Method for replacing traditional paddle shaft blue oil brushing

Abstract

The invention discloses a method for replacing traditional paddle shaft blue oil matching. The method comprises the following steps of 1, 3D scanning and curved surface reconstruction, wherein S1, a 3D scanner is selected; s2, 3D scanning is carried out; S3, curved surface reconstruction is carried out; step 2, contact condition analysis: S1, model alignment; s2, detecting a contact surface; s3, contact force analysis; s4, outputting and reporting a result; according to the method, the matching condition of the propeller hub and the shaft taper end of the propeller is accurately analyzed through the 3D scanning and curved surface reconstruction technology, the method is easy and convenient to operate and high in precision, the precision and efficiency of propeller installation can be remarkably improved, the maintenance cost is reduced, and the safety and stability of ship operation are improved.

Description

Technical Field

[0001] The present invention belongs to the technical field of ship engineering, and specifically relates to a method for replacing the traditional blue oil fitting of the propeller shaft. Background Art

[0002] The traditional blue oil fitting method of the propeller shaft has problems such as complex operation and limited accuracy, and it is difficult to meet the high requirements of modern ships for the installation accuracy of the propeller. Therefore, it is particularly important to develop an efficient and accurate fitting analysis method.

[0003] Based on this, a method for replacing the traditional blue oil fitting of the propeller shaft is designed. Summary of the Invention

[0004] In view of the above situation, in order to overcome the defects of the prior art, the present invention provides a method for replacing the traditional blue oil fitting of the propeller shaft, effectively solving the problems raised in the background art.

[0005] To achieve the above object, the present invention provides the following technical solution: A method for replacing the traditional blue oil fitting of the propeller shaft, comprising the following steps:

[0006] Step 1: 3D Scanning and Surface Reconstruction

[0007] S1. Select a 3D scanner:

[0008] Select a suitable 3D scanner according to the size of the propeller and the limitations of the scanning environment;

[0009] S2. Conduct 3D scanning:

[0010] Use a 3D scanner to scan the inner hole of the propeller hub and the tapered end of the shaft, ensuring that the surface of the object is clean and unobstructed during the scanning process, and keeping it as stationary as possible;

[0011] S3. Surface reconstruction:

[0012] Import the scanned three-dimensional data into a professional three-dimensional modeling software, and use the surface reconstruction function in the software to generate a three-dimensional surface model of the object according to the point cloud data;

[0013] Step 2: Contact Situation Analysis

[0014] S1. Model alignment:

[0015] Import the three-dimensional surface models of the inner hole of the propeller hub and the tapered end of the shaft into the same coordinate system, ensuring that their axial positions are consistent with the actual situation;

[0016] S2. Contact surface detection:

[0017] Using the Boolean operation or collision detection function of the software, simulate the contact situation between two surfaces. By slightly adjusting the relative position of the objects, observe the contact surface, contact points and possible interference areas between them;

[0018] S3. Contact force analysis:

[0019] Although the 3D scanning technology itself cannot directly measure the contact force, the magnitude and direction of the contact force can be indirectly evaluated by analyzing the shape, size and position of the contact surface, combined with factors such as the material and weight of the object or the starting point pressure; Finite element analysis software can also be used to simulate the contact and force conditions between objects, so as to obtain more accurate analysis results;

[0020] S4. Result output and report:

[0021] Output the analysis results in the form of a 3D model, 2D drawings or a report for subsequent grinding or repair work;

[0022] In the report, the position, size, shape of the contact surface and possible interference or wear conditions can be described in detail, and corresponding improvement suggestions can be put forward.

[0023] Preferably, in step one, for S1, when selecting a 3D scanner, for medium and large-sized propeller surfaces, a handheld laser 3D scanner can be selected.

[0024] Preferably, in step one, for S2, when performing 3D scanning, according to the shape and size of the object, multiple scans need to be performed from different angles to obtain complete 3D data.

[0025] Preferably, in step one, for S3, when performing surface reconstruction, the 3D modeling software is one of SolidWorks, Preo or 3DMax.

[0026] Preferably, in step two, for S1, when aligning the models, axis centerline alignment can be selected, and the calculated value of the press-fit amount when the distance between the large end face of the hub and the large end face of the shaft taper is at a temperature of 15 °C is used as the relative position of the two models;

[0027] The alignment function of the software can also be used to achieve precise circumferential alignment of the models by selecting common feature points or surfaces.

[0028] Compared with the prior art, the beneficial effects of the present invention are:

[0029] The present invention realizes the precise analysis of the matching situation between the propeller hub and the shaft taper end through 3D scanning and surface reconstruction technology. This method is easy to operate, has high precision, can significantly improve the installation precision and efficiency of the propeller, reduce the maintenance cost, and enhance the safety and stability of ship operation. Description of the Drawings

[0030] The accompanying drawings are used to provide a further understanding of the present invention and form a part of the specification. Together with the embodiments of the present invention, they are used to explain the present invention and do not constitute a limitation to the present invention.

[0031] In the accompanying drawings:

[0032] Figure 1 is a schematic flow chart of a method for replacing the traditional blue oil scraping and fitting of a propeller shaft according to the present invention

[0033] Figure 2 is a schematic diagram of model alignment in a method for replacing the traditional blue oil scraping and fitting of a propeller shaft according to the present invention;

[0034] Figure 3 is a schematic diagram of the expansion of the model contact surface in a method for replacing the traditional blue oil scraping and fitting of a propeller shaft according to the present invention; Detailed implementation manners

[0035] The following will clearly and completely describe the technical solutions in the embodiments of the present invention with reference to the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments; based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the scope of protection of the present invention.

[0036] Embodiment 1, given by Figures 1-3 The present invention relates to a method for replacing the traditional blue oil scraping and fitting of a propeller shaft, including the following steps:

[0037] Step 1. 3D scanning and surface reconstruction

[0038] S1. Select a 3D scanner:

[0039] Select a suitable 3D scanner according to the size of the propeller and the limitations of the scanning environment;

[0040] S2. Perform 3D scanning:

[0041] Use a 3D scanner to scan the inner hole of the propeller hub and the tapered end of the shaft, ensuring that the surface of the object is clean and unobstructed during the scanning process, and keeping it as stationary as possible;

[0042] S3. Surface reconstruction:

[0043] Import the scanned three-dimensional data into professional three-dimensional modeling software, and use the surface reconstruction function in the software to generate a three-dimensional surface model of the object according to the point cloud data;

[0044] Step 2. Analysis of contact conditions

[0045] S1. Model alignment:

[0046] Import the 3D surface models of the hub inner hole and the tapered end of the shaft into the same coordinate system to ensure that their axial positions are consistent with the actual situation;

[0047] S2. Contact surface detection:

[0048] Utilize the Boolean operation or collision detection function of the software to simulate the contact situation between the two surfaces. By slightly adjusting the relative positions of the objects, observe the contact surface, contact points, and possible interference regions between them;

[0049] S3. Contact force analysis:

[0050] Although the 3D scanning technology itself cannot directly measure the contact force, the magnitude and direction of the contact force can be indirectly evaluated by analyzing the shape, size, and position of the contact surface, combined with factors such as the material and weight of the object or the starting point pressure; Finite element analysis software can also be used to simulate the contact and force conditions between objects to obtain more accurate analysis results;

[0051] S4. Result output and report:

[0052] Output the analysis results in the form of 3D models, 2D drawings, or reports for subsequent grinding or repair work;

[0053] In the report, the position, size, shape of the contact surface, and possible interference or wear conditions can be described in detail, and corresponding improvement suggestions can be put forward.

[0054] The unfolded view of the contact surface is shown in Figure 3 , and a plane coordinate system is established for research and analysis

[0055] Define input elements:

[0056] (1). Z1, Z2, Z3... Collision points of the dimensions of the propeller hub and the tail shaft

[0057] (2). N Number of collision points

[0058] (3). S1: Contact surface of the Z1 collision point

[0059] S2-: Contact surface of the Z2 collision point

[0060] S3: Contact surface of the Z3 collision point

[0061] ...

[0062] Sn: Contact surface of the Zn collision point

[0063] (4). Total contact surface of the collision points ∑S = S1 + S2 + S3 +... + Sn

[0064] (5), D1: The large end diameter of the contact surface

[0065] (6), D2: The small end diameter of the contact surface

[0066] (7), SP: 100% contact surface with no collision occurring under ideal conditions

[0067] (8), L2: The theoretical press-in amount of the propeller at 15°C, calculated from ship specifications

[0068] (9), L1: The axial contact length of the propeller hub and the tapered section of the tail shaft (10) L3: The effective contact surface length

[0069] (11), D: The diameter of the tail shaft

[0070] (12), θ: Taper, generally taken as 1 / 20

[0071] Detection standard: Ship specifications require that the contact area should be not less than 70% of the theoretical contact area (100%). The non-contact zone should not surround the entire hub or extend along the entire length of the hub.

[0072] D1 = D - L2 * θ

[0073] D2 = D - (L1 + L2) * θ

[0074] SP = π * (D1 + D2) * L1 * 1 / 2

[0075]

[0076] If ∑S / SP > 70%, the inspection fails;

[0077] n = 1, 2, 3…, if (X′n - Xn) ≥ D1 * π, the inspection fails;

[0078] 3. n = 1, 2, 3…, if (Y′n - Yn) ≥ L3, the inspection fails;

[0079] If any one of 1 or 2 or 3 passes the inspection, the result is that the inspection fails.

[0080] In step one of this embodiment, for S1, a 3D scanner is selected. For medium and large-sized propeller surfaces, a handheld laser 3D scanner can be selected. Such as the KSCAN-Magic series from Scantech or the XTOM-MATRIX high-precision 3D scanner from Newtop 3D. These devices have the characteristics of high precision, portability, and easy operation.

[0081] In step one of this embodiment, for S2, 3D scanning is carried out. According to the shape and size of the object, multiple scans need to be performed from different angles to obtain complete three-dimensional data.

[0082] In step one of this embodiment, for the surface reconstruction of S3, the 3D modeling software is one of SolidWorks, Preo or 3DMax.

[0083] In step two of this embodiment, for the model alignment of S1, the axis center line alignment can be selected, and the calculated value of the press-fitting amount when the distance between the large end face of the hub and the large end face of the shaft taper is at a temperature of 15°C is used as the relative position of the two models.

[0084] Alternatively, the alignment function of the software can be used to achieve precise circumferential alignment of the models by selecting common feature points or surfaces.

[0085] It should be noted that in this article, relational terms such as first and second are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any actual relationship or order between these entities or operations. Moreover, the term "comprising", "including" or any other variant thereof is intended to cover non-exclusive inclusion, so that a process, method, article or device comprising a series of elements not only includes those elements, but also includes other elements not expressly listed, or also includes elements inherent to such process, method, article or device.

[0086] Although the embodiments of the present invention have been shown and described, for those of ordinary skill in the art, it can be understood that various changes, modifications, substitutions and variations can be made to these embodiments without departing from the principles and spirit of the present invention. The scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A method to replace the traditional blue oil blending of propeller shafts, characterized in that: The following steps are involved: Step 1: 3D scanning and surface reconstruction S1. Select 3D scanner: Choose a suitable 3D scanner based on the size of the propeller and the limitations of the scanning environment; S2. Perform 3D scanning: Use a 3D scanner to scan the inner hole of the hub and the tapered end of the shaft, ensuring that the surface of the object is clean, unobstructed, and as still as possible during the scanning process; S3, surface reconstruction: Import the scanned 3D data into professional 3D modeling software, and use the surface reconstruction function in the software to generate a 3D surface model of the object based on the point cloud data; Step 2: Contact Analysis S1. Model alignment: Import the 3D surface models of the hub inner hole and the shaft tapered end into the same coordinate system to ensure that their axial positions are consistent with the actual situation; S2. Contact surface detection: Use the software's Boolean operations or collision detection functions to simulate the contact between two surfaces, and observe the contact surface, contact point, and possible interference area between them by slightly adjusting the relative positions of the objects; S3. Contact force analysis: Although 3D scanning technology itself cannot directly measure contact force, it can indirectly evaluate the size and direction of contact force by analyzing the shape, size and position of the contact surface, combined with factors such as the material and weight of the object or the pressure at the starting point. Finite element analysis software can also be used to simulate the contact and force conditions between objects to obtain more accurate analysis results. S4. Result output and report: Output the analysis results in the form of 3D models, 2D drawings or reports for subsequent grinding or maintenance work; The report can describe in detail the position, size, shape and possible interference or wear of the contact surface, and provide corresponding improvement suggestions.

2. A method for replacing the traditional blue oil blending of propeller shafts according to claim 1, characterized in that: In the step 1, S1 selects a 3D scanner. For medium and large propeller surfaces, a handheld laser 3D scanner can be selected.

3. A method for replacing the traditional blue oil blending of propeller shafts according to claim 1, characterized in that: In the step 1, S2 performs 3D scanning. According to the shape and size of the object, multiple scans need to be performed from different angles to obtain complete three-dimensional data.

4. A method for replacing the traditional blue oil blending of propeller shafts according to claim 1, characterized in that: In the step 1, the surface of S3 is reconstructed, and the 3D modeling software is one of SolidWorks, Preo or 3DMax.

5. The method for replacing the traditional blue oil blending of propeller shafts according to claim 1, characterized in that: In the step 2, the model alignment of S1 can be selected by aligning the shaft centerline, and the calculated value of the indentation amount when the temperature of the large end face of the hub is 15°C from the large end face of the shaft taper is taken as the relative position of the two models; You can also use the alignment function of the software to achieve precise alignment of the model in the circumferential direction by selecting common feature points or faces.

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