Plug for heat exchanger heat transfer tube plugging

Abstract

The present disclosure belongs to the field of nuclear power maintenance technology, and specifically relates to a plug for plugging heat transfer tubes of heat exchangers. In the embodiment of the present disclosure, the body and the cam form an eccentric structure, so that when the screw is rotated, the cam can rotate relatively eccentrically around the pin shaft and the body under the action of its own weight, and then the outer contours of the cam and the body are engaged with the inner wall of the heat transfer tube to form a support; on this basis, when the screw is continuously rotated in the direction of the body, the conical structure at the other end of the screw expands the outer diameter of the opening at the other end of the body, so that the other end of the body forms a plug for the heat transfer tube, which is easy to operate, has a good plugging effect, and does not require a large operating space, so that the plugging operation on both sides of the heat transfer tube inlet and outlet can be completed on one side of the heat transfer tube in a limited space.

Description

Technical Field

[0001] The invention belongs to the technical field of nuclear power maintenance, and in particular relates to a plug used for plugging heat transfer tubes of a heat exchanger. Background Art

[0002] During the service life of a shell and tube heat exchanger, it is impossible to completely prevent the damage of the heat transfer tube. Therefore, it is necessary to seal both ends of the damaged or defective individual heat transfer tubes (hereinafter referred to as plugging tubes) to remove them from service, thereby ensuring the safe and reliable operation of the heat exchanger.

[0003] In the related technologies, pipe plugging techniques may include welding pipe plugging, explosion pipe plugging, mechanical pipe plugging, etc. In the above technologies, pipe plugging operations are usually performed on both sides of the heat transfer tube of the heat exchanger. However, when the operating space on one side of the shell and tube heat exchanger is limited, or when the head on one side of the shell and tube heat exchanger is inconvenient to disassemble and assemble, pipe plugging is difficult to perform. Therefore, how to achieve effective pipe plugging in a limited operating space has become a technical problem that needs to be solved urgently. Summary of the invention

[0004] In order to overcome the problems existing in the related art, a plug for blocking a heat transfer tube of a heat exchanger is provided.

[0005] According to one aspect of an embodiment of the present disclosure, a plug for plugging a heat transfer tube of a heat exchanger is provided, wherein the plug for plugging a heat transfer tube of a heat exchanger comprises: a pin shaft, a cam, a body, and a screw;

[0006] The cam is provided with an eccentric through hole along the axial direction, and the pin shaft is inserted through the eccentric through hole;

[0007] One end of the pin extending out of the eccentric through hole is fixedly connected to one end of the body;

[0008] An opening is formed at the other end of the body, and a threaded hole is formed in the body facing the opening;

[0009] One end of the screw is threadedly connected in the threaded hole, and the other end of the screw has a cone-shaped structure;

[0010] When the center of the cam coincides with the center of the body, the plug for plugging the heat transfer tube of the heat exchanger can enter the heat transfer tube;

[0011] The plug for plugging the heat transfer tube of the heat exchanger is located in the heat transfer tube, and when the screw is continuously rotated, the cam can rotate relatively eccentrically around the pin shaft and the body under the action of its own weight until the outer contours of the cam and the body are stuck on the inner wall of the heat transfer tube;

[0012] When the outer contours of the cam and the body are stuck on the inner wall of the heat transfer tube and the screw is continuously rotated toward the body, the conical structure at the other end of the screw enlarges the outer diameter of the opening at the other end of the body, so that the other end of the body blocks the heat transfer tube.

[0013] In a possible implementation, the screw is a hexagon socket screw, and the plug for plugging the heat transfer tube of the heat exchanger further includes: a hexagonal wrench;

[0014] The hexagonal wrench is used to tighten the hexagon socket screw.

[0015] In a possible implementation, the plug for plugging the heat transfer tube of the heat exchanger further includes: a connecting rod and a torque wrench adapter block.

[0016] One end of the connecting rod is connected to the hexagonal wrench, and the other end of the connecting rod is connected to the torque wrench adapter block.

[0017] In a possible implementation, one end of the hexagonal wrench is connected to the hexagon socket screw via a wire retaining spring or a magnet.

[0018] In a possible implementation, the plug for plugging the heat transfer tube of the heat exchanger further includes a conical ferrule;

[0019] The conical sleeve is sleeved on the other end of the screw to form a conical structure.

[0020] In a possible implementation, the other end of the pin extending out of the eccentric through hole is provided with a baffle.

[0021] In a possible implementation, knurling is provided on an outer side surface of the cam and an outer side surface of the body close to one end of the cam.

[0022] In a possible implementation, the knurling on the outer side surface of the cam and the outer side surface of the body close to one end of the cam are circumferential or axial knurling.

[0023] In a possible implementation, knurling is provided on the outer side of the opening at the other end of the body.

[0024] In a possible implementation, the knurling is circumferential on the outer side surface of the other end of the body.

[0025] The beneficial effects of the present invention are as follows: in the disclosed embodiment, the body and the cam form an eccentric structure, so that when the screw is rotated, the cam can make a relative eccentric rotation around the pin shaft and the body under the action of its own weight, and then the outer contours of the cam and the body are engaged with the inner wall of the heat transfer tube to form a support; on this basis, when the screw is continuously rotated in the direction of the body, the conical structure at the other end of the screw expands the outer diameter of the opening at the other end of the body, so that the other end of the body forms a blockage on the heat transfer tube, which is easy to operate, has a good blocking effect, and does not require too much operating space, thereby completing the blocking operation on both sides of the inlet and outlet of the heat transfer tube on one side of the heat transfer tube within a limited space. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 The figure is a side view of a plug for plugging a heat transfer tube of a heat exchanger according to an exemplary embodiment.

[0027] Figure 2 The diagram is a left side view of a plug for plugging a heat transfer tube of a heat exchanger according to an exemplary embodiment.

[0028] Figure 3 The figure is a cross-sectional view of a plug for plugging a heat transfer tube of a heat exchanger according to an exemplary embodiment.

[0029] Figure 4 The present invention is a cross-sectional view of a plug for plugging a heat transfer tube of a heat exchanger in a use state according to an exemplary embodiment.

[0030] Figure 5 The present invention is a cross-sectional view of a plug for plugging a heat transfer tube of a heat exchanger in a use state according to an exemplary embodiment. DETAILED DESCRIPTION

[0031] The present invention is further described in detail below with reference to the accompanying drawings and specific embodiments.

[0032] Figure 1 The figure is a side view of a plug for plugging a heat transfer tube of a heat exchanger according to an exemplary embodiment. Figure 2 The diagram is a left side view of a plug for plugging a heat transfer tube of a heat exchanger according to an exemplary embodiment. Figure 3 The figure is a cross-sectional view of a plug for plugging a heat transfer tube of a heat exchanger according to an exemplary embodiment. Figure 4 The present invention is a cross-sectional view of a plug for plugging a heat transfer tube of a heat exchanger in a use state according to an exemplary embodiment. Figure 5 FIG. 1 is a cross-sectional view of a plug for plugging a heat transfer tube of a heat exchanger in a state of use according to an exemplary embodiment. Figures 1 to 5 As shown, the plug for plugging the heat transfer tube of the heat exchanger may include: a pin 5, a cam 3, a body 1, and a screw 4;

[0033] As an example of this embodiment, the cam 3 may have an eccentric through hole axially opened, and the pin 5 may be inserted through the eccentric through hole; one end of the pin 5 extending out of the eccentric through hole may be fixedly connected to one end of the body 1;

[0034] The other end of the body 1 may have an opening. For example, the interior of the body 1 may be a hollow stepped structure, or the body 1 may be a cylindrical structure or a cup-shaped structure. The disclosed embodiment does not limit the structure of the body 1. The opening at the other end of the body 1 may be a thin-walled tapered hole structure. For example, the side wall thickness of the opening at the other end of the body 1 may be about 0.5 mm (millimeter) -1 mm, which may facilitate smooth plastic deformation of the opening at the other end of the body 1 when it is compressed. A threaded hole may be provided at the position facing the opening inside the body 1.

[0035] One end of the screw 4 can be inserted from the other end opening of the body 1 and can be threadedly connected in the threaded hole. The other end of the screw 4 has a conical structure, and the inner diameter of the conical structure can gradually increase from close to the body 1 to far away from the body 1.

[0036] The outer diameters of the body 1 and the cam 3 can be slightly smaller than the inner diameter of the heat transfer tube 6. The maintenance personnel can coincide the center of the cam 3 with the center of the body 1 and insert the plug used for plugging the heat transfer tube of the heat exchanger into the required position of the heat transfer tube 6.

[0037] When the plug for blocking the heat exchanger heat transfer tube is placed in the heat transfer tube 6, the maintenance personnel can use a wrench to rotate the screw 4. When the screw 4 is continuously rotated, the cam 3 can make a relative eccentric rotation around the pin shaft 5 and the main body 1 under the action of its own weight, and become eccentric with the main body 1. The main body 1 and the cam 3 gradually stagger with each other until the outer contours of the cam 3 and the main body 1 are stuck on the inner wall of the heat transfer tube 6.

[0038] When the outer contours of the cam 3 and the body 1 are stuck on the inner wall of the heat transfer tube 6, a frictional engagement is formed between the cam 3 and the body 1 and the heat transfer tube 6, and the entire plug is fixed on the inner wall of the heat transfer tube 6 and cannot be rotated further, thereby limiting the plug used for plugging the heat transfer tube of the heat exchanger to the corresponding position in the heat transfer tube 6. On this basis, the maintenance personnel can then rotate the screw 4 in the direction of the body 1. Since the body 1 and the cam 3 no longer move, the screw 4 can form a threaded transmission along the threaded hole of the body 1, thereby driving the conical structure at the other end of the screw 4 to move toward the opening at the other end of the body 1, and then radially extruding the side wall of the opening at the other end of the body 1, forcing the opening at the other end of the body 1 to form a plastic deformation until it contacts the inner wall of the heat transfer tube 6;

[0039] As the screw 4 continues to rotate, the outer wall of the opening at the other end of the body 1 can bite into the inner wall of the heat transfer tube 6, thereby sealing the heat transfer tube 6.

[0040] In the disclosed embodiment, the body and the cam form an eccentric structure, so that when the screw is rotated, the cam can make relative eccentric rotation around the pin shaft and the body under the action of its own weight, and then the outer contours of the cam and the body are engaged with the inner wall of the heat transfer tube to form support; on this basis, when the screw is continuously rotated in the direction of the body, the conical structure at the other end of the screw enlarges the outer diameter of the opening at the other end of the body, so that the other end of the body forms a blockage on the heat transfer tube, which is easy to operate and has a good blocking effect, and does not require too much operating space. Therefore, the blocking operation on both sides of the inlet and outlet of the heat transfer tube can be completed on one side of the heat transfer tube within a limited space.

[0041] In one possible implementation, Figure 4 and Figure 5 As shown, the screw 4 may be a hexagon socket screw, and the plug used for plugging the heat transfer tube of the heat exchanger may also include: a hexagonal wrench 9; the maintenance personnel may use the hexagonal wrench 9 to turn the screw 4, further reducing the required operating space.

[0042] In one possible implementation, Figure 5 As shown, the plug for plugging the heat transfer tube of the heat exchanger may also include: a connecting rod 10 and a torque wrench adapter block 11. One end of the connecting rod 10 may be connected to the hexagonal wrench 9, and the other end of the connecting rod 10 may be connected to the torque wrench adapter block 11. The connecting rod 10 of a suitable length may be selected according to the need for plugging the tube. In one example, the interconnected screws 4, the body 1, and the cam 3 may be transported to the position of the heat transfer tube 6 at the distal tube sheet 8 through the proximal tube sheet 7 through the heat transfer tube 6 by the connecting rod 10 and the hexagonal wrench 9, and the plugging of the tube is completed by rotating the torque wrench adapter block 11. In this way, the plugging operation of the distal end of the heat transfer tube 6 may be conveniently performed by the connecting rod 10.

[0043] In a possible implementation, one end of the hexagonal wrench 9 can be connected to the screw 4 through a wire clip or a magnet. In this way, the connection between the hexagonal wrench 9 and the screw 4 can be made more stable, and the slippage between the hexagonal wrench 9 and the hexagonal screw 4 can be effectively avoided.

[0044] In a possible implementation, the plug for plugging the heat transfer tube of the heat exchanger further includes a conical sleeve 2; the conical sleeve 2 can be sleeved on the other end of the screw 4 to form a conical structure. In this way, the size of the conical structure at the other end of the screw 4 can be changed as needed to more flexibly adapt to heat transfer tubes of different sizes.

[0045] In one possible implementation, Figure 2 As shown, the other end of the pin 5 extending out of the eccentric through hole may have a baffle 12. The cam 3 may be arranged between the baffle and one end of the body 1, and the baffle 12 effectively prevents the cam 3 from being separated from the body 1.

[0046] In a possible implementation, the outer side surface of the cam 3 and the outer side surface of the body 1 near one end of the cam 3 may be provided with knurling. The knurling provided on the outer side surface of the cam 3 and the outer side surface of the body 1 near one end of the cam 3 is circumferential or axial knurling. In this way, the friction between the cam 3, the body 1 and the inner wall of the heat transfer tube 6 can be increased, effectively preventing the cam 3 and the body 1 from slipping off the inner wall of the heat transfer tube 6 after being stuck on the inner wall of the heat transfer tube 6.

[0047] In a possible implementation, the outer side of the opening at the other end of the body 1 may also be knurled. In this way, the friction between the opening at the other end of the body 1 and the inner wall of the heat transfer tube 6 can be increased, effectively preventing the opening at the other end of the body 1 from slipping with the inner wall of the heat transfer tube 6.

[0048] Among them, the knurling is circumferential on the outer side surface of the opening at the other end of the main body 1. When the opening at the other end of the main body 1 is squeezed and expanded to engage with the inner wall of the heat transfer tube 6, the circumferential knurling on the outer side surface of the opening of the main body 1 is perpendicular to the relative displacement of the opening at the other end of the main body 1 and the inner wall of the heat transfer tube 6, which can increase the friction between the opening at the other end of the main body 1 and the inner wall of the heat transfer tube 6, and further effectively prevent the opening at the other end of the main body 1 from slipping from the inner wall of the heat transfer tube 6.

[0049] Application Examples

[0050] Step 1: The hexagonal wrench 9 can be connected to the screw 4 by means of the elastic force of the steel wire spring at the front end of the hexagonal wrench 9 or the suction force of the magnet, and the connecting rod 10 and the torque wrench adapter block 11 are connected in sequence at the rear end of the hexagonal wrench 9, and the output torque of the torque wrench is adjusted to the required value, which is mainly determined according to the material of the heat transfer tube 6;

[0051] Step 2: The screws 4, the body 1 and the cam 3 connected to each other can be inserted into the heat transfer tube 6 of the heat exchanger at the position of the distal tube sheet 8 through the connecting rod 10, and the torque wrench adapter block 11, the connecting rod 10 and the hexagonal wrench 9 can be rotated by using a torque wrench to drive the body 1 to rotate;

[0052] Step 3: The pipe plugging personnel continuously rotates the torque wrench until the required output torque value is reached, completes the pipe plugging operation on the far end of the heat transfer pipe, and withdraws the connecting rod 10 from the inside of the heat transfer pipe 6 of the heat exchanger, and removes the connecting rod 10;

[0053] Step 4: Connect the hexagonal wrench 9 and the screw 4 together by using the elastic force of the steel wire clip at the front end of the hexagonal wrench 9 or the suction force of the magnet, and adjust the output torque of the torque wrench to the required value according to the material of the heat transfer tube 6 of the heat exchanger;

[0054] Step 5: Use the hexagonal wrench 9 to insert the interconnected screws 4, the body 1 and the cam 3 into the heat exchanger heat transfer tube 6 at the position near the tube sheet 7, and use the torque wrench to rotate the torque and the hexagonal wrench 9 to drive the body 1 to rotate;

[0055] Step 6: The pipe plugging personnel continuously rotates the torque wrench until the required output torque value is reached to complete the pipe plugging operation at the near end of the heat transfer pipe, that is, to achieve the pipe plugging operation at the near end and the far end of the heat transfer pipe.

[0056] Obviously, those skilled in the art can make various changes and modifications to the present invention without departing from the spirit and scope of the present invention. If these modifications and variations fall within the scope of the claims of the present invention and their equivalents, the present invention is also intended to include these modifications and variations.

Claims

1. A plug for plugging a heat transfer tube of a heat exchanger, characterized in that: The plug for plugging the heat transfer tube of the heat exchanger comprises: a pin, a cam, a body, and a screw; The cam is provided with an eccentric through hole along the axial direction, and the pin shaft is inserted through the eccentric through hole; One end of the pin extending out of the eccentric through hole is fixedly connected to one end of the body; An opening is formed at the other end of the body, and a threaded hole is formed in the body facing the opening; One end of the screw is threadedly connected in the threaded hole, and the other end of the screw has a cone-shaped structure; When the center of the cam coincides with the center of the body, the plug for plugging the heat transfer tube of the heat exchanger can enter the heat transfer tube; The plug for plugging the heat transfer tube of the heat exchanger is located in the heat transfer tube, and when the screw is continuously rotated, the cam can rotate relatively eccentrically around the pin shaft and the body under the action of its own weight until the outer contours of the cam and the body are stuck on the inner wall of the heat transfer tube; When the outer contours of the cam and the body are stuck on the inner wall of the heat transfer tube and the screw is continuously rotated toward the body, the conical structure at the other end of the screw enlarges the outer diameter of the opening at the other end of the body, so that the other end of the body blocks the heat transfer tube.

2. The plug for blocking a heat transfer tube of a heat exchanger according to claim 1, characterized in that: The screw is a hexagon socket screw, and the plug for plugging the heat transfer tube of the heat exchanger further includes: a hexagonal wrench; The hexagonal wrench is used to tighten the hexagon socket screw.

3. The plug for blocking the heat transfer tube of a heat exchanger according to claim 2, characterized in that: The plug for plugging the heat transfer tube of the heat exchanger also includes: a connecting rod and a torque wrench adapter block; One end of the connecting rod is connected to the hexagonal wrench, and the other end of the connecting rod is connected to the torque wrench adapter block.

4. The plug for blocking a heat transfer tube of a heat exchanger according to claim 2, characterized in that: One end of the hexagonal wrench is connected to the hexagon socket screw via a wire retaining spring or a magnet.

5. The plug for blocking a heat transfer tube of a heat exchanger according to claim 1, characterized in that: The plug for plugging the heat transfer tube of the heat exchanger also includes a conical ferrule; The conical sleeve is sleeved on the other end of the screw to form a conical structure.

6. The plug for blocking a heat transfer tube of a heat exchanger according to claim 1, characterized in that: The other end of the pin extending out of the eccentric through hole is provided with a baffle.

7. The plug for blocking a heat transfer tube of a heat exchanger according to claim 1, characterized in that: The outer side surface of the cam and the outer side surface of the body close to one end of the cam are provided with knurling.

8. The plug for blocking a heat transfer tube of a heat exchanger according to claim 7, characterized in that: The knurling formed on the outer side surface of the cam and the outer side surface of the body close to one end of the cam is circumferential or axial knurling.

9. The plug for blocking a heat transfer tube of a heat exchanger according to claim 1, characterized in that: The outer side surface of the opening at the other end of the body is provided with knurling.

10. The plug for blocking a heat transfer tube of a heat exchanger according to claim 9, characterized in that: The outer side surface of the other end of the body is provided with circumferential knurling.

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