Ship shafting rudder system center line positioning method

Abstract

The invention provides a ship shafting rudder system center line positioning method, which is suitable for a ship which is completely constructed in shafting engineering and is not provided with rudder system sections, and comprises the following steps of: firstly, acquiring the shafting center line of the ship, and then installing the rudder system sections according to the position of the shafting center line, so that the rudder system center line is vertically intersected with the shafting center line; and finally, the perpendicularity of the rudder system center line and the intersection degree of the rudder system center line and the shafting center line are detected. According to the positioning method provided by the invention, the rudder system section can be accurately positioned and mounted after shafting engineering construction is finished, so that the center line of the rudder system and the center line of the shafting meet the requirement of vertical intersection; in addition, the rudder system sections are hoisted after being refined in the workshop infield, so that the integrity of out-of-dock fitting-out is improved; the work of shafting rudder system center line positioning, boring shaft plugging and the like can be carried out without waiting for a stern structure to be completed, the work progress of ship outfitting is improved, and therefore the requirement for quick construction of wharf ships is met.

Description

Technical Field

[0001] The invention belongs to the technical field of shipbuilding, and specifically relates to a method for locating the center line of a ship shaft system and rudder system. Background Art

[0002] In shipbuilding, the construction of shafting and rudder systems is an extremely critical operation process, and its operation accuracy and correctness play a decisive role in the actual operation of the ship.

[0003] Historically, major classification societies and shipowners have extremely high requirements for the construction conditions of shafting and rudder systems. Before locating the centerline of the shafting and rudder systems, all hull structures and foundations from the front bulkhead of the engine room to the rear, below the main deck or the strong continuous deck, should be welded and corrected. The stern tube should be welded according to the qualified hull centerline, and the stern tube, cooling water tank and double bottom tank tightness test should be completed. According to the traditional construction method, the centerline of the shafting and rudder system can only be located, the shaft can be bored and plugged, and the main engine can be hoisted after the hull structure at the rear of the engine room is completed, which greatly delays the progress of the ship's outfitting work, and the integrity of the ship's out-of-dock outfitting cannot be guaranteed, which affects the dock cycle and cannot meet the needs of rapid construction of dock ships.

[0004] Large container ships generally use fully suspended rudders. This type of rudder system is different from other types of rudder systems. It does not require boring before installing the rudder stock. All parts are refined in the workshop. The installation accuracy requirements on the ship are inseparable from the mounting positioning technology in the hull structure. The traditional centerline positioning of the shaft system and rudder system is to bore the shaft system and rudder system after lighting. If there is a slight positioning deviation, the deviation can be compensated by the boring allowance. However, the fully suspended rudder is to accurately locate the total section of the rudder system structure after the shaft system construction is completed, so a new method needs to be found to make the centerline of the rudder system and the centerline of the shaft system meet the requirements of vertical intersection. Summary of the invention

[0005] In view of the shortcomings of the prior art described above, the present invention provides a method for locating the centerline of a ship's shafting and rudder system, which is suitable for ships whose shafting projects have been completely constructed but whose rudder system segments have not yet been installed. First, the centerline of the ship's shafting is obtained, and then the rudder system segments are installed according to the position of the shafting centerline, so that the rudder system centerline and the shafting centerline intersect vertically, and finally the verticality of the rudder system centerline and the intersection degree of the rudder system centerline and the shafting centerline are checked. The positioning method provided by the present invention can accurately locate and install the rudder system segments after the construction of the shafting project is completed, so that the rudder system centerline and the shafting centerline meet the requirement of vertical intersection; in addition, the rudder system segments are hoisted after being refined in the workshop, which improves the integrity of the out-of-dock outfitting; there is no need to wait until the stern structure is completed before the shafting and rudder system centerline positioning, boring and plugging the shaft, etc., which improves the work progress of the ship's outfitting, thereby meeting the needs of rapid construction of dock ships.

[0006] To achieve the above-mentioned and other related purposes, the present invention provides a method for locating the centerline of a ship shafting and rudder system, comprising the following steps:

[0007] Acquire a shaft centerline of the ship, and form a stern shaft hole with the shaft centerline as the center, wherein intersection points of the shaft centerline and two end surfaces of the stern shaft hole are respectively a first center point and a second center point, and the second center point is located inside the engine room;

[0008] Projecting the first center point and the second center point longitudinally to obtain a projection extension line of the axis center line on the dock bottom;

[0009] Installing a stern tube in the stern shaft hole, installing the rudder system segment with reference to the projection extension line of the shaft system center line, so that the rudder system center line intersects the projection extension line of the shaft system center line perpendicularly;

[0010] Check the verticality of the centerline of the rudder system and the intersection of the centerline of the rudder system with the centerline of the shaft system.

[0011] Optionally, the deformation law of the center line of the shaft system is obtained through finite element analysis, and the center line of the shaft system is obtained according to the law.

[0012] Optionally, the first center point and the second center point are first projected longitudinally to the bottom outer plate of the ship to form a mark, and after half of the ship is dropped on the pier, the projection extension line of the center line of the shafting is obtained on the dock bottom based on the mark.

[0013] Optionally, after obtaining the projection extension line of the shaft system centerline, the method further includes: marking the horizontal height of the first center point on the outside of the stern shaft hole to form a horizontal marking line.

[0014] Optionally, at the height of the horizontal marking line, the distance between the center line of the rudder system and the center line of the shaft system is measured to check the intersection of the two.

[0015] Optionally, the verticality of the rudder system centerline includes verticality in a first direction and verticality in a second direction, the first direction being a direction parallel to the shaft system centerline, and the second direction being perpendicular to the first direction in the same horizontal plane.

[0016] Optionally, a laser instrument is arranged at the intersection of the center line of the rudder system and the center line of the shaft system. The laser instrument emits laser from bottom to top, measures the horizontal distance between the upper and lower edges of the rudder cylinder and the laser in the first direction to calculate the verticality in the first direction, and measures the horizontal distance between the upper and lower edges of the rudder cylinder and the laser in the second direction to calculate the verticality in the second direction.

[0017] The centerline positioning method of the ship shafting and rudder system provided by the present invention has at least the following beneficial effects:

[0018] The positioning method provided by the present invention can accurately position and install the rudder system segment after the shaft system construction is completed, so that the center line of the rudder system meets the requirement of vertical intersection with the center line of the shaft system; in addition, the rudder system segment is hoisted after being refined in the workshop, which improves the integrity of the out-of-docking outfitting; there is no need to wait until the stern structure is completed before performing the work of center line positioning of the shaft system and rudder system, boring and plugging the shaft, etc., which improves the work progress of the ship outfitting, thereby meeting the demand for rapid construction of dock ships. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 Shown is a schematic diagram of the complete structure of the stern of a ship provided in an embodiment.

[0020] Figure 2 Shown is a schematic diagram of an incomplete stern structure of a ship provided in an embodiment.

[0021] Figure 3 A side view of the shafting area of ​​a vessel provided for an embodiment is shown.

[0022] Figure 4 A rear view of the shafting area of ​​a vessel provided for an embodiment is shown.

[0023] Figure 5 The diagram shown is a schematic diagram of obtaining the projection extension line of the shafting centerline on the dock bottom provided in an embodiment.

[0024] Figure 6 A diagram showing the arrangement of laser instruments provided for an embodiment is shown.

[0025] Figure 7a to Figure 7b Shown is a schematic diagram of the upper and lower end surfaces of the rudder cylinder provided in an embodiment.

[0026] Figure 8 Shown is a schematic diagram of checking the degree of intersection between the rudder system centerline and the shaft system centerline provided by an embodiment.

[0027] Component number description

[0028] 1 Stern shaft hole

[0029] 100 Shaft centerline

[0030] 101 Shaft centerline projection extension line

[0031] 11 First Center Point

[0032] 12 Second center point

[0033] 111 First Mark

[0034] 121 Second Mark

[0035] 110 horizontal marking line

[0036] 2 Rudder system sections

[0037] 200 Rudder centerline

[0038] 3 Stern tube

[0039] 4 Laser

[0040] 5 Rudder DETAILED DESCRIPTION

[0041] The following describes the embodiments of the present invention through specific examples, and those skilled in the art can easily understand other advantages and effects of the present invention from the contents disclosed in this specification. The present invention can also be implemented or applied through other different specific embodiments, and the details in this specification can also be modified or changed in various ways based on different viewpoints and applications without departing from the spirit of the present invention.

[0042] It should be noted that the illustrations provided in this embodiment only illustrate the basic concept of the present invention in a schematic manner. Although the illustrations only show components related to the present invention rather than being drawn according to the number, shape and size of components in actual implementation, the form, quantity, positional relationship and proportion of each component in actual implementation can be changed at will under the premise of realizing the technical solution of this party, and the component layout form may also be more complicated.

[0043] Example

[0044] This embodiment provides a method for locating the centerline of a ship shaft system and rudder system, comprising the following steps:

[0045] Step S1: obtaining a shaft centerline of the ship, forming a stern shaft hole with the shaft centerline as the center, the intersection points of the shaft centerline and the two end surfaces of the stern shaft hole are respectively a first center point and a second center point, and the second center point is located inside the cabin;

[0046] As an example, the positioning method provided in this embodiment is applicable to a large container ship with an incomplete stern structure, such as Figure 2 As shown, the shafting project of the ship has been completed, and the rudder system sections have not yet been hoisted.

[0047] First, the deformation law of the centerline of the shaft system is obtained through finite element analysis, and the centerline of the shaft system is obtained according to the law. Generally speaking, after the rudder system is hoisted in sections, the centerline of the shaft system will be offset. Therefore, the deformation of the shaft system area structure before and after hoisting is first analyzed by finite element analysis to obtain the deformation law of the centerline of the shaft system caused by the structural deformation. Then, according to the law, the accuracy control standard of the shaft system section, the support disassembly and assembly process standard of the engine room and tail area, the dock pier layout and inspection standard, the shaft rudder system wire pulling and lighting operation standard and other standards are formulated, so as to design the position of the centerline of the shaft system. In this embodiment, the analysis of the deformation of the shaft system area structure includes finite element analysis of the half-ship floating area, the stern bearing tube, the intermediate shaft and the dock pier structure.

[0048] As an example, the center line of the ship's shafting can be obtained by using a wire drawing method, an optical method, a projector illumination method, etc., and then a stern shaft hole is formed by boring with the center line of the shafting as the center.

[0049] like Figure 3 As shown, the intersection points of the shaft centerline 100 and the two end surfaces of the stern shaft hole 1 are the first center point 11 and the second center point 12, respectively, wherein the first center point 11 is close to the stern, and the second center point 12 is located inside the cabin.

[0050] Step S2: longitudinally projecting the first center point and the second center point to obtain a projection extension line of the axis center line on the dock bottom;

[0051] First, the first center point 11 and the second center point 12 are longitudinally projected onto the bottom outer plate of the ship to form a mark. Figure 3 and Figure 4 As shown, a light target can be arranged at the front and rear ends of the stern shaft hole 1 to determine the positions of the first center point 11 and the second center point 12, and then the first center point 11 and the second center point 12 are longitudinally projected to the bottom outer plate of the ship, and the bottom outer plate of the ship is marked with a punch to form a first mark 111 and a second mark 121.

[0052] Then, if Figure 5 As shown, after half of the ship is dropped on the pier, the first mark 111 and the second mark 121 are projected longitudinally to obtain a projection extension line 101 of the center line of the shaft system on the dock bottom.

[0053] Then, if Figure 4 As shown, the horizontal height of the first center point 11 is marked on the outside of the stern shaft hole 1 to form a horizontal marking line 110.

[0054] Step S3: installing the stern tube in the stern shaft hole, and installing the rudder system segment with reference to the projection extension line of the shaft system center line, so that the rudder system center line intersects the projection extension line of the shaft system center line perpendicularly;

[0055] like Figure 1As shown, the stern tube 3 is installed in the stern shaft hole, and the rudder system segment 2 is installed with reference to the projection extension line 101 of the shaft centerline. As an example, the rudder system segment 2 is installed with reference to the projection extension line 101 of the shaft centerline, so that the rudder system centerline 200 intersects the shaft centerline 100 vertically, which can ensure the normal operation of the steering gear, so that the ship can accurately respond to the rudder command and achieve precise steering.

[0056] Step S4: Check the verticality of the centerline of the rudder system and the intersection of the centerline of the rudder system with the centerline of the shaft system.

[0057] As an example, the verticality of the rudder system centerline includes verticality in a first direction and verticality in a second direction, wherein the first direction is a direction parallel to the shaft system centerline 100 , and the second direction is perpendicular to the first direction in the same horizontal plane.

[0058] like Figure 6 As shown, a laser instrument 4 is arranged at the intersection of the rudder system centerline 200 and the shaft system centerline 100, and the laser instrument 4 emits laser light from bottom to top. Figure 7a-7b As shown, the height of the rudder barrel 5 is H, and the horizontal distances L3 and L4 between the upper edge of the rudder barrel 5 and the laser in the first direction, as well as the horizontal distances L7 and L8 between the lower edge of the rudder barrel 5 and the laser in the first direction are measured. The verticality in the first direction is calculated according to formula (1):

[0059]

[0060] Measure the horizontal distances L1 and L2 between the upper edge of the rudder tube and the laser in the second direction, as well as the horizontal distances L5 and L6 between the lower edge of the rudder tube and the laser in the second direction, and calculate the verticality in the second direction according to formula (2):

[0061]

[0062] like Figure 8 As shown, a steel wire is used to connect the center point O1 of the upper end face of the rudder tube 5 and the center point O2 of the lower end face and extend to the bottom of the dock to simulate the center line 200 of the rudder system. At the height of the horizontal mark line 110, a total station is used to measure the distance D between the center line 200 of the rudder system and the center line 100 of the shaft system to check the intersection of the two.

[0063] As an example, the verticality of the rudder system centerline 200 is qualified if it is less than or equal to 1mm / m, that is, on the rudder system centerline 200, for every 1m difference in height, the horizontal deviation is less than or equal to 1mm; the intersection degree D of the rudder system centerline 200 and the shaft system centerline 100 is qualified if it is less than or equal to 8mm, and preferably, the intersection degree D is less than or equal to 5mm.

[0064] Through the positioning method provided in this embodiment, the installation of the tail shaft and propeller of a large container ship can be completed before floating, which shortens the construction period by about 25 days compared to starting the shaft system project after the stern structure is completed; the positioning method provided in this embodiment can enable the rudder system sections to be hoisted after they are refined in the workshop, thereby improving the integrity of the out-of-docking outfitting; the positioning method provided in this embodiment shortens the dock mooring period from 150 days to 120 days, thereby meeting the needs of rapid construction of dock ships.

[0065] The above embodiments are merely illustrative of the principles and effects of the present invention, and are not intended to limit the present invention. Anyone familiar with the art may modify or alter the above embodiments without departing from the spirit and scope of the present invention. Therefore, all equivalent modifications or alterations made by a person of ordinary skill in the art without departing from the spirit and technical concept disclosed by the present invention shall still be covered by the claims of the present invention.

Claims

1. A method for locating the centerline of a ship's shafting and rudder system, characterized in that: The steps include: Acquire a shaft centerline of the ship, and form a stern shaft hole with the shaft centerline as the center, wherein intersection points of the shaft centerline and two end surfaces of the stern shaft hole are respectively a first center point and a second center point, and the second center point is located inside the engine room; Projecting the first center point and the second center point longitudinally to obtain a projection extension line of the axis center line on the dock bottom; Installing a stern tube in the stern shaft hole, installing the rudder system segment with reference to the projection extension line of the shaft system center line, so that the rudder system center line intersects the projection extension line of the shaft system center line perpendicularly; Check the verticality of the centerline of the rudder system and the intersection of the centerline of the rudder system with the centerline of the shaft system.

2. The method for locating the centerline of a ship shafting and rudder system according to claim 1, characterized in that: The deformation law of the center line of the shaft system is obtained through finite element analysis, and the center line of the shaft system is obtained according to the law.

3. The method for locating the centerline of a ship shafting and rudder system according to claim 1, characterized in that: First, the first center point and the second center point are longitudinally projected to the bottom outer plate of the ship to form a mark. After half of the ship is dropped on the pier, the projection extension line of the center line of the shaft system is obtained on the dock bottom according to the mark.

4. The method for locating the centerline of a ship shafting and rudder system according to claim 1, characterized in that: After obtaining the projection extension line of the shaft system centerline, the method further includes: marking the horizontal height of the first center point on the outside of the stern shaft hole to form a horizontal marking line.

5. The method for locating the centerline of a ship shafting and rudder system according to claim 4, characterized in that: At the height of the horizontal marking line, the distance between the center line of the rudder system and the center line of the shaft system is measured to check the intersection of the two.

6. The method for locating the centerline of a ship shafting and rudder system according to claim 1, characterized in that: The verticality of the rudder system centerline includes verticality in a first direction and verticality in a second direction, wherein the first direction is a direction parallel to the shaft system centerline, and the second direction is perpendicular to the first direction in the same horizontal plane.

7. The method for locating the centerline of a ship shafting and rudder system according to claim 6, characterized in that: A laser instrument is arranged at the intersection of the center line of the rudder system and the center line of the shaft system. The laser instrument emits laser from bottom to top, measures the horizontal distance between the upper and lower edges of the rudder cylinder and the laser in the first direction to calculate the verticality of the first direction, and measures the horizontal distance between the upper and lower edges of the rudder cylinder and the laser in the second direction to calculate the verticality of the second direction.

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