A method of determining a flow guide device margin

Abstract

The method for determining the excess amount of the flow guiding device comprises the following steps: S1, marking four reference points of the flow guiding fin on the outer contour lines at both ends of the stern cast steel part; S2, surveying the bow and stern mounting center line; S3, marking the bow and stern connecting points corresponding to the flow guiding fin on the bow and stern mounting center line; S4, drawing the connecting contour line on the stern cast steel part; S5, marking a plurality of auxiliary connecting points on each connecting contour line, and marking the corresponding contour mark points on the inner end outer contour line of the corresponding flow guiding fin in the flow guiding device; S6, assembling the stern section, and measuring the coordinates of the stern end inner vertex of the stern cast steel part and the connecting points of the stern cast steel part in the first coordinate system; S7, calculating the coordinates of the two precision control points in the first coordinate system when the flow guiding device is theoretically installed; S8, measuring the coordinates of the contour mark points and the two precision control points on the flow guiding device in the second coordinate system; and S9, coordinate system fitting, to obtain the excess amount. The present application is convenient for the installation of the flow guiding device without excess amount.

Description

TECHNICAL FIELD

[0001] The present application belongs to the technical field of shipbuilding, and particularly relates to a method for determining the excess amount of a flow guiding device. BACKGROUND

[0002] The stern cast steel part is a purchased product, which is formed by pouring. Since the stern purchased part obtained by pouring is prone to burrs, flash and other defects, the external line type of the stern cast steel part of the same specification will also differ. In order to avoid the problem that the flow guiding device cannot be installed, the flow guiding device manufacturer will increase a certain excess amount (usually 100mm-150mm) at the end of each flow guiding fin when manufacturing the flow guiding device. When the flow guiding device is installed, the excess amount is cut to ensure the smooth installation of the flow guiding device.

[0003] At present, when the flow guiding device is installed, a rough initial excess amount value is obtained according to past work experience, the flow guiding device after cutting the initial excess amount value is hoisted to the stern cast steel part of the stern section for positioning, and the excess amount is gradually cut according to the actual deviation during installation and positioning, until the flow guiding device is positioned to the accurate position. It needs a long time for positioning and cutting, which greatly affects the installation efficiency of the flow guiding device. SUMMARY

[0004] In view of the above shortcomings of the prior art, the purpose of the present application is to provide a method for determining the excess amount of a flow guiding device, which can determine the excess amount of each flow guiding fin before the flow guiding device is hoisted, lay a foundation for the subsequent installation of the flow guiding device without excess amount, and effectively improve the installation efficiency of the flow guiding device.

[0005] To achieve the above-mentioned purpose and other related purposes, the present application provides a method for determining the excess amount of a flow guiding device, the flow guiding device comprising a fan-shaped flow guiding cover and first and second flow guiding fins located on the flow guiding cover; the first flow guiding fins are three, and the three first flow guiding fins are distributed at equal angles with the center of the flow guiding cover as the center; the first flow guiding fins comprise outer fins and inner fins, and the second flow guiding fins are inner fins; the excess amount determination method comprises:

[0006] S1. According to the installation requirements of the flow guiding device, the positions of four inner vertices on the inner contour line of the stern end face of the stern cast steel part and the positions of four inner vertices on the inner contour line of the bow end face of the stern cast steel part, marking 4 flow guiding fin stern reference points on the outer contour line of the stern end face of the stern cast steel part, and marking 4 flow guiding fin bow reference points on the outer contour line of the bow end face of the stern cast steel part;

[0007] S2. Plotting 4 bow-stern installation center lines of the flow guiding fins on the side surface of the stern cast steel part;

[0008] S3, according to the installation requirements of the flow guiding device, the length of each flow guiding fin in the bow-stern direction, and the distance between the stern end face of each flow guiding fin and the stern end face of the flow cover, mark the bow connection point and the stern connection point of the corresponding flow guiding fin on the four bow-stern installation center lines;

[0009] S4, according to the end face of the connection end of each flow guiding fin, make a paper template corresponding to the flow guiding fin; paste each paper template on the outer side of the stern cast steel part, so that the bow top point and the stern top point of the paper template coincide with the bow connection point and the stern connection point on the bow-stern installation center line of the corresponding flow guiding fin respectively, so as to draw the outer contour line of each paper template on the outer side of the stern cast steel part as the connection contour line of each flow guiding fin;

[0010] S5, mark a plurality of auxiliary connection points on the connection contour line of each flow guiding fin, and mark a contour mark point corresponding to each connection point on the inner end outer contour line of the corresponding flow guiding fin in the flow guiding device;

[0011] S6, assemble the stern cast steel part with the rest of the stern section to obtain the stern section; then, use the total station to obtain the three-dimensional coordinates of each connection point on the stern cast steel part and the four inner top points of the stern end face of the stern cast steel part in the first coordinate system;

[0012] S7, according to the three-dimensional coordinate values of the four inner top points of the stern end face of the stern cast steel part in the first coordinate system and the installation requirements of the flow guiding device, determine the three-dimensional coordinate values of the two precision control points on the flow guiding device in the first coordinate system when the flow guiding device is installed on the stern cast steel part;

[0013] S8, place the flow guiding device on the ground, and use the total station to measure each contour mark point and the two precision control points on the flow guiding device to obtain the three-dimensional coordinates of each measurement point on the flow guiding device in the second coordinate system;

[0014] S9, fit the first coordinate system and the second coordinate system with the two precision control points as the reference, and take the distance between each contour mark point and the corresponding connection point in the same coordinate system as the excess to be trimmed.

[0015] Preferably, the method for determining the plurality of auxiliary connection points on each connection contour line is: marking a plurality of equal division points at equal intervals between the bow connection point and the stern connection point of each bow-stern installation center line, and drawing a bisector line with each equal division point as the base point, so that each bisector line intersects the corresponding connection contour line to determine the position of each auxiliary connection point on the connection contour line.

[0016] Preferably, in the step S9, the fitting of the two coordinate systems is carried out in the Eco BLOCK software.

[0017] Preferably, the first coordinate system is a ship body coordinate system, so as to reduce the calculation difficulty of the precision control points.

[0018] As described above, the method for determining the excess amount of the flow guiding device has the following beneficial effects:

[0019] The connecting contour lines of the connecting ends of the flow guiding fins on the stern cast steel piece are marked by using the paper template of the connecting ends of the flow guiding fins, and a plurality of connecting points are marked on the connecting contour lines; then, the contour marking points corresponding to the connecting points on the connecting contour lines are marked on the outer contour lines of the connecting ends of the flow guiding fins; then, the three-dimensional coordinate values of the connecting points of the stern cast steel piece on the stern section and the apexes on the inner contour line of the stern end surface of the stern cast steel piece in the first coordinate system are measured by using the total station instrument, and the three-dimensional coordinate values of the two precision control points on the flow guiding device in the first coordinate system when the flow guiding device is installed on the stern section are obtained; then, the three-dimensional coordinate values of the contour marking points and the two precision control points on the flow guiding device in the second coordinate system are measured by using the total station instrument; finally, the two coordinate systems are fitted by taking the two precision control points as the reference, and the distance between the connecting points and the corresponding contour marking points in the same coordinate system is taken as the excess amount at different contour marking points, so that the excess amount is trimmed before the installation of the flow guiding device, and the foundation for the installation of the flow guiding device without excess amount is laid, and the installation efficiency of the flow guiding device is effectively improved. BRIEF DESCRIPTION OF DRAWINGS

[0020] Figure 1 It is a side view of the installation process of the flow guiding device.

[0021] Figure 2 It is a stern view of the installation process of the flow guiding device,

[0022] Figure 3 It is a schematic view of determining the reference points of the flow guiding fins on the stern cast steel piece before the assembly of the stern section.

[0023] Figure 4 It is a schematic view of determining the bow and stern connecting points of the flow guiding fins on the stern cast steel piece before the assembly of the stern section.

[0024] Figure 5 It is a schematic view of determining the auxiliary connecting points on the connecting contour lines of the flow guiding fins.

[0025] Figure 6 It is a schematic view of obtaining the coordinates of the measuring points of the stern cast steel piece on the stern section by using the total station instrument,

[0026] Figure 7 It is a schematic view of the positions of the precision control points on the flow guiding device.

[0027] Figure 8 It is a schematic view of measuring the precision control points on the flow guiding device and the contour marking points on the connecting ends of the flow guiding fins by using the total station instrument.

[0028] Reference Signs List

[0029] stern centerline 01, bossing centerline 02, bossing 11, first bossing fin 12a, second bossing fin 12b, stern casting 2, stern end horizontal centerline 21a, stern end vertical centerline 21b, stern end horizontal positioning line 21c, bow end horizontal centerline 22a, bow end vertical centerline 22b, bow end horizontal positioning line 22c, bow-stern mounting centerline 3. DETAILED DESCRIPTION

[0030] The following describes embodiments of the present application by specific examples, and those skilled in the art can easily understand other advantages and effects of the present application from the content disclosed in the specification.

[0031] Please refer to Figures 1 to 8 . It should be understood that the structures, proportions, sizes, etc. shown in the drawings attached to the specification are only used to illustrate the content disclosed in the specification for those skilled in the art to understand and read, and are not used to limit the defined conditions under which the present application can be implemented, so they do not have technical significance. Any modification of the structure, change of the proportional relationship, or adjustment of the size, without affecting the effects that can be produced by the present application and the purposes that can be achieved, should still fall within the scope of the technology disclosed by the present application. At the same time, the terms such as "upper", "lower", "left", "right", "middle" and "one" used in the specification are only for the convenience of clear description, and are not used to limit the scope in which the present application can be implemented, and the change or adjustment of the relative relationship, without substantially changing the technical content, is also considered as the scope in which the present application can be implemented.

[0032] The bossing device and the stern casting 2 involved in the present application are all purchased parts. As shown in Figure 2 , the bossing device includes a fan-shaped bossing 11 and first bossing fins 12a and second bossing fins 12b located on the bossing 11; wherein the first bossing fins 12a are three, the three first bossing fins 12a are distributed at an angle of 45° with the center of the bossing 11 as the center, and the included angle between the second bossing fin 12b and the vertical centerline of the bossing 11 is a fixed angle; the first bossing fin 12a includes an outer fin and an inner fin, and the second bossing fin 12b is an inner fin; each bossing fin is connected to the stern casting 2 through the inner fin; because the external contour changes when the stern casting 2 is cast, therefore, when manufacturing the bossing device, an excess of 80mm~150mm is added in advance, and then during installation, the excess is cut while positioning, until it is positioned to the accurate position, to ensure the stability of the subsequent connection of the bossing device, but this greatly increases the installation period, which is not conducive to the rapid construction of the ship.

[0033] Based on this, the embodiment provides a method for determining the allowance of a flow guiding device, which can determine the allowance before the installation of the flow guiding device, so as to realize the installation of the flow guiding device without allowance and greatly improve the installation efficiency. The allowance determination method comprises the following steps:

[0034] S1. According to the installation requirements of the flow guiding device, the positions of the four inner vertexes on the inner contour line of the stern end face of the stern cast steel piece 2 and the positions of the four inner vertexes on the inner contour line of the bow end face of the stern cast steel piece 2, four stern reference points of the flow guiding fin on the outer contour line of the stern end face of the stern cast steel piece 2 are marked, and four bow reference points of the flow guiding fin on the outer contour line of the bow end face of the stern cast steel piece 2 are marked.

[0035] As shown in Figure 3 , the four inner vertexes A1-A4 on the inner contour line of the stern end face of the stern cast steel piece 2 and the four inner vertexes A1'-A4' on the inner contour line of the bow end face of the stern cast steel piece 2 are usually marked by the manufacturer to determine the stern cross center line (i.e. the stern horizontal center line 21a and the stern vertical center line 21b) of the stern end of the stern cast steel piece 2 and the bow cross center line (i.e. the bow horizontal center line 22a and the bow vertical center line 22b) of the stern cast steel piece 2. The intersection of the stern cross center line and the outer contour line of the stern end face of the stern cast steel piece 2 can determine the four outer vertexes B1-B4 on the outer contour line of the stern end face of the stern cast steel piece 2. The intersection of the bow cross center line and the outer contour line of the bow end face of the stern cast steel piece 2 can determine the four outer vertexes B1'-B4' on the outer contour line of the bow end face of the stern cast steel piece 2.

[0036] As can be seen from Figure 1 and Figure 2 , when the flow guiding device is installed on the stern cast steel piece 2, the distance between the center line 02 of the flow guiding cover and the stern shaft center line 01 is 100 mm. Based on this, the stern horizontal positioning line 21c which is 100 mm away from the stern horizontal center line 21a is drawn on the stern end face of the stern cast steel piece 2, and the bow horizontal positioning line 22c which is 100 mm away from the bow horizontal center line 22a is drawn on the bow end face of the stern cast steel piece 2 (as shown in Figure 3 ); the intersection of the stern horizontal positioning line 21c and the outer contour line of the stern end face of the stern cast steel piece 2 and the intersection of the bow horizontal positioning line 22c and the outer contour line of the bow end face of the stern cast steel piece 2 can determine the stern reference point C3 and the bow reference point C3' of the first flow guiding fin 12a installed horizontally.

[0037] According to Figure 1 and Figure 2The angle positions of the remaining two first flow guiding fins 12a and the second flow guiding fin 12b, in combination with the inner hole diameter of the stern cast steel piece 2 (known data, provided by the manufacturer) and the outer contour size of the two end faces of the stern cast steel piece 2 (known data, provided by the manufacturer), are used to calculate the theoretical distance between the stern reference point of each flow guiding fin and the horizontal positioning line 21c of the stern end and the theoretical distance between the bow reference point of each flow guiding fin and the horizontal positioning line 22c of the bow end, and then the stern reference points C1, C2, C4 of each flow guiding fin are marked on the outer contour line of the stern end face of the stern cast steel piece 2 according to the theoretical distance obtained by calculation, and the corresponding bow reference points C1', C2', C4' of each flow guiding fin are marked on the outer contour line of the bow end face of the stern cast steel piece 2 (as shown in Figure 3 ).

[0038] S2, the bow-stern installation center line 3 of the four flow guiding fins is drawn on the side surface of the stern cast steel piece 2.

[0039] As shown in Figure 4 , the bow-stern installation center line 3 of the corresponding flow guiding fin is drawn by connecting the bow reference point and the stern reference point of each flow guiding fin using the wire projection method.

[0040] The principle of the wire projection method is explained in detail by taking the drawing of the bow-stern installation center line 3 of the second flow guiding fin 12b as an example: that is, the stern reference point C1 and the bow reference point C1' are located in the upper position and in the same vertical plane by rotating the entire stern cast steel piece 2; then, the wire is contacted with the stern reference point C1 and the bow reference point C1' at both ends of the wire, at this time, the projection line of the wire on the outer side surface of the stern cast steel piece 2 is the bow-stern installation center line 3 of the second flow guiding fin 12b, and the drawing of the corresponding bow-stern installation center line 3 is completed.

[0041] S3, according to the installation requirements of the flow guiding device, the length of each flow guiding fin in the bow-stern direction, and the distance between the stern end face of each flow guiding fin and the stern end face of the flow guiding cover, the stern connecting point D1 and the bow connecting point D2 of the corresponding flow guiding fin are marked on the four bow-stern installation center lines.

[0042] As can be seen from Figure 1 and Figure 2 , the distance between the stern end face of the flow guiding cover 11 and the stern end face of the stern cast steel piece 2 is 118mm; the length of each flow guiding fin in the bow-stern direction and the distance between the stern end face of each flow guiding fin and the stern end face of the flow guiding cover can be directly measured on the energy-saving device; based on these data, it can be known that when each flow guiding fin is installed on the stern cast steel piece 2, the distance between the stern end face of each flow guiding fin and the stern end face of the stern cast steel piece 2 and the distance between the bow end face of each flow guiding fin and the stern end face of the stern cast steel piece 2, and then the stern connecting point D1 and the bow connecting point D2 of the corresponding flow guiding fin are marked on each bow-stern installation center line 3 on the stern cast steel piece 2.

[0043] S4, according to the connecting end face of each guide fin in the flow guiding device, a paper template corresponding to the guide fin is made; each paper template is attached to the outer side of the stern cast steel part 2, so that the bow top point and the stern top point of the paper template are respectively coincided with the bow connecting point D2 and the stern connecting point D1 on the bow-stern installation center line 3 of the corresponding guide fin, so as to draw the outer contour line of each paper template on the outer side of the stern cast steel part as the connecting contour line of each guide fin;

[0044] S5, a plurality of auxiliary connecting points are marked on the connecting contour line of each guide fin, and a contour mark point corresponding to each connecting point is marked on the connecting end outer contour line of the corresponding guide fin in the flow guiding device;

[0045] As shown in Figure 5 , a plurality of equal division points are marked at equal intervals between the stern connecting point D1 and the bow connecting point D2 of each bow-stern installation center line 3, and a bisector line (the bisector line is a curve, and the plane where the bisector line is required to be parallel to the stern end face of the stern cast steel part 2) is drawn with each equal division point as the base point, so that each bisector line intersects with the corresponding connecting contour line to determine the position of each auxiliary connecting point D3-D10 on the connecting contour line; the stern connecting point D1, the bow connecting point D2 and the auxiliary connecting points D3-D10 jointly constitute the ideal connecting point of the guide fin; then the bow contour mark point and the stern contour mark point are knocked on the connecting end outer contour line of each guide fin, and the same principle is used to mark the auxiliary contour mark point corresponding to the auxiliary connecting point on the connecting end outer contour line of each guide fin; the bow contour mark point, the stern contour mark point and each auxiliary contour mark point jointly constitute the actual contour point of the guide fin (not shown in the figure).

[0046] S6, the stern cast steel part and the remaining parts of the stern section are assembled together to obtain the stern section; then, the three-dimensional coordinates of each connecting point on the stern cast steel part and the four inner top points on the inner contour line of the stern end face of the stern cast steel part in the first coordinate system are measured by using a total station instrument;

[0047] As shown in Figure 6 , the three-dimensional coordinates of the four inner top points A1-A4 of the stern cast steel part 2 and the four groups of connecting points D1-D10 on the stern cast steel part in the first coordinate system are obtained by using the total station instrument; the first coordinate system is preferably selected as the ship body coordinate system, which is convenient for the theoretical installation coordinates of the subsequent precision control points J1-J2; as shown in Figure 7 , the precision control points J1 and J2 are the intersection points of the cross center line of the flow guide cover 11 on the stern end face of the guide fin and the inner diameter of the flow guide cover 11, which are marked by the manufacturer.

[0048] S7, according to the three-dimensional coordinate values of each measurement point on the stern cast steel part in the first coordinate system and the installation requirements of the flow guiding device, the three-dimensional coordinate values of the two precision control points on the flow guiding device in the first coordinate system when the flow guiding device is installed on the stern cast steel part are determined.

[0049] According to the inner vertex A1-A4 coordinates in the first coordinate system measured in the S7 step, the three-dimensional coordinates of the precision control points J1-J2 of the flow guiding device in the first coordinate system when the flow guiding device is installed on the stern cast steel piece 2 can be calculated. Figure 2 、 Figure 7

[0050] S8, as shown in Figure 8 , the flow guiding device is placed on the ground, and the total station is used to measure the profile mark points and the two precision control points on the flow guiding device, to obtain the three-dimensional coordinates of the measurement points on the flow guiding device in the second coordinate system;

[0051] S9, the first coordinate system and the second coordinate system are fitted with the two precision control points as the reference, and the distance between the profile mark points and the corresponding connecting points in the same coordinate system is taken as the allowance to be cut.

[0052] In order to reduce the fitting difficulty, the fitting process can be carried out in the Eco BLOCK software.

[0053] Since the present application uses the paper template of the connecting end of each flow guiding fin to mark the connecting profile line of each flow guiding fin installed on the side surface of the stern cast steel piece, to obtain the ideal connecting point of each flow guiding fin; then, the profile mark points corresponding to each ideal connecting point on the connecting profile line are marked on the outer profile line of the connecting end of each flow guiding fin of the flow guiding device; then, the three-dimensional coordinate values of the ideal connecting points of the stern cast steel piece on the stern section and the vertexes on the inner profile line of the stern end surface of the stern cast steel piece in the first coordinate system are measured by using the total station, and the three-dimensional coordinate values of the two precision control points of the flow guiding device in the first coordinate system when the flow guiding device is installed on the stern section are obtained; then, the three-dimensional coordinate values of the profile mark points and the two precision control points of the flow guiding device in the second coordinate system are measured by using the total station; finally, the two coordinate systems are fitted with the two precision control points as the reference, the distance between the connecting points and the corresponding profile mark points in the same coordinate system is taken as the allowance value at different profile mark points, which facilitates the allowance cutting before the installation of the flow guiding device, lays the foundation for the allowance-free installation of the flow guiding device, and effectively improves the installation efficiency of the flow guiding device.

[0054] The above embodiments only exemplarily illustrate the principles and effects of the present application, and are not used to limit the present application. Any person skilled in the art can modify or change the above embodiments without departing from the spirit and scope of the present application. Therefore, all equivalent modifications or changes completed by those skilled in the art without departing from the spirit and technical thought disclosed by the present application should be covered by the claims of the present application.​

Claims

1. A method for determining the remaining amount of a flow guiding device, the flow guiding device comprising a flow guiding cover in the shape of a sector and a first flow guiding fin and a second flow guiding fin located on the flow guiding cover; the first flow guiding fin has three, and the three first flow guiding fins are distributed at equal angles with the center of the flow guiding cover as the center; characterized in that, The excess determination method comprises: S1, according to the installation requirements of the flow guiding device, the positions of the four inner vertexes on the inner contour line of the stern end face of the stern cast steel piece and the positions of the four inner vertexes on the inner contour line of the bow end face of the stern cast steel piece, marking 4 stern reference points of the flow guiding fin on the outer contour line of the stern end face of the stern cast steel piece and marking 4 bow reference points of the flow guiding fin on the outer contour line of the bow end face of the stern cast steel piece; S2, marking 4 bow-stern installation center lines of the flow guiding fin on the side surface of the stern cast steel piece; S3, according to the installation requirements of the flow guiding device, the length of each flow guiding fin in the bow-stern direction of the flow guiding device, and the distance between the stern end face of each flow guiding fin and the stern end face of the flow guiding cover, marking the stern connecting point and the bow connecting point of the corresponding flow guiding fin on the 4 bow-stern installation center lines; S4, according to the inner end face of each flow guiding fin in the flow guiding device, making a paper template of the corresponding flow guiding fin; then, pasting each paper template on the outer side surface of the stern cast steel piece, so that the bow vertex and the stern vertex of the paper template are coincided with the bow connecting point and the stern connecting point on the bow-stern installation center line of the corresponding flow guiding fin respectively, so as to mark the outer contour line of each paper template on the outer side surface of the stern cast steel piece as the connecting contour line of each flow guiding fin; S5, marking a plurality of auxiliary connecting points on the connecting contour line of each flow guiding fin, and marking a contour mark point corresponding to each connecting point on the inner end outer contour line of the corresponding flow guiding fin in the flow guiding device; S6, assembling the stern cast steel piece and the remaining parts of the stern section together to obtain the stern section; then, using a total station instrument to obtain the three-dimensional coordinates of each connecting point on the stern cast steel piece and the four inner vertexes on the stern end face of the stern cast steel piece in the first coordinate system; S7, according to the three-dimensional coordinate values of the four inner vertexes on the stern end face of the stern cast steel piece in the first coordinate system and the installation requirements of the flow guiding device, determining the three-dimensional coordinate values of the two precision control points on the flow guiding device in the first coordinate system when the flow guiding device is installed on the stern cast steel piece; S8, laying the flow guiding device on the ground, and using a total station instrument to measure each contour mark point and the two precision control points on the flow guiding device to obtain the three-dimensional coordinates of each measurement point on the flow guiding device in the second coordinate system; S9, fitting the first coordinate system and the second coordinate system with the two precision control points as the reference, and taking the distance between each contour mark point and the corresponding connecting point in the same coordinate system as the excess to be trimmed.

2. A method of determining the amount of a flow guide device according to claim 1, wherein The determination method of the plurality of auxiliary connecting points on each connecting contour line is that: a plurality of equal division points are marked at equal intervals between the bow connecting point and the stern connecting point of each bow-stern installation center line, and each equal division line is drawn with each equal division point as the base point, so that each equal division line intersects with the corresponding connecting contour line to determine the positions of the auxiliary connecting points on the connecting contour line.

3. A method of determining the remaining amount of a flow guide according to claim 1 or 2, characterized in that In the step S9, the fitting of the two coordinate systems is performed in the Eco BLOCK software.

4. The method of claim 1, wherein The first coordinate system is a ship body coordinate system.

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