Runner body jig frame design method

Abstract

The invention provides a method for designing a runner body jig frame, which comprises the following steps of: functionally dividing a runner body into a lower half part fused with a main ship body and an independent closed upper half cylinder part in the head-tail direction and the up-down direction on the basis of curvature change and space closure of the runner body; the lower half part and the corresponding part of the main hull are used as a whole, and a first jig frame is manufactured in a positive manufacturing mode; for the independent upper half cylinder part, a second jig frame is manufactured in a single beveling reverse manufacturing mode with the direction of the longitudinal center line of the flow channel as a rotation and projection base plane, so that the projection line of the tail closed area of the upper half cylinder part is perpendicular to the base plane; and after the construction of the lower half part and the upper half cylinder part is completed respectively, the upper half cylinder part is removed from the second jig frame and is hoisted to the lower half part on the first jig frame to be accurately folded, and welding is completed. According to the technical scheme, the shape maintaining problem of a complex curved surface, the accurate positioning problem of a flow channel body and the safety construction problem in a narrow closed space can be solved at the same time.

Description

TECHNICAL FIELD

[0001] The present application belongs to the technical field of shipbuilding process, and particularly relates to a flow channel body jig design method. BACKGROUND

[0002] The hull jig is a key equipment in shipbuilding process, and is indispensable to the whole shipbuilding process. The core significance of the hull jig is to ensure the accuracy of the hull line type and size. Reasonable jig design is very meaningful to the construction of the hull.

[0003] In a ship with a water jet propulsion device, the flow channel body is a key component with extremely high manufacturing difficulty. The flow channel body is connected with the main hull below, and is connected with the propulsion cylinder of the tail part at the water outlet, forming a curved surface structure with extremely complex spatial relationship. The flow channel curved surface has small longitudinal and transverse bending radius, a large number of tangent lines and angle lines for controlling the outer shape of the curved surface, and a complex trend, and the tail part usually presents a closed area. The complex geometric characteristics make it extremely difficult to control the line type accuracy of this part. In the traditional construction method, the accuracy often exceeds the tolerance.

[0004] The hull jig is a core equipment for ensuring the accuracy of the hull line type and size in shipbuilding. Traditionally, for such a complex structure, the whole positive construction or the whole reverse construction method is usually adopted. However, when the whole positive construction is adopted, the closed area of the flow channel tail part forms a construction dead zone, which is difficult for personnel and equipment to enter, resulting in difficulties in assembly, welding and inspection, and the accuracy cannot be guaranteed. If the whole reverse construction is adopted, the connection area between the flow channel and the main hull becomes complex, and the structure of the jig itself will interfere with the subsequent closing operation.

[0005] Therefore, how to provide a flow channel body jig design method which can solve the problems of complex curved surface shape preservation, accurate positioning of the flow channel body, and safe construction in a narrow and closed space at the same time has become a technical problem to be solved. SUMMARY

[0006] The embodiment of the present application provides a flow channel body jig design method which can solve the problems of complex curved surface shape preservation, accurate positioning of the flow channel body, and safe construction in a narrow and closed space at the same time.

[0007] In the embodiment of the present application, a flow channel body jig design method is provided, which comprises the following steps:

[0008] S101, line type segmentation: analyzing the overall spatial line type of the flow channel body, based on the curvature change and spatial closure, functionally segmenting the flow channel body in the head-tail direction and the up-down direction, and dividing it into a lower half part fused with the main hull and an independent upper half cylindrical part in a closed shape; wherein the segmentation seam in the head-tail direction is arranged at the transition area where the main hull line type starts to gradually rise to the flow channel part;

[0009] S102, Lower half construction jig: The lower half and the corresponding part of the main hull are treated as a whole, and the first jig is made using the construction method. The shape of the first jig is constructed based on the baseline shape of the main hull.

[0010] S103, Upper half reverse frame: For the independent upper cylindrical part, a second frame is made by using a single oblique cut reverse method with the longitudinal center line of the flow channel as the rotation and projection base plane, so that the projection line of the closed area at the tail of the upper cylindrical part is perpendicular to the base plane.

[0011] S104. Closing: After the lower half and upper cylindrical part are constructed on the first and second jigs respectively, the upper cylindrical part is removed from the second jig and hoisted to the lower half on the first jig for precise closure and welding.

[0012] Furthermore, regarding the hull line segmentation, the selection of the fore-and-aft direction segmentation seam ensures that the rise height of the main hull line at that location is controlled within the range of 250mm to 350mm; the vertical segmentation is strictly performed along the arc of the upper cylindrical portion and the geometric tangent of the lower flow channel.

[0013] Furthermore, for the lower half of the precast jig, in the lower half precast jig step, the construction of the first jig satisfies the following: the jig working surface, i.e. the lowest point of the theoretical line of the outer plate, is set at a height of 800mm to 1000mm above the ground to reserve sufficient operating space; the arrangement of the jig template is determined according to the position of the main hull structure skeleton, with the transverse template corresponding to the rib plate position and the longitudinal template corresponding to the center keel and side keel positions.

[0014] Furthermore, the width of the template of the first jig is designed to be 200mm to 300mm, and its thickness δ satisfies the relationship: δ≥t+2mm, where t is the nominal thickness of the outer plate of the supported part.

[0015] Furthermore, for the upper part of the reverse-engineering frame, the template arrangement of the second frame is as follows: the end templates are set at the inner position 50mm to 100mm away from the beginning and end lines of the flow channel, and the spacing of the templates in the remaining middle parts is controlled between 400mm and 600mm according to the curvature of the flow channel to ensure effective support for complex curved surfaces.

[0016] Furthermore, for the upper part of the reverse-engineered frame, for the closed area at the tail of the upper cylindrical part, the corresponding frame template of the second frame is constructed as a closed ring support structure; the ring support structure is composed of a lower fixed template and an upper detachable template combined by connectors, and the upper detachable template can be disassembled before the closing step to facilitate the removal and hoisting of the upper cylindrical part.

[0017] Furthermore, the lower fixed template and the upper detachable template are connected by M16 or larger high-strength bolts, and positioning pins or matching tongue and groove structures are provided on the mating surface to ensure docking accuracy and overall rigidity.

[0018] Furthermore, for the upper part of the reverse-engineering frame, the working surface of the second frame is also set at a height of 800mm to 1000mm from the ground; the width of its frame template is 200 to 300mm, and the thickness δ satisfies the relationship: δ≥t+2mm, where t is the nominal thickness of the outer plate of the upper cylindrical part.

[0019] Furthermore, the chassis of the first and / or second jigs is a rigid welded frame made of steel profiles, including channel steel, I-beams, or H-beams. The natural frequency of the rigid welded frame is designed to be far from the main excitation frequency during construction to avoid resonance.

[0020] Furthermore, for the upper part of the reverse-engineered frame, CNC scribing or laser projection technology is used to accurately mark the waterline, centerline, and merging line of the flow channel on the frame template of the second frame, as a benchmark for construction and inspection.

[0021] The beneficial effects of this invention are as follows:

[0022] As can be seen from the above scheme, the embodiments of the present invention provide a flow channel jig design method. The method analyzes the overall spatial profile of the flow channel, and based on its curvature variation and spatial enclosure, functionally divides the flow channel in the bow-stern and vertical directions, into a lower half integrated with the main hull and an independent, enclosed upper cylindrical part. The lower half and the corresponding part of the main hull are treated as a whole, and a first jig is fabricated using a forward-casting method. The surface of the first jig is constructed based on the baseline profile of the main hull. For the independent upper cylindrical part, a second jig is fabricated using a single oblique-cut reverse-casting method with the longitudinal centerline of the flow channel as the rotation and projection base plane, so that the projection line of the closed area at the stern of the upper cylindrical part is perpendicular to the base plane. After the lower half and upper cylindrical part are constructed on the first and second jigs respectively, the upper cylindrical part is removed from the second jig, hoisted onto the lower half on the first jig for precise assembly and welding. The technical solution of this invention can simultaneously solve the problems of maintaining the shape of complex curved surfaces, accurately positioning the flow channel, and ensuring safe construction in a confined space. Attached Figure Description

[0023] Figure 1 This is a flowchart of a flow channel frame design method according to an embodiment of the present invention. Detailed Implementation

[0024] To make the objectives, technical solutions, and advantages of this invention clearer, the technical solutions of the embodiments of this invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of this invention. Based on the embodiments of this invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this invention.

[0025] like Figure 1 As shown, Figure 1 This is a schematic diagram of a flow channel frame design method according to an embodiment of the present invention.

[0026] Figure 1 A method for designing a flow channel frame includes:

[0027] S101. Linear Segmentation: Analyze the overall spatial linearity of the flow channel body. Based on its curvature variation and spatial enclosure, the flow channel body is functionally segmented in the bow-stern direction and the vertical direction, dividing it into a lower half that is integrated with the main hull and an independent, enclosed upper cylindrical part; wherein, the dividing seam in the bow-stern direction is set in the transition area where the main hull line gradually rises towards the flow channel part.

[0028] S102, Lower half construction jig: The lower half and the corresponding part of the main hull are treated as a whole, and the first jig is made using the construction method. The shape of the first jig is constructed based on the baseline shape of the main hull.

[0029] S103, Upper half reverse frame: For the independent upper cylindrical part, a second frame is made by using a single oblique cut reverse method with the longitudinal center line of the flow channel as the rotation and projection base plane, so that the projection line of the closed area at the tail of the upper cylindrical part is perpendicular to the base plane.

[0030] S104. Closing: After the lower half and upper cylindrical part are constructed on the first and second jigs respectively, the upper cylindrical part is removed from the second jig and hoisted to the lower half on the first jig for precise closure and welding.

[0031] In this invention, a flow channel jig design method breaks away from the traditional thinking of integral manufacturing, creatively dividing the flow channel into upper and lower parts according to "function" and "geometric characteristics". The lower part is constructed in the same direction as the main hull, ensuring continuity with the main structure and positioning reference; the upper cylindrical part adopts a single oblique cut reverse construction, cleverly transforming the most complex closed curved surface into an open posture that is easy to construct. This "lower forward, upper reverse" combination process is the first of its kind in the field, effectively solving the contradiction that a single construction method cannot take all the problems into account. Through reasonable template layout (such as corresponding frame position), strict template specifications (thickness and width), high-rigidity chassis design (including anti-resonance considerations), and the use of detachable ring templates that can be precisely positioned in key closed areas, a comprehensive precision control system is constructed. The use of CNC scribing or laser projection on the jig template further introduces digital precision control into the traditional process, ensuring the high fidelity of the complex curved surface of the flow channel.

[0032] This invention's technical solution completes the most difficult-to-construct enclosed areas on a reverse-engineered formwork, placing them in the optimal welding position (flat welding, horizontal welding), greatly improving construction conditions and ensuring personnel safety and welding quality. The detachable ring-shaped template design is an ingenious solution to the problem of removing enclosed components from the formwork, achieving both easy construction and removal, ensuring a smooth construction process. This method is clear in its approach and steps, using standard shipbuilding materials and processes, requiring no investment in special or expensive equipment. It is easy to promote and apply in shipbuilding enterprises, effectively reducing rework rates, improving production efficiency, and yielding significant economic benefits.

[0033] In another embodiment of the present invention, for the hull line segmentation, the selection of the aft and stern direction segmentation seams ensures that the rise height of the main hull line at that location is controlled within the range of 250mm to 350mm; the vertical segmentation is strictly performed along the arc of the upper cylindrical portion and the geometric tangent of the lower flow channel.

[0034] In another embodiment of the present invention, in the lower half of the precast jig, the construction of the first jig satisfies the following: the working surface of the jig, i.e. the lowest point of the theoretical line of the outer plate, is set at a height of 800mm to 1000mm above the ground to reserve sufficient operating space; the arrangement of the jig templates is determined according to the position of the main hull structure skeleton, with the transverse templates corresponding to the rib positions and the longitudinal templates corresponding to the positions of the center keel and the side keels.

[0035] In another embodiment of the present invention, the width of the template of the first jig is designed to be 200mm to 300mm, and its thickness δ satisfies the relationship: δ≥t+2mm, where t is the nominal thickness of the outer plate of the supported part.

[0036] In another embodiment of the present invention, for the upper part of the reverse-engineering frame, the template arrangement of the second frame is as follows: the end template is set at the inner side position 50mm to 100mm away from the beginning and end lines of the flow channel, and the spacing of the templates in the remaining middle parts is controlled between 400mm and 600mm according to the curvature of the flow channel to ensure effective support for complex curved surfaces.

[0037] In another embodiment of the present invention, for the upper part of the reverse-engineered frame, for the closed area at the tail of the upper cylindrical part, the corresponding frame template of the second frame is constructed as a closed annular support structure; the annular support structure is composed of a lower fixed template and an upper detachable template combined by connectors, and the upper detachable template can be disassembled before the closing step to facilitate the removal and hoisting of the upper cylindrical part.

[0038] In another embodiment of the present invention, the lower fixed template and the upper detachable template are connected by M16 or larger high-strength bolts, and a positioning pin or a matching tongue and groove structure is provided on the mating surface to ensure docking accuracy and overall rigidity.

[0039] In another embodiment of the present invention, for the upper part of the reverse-engineering frame, the working surface of the second frame is also set at a height of 800mm to 1000mm from the ground; the width of its frame template is 200 to 300mm, and the thickness δ satisfies the relationship: δ≥t+2mm, where t is the nominal thickness of the outer plate of the upper cylindrical part.

[0040] In another embodiment of the present invention, the chassis of the first jig and / or the second jig is a rigid welded frame made of steel profiles, including channel steel, I-beams or H-beams. The natural frequency of the rigid welded frame is designed to be far away from the main excitation frequency during construction to avoid resonance.

[0041] In another embodiment of the present invention, for the upper part of the reverse-engineered frame, the water line, center line and closure line of the flow channel are accurately marked on the frame template of the second frame using CNC scribing or laser projection technology, as a benchmark for construction and inspection.

[0042] In this embodiment of the invention, a method for designing a flow channel jig first involves dividing the flow channel body into sections. The three-dimensional model of the flow channel body is analyzed in a computer-aided design system to locate the transition point A where the main hull line begins to rise towards the flow channel. A dividing slit is then set at this point along the transverse direction, with a rise height H of approximately 300mm (falling within the range of 250-350mm). Simultaneously, the flow channel body is divided vertically along the geometric tangent B between the upper cylindrical section and the lower cylindrical section. Thus, the flow channel body is divided into a lower section (integrated with the main hull) and an upper cylindrical section.

[0043] Fabrication of the lower half of the hull formwork is commenced. A robust formwork chassis is formed by welding channel steel, with its height ensuring the working surface (theoretical line of the outer plating) is approximately 900mm above the ground. Transverse and longitudinal formwork templates are installed based on the positions of the main hull's ribs and longitudinal beams (such as the center keel and side keels). The templates are made of 22mm thick steel plates (assuming an outer plating thickness of t = 20mm, satisfying δ ≥ t + 2mm) and 250mm wide. All template profiles are precisely machined according to the hull form value table.

[0044] The upper cylindrical section of the molded frame is fabricated. A single-beveled base surface is established using the longitudinal centerline of the flow channel as a reference. The mold base is also constructed from channel steel welded into a rigid frame. End templates are installed approximately 80mm from the beginning and end lines of the flow channel, with the spacing L between the intermediate templates approximately 500mm (adjusted according to curvature). In the closed area at the tail, the mold template is designed as a ring. This ring template consists of a lower fixed template and an upper detachable template. Grooves are milled into the mating surfaces of both for initial positioning, and then four M16 high-strength bolts are used for fastening to ensure overall rigidity. On all mold templates, the waterline, centerline, and alignment line are marked using a CNC machine tool.

[0045] During construction, the two jigs can be worked on in parallel. The lower half is assembled and welded to the main hull structure on the first jig. The upper cylindrical part is assembled and welded on the second jig using a reverse-engineering method, with its stern closed area becoming an open "upward" state due to the reverse engineering, facilitating construction. After completion, the M16 bolts are loosened and removed, and the upper half of the annular template is removed, allowing the manufactured upper cylindrical part to be easily lifted off the second jig. Finally, the upper cylindrical part is hoisted above the lower half, which is already on the first jig, and precisely positioned according to the pre-marked alignment lines on the jig. Then, the circumferential weld between the upper and lower parts is completed, forming a complete flow channel.

[0046] This invention provides a method for designing a flow channel jig, which divides the flow channel into two parts for separate fabrication. The lower, rounded portion is integrated with the main hull and constructed in a forward manner, while the upper portion is constructed using a longitudinal single-oblique cut. This invention, through the rational division of the flow channel into upper and lower parts for separate jig fabrication, simultaneously solves the problems of maintaining the shape of complex curved surfaces, precise flow channel positioning, and safe construction in confined spaces.

[0047] This invention provides a method for designing a flow channel jig. The method analyzes the overall spatial profile of the flow channel and, based on its curvature variation and spatial enclosure, functionally divides the flow channel in both the bow-stern and vertical directions, into a lower half integrated with the main hull and an independent, enclosed upper cylindrical section. The lower half and its corresponding portion of the main hull are treated as a single unit, and a first jig is fabricated using a forward-casting method. The surface of this first jig is constructed based on the baseline profile of the main hull. For the independent upper cylindrical section, a second jig is fabricated using a single-oblique-cut reverse-casting method with the longitudinal centerline of the flow channel as the rotation and projection datum plane, ensuring that the projection line of the enclosed stern region of the upper cylindrical section is perpendicular to the datum plane. After the lower half and upper cylindrical section are constructed on the first and second jigs respectively, the upper cylindrical section is removed from the second jig, hoisted onto the first jig, and precisely joined and welded to the lower half.

[0048] The technical solution of this invention can simultaneously solve the problems of maintaining the shape of complex curved surfaces, accurately positioning the flow channel, and ensuring safe construction in a confined space.

[0049] The above are preferred embodiments of the present invention. It should be noted that, for those skilled in the art, several improvements and modifications can be made without departing from the principle of the present invention, and these improvements and modifications should also be considered within the scope of protection of the present invention.

Claims

1. A method of designing a flow channel body jig, characterized by, The method comprises: S101, dividing the lines: analyzing the overall spatial line type of the flow passage body, based on the curvature change and the spatial closure, functionally dividing the flow passage body in the head-tail direction and the up-down direction, and dividing into a lower half part fused with the main hull and an independent, closed upper half cylindrical part; wherein the dividing seam in the head-tail direction is arranged at the transition area where the main hull line type gradually rises from the main hull line type to the flow passage part; S102, lower half part positive building jig: taking the lower half part and the corresponding part of the main hull as a whole, using the positive building method to manufacture a first jig, and the profile of the first jig is constructed based on the reference line type of the main hull; S103, upper half part reverse building jig: for the independent upper half cylindrical part, using the single oblique cutting reverse building method with the flow passage longitudinal center line direction as the rotation and projection base surface to manufacture a second jig, so that the projection line of the tail closed area of the upper half cylindrical part is perpendicular to the base surface; S104, folding: after completing the construction of the lower half part and the upper half cylindrical part on the first jig and the second jig respectively, the upper half cylindrical part is detached from the second jig, hoisted to the lower half part on the first jig for accurate folding and welding.

2. The method of designing a flow channel body jig according to claim 1, wherein For line division, the selection of the head-tail direction dividing seam controls the rising height of the main hull line type at this part within the range of 250mm to 350mm; the up-down direction division is strictly along the geometric tangent of the circular arc of the upper half cylindrical part and the lower half part flow passage.

3. The method of designing a flow channel body jig according to claim 1, wherein For the lower half part positive building jig, in the lower half part positive building jig step, the construction of the first jig satisfies: the jig working surface, i.e. the lowest point of the theoretical line of the outer plate, is set at a height of 800mm to 1000mm from the ground to reserve sufficient operation space; the arrangement of the jig templates is determined according to the position of the main hull structure skeleton, the transverse templates correspond to the position of the rib plates, and the longitudinal templates correspond to the position of the center keel and the side keel.

4. The method of designing a flow channel body jig according to claim 3, wherein The width of the jig template of the first jig is designed to be 200mm to 300mm, and the thickness δ satisfies the relationship: δ≥t+2mm, where t is the nominal thickness of the outer plate at the supported part.

5. The method of designing a flow channel body jig according to claim 1, wherein For the upper half part reverse building jig, the template arrangement of the second jig is: end templates are arranged at the inner side position 50mm to 100mm away from the head-tail end line of the flow passage, and the spacing of the templates at the remaining intermediate positions is controlled within the range of 400mm to 600mm according to the flow passage curvature, so as to ensure effective support for the complex curved surface.

6. The method of designing a flow channel body jig according to claim 1 or 5, wherein For the upper half part reverse building jig, for the tail closed area of the upper half cylindrical part, the corresponding jig template of the second jig is constructed as a closed ring support structure; the ring support structure is composed of a lower fixed template and an upper detachable template through a connecting piece, and the upper detachable template can be detached before the folding step, so as to facilitate the detachment and hoisting of the upper half cylindrical part.

7. The method of designing a flow channel body jig according to claim 6, wherein M16 or larger high-strength bolts are used to connect the lower fixed template and the upper detachable template, and positioning pins or matching concave-convex groove structures are arranged at the joint surface to ensure the accuracy of the joint and the overall rigidity.

8. The method of designing a flow channel body jig according to claim 1, wherein For the upper half of the reverse building tire frame, the working surface of the second tire frame is also set at a height of 800mm to 1000mm from the ground; The width of the tire frame template is 200-300mm, and the thickness δ satisfies the relationship: δ ≥ t + 2mm, wherein t is the nominal thickness of the outer plate of the upper half cylindrical portion.

9. The method of designing a flow channel body jig according to claim 1, wherein The chassis of the first tire frame and / or the second tire frame is a rigid welded frame welded by section steel, including channel steel, I-beam or H-beam, and the natural frequency of the rigid welded frame is designed to be far away from the main excitation frequency in the construction process to avoid resonance.

10. The method of designing a flow channel body jig according to claim 1, wherein For the upper half of the reverse building tire frame, the waterline, centerline and closing line of the runner are accurately plotted on the tire frame template of the second tire frame by using numerical control marking or laser projection technology as the basis for construction and inspection.

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