An automatic sealing device for small-diameter pipes

Abstract

This invention provides an automatic sealing device for small-diameter pipes, comprising a power output component, a transmission component, and a sliding sealing component. One transmission element of the transmission component is fixedly connected to the sliding sealing component. The sliding sealing component has a bushing, a threaded sliding sleeve, a sealing seat, and a sealing ring. The sealing seat is fitted onto the outside of a nylon pipe, and its outer wall has a threaded mating surface for threaded connection to the threaded sliding sleeve. The inner wall of the left end of the sealing seat has an inner sliding mating surface, within which the sealing ring is disposed. The bushing is inserted into the sliding mating surface. Driven by the transmission component, the threaded sliding sleeve rotates, pushing the bushing to compress the sealing ring. This invention enables automated sealing of small-diameter pipes, eliminating the need for manual operation and reducing radiation dose to workers.

Description

Technical Field

[0001] This invention relates to the field of nuclear power plant reactor pressure vessel maintenance technology, and in particular to an automatic sealing device for small-diameter pipes. Background Technology

[0002] During the chemical cleaning of the reactor neutron flux tube, a nylon tube is inserted into the neutron flux tube and the cleaning medium is injected. During the process, the outer wall of the nylon tube at the return port and the connection joint of the neutron flux tube need to be sealed to prevent leakage of the cleaning medium.

[0003] The original sealing structure of the nylon tube is as follows Figure 1 As shown, the sealing structure mainly consists of a locking nut 14, a clamping block 15, and an O-ring 16.

[0004] The current operating procedure involves manually tightening the locking nut 14 clockwise when a seal is required on the nylon tube. The locking nut 14 pushes the clamping block 15, which in turn compresses and deforms the O-ring 16, thus forming a seal between the outer wall of the nylon tube 1 and the connecting joint 17. Because neutron flux tube cleaning involves high radioactivity, the locking and releasing of the seals needs to be performed frequently. During manual operation, personnel are exposed to radiation. Furthermore, the uneven force applied during manual operation can lead to leakage of the cleaning medium, potentially releasing radioactive products into the work environment, causing pollution and increased environmental dose. Summary of the Invention

[0005] The purpose of this invention is to overcome the defects described in the prior art and provide an automatic sealing device for small-diameter pipes. This sealing device can realize the automated operation of sealing small-diameter pipes without manual operation, thereby reducing the radiation dose to operators and reducing pollution and environmental dose.

[0006] To achieve the above objectives, the present invention provides the following technical solution:

[0007] An automatic sealing device for small-diameter pipes includes a power output component, a transmission component, and a sliding sealing component. A transmission component of the transmission component is fixedly connected to the sliding sealing component. The sliding sealing component has a bushing, a threaded sliding sleeve, a sealing seat, and a sealing ring. The sealing seat is sleeved on the outside of the nylon pipe. The outer wall of the sealing seat has a threaded mating surface for threaded connection with the threaded sliding sleeve. The inner wall of the left end of the sealing seat has an inner sliding mating surface. The sealing ring is disposed within the inner sliding mating surface. The bushing is inserted into the sliding mating surface. Under the drive of the transmission component, the threaded sliding sleeve rotates and pushes the bushing to compress the sealing ring.

[0008] As one possible implementation, a conical surface is provided at the junction of the nylon tube perforation of the sealing seat and the inner sliding mating surface, and the sealing ring is placed on the conical surface.

[0009] As one feasible approach, the left side of the outer wall of the sealing seat is the threaded mating surface, and the right side is the external sliding mating surface. The left side of the inner wall of the threaded sleeve is provided with an internal thread of the threaded sleeve that is adapted to the threaded mating surface, and the right side of the inner wall is provided with a threaded sleeve sliding surface that is adapted to the external sliding mating surface, so that the threaded sleeve can rotate and slide on the sealing seat.

[0010] As one possible implementation, the bushing has a shoulder abutting against the inner side of the end of the threaded sleeve, and the bushing is provided with an elastic retaining ring abutting against the outer side of the end of the threaded sleeve, so that the bushing is pushed to move axially when the threaded sleeve rotates.

[0011] As one possible implementation, the power output component is a geared motor, and the transmission component is a gear transmission component.

[0012] In one possible implementation, the gear transmission assembly includes a large gear, a small gear, a bushing, and a mounting base. The geared motor is mounted on the mounting base, the bushing is mounted on the output shaft of the geared motor, the small gear is mounted on the bushing, the small gear meshes with the large gear, and the large gear is mounted on the threaded sleeve.

[0013] As one possible approach, the housing is fixed to the mounting base.

[0014] As one possible implementation, the power output component is a servo motor, tubular motor, pneumatic device, hydraulic device, or electromagnetic device.

[0015] As one feasible approach, one end of the tee assembly is threaded to the sealing seat.

[0016] Compared with the prior art, the automatic sealing device for small-diameter pipes provided by the present invention has the following advantages:

[0017] This invention enables automated sealing of small-diameter pipes, eliminating the need for manual operation and reducing radiation dose to workers.

[0018] The present invention provides a uniform and adjustable locking force, avoiding the risk of media leakage caused by uneven tightening force due to manual operation of the locking nut.

[0019] This invention is a component of a complete set of automated devices for neutron flux tubes, serving the entire automated system. Attached Figure Description

[0020] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0021] Figure 1 A schematic diagram of the original sealing structure of the nylon tube provided by the existing technology;

[0022] Figure 2 This is a schematic diagram of the automatic sealing device for small-diameter pipes provided by the present invention.

[0023] Figure 3 for Figure 2 Enlarged view of point A in the middle.

[0024] Explanation of reference numerals in the attached figures:

[0025] 1-Nylon tube, 2-Bushing, 3-Threaded sleeve, 4-Sealing seat, 5-Large gear, 6-Tee connector assembly, 7-Elastic retaining ring, 8-Sealing ring, 9-Cover, 10-Pin gear, 11-Shaft sleeve, 12-Mounting base, 13-Geared motor; 14-Locking nut, 15-Pressure block, 16-O-ring seal, 17-Connecting joint. Detailed Implementation

[0026] The following detailed description provides further details on specific implementation methods.

[0027] like Figure 2 and 3 As shown, the present invention provides an automatic sealing device for small-diameter pipes. The main body of the device includes a power output component, a transmission component, and a sliding sealing component. The entire device is connected to the neutron flux tube through a three-way connector component 6, and the sealing of the outer wall of the nylon tube 1 is achieved at the sealing ring 8.

[0028] The power output component preferably uses a geared motor 13 as the power source (e.g., Figure 2 (As shown), other motors such as servo motors and tubular motors, or pneumatic devices, hydraulic devices, electromagnetic devices, etc., can also be used to achieve sealed power output.

[0029] The small-diameter pipe automatic sealing device is connected to the control system via PLC. According to the cleaning function requirements, the program automatically controls the operation, stop, forward and reverse rotation of the reduction motor 13, which drives the transmission component and the sliding sealing component to achieve automatic sealing and release of the nylon pipe.

[0030] The transmission assembly includes a large gear 5, a small gear 10, a bushing 11, and a mounting base 12. The geared motor 13 is mounted on the mounting base 12, the bushing 11 is mounted on the output shaft of the geared motor 13, and the small gear 10 is mounted on the bushing 11, meshing with the large gear 5. The large gear 5 is mounted on a threaded sliding sleeve 3. The connections of these components can be made using locking screws, interference fits, keyways, splines, threads, and sealant.

[0031] The sliding sealing assembly includes a bushing 2, a threaded sliding sleeve 3, a sealing seat 4, an elastic retaining ring 7, and a sealing ring 8. The tee fitting assembly 6 is threadedly connected to the sealing seat 4, and the sealing seat 4 is fixed to the mounting base 12. The outer wall of the sealing seat 4 is segmented, providing an external sliding mating surface and a threaded mating surface. Figure 3 In this structure, the left side of the outer ring surface of the threaded sleeve 3 is a threaded mating surface, and the right side is a smooth sliding mating surface. It engages with the threaded sleeve 3, which has the same structure, for transmission. That is, the left side of the inner wall of the threaded sleeve 3 is provided with an internal thread that matches the threaded mating surface, and the right side of the inner wall is provided with a sliding surface that matches the external sliding mating surface. This enables the threaded sleeve 3 to rotate and slide on the sealing seat 4. In other words, the meshing of the large and small gears drives the threaded sleeve 3 to rotate forward and backward along the thread direction, realizing the forward and backward movement of the threaded sleeve 3 on the sealing seat 4. This transmission structure has a self-locking function. That is, the entire sealing transmission is achieved through three methods: a reduction motor, gears, and threads. The motor drives the gears, the gears drive the threads, and the axial movement of the threaded sleeve drives the axial movement of the bushing, thereby realizing the compression and release of the bushing on the sealing ring 8. The self-locking function means that under the drive of the reduction motor, the bushing can stay in the sealed or loose position. At this position, the position of the reduction motor is locked, and the threaded sleeve cannot rotate. That is, it is locked at this position, realizing self-locking.

[0032] like Figure 2 As shown, the sealing seat 4 is a hollow structure, fitted onto the nylon tube 1. The inner bore of the sealing seat 4 comprises two sections: an inner sliding mating surface on the left and a nylon tube perforation on the right. The junction of the inner sliding mating surface and the nylon tube perforation is a conical surface. The inner sliding mating surface mates with the right end of the bushing 2, and the bushing 2 is inserted into the inner sliding mating surface, enabling relative sliding between the bushing 2 and the sealing seat 4. The threaded sliding sleeve 3 rotates to the right, pushing the bushing 2 to slide to the right; the threaded sliding sleeve 3 can slide left and right. The nylon tube perforation inside the sealing seat 4 ensures the smooth passage of the nylon tube 1 while effectively limiting excessive radial deformation of the nylon tube 1.

[0033] The bushing 2 is axially fixed to the threaded sleeve 3 via its own shoulder and the elastic retaining ring 7. The bushing 2 is clamped on both sides of the threaded sleeve 3 via the shoulder and the elastic retaining ring 7. The bushing 2 and the threaded sleeve 3 are axially fixed by the combined action of the spring retaining ring 7 and its own shoulder, but not circumferentially. When the threaded sleeve 3 slides on the sealing seat 4, it drives the bushing 2 to slide linearly, thereby pressing or releasing the sealing ring 8. The inner diameter of the sealing ring 8 is slightly larger than the outer diameter of the nylon tube 1. When the bushing 2 presses against the sealing ring 8, the sealing ring 8 is deformed by compression. At this time, the sealing ring 8 is tightly fitted to the outer wall of the nylon tube 1, the conical surface of the sealing seat 4, and the end face of the bushing 2 (e.g., ...). Figure 3 As shown in the figure, a compression seal is formed at these three points to achieve a seal on the outer wall of the nylon tube 1.

[0034] like Figure 2 As shown, the large gear 5 is fixed on the threaded sleeve 3, and the small gear 10 is fixed on the output shaft of the geared motor 13 through the bushing 11. The geared motor 13 is fixed on the mounting base 12. The small gear 10 is wider than the large gear 5 to ensure that the large gear 5 always meshes with the small gear 10 when it drives the threaded sleeve 3 to move within the working stroke.

[0035] The cover 9 is fixed on the mounting base 12 to protect the transmission mechanism.

[0036] This invention employs gear and thread transmission, but can also use worm gear transmission, connecting rod transmission, and other transmission methods.

[0037] The sealing process of the small-diameter pipe automatic sealing device of the present invention is as follows:

[0038] When the geared motor 13 is powered on, the device is in a desealed state: the bushing 2 (threaded sliding sleeve 3, large gear 5) is in the left limit working position, and the sealing ring 8 is not compressed or deformed;

[0039] Insert the nylon tube 1 into the device and extend it to the bottom of the neutron flux tube;

[0040] Start the geared motor 13 and rotate it clockwise: At this time, the small gear 10 rotates clockwise, and the large gear 5 meshing with it drives the threaded sleeve 3 to rotate counterclockwise and move to the right. That is, the large gear 5 and the threaded sleeve 3 are fixed. The rotation of the large gear 5 will drive the threaded sleeve 3 to move axially, and thus it will also move axially. At the same time, the threaded sleeve 3 drives the bushing 2 to move synchronously to the right until the sealing ring 8 is pressed against the conical surface of the sealing seat 4.

[0041] The inner diameter of the sealing ring 8 is reduced by compression, and it fits tightly against the outer wall of the capillary tube 1, thus completing the seal on the outer wall of the capillary tube.

[0042] Similarly, the counterclockwise rotation of the geared motor 13 is the process of the automatic sealing device for small-diameter pipes releasing the seal.

[0043] Therefore, this invention achieves automatic sealing of the outer wall of the nylon tube during the chemical cleaning process of the neutron flux tube. When the seal is released by a motor, the nylon tube is in an unsealed state and can move freely axially under external force; when the seal is applied by a motor, the nylon tube is in a sealed state and is fixed axially.

[0044] This invention can seal gas, water or other fluid media.

[0045] This invention can seal the outer wall of pipes made of materials other than nylon, such as steel pipes, aluminum pipes, and copper pipes.

[0046] This invention employs threaded transmission to ensure that the original reliable sealing state can still be maintained even in the event of external power failure.

[0047] This invention can achieve sealing of the outer wall of pipes of different diameters by changing the size of the sealing ring and related mating parts.

[0048] This invention features a lightweight design and a compact structure. The structural design of the power unit, transmission components, and sealing components should be protected.

[0049] The above description is merely a specific embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in the present invention should be included within the scope of protection of the present invention. Therefore, the scope of protection of the present invention should be determined by the scope of the claims.

Claims

1. An automatic sealing device for small-diameter pipes, characterized in that, The device includes a power output assembly, a transmission assembly, and a sliding sealing assembly. One transmission component of the transmission assembly is fixedly connected to the sliding sealing assembly. The sliding sealing assembly has a bushing (2), a threaded sliding sleeve (3), a sealing seat (4), and a sealing ring (8). The sealing seat (4) is fitted onto the outside of the nylon tube (1). The outer wall of the sealing seat (4) has a threaded mating surface for threaded connection to the threaded sliding sleeve (3). The inner wall of the left end of the sealing seat (4) has an inner sliding mating surface. The sealing ring (8) is disposed in the inner sliding mating surface. The bushing (2) is inserted into the sliding mating surface. The threaded sliding sleeve (3) rotates under the drive of the transmission assembly, pushing the bushing (2) to squeeze the sealing ring (8).

2. The automatic sealing device for small-diameter pipes according to claim 1, characterized in that, The junction of the nylon tube perforation of the sealing seat (4) and the inner sliding mating surface is provided with a conical surface, and the sealing ring (8) is placed on the conical surface.

3. The automatic sealing device for small-diameter pipes according to claim 1, characterized in that, The outer wall of the sealing seat (4) has a threaded mating surface on the left and an outer sliding mating surface on the right. The inner wall of the threaded sleeve (3) has an internal thread that matches the threaded mating surface on the left and a sliding surface that matches the outer sliding mating surface on the right, so that the threaded sleeve (3) can rotate and slide on the sealing seat (4).

4. The automatic sealing device for small-diameter pipes according to claim 1, characterized in that, The bushing (2) has a shoulder that abuts against the inner side of the end of the threaded sleeve (3). The bushing (2) is provided with an elastic retaining ring (7) that abuts against the outer side of the end of the threaded sleeve (3) so that the threaded sleeve (3) can push the bushing (2) to move axially when it rotates.

5. The automatic sealing device for small-diameter pipes according to claim 1, characterized in that, The power output component is a geared motor (13), and the transmission component is a gear transmission component.

6. The automatic sealing device for small-diameter pipes according to claim 5, characterized in that, The gear transmission assembly includes a large gear (5), a small gear (10), a bushing (11), and a mounting base (12). The geared motor (13) is mounted on the mounting base (12), the bushing (11) is mounted on the output shaft of the geared motor (13), the small gear (10) is mounted on the bushing (11), the small gear (10) meshes with the large gear (5), and the large gear (5) is mounted on the threaded sliding sleeve (3).

7. The automatic sealing device for small-diameter pipes according to claim 6, characterized in that, The cover (9) is fixed on the mounting base (12).

8. The automatic sealing device for small-diameter pipes according to claim 1, characterized in that, The power output component is a servo motor, tubular motor, pneumatic device, hydraulic device, or electromagnetic device.

9. The automatic sealing device for small-diameter pipes according to claim 1, characterized in that, One end of the tee connector assembly (6) is threaded to the sealing seat (4).

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