A method for controlling the installation accuracy of a segmented base in a non-horizontal state

Abstract

This invention proposes a method for controlling the installation accuracy of segmented bases in non-horizontal states, comprising the following steps: before segment removal, mark the center line, rib inspection line, and horizontal inspection line, and mark the horizontal position in the engine room and mark the horizontal position; using a virtual elevation parallel to the base center line and a virtual plane parallel to the base installation surface as references, locate the width and length of the base, level the base panel, and determine the allowance at the bottom of the base; when establishing the virtual elevation and virtual plane, prioritize the location of strong structures and ensure that the coverage area is larger than the base to avoid accuracy errors; during the determination of the allowance at the bottom of the base, the cutting of the allowance at the bottom of the base should consider welding shrinkage compensation, determine the allowance of the base, complete the control of base installation accuracy, and eliminate the influence of segmentation in non-horizontal states on the installation accuracy of the base.

Description

Technical Field

[0001] This invention belongs to the field of shipbuilding technology, specifically relating to a method for controlling the installation accuracy of segmented bases in a non-horizontal state. Background Technology

[0002] In the shipbuilding industry, the installation of key foundations for large main engines and equipment on various types of ships is typically carried out on the jig during the sectional completion stage in a horizontal state. Due to limited jig space and short sectional construction cycles, the installation of large foundations on engine room sections is often scheduled after the section is removed from the jig and before it is mounted on the slipway. Because the section is no longer horizontal after being removed from the jig, the traditional approach for foundation installation is to first adjust the section to a satisfactory level. The process for adjusting the section to a satisfactory level is complex, and the steps are as follows: First, adjust the longitudinal levelness of the bottom plates at the bow and stern to the correct position. Then, adjust the center line of the upper opening with the center line of the bottom plate as a reference, ensuring that the alignment deviation meets ±2mm. Next, re-measure the deck side plates at the bow and stern ends (strong rib locations) of the section to ensure that the four corners of the deck are level and meet the standard requirements. Finally, erect a center line and foundation rib verification line frame on the inner bottom plate and set up a marker outside the section as a basis for foundation positioning. However, the segmented state is easily affected by cross-operations, especially the hoisting of heavy pallets, causing the segments to become non-horizontal again. The accuracy control of the base is difficult, and the repeated adjustment of the segmented state results in a lot of time loss and low overall efficiency. Summary of the Invention

[0003] To address the technical problems existing in the prior art, the present invention provides a method for controlling the installation accuracy of a segmented base in a non-horizontal state, which includes the following steps:

[0004] An elevation is established with the centerline inside the cabin as the reference, and this elevation serves as the width reference for the base installation.

[0005] Position the reference centerline, measure the centerline surface of the base, adjust it to be parallel to the newly established surface, and ensure that the distance between the centerline of the base and the center meets the tolerance requirements.

[0006] Then measure the base inspection ribs and adjust them to align with the corresponding ribs of the segments;

[0007] A virtual plane is established inside the cabin based on the theoretical height of the base panel, and this plane serves as the height reference for the base installation.

[0008] First, adjust the base panel plane to be parallel to the virtual reference plane, measure the parallel data between the reference plane and the base plane, and adjust the base according to the drawing data.

[0009] Survey and mark the remaining space at the bottom of the base and complete the cutting;

[0010] The base with no margin was repositioned, and the accuracy of the base installation was finally controlled.

[0011] Furthermore, the elevation of the centerline inside the cabin is established based on measurement point one, measurement point two, and measurement point three; the selected locations of measurement point one, measurement point two, and measurement point three are respectively in the front, rear, and upper areas of the bottom or platform plate inside the cabin, and are marked.

[0012] Furthermore, the center line of the measuring base is measured, and a system is established based on measuring points four, five, and six; among which measuring points four, five, and six are all located on the center line of the measuring base.

[0013] Furthermore, the theoretical height of the base panel is a virtual plane, which is established based on measurement points seven, eight, and nine. The locations of measurement points seven, eight, and nine are as follows: one point is taken at the bow or stern position inside the engine room, and the other two points are taken at one point each on the port and starboard outer sides, and they are marked.

[0014] Furthermore, to ensure the accuracy of the base installation, a virtual elevation parallel to the base centerline and a virtual plane reference parallel to the base installation surface, which were originally established on the segment, are used for verification.

[0015] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0016] This invention is applicable to the precision control of segmented bases in all non-horizontal states, and is also suitable for base installation in other industries with high precision requirements. In installation operations where the ground level is disrupted, it can greatly reduce positioning time, lower quality risks, and improve the efficiency of base installation precision. Attached Figure Description

[0017] Figure 1 This is the first view of the invention and an elevation view is established;

[0018] Figure 2 This is a top view of the invention and a schematic diagram of the corresponding ribs in the base inspection rib alignment segment;

[0019] Figure 3 This is a front view of the present invention and a schematic diagram of a virtual plane.

[0020] Figure 4 This is a schematic diagram showing the allowance H at the bottom of the base for this invention. Detailed Implementation

[0021] To enable those skilled in the art to better understand the technical solution of the present invention, the present invention will be further described below in conjunction with the accompanying drawings and specific embodiments.

[0022] Reference Figures 1-4 The method for controlling the installation accuracy of segmented bases in non-horizontal states proposed in this application specifically includes the following steps:

[0023] 1. Establish an elevation based on the centerline inside the cabin (e.g., establish a system by measuring points 1, 2, and 3). This elevation will serve as the width reference for the base installation. Select the locations of points 1, 2, and 3 on the front, rear, and upper areas of the bottom or platform inside the cabin, and mark them accordingly.

[0024] 2. Locate the center line of the base, measure the center line surface of the base (e.g., measure points 4, 5, and 6 on the center line of the base), adjust it to be parallel to the newly built facade, and ensure that the distance between the center line of the base and the center meets the tolerance requirements;

[0025] 3. Then measure the inspection ribs of the base and adjust them to align with the corresponding ribs of the segment;

[0026] 4. Establish a virtual plane in the engine room based on the theoretical height of the base panel (Note: for the convenience of on-site operation, it is generally moved upwards) (e.g., measure points 7, 8, and 9 to establish the system). This plane will serve as the height reference for the base installation. Take one point in the engine room near the bow / stern and the other two points on the port and starboard outer sides, and mark them.

[0027] 5. First, adjust the base panel plane to be parallel to the virtual reference plane, measure the parallel data between the reference plane and the base plane, and adjust the base according to the drawing data (base bottom allowance H).

[0028] 6. Survey and mark the remaining space at the bottom of the base and complete the cutting;

[0029] 7. Reposition the base without margin, and use a virtual elevation parallel to the center line of the base and a virtual plane reference parallel to the mounting surface of the base established on the original segment for verification, and finally complete the base installation accuracy control.

[0030] Before segmented demolding, the present invention requires the establishment of center lines, rib inspection lines, and horizontal inspection lines. Horizontal markings should also be made and punched within the engine room at the base installation location. Using a virtual elevation parallel to the base centerline and a virtual plane parallel to the base installation surface as references, the width and length of the base are positioned, the base panel is leveled, and the lower edge allowance is determined. When establishing the virtual elevation and virtual plane, the three points selected should prioritize locations with strong structural features and have a coverage area larger than the base to avoid accuracy errors. During the determination of the lower edge allowance, welding shrinkage compensation should be considered when cutting the lower edge allowance. Determining the base allowance and completing the base installation accuracy control eliminates the influence of segmentation under non-horizontal conditions on the base installation accuracy.

[0031] In summary, these are merely preferred embodiments of the present invention and are not intended to limit the scope of protection of the present invention. All equivalent changes and modifications made in accordance with the scope of the present invention and the contents of the specification are within the scope of the present invention.

Claims

1. A method for controlling the installation accuracy of a segmented base in a non-horizontal state, characterized in that, Includes the following steps: An elevation is established with the centerline inside the cabin as the reference, and this elevation serves as the width reference for the base installation. Position the reference centerline, measure the centerline surface of the base, adjust it to be parallel to the newly established surface, and ensure that the distance between the centerline of the base and the center meets the tolerance requirements. Then measure the base inspection ribs and adjust them to align with the corresponding ribs of the segments; A virtual plane is established inside the cabin based on the theoretical height of the base panel. This virtual plane serves as the height reference for the base installation. First, adjust the base panel plane to be parallel to the virtual plane, measure the parallel data between the reference plane and the base plane, and adjust the base according to the drawing data. Survey and mark the remaining space at the bottom of the base and complete the cutting; Reposition the base with no margin to achieve final accuracy control of base installation; The elevation of the centerline inside the cabin is established based on measurement point one, measurement point two, and measurement point three; the selected locations of measurement point one, measurement point two, and measurement point three are respectively in the front, rear, and upper areas of the bottom or platform plate inside the cabin, and are marked. The center line of the base is measured, and a system is established based on measurement points four, five, and six; among which measurement points four, five, and six are all located on the center line of the base. The theoretical height of the base panel is a virtual plane, and a system is established based on measurement points seven, eight, and nine. The locations of measurement points seven, eight, and nine are as follows: one point is taken at the bow or stern position inside the engine room, and the other two points are taken at one point each on the port and starboard outer sides, and they are marked.

2. The method according to claim 1, characterized in that, To ensure the accuracy of the base installation, a virtual elevation parallel to the base centerline and a virtual plane reference parallel to the base installation surface were established on the original segment for verification.

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