of round tube support bases at the bottom of the jack, a number of semi-permanent steel pipe supports, a number of dock piers and accessories that need to be replaced. The pier wood, cutting equipment and welding equipment are installed. The jacks are located under the six beams at the stern reaction force concentration point of the hull and under the hull near the middle and gradually distributed to both sides. The jacks are installed on the upper end surface of the circular tube support base. The temporary steel support is installed under the hull. The semi-permanent steel pipe support is located under the hull and the beams. How to use: The first step is to prepare the jacking equipment and tooling components, and clean the installation position of the jack; the second step is to transport the prepared tooling components to the location first, and take the dock piers and related materials to be replaced to the vicinity of the installation location; The third step is to check whether there are construction personnel on board, arrange to evacuate the construction personnel on board, and set up the warning area for on-site equipment, and prohibit irrelevant personnel from entering the jacking construction site; the fourth step is to remove the failed dock pier at the stern and reinforce the original position with a pier support; the fifth step is to install 18 temporary steel supports at the FR52-FR54 ribs on the bottom of the hull; the sixth step is to check the number of jacks to be installed. After testing, install the jacks on the round tube support base, and install the adjustment components according to the remaining space to ensure that the adjustment components fit the hull and will not fall off; the seventh step is to prepare for jacking after the jacks are installed, and check the Whether the equipment and tooling are in place and intact, the jacks have been pre-debugged and confirmed that all jacks are functioning normally before the jacking operation can be carried out. During jacking, always pay attention to the status of the jacks and record the various data of the jacks during jacking in real time; Step 8. While performing the jacking operation, the precision department shall monitor the accuracy status of the entire ship in real time. The jack shall stop jacking after reaching the jacking height according to the preset height, maintain the jacking height, and the precision department shall measure the accuracy of the entire ship; Step 9. After completing the jacking operation, the general assembly department shall arrange personnel to replace the failed dock pier with the pre-prepared dock pier, and tighten the dock pier wood. Plastic film shall be laid on the upper surface of the pier wood to protect the bottom paint of the ship. At the same time, check whether the piers of other docks are tight. If they are loose, tighten the piers. Step 10: After all the piers are tightened, unload the pressure on the jack. The unloading process needs to be carried out slowly. When 50% of the jacking weight is unloaded, stop unloading and maintain the pressure. At this time, measure the accuracy of the entire ship to see if it meets the requirements. If the accuracy does not meet the requirements, it is necessary to re-lift the jack. After the accuracy meets the requirements, install the semi-permanent steel pipe support. Step 11: After all the piers on the dock are tightened and the semi-permanent steel pipe support is installed, unload the pressure on the jack. The unloading process needs to be carried out slowly. When the pressure is close to 0, the jacking head stops descending. In the twelfth step, the precision department checks the accuracy of the entire ship to see if it meets the expected precision requirements. If not, the ship needs to be re-lifted until it meets the expected precision requirements. In the thirteenth step, after the resetting is completed, the jack is depressurized and the jacking head is lowered to separate it from the bottom of the ship.

2. The method for sinking and lifting the inclined berth hull according to claim 1 is characterized in that: Six 300-ton jacks and twenty-two 200-ton jacks are arranged under the six cross beams, and six 100-ton jacks are distributed gradually toward both sides of the hull near the middle, with each side having six 100-ton jacks.

3. The method for sinking and lifting the inclined berth hull according to claim 1 is characterized in that: The semi-permanent steel pipe support under the beam is welded and reinforced with the beam structure, and 100mm hard pier wood needs to be laid on the top of the semi-permanent steel pipe support under the bottom outer plate.

4. The method for resetting the inclined berth by sinking and lifting the hull according to claim 1 is characterized in that: A 50mm flat pier wood needs to be laid on the top of the temporary steel support under the FR52-FR54 ribs on the bottom of the hull.

5. The method for resetting the inclined berth by sinking and lifting the hull according to claim 1 is characterized in that: A steel plate and a height-adjusting cushion block are laid on the top of the jack under the crossbeam.

6. The method for resetting the inclined berth by sinking and lifting the hull according to claim 1, characterized in that: The jack at the bottom of the hull is installed with double steel plates, double piers and plastic films installed on the top of the jack in sequence according to the remaining space, until the top plastic film fits with the hull, and there is no risk of the double steel plates and double piers on the jack falling off.

7. The method for sinking and lifting the inclined berth hull according to claim 1 is characterized in that: The jack is a hydraulic jack with a rotatable ball head, and the rotation angle of the top ball head can adjust the eccentric load capacity to a maximum of ±5 degrees.

8. The method for resetting the inclined berth by sinking and lifting the hull according to claim 1, characterized in that: The number of jacks is 40, with 6 300-ton jacks and 22 200-ton jacks arranged under the crossbeam, and 6 100-ton jacks distributed gradually toward both sides near the middle, for a total of 12 jacks.

9. The method for resetting the inclined berth by sinking and lifting the hull according to claim 1, characterized in that: The slope adjustment and jacking in the eighth step adopts overall proportional synchronous slope adjustment, that is, all jacks on the same axis are jacked synchronously, and the jacks between different axes are linearly and synchronously jacked. The jacking speed is set according to the proportion of the jacking height. The specific method is: after all jacks are installed in place and debugged correctly, first set zero pressure to make all jacks fit with the bottom structure of the hull. This is the reference jacking line, set the jacking height ratio of the jacks of each axis, set the jacking height, the initial jacking height is 0.5~1mm, after the initial jacking, check whether the jacking height of each axis is increased according to the set ratio, confirm that it is correct, and then repeat the reciprocating cycle jacking synchronously, continuously increase the jacking height, and finally reach the predetermined height.

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