A forming die and forming method for a rotating cylinder sail outer cylinder

Abstract

The application provides a forming die and a forming method for an outer cylinder of a rotary cylinder sail, which comprises a die body and a locking mechanism arranged at the edge of the die body, the die body is arranged as a two-lobed die structure, the two-lobed die structure is respectively a fixed side die and a reversible side die, the cavity of the fixed side die and the cavity of the reversible side die are both semicylindrical, and the locking mechanism is arranged on the abutting surface of the fixed side die and the reversible side die. The application adopts a single-side reversible two-lobed die with a built-in heating function, synchronously forms and solidifies the two-lobed rotary cylinder shell through a vacuum pouring mode, and ensures the rigidity and uniform quality distribution of the shell body in the axial and circumferential directions. After the two-lobed shell is closed, a "inner adhesive tape+outer adhesive tape+shell body" cooperative structure design is adopted for the parting position, so that the parting position and the shell body form an integrated stress structure, the parting area and the main body area are ensured to have equal quality and rigidity, the process flow is simplified, and the production efficiency is improved.

Description

Technical Field

[0001] This invention relates to the field of rotary sail forming technology, and more specifically, to a forming mold and forming method for the outer cylinder of a rotary sail. Background Technology

[0002] As a core component of ship sails, the uniformity of the overall stiffness of the swivel directly affects its working efficiency, operational stability, and service life. During operation, the swivel must withstand complex loads. If the mass or stiffness distribution of different parts of the circumference is uneven, it can easily lead to a decrease in dynamic balance performance, local stress concentration, uneven deformation, and even structural damage.

[0003] In existing rotary forming processes, the mainstream method is multi-segment splicing forming. This process has the following shortcomings:

[0004] First, there are many seams, usually requiring three seams. The seams need to be reinforced with additional adhesive or by using bolts, rivets, etc. The process is complicated, requires a high degree of manual labor, has low production efficiency, and makes it difficult to control the quality of the seams.

[0005] Secondly, the bonding quality at the splicing seam is difficult to control precisely, and problems such as uneven resin distribution and weak bonding are likely to occur. This results in the stiffness of the splicing area being significantly lower than that of the main body of the rotating cylinder, forming a point of sudden change in stiffness. Long-term use may lead to cracking or failure.

[0006] Third, after the multi-lobed arc-shaped blanks are formed separately, it is difficult to ensure structural symmetry and dimensional consistency. After splicing, the overall roundness deviation of the cylinder is large and the stiffness distribution is uneven, which leads to structural deformation or even failure.

[0007] Fourth, after the splicing is completed, post-processing steps such as counterweighting, stress relief, and overall shaping are usually required, which further increases production costs and production cycle.

[0008] In addition to the multi-lobed process, the existing simple two-lobed splicing or winding molding processes also have problems such as insufficient stiffness at the parting position, complex process, low production efficiency and poor adaptability, making it difficult to meet the requirements of equal stiffness for rotary sails. Summary of the Invention

[0009] In view of this, the present invention aims to propose a two-part molding die and molding method for the outer cylinder of a rotary sail, so as to solve the problems existing in the prior art rotary sail molding process, such as many splicing seams, obvious stiffness abrupt change, complex process, low production efficiency, and difficulty in ensuring the stiffness at the parting position.

[0010] To achieve the above objectives, the technical solution of the present invention is implemented as follows:

[0011] A forming mold for the outer cylinder of a rotary sail includes a mold body and a locking mechanism disposed on the edge of the mold body. The mold body is configured as a two-part mold structure, and the two parts of the mold structure are connected as one piece. The two parts of the mold structure are a fixed side mold and a flip-up side mold. The cavities of the fixed side mold and the flip-up side mold are both semi-cylindrical. The locking mechanism is disposed on the mating surface of the fixed side mold and the flip-up side mold.

[0012] In some embodiments, multiple locking mechanisms are provided on each side edge of the mold body, and the multiple locking mechanisms are evenly distributed along the edge axis of the mold body.

[0013] In some embodiments, a heating device is provided inside the mold body.

[0014] In some embodiments, the heating device is configured as a heating band that extends along the length of the mold body, and there are multiple heating bands that are evenly arranged along an arc-shaped semicircle inside the mold body.

[0015] In some embodiments, a hydraulic flipping arm is provided between the fixed-side mold and the flippable-side mold, the hydraulic flipping arm being able to drive the flippable-side mold to flip and fold towards the fixed-side mold.

[0016] In some embodiments, the molding die further includes a mold flange, the mold flange being configured as an annular frame, and the edge of the mold flange being configured as a "Z" shaped structure.

[0017] The present invention also provides a method for forming the outer cylinder of a rotary sail, comprising:

[0018] Fiber-reinforced materials are laid on the inner walls of the cavities of the two mold halves;

[0019] Vacuum injection is performed on the two mold halves, and the built-in heating device is activated to simultaneously solidify the shell material inside the two mold halves, forming the main body of the rotary cylinder shell;

[0020] The flip-out side mold is flipped over and closed with the fixed side mold, and then locked by a locking structure.

[0021] Precast adhesive tape is laid at the parting point of the two shell materials, and an external hand lay-up process is used to form a synergistic stress-bearing structure of "precast adhesive tape + external hand lay-up + shell body";

[0022] A second heating and curing process is performed to ensure that the bonding area at the mold parting point is cured to the same degree as the main body of the shell.

[0023] In some embodiments, the fiber reinforcement material is a carbon fiber / glass fiber hybrid reinforced dry fiber, which is laid on the inner wall of the cavity in a cross-layout manner.

[0024] In some embodiments, during the pressure holding phase of the vacuum injection, the mold airtightness depressurization does not exceed 0.005 MPa within 10 minutes.

[0025] In some embodiments, when the mold is closed, the thickness of the adhesive between the two shell materials is controlled to be within 20 mm.

[0026] Compared with the prior art, the two-part molding method and molding die for the outer cylinder of a rotary sail described in this invention have the following advantages:

[0027] Through a collaborative structural design of "prefabricated adhesive tape + external hand lay-up + shell body", the rigidity and quality of the parting point are fully consistent with the shell body, achieving uniform rigidity of the entire swivel cylinder. The use of a single-sided flip-type two-part mold and an internal heating and curing method ensures that the two shell parts are formed and cured synchronously, significantly improving the uniformity of rigidity. The process eliminates the multiple splicing, counterweighting, and stress relief steps in the traditional multi-part process, simplifying the process flow and significantly improving production efficiency. The cost is controllable, the product qualification rate is high, and the application range is wide, allowing for flexible adjustments according to different swivel cylinder sizes and rigidity requirements.

[0028] This technology is suitable for producing rotating cylindrical components such as ship propellers and sails that require high uniformity of overall stiffness. It effectively solves the problems of uneven stiffness and unstable splicing quality in existing molding processes. By simplifying the process flow, reducing manual operation and equipment investment, it can significantly improve production efficiency, shorten the production cycle, reduce manufacturing costs, and improve product qualification rate and consistency. The reliable guarantee of stiffness for propellers and sails by this technology helps improve the stability and service life of propeller sails in actual operation, and has good engineering application value and prospects for promotion. Attached Figure Description

[0029] Figure 1 This is a schematic diagram of the single-sided flipping two-lobed outer cylinder mold structure according to an embodiment of the present invention;

[0030] Figure 2 This is a side view of the single-sided flip-type two-lobed outer cylinder mold according to an embodiment of the present invention;

[0031] Figure 3 This is a schematic diagram of the two-part mold in the mold-closing state according to an embodiment of the present invention;

[0032] Figure 3a for Figure 3 A magnified view of part A in the middle;

[0033] Figure 4 This is a schematic diagram of the "prefabricated adhesive tape + external hand lay-up + shell body" structure at the parting position of the rotary cylinder according to an embodiment of the present invention;

[0034] Figure 5 This is a schematic diagram of the rotary sail structure according to an embodiment of the present invention.

[0035] Explanation of reference numerals in the attached figures:

[0036] 1-Mold body, 2-Locking mechanism, 3-Heating belt, 4-Hydraulic tilting arm, 5-Mold flange, 6-Outer edge of flange, 7-Inner edge of flange, 8-Shell core material, 9-Shell fiber layup, 10-Outer hand layup layer, 11-Pre-fabricated adhesive tape, 100-Outer cylinder, 200-Inner tower, 300-Base. Detailed Implementation

[0037] To make the above-mentioned objects, features and advantages of the present invention more apparent and understandable, specific embodiments of the present invention will be described in detail below with reference to the accompanying drawings.

[0038] like Figures 1-4 As shown, a molding die for forming the outer cylinder of a rotary sail includes a die body 1 and a locking mechanism 2 disposed on the edge of the die body 1. The die body 1 is configured as a two-part die structure, with the two parts connected as one piece. The two parts are a fixed side and a flip-up side, respectively. The cavities of the fixed side die and the flip-up side die are both semi-cylindrical, so that at least one semi-cylindrical part of the die body 1 can be flipped on one side to join the two parts into a cylindrical structure.

[0039] The locking mechanism 2 is located on the radial edge of the mold body 1, that is, on the mating surface of the fixed side mold and the flip-up side mold. When the two semi-cylinder halves are joined, precise positioning is achieved through the edge locking mechanism 2, enabling the two semi-cylinder halves to close quickly and accurately, limiting the amount of misalignment during mold closing, and maintaining the mold in a closed state during the curing process. In some embodiments, multiple locking mechanisms 2 are provided on each side edge of the mold body 1, and the multiple locking mechanisms 2 are evenly distributed along the edge axial direction of the mold body 1, further ensuring that each part of the two semi-cylinder halves can close accurately.

[0040] A heating device is provided inside the mold body 1 to accelerate curing during the outer cylinder curing process. In some embodiments, the heating device can be a heating band 3, which extends along the length direction of the mold body 1. Multiple heating bands 3 are arranged evenly along an arc-shaped semicircle inside the mold body 1, ensuring uniform heating during the outer cylinder curing process. The length direction of the mold body is... Figure 1 The axial direction is shown in the figure.

[0041] A hydraulic flipping arm 4 is provided between the two semi-cylinders, connecting the two semi-cylinders, and capable of flipping and folding one of the semi-cylinders (the flippable side) towards the other semi-cylinder (the fixed side). In some embodiments, multiple hydraulic flipping arms 4 are provided, arranged in the middle part and near both ends of the mold body 1 along its length, so that the two ends of the semi-cylinders can be subjected to uniform force when flipping, thereby ensuring good uniformity of the final formed outer cylinder.

[0042] The molding die also includes a mold flange 5, which is a ring-shaped frame with a "Z"-shaped edge, including an outer flange 6 and an inner flange 7. The outer flange 6 is a vacuum extraction area, and its horizontal height is lower than that of the inner flange 7 to ensure vacuum adsorption on the upper surface when the mold is closed. The mold flange 5 works in conjunction with the locking mechanism 2, where the mold flange 5 provides a sealing surface and a mold closing reference surface; the locking mechanism 2 applies clamping force to keep the two mold halves closed.

[0043] In some embodiments, the mold profile deviation of the two-part mold structure can be controlled within ±15mm; the locking mechanism 2 limits the chordal misalignment of the mold closing gap to within ±5mm.

[0044] As part of the embodiments of the present invention, a molding process for forming the outer cylinder of a rotary sail is also provided, which uses the aforementioned single-sided flip-type two-lobed fiberglass mold for molding, the mold having a built-in heating function. The main body of the rotary sail is formed using a vacuum injection process, with stiffness adjustment only at the parting line through a collaborative structure of "pre-fabricated adhesive tape + external hand lay-up + shell body" to achieve uniform mass and stiffness distribution throughout the rotary sail.

[0045] The specific process includes the following steps:

[0046] (1) Mold preparation and inspection

[0047] The single-sided flip-type two-lobed fiberglass mold is adopted. The mold is divided into a fixed side mold and a flip-able side mold. The cavity is semi-cylindrical, and a locking mechanism is set on the mating surface to achieve fast and accurate mold closing. The mold shape deviation can be controlled within ±15mm, and the chordal misalignment of the mold closing seam is controlled within ±5mm. The outer surface of the product does not require additional treatment and directly meets the molding requirements. It provides a structural foundation for achieving equal quality and rigidity in the mold parting position.

[0048] The mold flange adopts a "Z"-shaped structure. The outer edge of the flange is the evacuation area, while the inner edge is used for sealing and mold positioning. The horizontal height of the outer edge of the flange is lower than that of the inner edge to ensure vacuum adsorption on the upper surface when the mold is closed. Vacuum sealing strips are affixed to the inner edge area of ​​the flange, and an evacuation port is reserved in the outer edge area.

[0049] (2) Fiber layup

[0050] Based on the stiffness requirements of the rotary cylinder, carbon fiber / glass fiber hybrid reinforcing dry fiber is selected; cross-laying is performed on the inner wall of each mold cavity, and the total thickness of the layup meets the design stiffness; the layup should cover the entire semi-cylindrical cavity and extend to the flange edge by about 50mm to facilitate subsequent vacuum sealing and ensure uniform circumferential stiffness and mass of the rotary cylinder shell.

[0051] Release cloth, flow guide net, and vacuum bag film are laid in sequence on top of the layers, with the edge of the vacuum bag film pressed against the outer edge of the Z-shaped flange in the air extraction area.

[0052] (3) Vacuum infusion and curing

[0053] Connect the suction port to the vacuum pump and the resin inlet to the resin tank to establish a vacuum system for each of the two mold halves. Start the vacuum pump to bring the pressure inside the vacuum bag to the required level. During the pressure holding stage of injection molding, the mold airtightness must ensure that the pressure drop does not exceed 0.005 MPa within 10 minutes to guarantee product quality and achieve equal mass and stiffness.

[0054] Open the resin feed valve to allow the vacuum-injected resin to evenly penetrate the dry fibers under differential pressure. Observe the resin flow front during injection to ensure the entire layup area is filled. After injection is complete, close the feed valve and maintain a vacuum state.

[0055] The heating process is initiated simultaneously on both mold halves to achieve synchronous curing of the two shell halves, ensuring consistent rigidity. Vacuum pressure is maintained throughout the curing process to prevent air bubbles. After curing, heating is turned off, and the shells are allowed to cool naturally to room temperature. The vacuum bag, flow guide net, and other auxiliary materials are removed, resulting in two independent semi-cylindrical shell blanks.

[0056] (4) Bonding at mold closing and mold parting positions

[0057] Apply a uniform layer of adhesive to the mold-closing seam end face of the fixed-side mold, with a thickness controlled within 20mm. After the mold cools to the specified temperature, activate the flipping mechanism to smoothly flip the flippable-side mold 180° and close it with the fixed-side mold. The locking mechanism automatically guides precise alignment, and the misalignment is manually checked.

[0058] Immediately after mold closing, use the locking mechanism to evenly lock the flange perimeter to ensure tight contact between the two halves, ideally squeezing out only a small amount of excess adhesive.

[0059] After the two shell halves are molded together, a prefabricated adhesive tape 11 matching the fiber material is placed inside the mold joint to bridge the two shell halves. Reinforcing fibers (such as glass cloth) are manually laid on the outside of the mold joint and coated with resin to form an outer hand lay-up layer 10, which forms a continuous load-bearing layer with the prefabricated adhesive tape and the shell body. This ensures that the prefabricated adhesive tape, outer hand lay-up layer, and shell body at the mold parting point are tightly bonded and work together to achieve equal mass and stiffness between the mold parting point and the shell body. The shell body includes a shell core material 8 and a shell fiber lay-up layer 9 located outside the shell core material 8.

[0060] The positioning structure at the mold parting point enables rapid and precise mold closing between the two mold halves, with a small closing gap and adhesive thickness controlled within 20mm. This avoids uneven rigidity and mass caused by misalignment at the parting point, while also improving mold closing efficiency. The process requires no additional splicing or stress relief steps, and the single-sided parting angle does not exceed 190°. Equal mass and rigidity of the rotating cylinder can be achieved simply through coordinating bonding at the parting point. The process is simple and cost-effective.

[0061] (5) Secondary heating and curing

[0062] The built-in heating system is restarted to heat the overall mold after mold closing, so that the bonding area at the mold parting position reaches the same degree of curing as the main body of the shell, thereby achieving equal rigidity of the whole.

[0063] The molding process of this invention employs a single-sided, flip-type, two-part fiberglass mold with built-in heating. The two cylindrical shell halves are simultaneously molded and cured using vacuum infusion, ensuring uniform stiffness and mass distribution in both the axial and circumferential directions of the shell body. After the two shell halves are molded together, an innovative collaborative structural design of "inner adhesive tape + outer adhesive tape + shell body" is adopted at the parting point. The pre-fabricated adhesive tape undertakes the main bonding function, while the outer adhesive tape strengthens the connection, forming an integrated load-bearing structure between the parting point and the shell body. This ensures equal mass and stiffness between the parting area and the main body area, while simplifying the process, improving production efficiency, and reducing manufacturing costs.

[0064] As part of the embodiments of the present invention, a rotary sail structure is also provided, employing the molding die and molding process described above, such as... Figure 5 As shown, the rotary sail structure includes an outer cylinder 100 and a base 300 disposed at the lower part of the outer cylinder 100. An inner tower 200 is also disposed inside the outer cylinder 100. The lower part of the inner tower 200 is connected to the base 300. The connection between the base 300 and the inner tower 200 is used to fix the base to the outer cylinder.

[0065] While the present invention has been disclosed above, it is not limited thereto. Any person skilled in the art can make various modifications and alterations without departing from the spirit and scope of the invention; therefore, the scope of protection of the present invention should be determined by the scope defined in the claims.

Claims

1. A forming mold for the outer cylinder of a rotary sail, characterized in that, The mold body (1) includes a mold body (1) and a locking mechanism (2) disposed on the edge of the mold body (1). The mold body (1) is configured as a two-part mold structure, and the two-part mold structure is connected as one unit. The two-part mold structure is a fixed side mold and a flip-up side mold, respectively. The cavities of the fixed side mold and the flip-up side mold are both semi-cylindrical. The locking mechanism is disposed on the mating surface of the fixed side mold and the flip-up side mold.

2. The molding die according to claim 1, characterized in that, The locking mechanism (2) on each side edge of the mold body (1) is provided in multiple ways, and the multiple locking mechanisms (2) are evenly distributed along the edge axis of the mold body (1).

3. The molding die according to claim 1, characterized in that, A heating device is provided inside the mold body (1).

4. The molding die according to claim 3, characterized in that, The heating device is configured as a heating band (3), which extends along the length of the mold body (1), and multiple heating bands (3) are configured, which are evenly arranged along an arc semicircle inside the mold body (1).

5. The molding die according to claim 1, characterized in that, A hydraulic flipping arm (4) is provided between the fixed side mold and the flippable side mold. The hydraulic flipping arm (4) can drive the flippable side mold to flip and fold towards the fixed side mold.

6. The molding die according to claim 1, characterized in that, The molding die also includes a mold flange (5), which is configured as an annular frame and the edge of the mold flange (5) is configured as a "Z" shaped structure.

7. A method for forming the outer cylinder of a rotary sail, characterized in that, include: Fiber-reinforced materials are laid on the inner walls of the cavities of the two mold halves; Vacuum injection is performed on the two mold halves, and the built-in heating device is activated to simultaneously solidify the shell material inside the two mold halves, forming the main body of the rotary cylinder shell; The flip-out side mold is flipped over and closed with the fixed side mold, and then locked by a locking structure. Precast adhesive tape is laid at the parting point of the two shell materials, and an external hand lay-up process is used to form a synergistic stress-bearing structure of "precast adhesive tape + external hand lay-up + shell body"; A second heating and curing process is performed to ensure that the bonding area at the mold parting point is cured to the same degree as the main body of the shell.

8. The molding method according to claim 7, characterized in that, The fiber reinforcement material is a carbon fiber / glass fiber hybrid reinforced dry fiber, which is laid on the inner wall of the cavity in a cross-layout manner.

9. The molding method according to claim 7, characterized in that, During the pressure holding stage of the vacuum injection, the mold airtightness should not depressurize by more than 0.005 MPa within 10 minutes.

10. The molding method according to claim 7, characterized in that, When the mold is closed, the thickness of the adhesive between the two shell materials should be controlled within 20mm.

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