Valve position sensor with corrugated pipe cable joint

Abstract

The invention relates to the field of nuclear reactors, in particular to a valve position sensor with a corrugated pipe cable connector. The valve position sensor comprises an annular sensor, a corrugated pipe cable and an electrical plug which are sequentially connected to form an integrated structure, the tail end of the electrical plug is connected with an L-shaped fixing plate, and the cable is led out from a tail clamp of the electrical plug. The annular sensor, the corrugated pipe cable and the electrical plug are all of totally-enclosed metal structures. The integrated structure design is adopted, and work can be effectively carried out under the high-temperature, high-irradiation, strong-magnetism, earthquake and LOCA environments of the nuclear power plant.

Description

Technical Field

[0001] The invention relates to the field of nuclear reactors, and in particular to a valve position sensor with a bellows cable connector. Background Art

[0002] Important valves in nuclear power plants usually use Class 1E continuous valve displacement sensors to measure valve positions, and then use transmitters (secondary instruments) to convert valve position signals into standard analog signals and provide them to the main control room of the nuclear power plant so that operating personnel can monitor the valve opening at any time.

[0003] Class 1E valve position sensors used in nuclear power plants must be resistant to high temperatures, radiation, and strong magnetic interference. They must also ensure measurement accuracy within the long-distance signal transmission range and should be able to perform their specified functions under seismic loads and accident conditions such as LOCA.

[0004] The 1E-level valve position sensors used in domestic nuclear power plants have various structural forms, but there are still certain problems in terms of convenience of installation and maintenance, as well as usability. After measuring the valve position signal, the existing 1E-level valve position sensors in nuclear power plants pass through the electrical plug on the sensor, cable, junction box, and cable in sequence, penetrate the reactor containment, and transmit it to the transmitter in the electrical plant. After the transmitter converts the signal, it is transmitted to the main control room of the nuclear power plant to complete the valve position measurement of important valves. The above usage method has the following problems:

[0005] (1) The sensor coil, electrical connector, cable and junction box are not modular in design. During the transmission of the valve position signal, three connectors need to be connected: the sensor electrical connector and the cable, the cable and the junction box, and the junction box and the reserved cable at the rear end. The disassembly and connection are cumbersome in use;

[0006] (2) The signal input wiring and signal output wiring in the junction box must be connected using special tools, and after installation and disassembly, they cannot be directly connected and used again, and the sealing in the LOCA accident environment cannot be guaranteed, that is, the original wiring in the junction box cannot be reused;

[0007] (3) In the process of transmitting the on-site valve position signal to the transmitter, especially from the sensor to the reactor containment, there are many connection joints and rubber cables are usually used, which are susceptible to strong magnetic interference, affecting the signal transmission amplitude and measurement accuracy. Summary of the invention

[0008] The technical problem to be solved by the present invention is to provide a valve position sensor with a bellows cable connector, which adopts an integrated structural design and can effectively work in the high temperature, high radiation, strong magnetism, earthquake and LOCA environment of a nuclear power plant.

[0009] The present invention provides a valve position sensor with a bellows cable connector, comprising:

[0010] The ring sensor, corrugated tube cable, and electrical connector are connected in sequence to form an integrated structure.

[0011] The end of the electrical connector is connected to an L-shaped fixing plate.

[0012] The cable is led out from the tail clip of the electrical plug;

[0013] The annular sensor, corrugated tube cable and electrical connector are all fully enclosed metal structures.

[0014] In a specific embodiment of the present invention, a threaded joint is provided on one side of the annular sensor, and the threaded joint is connected to a first movable nut at one end of the corrugated tube cable;

[0015] The second movable nut at the other end of the corrugated tube cable is connected to the electrical connector.

[0016] In a specific embodiment of the present invention, the electrical connector includes a plug of an electrical connector and a socket of an electrical connector;

[0017] The plug of the electrical appliance plug and the socket of the electrical plug are connected by a snap-fit;

[0018] The second movable nut at the other end of the corrugated tube cable is connected to the plug of the electrical connector.

[0019] In a specific embodiment of the present invention, the annular sensor is composed of a threaded joint, a housing, a coil, a skeleton bottom plate and a skeleton body that are welded together;

[0020] The skeleton bottom plate and the skeleton body are welded to form a skeleton, and the coil is wound on the skeleton; the outer shell and the skeleton are closed by welding, and the lead wire of the coil passes through the threaded joint and a certain length is reserved to facilitate the cable connection with the corrugated tube cable.

[0021] In a specific embodiment of the present invention, the sealing method of the annular sensor is:

[0022] Through the inner hole of the threaded joint, epoxy resin is poured to seal and fix the coil;

[0023] After the resin is formed, connect the wires leading out of the coil to the cables in the corrugated tube cable according to the wiring requirements, and then install the insulating heat shrink tubing to complete the cable connection;

[0024] Fill the inner hole of the threaded joint with epoxy resin again to seal and fix the butt joint;

[0025] After waiting for the resin to be molded, fill the first movable nut at one end of the corrugated tube cable with a heat-resistant and radiation-resistant sealing gasket and connect it to the threaded joint;

[0026] Laser welding is used to weld the first movable nut in one circle after the connection is completed.

[0027] In a specific embodiment of the present invention, the socket of the electrical plug has an L-shaped fixing plate.

[0028] In a specific embodiment of the present invention, the cable is led out from a tail clip of a socket of an electrical plug.

[0029] Compared with the prior art, the valve position sensor with a bellows cable connector of the present invention has the following beneficial effects:

[0030] (1) The integrated valve position sensor with a bellows cable connector no longer has an electrical connector installed on the sensor, and the junction box is eliminated; the cable from the sensor to the rear end of the original junction box has only one electrical connector, which facilitates on-site maintenance of the valve position sensor in nuclear power plants;

[0031] (2) The structural design of the L-shaped electrical socket and the annular sensor enables quick connection and disassembly of the valve position sensor;

[0032] (3) It is resistant to temperature, radiation, and strong magnetic interference, and can perform the specified functions under earthquake and LOCA conditions. It is especially suitable for use on valves in nuclear power plants. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] Figure 1 A block diagram of a bellows cable connector valve position sensor system;

[0034] Figure 2 This is the structural diagram of the ring sensor;

[0035] Figure 3 This is a schematic diagram of the installation, debugging and use of the ring sensor;

[0036] In the figure, 1. annular sensor, 2. threaded joint, 3. first movable nut 1, 4. corrugated tube cable, 5. second movable nut, 6. plug of electrical connector, 7. socket of electrical connector, 8. L-shaped fixing plate, 9. socket tail clip, 10. housing, 11. coil, 12. skeleton bottom plate, 13. skeleton body, 14. front end face flange, 15. adjustment gasket, 16. core rod, 17. retaining ring, 18. rear end face flange. DETAILED DESCRIPTION

[0037] In order to further understand the present invention, the embodiments of the present invention are described below in conjunction with examples, but it should be understood that these descriptions are only for further illustrating the features and advantages of the present invention, rather than limiting the present invention.

[0038] The embodiment of the present invention discloses a valve position sensor with a bellows cable connector, such as Figure 1As shown, including:

[0039] The ring sensor 1, the corrugated tube cable 4, and the electrical connector are connected in sequence to form an integrated structure.

[0040] A threaded joint 2 is provided on one side of the annular sensor 1, and the threaded joint 2 is connected to a first movable nut 3 at one end of a corrugated tube cable 4;

[0041] The electrical connector includes an electrical connector plug 6 and an electrical connector socket 7;

[0042] The plug 6 of the electrical connector and the socket 7 of the electrical connector are connected by a snap-fit ​​connection; the snap-fit ​​connection can be quickly locked and separated;

[0043] The second movable nut 5 at the other end of the corrugated tube cable 4 is connected to the plug 6 of the electrical connector.

[0044] The socket 7 of the electrical plug is provided with an L-shaped fixing plate 8; the L-shaped fixing plate 8 can fix the corrugated pipe cable on the ground or on the wall, thus saving installation space and simplifying the connection and disassembly procedures of the valve position sensor;

[0045] The cable is led out from the tail clip 9 of the socket 7 of the electrical plug and connected to the electrical penetration piece of the reactor containment of the nuclear power plant.

[0046] The annular sensor 1, the corrugated tube cable 4 and the electrical connector are all fully enclosed metal structures.

[0047] like Figure 2 As shown, the annular sensor 1 is composed of a threaded joint 2, a housing 10, a coil 11, a skeleton bottom plate 12 and a skeleton body 13 which are welded together;

[0048] The frame bottom plate 12 and the frame body 13 are welded to form a frame, and the coil 11 is wound on the frame. The housing 10 and the frame are sealed by welding, and the lead wire of the coil 11 passes through the threaded connector 2 and a certain length is reserved to facilitate the cable connection with the corrugated tube cable 4.

[0049] The sealing method of the annular sensor 1 is:

[0050] The coil is sealed and fixed by pouring epoxy resin through the inner hole of the threaded joint 2;

[0051] After waiting for the resin to be formed, the wires leading out of the coil are connected to the cables in the corrugated tube cable 4 according to the wiring requirements, and then the insulating heat shrink sleeve is installed to complete the cable connection;

[0052] Fill the inner hole of the threaded joint 2 with epoxy resin again to seal and fix the butt joint;

[0053] After waiting for the resin to be molded, a heat-resistant and radiation-resistant sealing gasket is filled in the first movable nut 3 at one end of the corrugated tube cable 4 and then connected to the threaded joint 2;

[0054] The first movable nut 2 after the connection is completed is welded in one circle by laser welding.

[0055] When the valve position sensor with a bellows cable connector of the present invention is used,

[0056] The annular sensor 1 of the valve position sensor with a bellows cable connector is mounted on the outside of a metal body with an iron core rod inside. When the iron core inside the metal body and the valve stem move as a whole, displacement is generated, and a displacement signal is output through the valve position sensor with a bellows cable connector.

[0057] Specifically, Figure 3 As shown, the annular sensor 1 with the corrugated tube cable 4 is mounted on the outside of the body of the front face flange 14 with the core rod 16 inside. The rear face flange 18 is clamped on the rear of the annular sensor 1, and the screw rod passes through the threaded holes of the two flanges to fix the annular sensor 1. The initial installation displacement zero point is adjusted by a number of adjustment gaskets 15 with thicknesses of 0.1 to 0.5 mm to meet the installation measurement requirements.

[0058] When installing, debugging and repairing the whole set of bellows cable connector valve position sensor, the screw passing through the flange can be loosened, and the annular sensor 1 can rotate 360° around the circular body of the front face flange 14. The retaining ring 17 is installed outside the rear face flange 18, which can effectively prevent the rear face flange 18 from falling after the screw is loosened.

[0059] After completing all the above work, install the L-shaped fixing plate 8 on the socket 7 of the electrical plug on the wall near the bellows cable connector valve position sensor with 4 screws to achieve quick connection and disassembly of the bellows cable connector valve position sensor.

[0060] The above embodiments are only used to help understand the method and core idea of ​​the present invention. It should be noted that, for those skilled in the art, several improvements and modifications can be made to the present invention without departing from the principles of the present invention, and these improvements and modifications also fall within the scope of protection of the claims of the present invention.

[0061] The above description of the disclosed embodiments enables one skilled in the art to implement or use the present invention. Various modifications to these embodiments will be apparent to one skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the present invention. Therefore, the present invention will not be limited to the embodiments shown herein, but rather to the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A valve position sensor with a bellows cable connector, characterized in that: include: The ring sensor, corrugated tube cable, and electrical connector are connected in sequence to form an integrated structure. The end of the electrical connector is connected to an L-shaped fixing plate. The cable is led out from the tail clip of the electrical plug; The annular sensor, corrugated tube cable and electrical connector are all fully enclosed metal structures.

2. The valve position sensor with a bellows cable connector according to claim 1, characterized in that: A threaded joint is provided on one side of the annular sensor, and the threaded joint is connected to a first movable nut at one end of the corrugated tube cable; The second movable nut at the other end of the corrugated tube cable is connected to the electrical connector.

3. The valve position sensor with a bellows cable connector according to claim 2, characterized in that: The electrical connector includes a plug of the electrical connector and a socket of the electrical connector; The plug of the electrical appliance plug and the socket of the electrical plug are connected by a snap-fit; The second movable nut at the other end of the corrugated tube cable is connected to the plug of the electrical connector.

4. The valve position sensor with a bellows cable connector according to claim 1, characterized in that: The annular sensor is composed of a threaded joint, a housing, a coil, a frame bottom plate and a frame body that are welded together; The skeleton bottom plate and the skeleton body are welded to form a skeleton, and the coil is wound on the skeleton; the outer shell and the skeleton are closed by welding, and the lead wire of the coil passes through the threaded joint and a certain length is reserved to facilitate the cable connection with the corrugated tube cable.

5. The valve position sensor with a bellows cable connector according to claim 2, characterized in that: The sealing method of the annular sensor is: Through the inner hole of the threaded joint, epoxy resin is poured to seal and fix the coil; After the resin is formed, connect the wires leading out of the coil to the cables in the corrugated tube cable according to the wiring requirements, and then install the insulating heat shrink tubing to complete the cable connection; Fill the inner hole of the threaded joint with epoxy resin again to seal and fix the butt joint; After waiting for the resin to be molded, fill the first movable nut at one end of the corrugated tube cable with a heat-resistant and radiation-resistant sealing gasket and connect it to the threaded joint; Laser welding is used to weld the first movable nut in one circle after the connection is completed.

6. The valve position sensor with a bellows cable connector according to claim 2, characterized in that: The socket of the electrical plug is provided with an L-shaped fixing plate.

7. The valve position sensor with a bellows cable connector according to claim 2, characterized in that: The cable is led out from a rear clip of a socket of an electrical plug.

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