Riveting expansion head

Abstract

The utility model relates to the technical field of punching of plates or pipes, in particular to a riveting expansion head which is assembled at a power output end of a driving mechanism and comprises an expansion rod and a fixing seat, the expansion rod and the fixing seat are integrally formed, the expansion rod is provided with a conical head used for expanding a pipe fitting, and a plurality of ribs are arranged on the conical surface of the conical head. The conical surface angle of the conical head ranges from 50 degrees to 60 degrees, the length of the conical head ranges from 12 mm to 15 mm, and the number of the ribs ranges from 6 to 8. According to the riveting expansion head, the ribs are arranged on the outer surface of the conical head, so that the riveting surface deforms, the holding force between a heat exchange tube and a tube plate is enhanced, and the connection stability is improved.

Description

Technical Field

[0001] The utility model relates to the technical field of plate or tube stamping, in particular to a riveting expansion head. Background Art

[0002] At present, there are three main methods for connecting heat exchange tubes and tube sheets: expansion connection, welding and expansion welding, in addition to the sticky expansion connection method and threaded connection method. The expansion connection method has the characteristics of simple structure, easy tube repair and replacement, and is widely used.

[0003] After searching, the patent with publication number CN102441616A discloses a shell and tube heat exchanger and a method for expanding and connecting its aluminum heat exchange tubes and steel tube sheets. A copper tube is added between the tube holes of the aluminum heat exchange tube and the steel tube sheet. During expansion, the copper tube and the steel tube sheet are expanded for the first time, and then the aluminum heat exchange tube and the copper tube are expanded for the second time. Under the premise of ensuring the sealing performance and tightness of the expansion, the use of copper in the heat exchanger is reduced, resources are saved, and production costs are reduced. It can be seen from the attached drawings that the end of the heat exchange tube close to the inner side of the tube sheet has a flange formed by riveting. Commonly used riveting requires an expansion head to achieve a stable connection between the heat exchange tube and the tube sheet. However, the end of the traditional expansion head is a smooth cone head structure. After the riveting is completed, the heat exchange tube is easily detached, and the stability is poor. Utility Model Content

[0004] In order to solve the problem that the cone head structure of the existing expansion head has poor riveting stability, which causes the heat exchange tube to fall off easily, the utility model provides a riveted expansion head, by arranging ribs on the outer surface of the cone head to deform the riveted surface, thereby enhancing the holding force between the heat exchange tube and the tube sheet and improving the connection stability.

[0005] The utility model provides a riveted expansion head, which is assembled at the power output end of a driving mechanism. The riveted expansion head includes an expansion rod and a fixing seat, which are integrally formed. The expansion rod has a cone head for expanding the pipe fitting, and a plurality of ribs are arranged on the cone surface of the cone head. The plurality of ribs are evenly distributed around the cone surface. By arranging the ribs on the cone surface, the holding force of the flange and the tube sheet can be strengthened during riveting, thereby ensuring the connection stability.

[0006] Furthermore, the cone angle of the cone head is 50° to 60°, which can ensure that the flange is riveted firmly.

[0007] Furthermore, the cone head has a length of 12 to 15 mm, which is suitable for different riveting requirements.

[0008] Furthermore, 6 to 8 ribs are provided to ensure the firmness of the overlap between the flange and the tube sheet.

[0009] Furthermore, the diameter of the fixing seat is larger than the diameter of the expansion rod, and a rubber sleeve is provided outside the expansion rod, one end of the rubber sleeve is connected to the fixing seat, and the other end extends to the cone head. The rubber sleeve first contacts the tube sheet to provide pre-positioning for the expansion connection of the cone head.

[0010] Furthermore, a mounting hole is provided in the expansion rod, and the mounting hole passes through the expansion rod and the fixing seat. The arrangement of the mounting hole facilitates the connection between the expansion head and the driving mechanism.

[0011] Furthermore, a mounting groove matched with the power output end is also provided in the fixing seat, and the mounting groove is communicated with the mounting hole. The setting of the mounting groove facilitates the fixing of the power output end.

[0012] Furthermore, the expansion rod is connected to the power output end through a bolt, and a relief hole for accommodating the bolt head is provided in the cone head, and the relief hole is communicated with the mounting hole. The bolt extends from the relief hole into the mounting hole and is screwed and fixed to the power output end.

[0013] The beneficial effects of the utility model are:

[0014] The utility model provides a riveted expansion head, which circumferentially arranges ribs on the conical surface of the cone head to deform the riveted surface while fixing it, thereby enhancing the holding force between the flange and the tube sheet and improving the connection stability between the heat exchange tube and the tube sheet. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] In order to more clearly illustrate the specific implementation methods of the utility model or the technical solutions in the prior art, the drawings required for use in the specific implementation methods or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are some implementation methods of the utility model. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0016] Figure 1 It is a three-dimensional schematic diagram of the riveted expansion head;

[0017] Figure 2 It is a plan view of the riveted expansion head;

[0018] Figure 3 yes Figure 2 AA surface schematic diagram in;

[0019] Figure 4 It is a schematic diagram of the riveting process;

[0020] In the figure, 1. expansion rod, 2. fixing seat, 3. cone head, 4. rib, 5. rubber sleeve, 6. mounting hole, 7. mounting groove, 8. avoidance hole, 9. heat exchange tube, 10. tube sheet. DETAILED DESCRIPTION

[0021] The technical solution of the present utility model will be clearly and completely described below in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present utility model, rather than all of the embodiments.

[0022] The traditional riveted expansion head includes an expansion rod 1 and a fixing seat 2. The expansion rod 1 and the fixing seat 2 are integrally formed. The expansion rod 1 has a cone head 3 for expanding the pipe fitting. The expansion head is connected to the power output end of the driving mechanism in the tube expander, so that the expansion rod 1 can drive the cone head 3 to move back and forth in the power output direction of the driving mechanism under the drive of the driving mechanism, thereby driving the cone head 3 to extend into the inner hole of the pipe fitting, expand the diameter of the end of the pipe fitting, and complete the riveting and fixing of the heat exchange tube 9 and the tube sheet 10. However, the cone surface of the existing cone head 3 is smooth. After the riveting is completed, the heat exchange tube 9 still has the risk of falling off, which affects the use. In order to strengthen the firmness of the riveting between the heat exchange tube 9 and the tube sheet 10, a riveted expansion head is designed, such as Figure 1 and 4 As shown, a plurality of ribs 4 are arranged on the conical surface of the conical head 3, and the ribs 4 are evenly distributed around the conical surface. When the conical head 3 is punched and riveted under the drive of the power output end, the ribs 4 can deform the riveted surface, that is, the contact part of the flange and the tube sheet 10 is deformed, thereby enhancing the holding force of the flange and the tube sheet 10, thereby improving the connection stability of the heat exchange tube 9 and the tube sheet 10.

[0023] In order to further ensure the firmness of the riveting, the cone angle of the cone head 3 is 50° to 60°. The length of the cone head 3 is 12 to 15 mm, which is set according to the actual riveting requirements. The outer diameter of the cone head 3 matches the outer diameter of the expansion rod 1 and is set according to the size of the riveted pipe opening. The ribs 4 are generally set 6 to 8 in the circumferential direction.

[0024] like Figure 2 and 3 As shown, in order to achieve the pre-positioning of the riveting, the diameter of the fixing seat 2 is larger than the diameter of the expansion rod 1, and a rubber sleeve 5 is provided outside the expansion rod 1. One end of the rubber sleeve 5 is connected to the fixing seat 2, and the other end extends to the cone head 3, and the length of the rubber sleeve 5 is slightly larger than the length of the expansion rod 1. When the expansion rod 1 extends into the tube hole of the heat exchange tube 9, the rubber sleeve 5 first touches the tube sheet 10, and the stamping direction of the cone head 3 is pre-positioned. The power output end of the driving mechanism continues to drive the cone head 3 to move downward and extend into the tube hole to complete the riveting flanging.

[0025] like Figure 3As shown, in order to facilitate the installation and use of the expansion head and the driving mechanism, a mounting hole 6 is provided in the expansion rod 1, and the mounting hole 6 runs through the expansion rod 1 and the fixing seat 2. A mounting groove 7 that matches the power output end is also provided in the fixing seat 2, and the mounting groove 7 is connected to the mounting hole 6. The expansion rod 1 is connected to the power output end by a bolt, and a avoidance hole 8 that can accommodate the bolt head is provided in the cone head 3, and the avoidance hole 8 is connected to the mounting hole 6. The power output end of the driving mechanism is placed in the mounting groove 7, and a screw hole that matches the bolt is opened at the output end, and then the bolt is inserted from the inside of the cone head 3 and screwed to the screw hole of the power output end through the mounting hole 6. The bolt head is restricted on the step in the avoidance hole 8, and the output end is restricted in the mounting groove 7, so as to achieve a stable connection between the expansion head and the tube expander and prevent the expansion head from falling off during the expansion process.

[0026] The above description is only illustrative rather than restrictive of the present invention. Those skilled in the art will understand that many modifications, changes or equivalents may be made without departing from the spirit and scope defined by the appended claims, but all will fall within the scope of protection of the present invention.

Claims

1. A riveting expansion head, assembled at the power output end of a driving mechanism, the riveting expansion head comprising an expansion rod (1) and a fixing seat (2), the expansion rod (1) and the fixing seat (2) being integrally formed, the expansion rod (1) having a cone head (3) for expanding a pipe fitting, characterized in that: A plurality of ribs (4) are arranged on the conical surface of the conical head (3), and the plurality of ribs (4) are evenly distributed around the circumference of the conical surface.

2. The riveting expansion head according to claim 1, characterized in that: The cone surface angle of the cone head (3) is 50° to 60°.

3. The riveting expansion head according to claim 1, characterized in that: The cone head (3) has a length of 12 to 15 mm.

4. The riveting expansion head according to claim 1, characterized in that: The ribs (4) are provided in 6 to 8 numbers.

5. The riveting expansion head according to claim 1, characterized in that: The diameter of the fixing seat (2) is greater than the diameter of the expansion rod (1). A rubber sleeve (5) is provided outside the expansion rod (1). One end of the rubber sleeve (5) is connected to the fixing seat (2), and the other end extends to the cone head (3).

6. The riveting expansion head according to claim 1, characterized in that: The expansion rod (1) is provided with a mounting hole (6), and the mounting hole (6) passes through the expansion rod (1) and the fixing seat (2).

7. The riveting expansion head according to claim 6, characterized in that: The fixing seat (2) is also provided with a mounting groove (7) matched with the power output end, and the mounting groove (7) is communicated with the mounting hole (6).

8. The riveting expansion head according to claim 7, characterized in that: The expansion rod (1) is connected to the power output end via a bolt, and a relief hole (8) capable of accommodating a bolt head is provided in the cone head (3), and the relief hole (8) is communicated with the mounting hole (6).

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