Connecting structure of special-shaped pressure vessel

Abstract

A connecting structure of a special-shaped pressure vessel comprises a skirt structure, an end frame, pins and a fiber winding layer, and specifically, the skirt structure is of a cylindrical structure extending out along the outer wall face of the pressure vessel; a plurality of pin holes are formed in the outer wall of the skirt structure; the whole end frame is of a cylindrical structure, the outer wall of the end frame extends by a certain length from the bottom end and is thinned to be machined into a variable-diameter shaft section, and the outer wall face of the variable-diameter shaft section and the inner wall of the skirt structure are installed in a matched mode. Pin holes in one-to-one correspondence with pin holes in the skirt structure are formed in the variable-diameter shaft section; the bottom of the inner wall of a pin hole in the variable-diameter shaft section is conical, and the bottom of a pin is limited; one end of the pin is a flat head, and the other end is a conical head matched with the bottom end of the pin hole in the end frame; conical heads of the pins sequentially extend into corresponding pin holes in the skirt structure and the end frame; the fiber winding layer is located on the outer wall face of the skirt structure to limit the outer sides of the pin holes. The connection reliability of the skirt pin structure is improved, and the bearing capacity of the whole structure is improved.

Description

Technical Field

[0001] The invention relates to a connection structure of a special-shaped pressure vessel, belonging to the field of pressure vessels. Background Art

[0002] Conventional pressure vessels can typically only connect to other external devices through localized connection structures on the cylindrical surface, and are unable to achieve axial connection. To achieve this axial connection, a skirt structure is required to extend from the cylindrical surface of the pressure vessel for assembly and connection with the end frame. This axial connection is achieved through the end-face connection structure of the end frame. During assembly, the composite skirt of a special-shaped pressure vessel is primarily connected radially to the metal end frame using a pin structure (special-shaped pressure vessels here refer to pressure vessels with skirt structures, while standard pressure vessels do not). Because threaded holes in the composite skirt structure are prone to thread slippage and cracking during assembly, resulting in poor reliability, a combination of smooth holes and smooth pins is required to connect the composite skirt to the metal end frame. Typically, when docking the skirt and end frame, the bonding surfaces are roughened, cleaned, and coated with glue before the end frame and skirt are docked into place. When installing the pins, the pin surfaces are dipped in glue to ensure an even and full adhesive layer, and then they are fitted with clearances to the skirt and end frame holes. The end frame and skirt are generally connected by double rows of pins. The pins are evenly distributed along the circumference. The two rows of pins are staggered and punched. There are dozens of pins in each row to improve reliability.

[0003] For the connection and assembly method of the above-mentioned equal diameter pin structure, the pins and the pin holes on the skirt and end frame only rely on the bonding force generated by the adhesive to resist the external load, which has poor reliability. Figure 1 As shown, it is easy to loosen and fall out under the action of external load, causing safety hazards. Summary of the Invention

[0004] The technical problem solved by the present invention is: to overcome the shortcomings of the existing technology, to provide a connection structure for special-shaped pressure vessels, and to solve the problem that the connection structure between the composite skirt of the special-shaped pressure vessel and the metal end frame pin is prone to loosening and falling out under the action of external load.

[0005] The technical solution of the present invention is: a connection structure of a special-shaped pressure vessel, comprising: a skirt structure, an end frame, a pin and a fiber winding layer, wherein the skirt structure is a composite material, specifically:

[0006] The skirt structure is a cylindrical structure extending from the outer wall of the pressure vessel along the axial direction of the pressure vessel. One end is fixed to the pressure vessel, and the other end is assembled and connected to the end frame. A number of pin holes are provided on the outer wall of the skirt structure. The direction away from the pressure vessel is defined as the distal end, and the direction close to the pressure vessel is defined as the bottom end.

[0007] The end frame is a cylindrical structure as a whole. The outer wall of the end frame is extended from the bottom end and thinned to form a variable diameter shaft section. The outer wall surface of the variable diameter shaft section is nested with the inner wall of the skirt structure. The variable diameter shaft section is provided with pin holes corresponding to those on the skirt structure. The bottom of the inner wall of the pin hole on the variable diameter shaft section is tapered to limit the bottom of the pin.

[0008] One end of the pin is flat, and the other end is a cone head that fits into the bottom of the pin hole on the end frame; the cone head of the pin extends into the corresponding pin holes on the skirt structure and the end frame in turn to fix the relative position of the skirt structure and the end frame;

[0009] The fiber winding layer is located on the outer wall surface of the skirt structure, covers all the pin holes, and limits the outer sides of the pin holes.

[0010] Preferably, the cross-sectional shape of the skirt structure is designed to follow the cross-sectional shape of the special-shaped pressure vessel, and the cross-sectional shape of the special-shaped pressure vessel can be circular, elliptical, rectangular, or triangular; the cross-sectional shape refers to the cross-sectional shape perpendicular to the axial direction of the special-shaped pressure vessel.

[0011] Preferably, the inner wall of the variable diameter shaft section of the end frame is thinned by extending a length from the bottom end, which is recorded as the inner wall of the variable diameter shaft section. The length of the inner wall of the variable diameter shaft section should be greater than the distance from the farthest pin hole to the bottom of the end frame.

[0012] A threaded hole is provided along the axial direction at the top of the end frame for connection with other external devices.

[0013] Preferably, the inner wall surface of the variable diameter shaft section of the end frame is provided with two circles of protruding annular structures, and the pin holes are evenly distributed in the area where the two circles of annular structures are located; the conical structure at the bottom of the pin hole is located at the bottom of the protruding annular structure, thereby increasing the reliability of fixation.

[0014] Preferably, the two circles of pin holes are staggered; 80 to 120 radial pin holes are evenly arranged along the circumferential direction in each circle.

[0015] Preferably, the surface of the pin is sandblasted to increase the bonding strength between the pin and the inner wall of the pin hole.

[0016] Preferably, when the pins are assembled into the pin holes of the end frame and the skirt structure, the pins are dipped in glue and knocked into the pin holes.

[0017] Preferably, the carbon fiber composite material layer is wound on the outer surface of the skirt structure by a conventional wet process, and is positioned on the outer side of the pin hole after being heated and cured;

[0018] The outer surface of the skirt structure is polished before winding to improve the fit between the carbon fiber composite material layer and the skirt structure.

[0019] Preferably, the bottom of the pin and the bottom of the pin hole are both conical surfaces that form an angle of 29° to 31° with the horizontal end surface of the end frame.

[0020] Preferably, the pin and the pin hole adopt a basic hole system H8 / n7 interference fit to prevent the pin from moving.

[0021] Compared with the prior art, the present invention has the following advantages:

[0022] The present invention realizes inner limitation of the pin hole by designing the cone shape of the pin bottom; realizes outer limitation of the pin hole by designing a carbon fiber composite material layer wrapped around the outer side of the pin head; this reinforcement structure improves the connection reliability of the skirt pin structure and improves the bearing capacity of the entire structure. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 A cross-sectional view of the composite skirt and metal end frame connected by equal diameter pins;

[0024] Figure 2 This is a cross-sectional view of the tapered pin of the present invention connecting the composite material skirt and the metal end frame.

[0025] Figure 3 Schematic diagram of the positional relationship between the special-shaped pressure vessel and the skirt structure.

[0026] Figure symbols: 1-skirt structure, 2-end frame, 3-cone-head pin designed according to the present invention, 4-carbon fiber composite material layer, 5-equal diameter pin, 6-pressure vessel. DETAILED DESCRIPTION

[0027] The present invention provides a connection structure for special-shaped pressure vessels, the key parts of which are Figure 2 The combination design of the cone head pin limiter and the fiber winding layer limiter. Compared with the connection structure of equal diameter pins, this combination structure achieves reliable limiter, will not fall out under external load, and has higher connection reliability.

[0028] Two ring belts are added to the inner side of the metal end frame to assemble the composite skirt and the metal end frame, and the relative positions of the skirt and the end frame are fixed by positioning pins. Dozens of radial pin holes are evenly distributed along the annular direction, and two rows of pin holes are staggered and punched. The pin hole section in the ring belt of the metal end frame is machined into a tapered hole. The bottom of the pin is designed to be in the shape of a cone head that matches the annular strip, and the bottom of the pin matches the contact surface of the tapered hole. The surface of the pin is sandblasted, and the pin is dipped in glue and knocked into the pin hole to complete the assembly of the pin. At the same time, in order to achieve the limiting effect on the outside of the pin hole, a layer of carbon fiber composite material is wrapped around the outside of the pin head. There is no thread set on the circumference of the pin, and the pin hole is also a smooth hole to avoid the thread slipping and cracking that is very easy to occur during the assembly process with the composite skirt.

[0029] further:

[0030] A connection structure for a special-shaped pressure vessel includes: a skirt structure 1, an end frame 2, a pin 3, and a fiber winding layer 4, wherein the skirt structure is a composite material. Specifically:

[0031] The skirt structure 1 is a cylindrical structure extending from the outer wall of the pressure vessel 6 along the axial direction of the pressure vessel. One end is fixedly connected to the pressure vessel and the other end is assembled and connected to the end frame. A number of pin holes are provided on the outer wall of the skirt structure. The direction away from the pressure vessel is defined as the far end, and the direction close to the pressure vessel is defined as the bottom end. The positional relationship between the special-shaped pressure vessel and the skirt structure is shown in the following three-dimensional cross-sectional diagram. Figure 3 As shown, the cross section in the figure is parallel to the axial direction of the pressure vessel.

[0032] The end frame 2 is a cylindrical structure as a whole. The outer wall of the end frame is extended from the bottom end and thinned to form a variable diameter shaft section. The outer wall surface of the variable diameter shaft section is mounted in conjunction with the inner wall of the skirt structure. The variable diameter shaft section is provided with pin holes corresponding to those on the skirt structure. The bottom of the inner wall of the pin hole on the variable diameter shaft section is tapered to limit the bottom of the pin.

[0033] One end of the pin 3 is a flat head, and the other end is a cone head that matches the bottom end of the pin hole on the end frame; the cone head of the pin sequentially extends into the corresponding pin holes on the skirt structure and the end frame to fix the relative position of the skirt structure and the end frame; Figure 1 The traditional equal diameter pin 5 improves the connection reliability of the pin structure;

[0034] The fiber winding layer 4 is located on the outer wall of the skirt structure, and can cover all the pin holes and limit the outer sides of the pin holes.

[0035] The cross-sectional shape of the skirt structure 1 is designed to follow the cross-sectional shape of the special-shaped pressure vessel, and the cross-sectional shape of the special-shaped pressure vessel can be circular, elliptical, rectangular, triangular or other irregular shapes. The cross-sectional shape is a cross-sectional shape perpendicular to the axis of the special-shaped pressure vessel.

[0036] The inner wall of the reducing shaft section of the end frame 2 is thinned by extending a length from the bottom end, which is recorded as the reducing shaft section inner wall. The length of the reducing shaft section inner wall should be greater than the distance from the farthest pin hole to the bottom of the end frame;

[0037] A threaded hole is provided along the axial direction at the top of the end frame for connecting with other external devices;

[0038] A threaded hole is provided at the top end of the end frame 2 along the axial direction for connection with other external devices.

[0039] The inner wall surface of the variable diameter shaft section of the end frame is provided with two circles of protruding annular structures, and the pin holes are evenly distributed in the area where the two circles of annular structures are located; the conical structure at the bottom of the pin hole is located at the bottom of the protruding annular structure, which increases the reliability of fixation.

[0040] The two circles of pin holes are staggered; dozens of radial pin holes are evenly distributed along the annular direction in each circle.

[0041] The surface of the pin 3 is sandblasted to increase the bonding strength between the pin and the inner wall of the pin hole.

[0042] When assembling the pins into the pin holes of the end frame and skirt structure, dip the pins in glue and knock them into the pin holes.

[0043] The pin and the pin hole adopt the basic hole system H8 / n7 interference fit, which is used to increase the reliability of the connection structure and prevent the pin from moving.

[0044] The carbon fiber composite layer is wrapped around the outer surface of the skirt structure using a traditional wet process. After being heated and cured, it is positioned outside the pin hole. Before wrapping, the outer surface of the skirt structure is polished to improve the fit between the carbon fiber composite layer and the skirt structure.

[0045] The bottom of the pin and the bottom of the pin hole are both conical surfaces that form an angle of 29° to 31° with the horizontal end surface of the end frame.

[0046] Example:

[0047] Two annular bands are added to the inner side of the metal end frame, and the composite skirt is assembled with the metal end frame. The relative position of the skirt and end frame is fixed with locating pins to prevent changes in their relative position during subsequent processing. Dozens of radial pin holes are machined evenly along the circumference, with two rows of pin holes punched in offset positions. The pin hole sections within the metal end frame annular bands are machined into tapered holes to mate with the bottom of the pin to achieve a position-limiting effect on the inside of the pin hole. The bottom of the pin is designed with a cone head shape that matches the annular bands to ensure full contact between the bottom of the pin and the annular bands. The contact surface between the bottom of the pin and the tapered hole is a conical surface at an angle of 30°±1° to the horizontal end face of the end frame. The pin surface is sandblasted to increase the bonding strength between the pin and the inner wall of the pin hole. The pin is dipped in glue and hammered into the pin hole to complete the pin assembly. Furthermore, to achieve a position-limiting effect on the outside of the pin hole, a layer of carbon fiber composite material is wrapped around the outside of the pin head. Before winding, the cylindrical surface outside the pin hole is polished to improve the fit between the carbon fiber composite layer and the skirt. The carbon fiber composite layer is wound onto the outside of the skirt using a traditional wet process and then heated and cured to achieve position control outside the pin hole.

[0048] The contents not described in detail in the specification of the present invention belong to the prior art known to those skilled in the art.

Claims

1. A connection structure for special-shaped pressure vessels, characterized in that include: Skirt structure, end frame, pins and fiber winding layer, wherein the skirt structure is a composite material, specifically: The skirt structure is a cylindrical structure extending from the outer wall of the pressure vessel along the axial direction of the pressure vessel. One end is fixed to the pressure vessel, and the other end is assembled and connected to the end frame. A number of pin holes are provided on the outer wall of the skirt structure. The direction away from the pressure vessel is defined as the distal end, and the direction close to the pressure vessel is defined as the bottom end. The end frame is a cylindrical structure as a whole. The outer wall of the end frame is extended from the bottom end and thinned to form a variable diameter shaft section. The outer wall surface of the variable diameter shaft section is nested with the inner wall of the skirt structure. The variable diameter shaft section is provided with pin holes corresponding to those on the skirt structure. The bottom of the inner wall of the pin hole on the variable diameter shaft section is tapered to limit the bottom of the pin. One end of the pin is flat, and the other end is a cone head that fits into the bottom of the pin hole on the end frame; the cone head of the pin extends into the corresponding pin holes on the skirt structure and the end frame in turn to fix the relative position of the skirt structure and the end frame; The fiber winding layer is located on the outer wall surface of the skirt structure, covers all the pin holes, and limits the outer sides of the pin holes.

2. The connection structure of a special-shaped pressure vessel according to claim 1, characterized in that: The cross-sectional shape of the skirt structure is designed to follow the cross-sectional shape of the special-shaped pressure vessel. The cross-sectional shape of the special-shaped pressure vessel can be circular, elliptical, rectangular, or triangular. The cross-sectional shape refers to the cross-sectional shape perpendicular to the axial direction of the special-shaped pressure vessel.

3. The connection structure of a special-shaped pressure vessel according to claim 1, characterized in that: On the inner wall of the end frame reducing shaft section, a length extending from the bottom end is thinned and processed, which is recorded as the reducing shaft section inner wall. The length of the reducing shaft section inner wall should be greater than the distance from the farthest pin hole to the bottom of the end frame; A threaded hole is provided along the axial direction at the top of the end frame for connection with other external devices.

4. The connection structure of a special-shaped pressure vessel according to claim 3, characterized in that: The inner wall surface of the variable diameter shaft section of the end frame is provided with two circles of protruding annular structures, and the pin holes are evenly distributed in the area where the two circles of annular structures are located; the conical structure at the bottom of the pin hole is located at the bottom of the protruding annular structure, which increases the reliability of fixation.

5. The connection structure of a special-shaped pressure vessel according to claim 4, characterized in that: The two circles of pin holes are staggered; 80 to 120 radial pin holes are evenly arranged along the circumferential direction in each circle.

6. The connection structure of a special-shaped pressure vessel according to claim 1, characterized in that: The pin surface is sandblasted to increase the bonding strength between the pin and the inner wall of the pin hole.

7. The connection structure of a special-shaped pressure vessel according to claim 1, characterized in that: When assembling the pins into the pin holes of the end frame and skirt structure, dip the pins in glue and knock them into the pin holes.

8. The connection structure of a special-shaped pressure vessel according to claim 1, characterized in that: The carbon fiber composite material layer is wrapped around the outer surface of the skirt structure using a traditional wet process, and after being heated and cured, it limits the outer side of the pin hole; The outer surface of the skirt structure is polished before winding to improve the fit between the carbon fiber composite material layer and the skirt structure.

9. The connection structure of a special-shaped pressure vessel according to claim 1, characterized in that: The bottom of the pin and the bottom of the pin hole are both conical surfaces that form an angle of 29° to 31° with the horizontal end surface of the end frame.

10. The connection structure of a special-shaped pressure vessel according to claim 1, characterized in that: The pin and the pin hole adopt the basic hole system H8 / n7 interference fit to prevent the pin from moving.

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