CN210805253U

CN210805253U - Optical centering device for hoisting top cover of pressure vessel of pressurized water reactor unit

Info

Publication number: CN210805253U
Application number: CN201920887699.6U
Authority: CN
Inventors: 陆少威
Original assignee: CNNC Nuclear Power Operation Management Co Ltd; Qinshan Nuclear Power Co Ltd
Current assignee: CNNC Nuclear Power Operation Management Co Ltd; Qinshan Nuclear Power Co Ltd
Priority date: 2019-06-13
Filing date: 2019-06-13
Publication date: 2020-06-19
Anticipated expiration: 2029-06-13

Abstract

The utility model belongs to the nuclear power station field of overhauing, concretely relates to an optics centering device that is used for pressurized water reactor unit pressure vessel top cap to hoist and mount. The device comprises a transmitting device, a receiving device and a calibration device. The receiving device comprises a target and a guide post, and the target is installed on the guide post. The central part of the hollow disc of the supporting seat is provided with threads; the emitter is arranged in the fixed sleeve, the fixed sleeve is fixedly connected with the supporting seat through a central thread, and the fixed sleeve is fastened through a locking nut; 6 adjusting screws penetrate through the fixing sleeve to adjust the coaxiality of the emitter and the supporting seat. The device saves a large amount of centering time, reduces the dosage of personnel, increases the visibility and the accuracy of centering operation, and ensures the safety of equipment.

Description

Optical centering device for hoisting top cover of pressure vessel of pressurized water reactor unit

Technical Field

The utility model belongs to the nuclear power station field of overhauing, concretely relates to an optics centering device that is used for pressurized water reactor unit pressure vessel top cap to hoist and mount.

Background

In a sealed metal housing. During the period of the pressurized water reactor unit refueling overhaul, the reactor top cover needs to be lifted from the reactor core to the top cover storage room so as to carry out nuclear fuel replacement. After the fuel is replaced, the top cover is lifted to the reactor core for reloading.

At present, when the top cover of the pressurized water reactor unit is installed again, the guide column installed on the bottom hole of the pressure container is used as a centering reference, and the pressurized water reactor unit is centered visually through a through hole of a flange of the top cover. Due to observation angle limitation, the centering mode needs to arrange personnel to perform auxiliary centering at the bottom of the refueling water pool, and at the moment, the reactor core is exposed and has extremely high radioactivity. Meanwhile, due to the limitation of a visual mode, centering needs to be performed right below the overhead hoisting, the operation is long in time consumption, and the high radiation environment dosage acceptance and the high industrial safety risk exist.

Taking the M310 reactor type as an example, the hoisting master command sends an instruction to a ring crane driver through an interphone, and the top cover is hoisted to the upper part of the reactor core from the top cover storage room. When the top cover is aligned with the guide post, the gap between the guide post and the through hole of the top cover needs to be observed for many times, and the position of the ring crane needs to be adjusted. Because the positions of the three guide columns need to be accurately centered, the hoisting command needs to be repeatedly observed to determine the position of the circular crane, and the centering time is long. Simultaneously because the top cap flange is thicker, personnel stand and can't see the guide post and get into the top cap through-hole above the pond, need arrange the staff at the bottom of the pool and observe, personnel expose the reactor core and have very big safety risk under the high radioactive environment this moment. Meanwhile, according to experience feedback, other power plants have an event similar to guide post scratching at present, and certain influence is caused on equipment safety and major maintenance lines.

Disclosure of Invention

Firstly, the purpose is as follows:

research and development is used for supplementary centering device of nuclear power plant pressurized water reactor unit pressure vessel top cap hoist and mount operation optical structure, can reduce the operation degree of difficulty of pressure vessel top cap hoist and mount operation, saves a large amount of centering and spends time, reduces personnel's dosage to increase the visuality, the accuracy of centering operation, in order to guarantee the security of equipment. Has important significance for the safety and the economic benefit of the nuclear power plant.

The technical scheme is as follows:

an optical centering device for hoisting a top cover of a pressure vessel of a pressurized water reactor unit comprises: the device comprises a transmitting device, a receiving device and a calibration device; the emitter comprises a lifting lug, a connector, a supporting seat, a bottom end cover, an emitter and a flange; the lifting lug is installed at the upper end of the connector through threaded connection, and the connector is connected to the supporting seat through a bolt; the receiving device comprises a target and a guide post, and the target is arranged on the guide post. The central part of the hollow disc of the supporting seat is provided with threads; the emitter is arranged in the fixed sleeve, the fixed sleeve is fixedly connected with the supporting seat through a central thread, and the fixed sleeve is fastened through a locking nut; 6 adjusting screws penetrate through the fixing sleeve to adjust the coaxiality of the emitter and the supporting seat.

The calibration device comprises a calibration cylinder body, a guide plate, a cross coordinate and a bottom plate; the calibration barrel body is of an integrated structure and is integrally a hollow cylinder; the guide plate is a disc, and the circle center part is provided with a center hole.

The center of the bottom plate is a cross coordinate.

The cross coordinate and the connecting line of the center hole of the guide plate are coaxial with the center line of the cylinder body of the calibration cylinder.

The bottom end cover is connected with the supporting seat through a long bolt, and the end cover wall of the bottom end cover is tightly contacted with the central inner wall of the flange; the center of the end cover of the bottom end cover is provided with a through hole, and the diameter of the through hole is the same as that of the emitter.

The flange is uniformly provided with annular through holes, and the diameter of the supporting seat is larger than the inner diameter of the through hole of the flange.

The connector is of a frame structure; the emitter is cylindrical, passes through the middle of the connector, passes through the fixed sleeve, and is positioned above the end cover at the bottom.

The guide posts are arranged on screw holes distributed in the pressure container in an annular mode according to a certain angle.

Thirdly, the effect is as follows:

the design method is successfully applied to the top cover reinstallation of Qinshan nuclear power Fangjiashan No. 1 and No. 2 units. Through the field use experience feedback, the device has good use effect, effectively shortens the top cover re-assembly centering time, generates economic benefit and improves the unit safety. The device ensures the accuracy and the safety of the centering of the top cover reinstallation operation and also reduces the personnel operation time in the high-radioactivity environment.

The invention has the following advantages:

1. the method is used for the top cover reinstallation of the pressure vessel of the pressurized water reactor nuclear power station.

2. Optical structure design, visual centering reduces the centering degree of difficulty.

3. Lightweight structural design, simple easy operation.

4. The target design, optics centering, hoist and mount centering precision are high.

5. The design of the centering precision calibration device can ensure the precision of the optical emitter.

6. Visual blind areas are eliminated, a water tank is omitted for centering observers, and the safety of hoisting operation is improved.

Drawings

FIG. 1 is a schematic view of an optical centering apparatus

FIG. 2 is a schematic diagram of a calibration cylinder in an optical pair

FIG. 3 top view of the optical centering device at the installation position

In the figure: 1. lifting lug, 2, connector, 3, bolt, 4, supporting seat, 5, bottom end cover, 6, emitter, 7, fixing sleeve, 8, adjusting screw, 9, locking nut, 10, top cover flange, 11, target, 12, guide column, 13, calibration cylinder body, 14, guide plate, 15, cross coordinate, 16 and bottom plate

Detailed Description

The device mainly comprises a transmitting device, a receiving device and a calibration device.

As shown in fig. 1, the lifting lug 1 is mounted on the support head 2 by means of a screw connection, and the support head 2 is connected to the bearing block 4 by means of bolts. The fixing sleeve 7 is connected with the supporting seat 4 through threads and is fastened through a locking nut 9. The emitter 6 is arranged in the fixing sleeve 7, and the coaxiality of the emitter and the supporting seat 4 can be adjusted by adjusting 6 adjusting screws 8 on the fixing sleeve 7. The bottom end cap 5 is connected to the support block 4 by means of a screw thread.

As shown in fig. 2, the target 11 is mounted on a guide post 12.

As shown in fig. 3, the calibration cylinder 13 is integrally processed, and the upper cylindrical surface of the cylinder is matched with the cylindrical surface of the support base 4 for positioning. The central cross coordinate 15 of the bottom plate 16 and the central hole connecting line of the guide plate 14 are coaxial with the central line of the calibration cylinder body 13 so as to ensure the centering precision.

The device is matched with a through hole of a top cover flange through the cylindrical surface of the supporting seat 4 so as to ensure the centering precision of the center of the through hole and the emitter 6.

The specific operation steps are as follows:

calibrating an optical centering device: the optical centering device is arranged on a calibration cylinder in the optical centering device, laser emitted by the emitter 6 is adjusted to pass through the guide plate 14 through the adjusting screw 8, and fine adjustment is carried out according to the position of the laser on the cross coordinate 15, so that the accuracy of the optical centering device is guaranteed.

The optical centering device is installed: one end of the long rope is connected with the optical centering device lifting lug 1. The maintainer steps on the top cap, inserts the optics centering device into the corresponding guide post through-hole of top cap flange 10 to fix the other end of the long rope on the top cap hoist. The target 11 is mounted on the upper screw hole of the guide post 12.

Auxiliary centering for hoisting of the top cover of the pressure vessel: the top cover is lifted above the reactor core, and the lifting main command can directly observe the relative position of the laser point emitted by the emitter 6 and the target 11 and align the centering position through adjustment. The top cover is slowly lowered until the guide posts 12 contact the lower end cap 5 and eject the laser emitting device from the through hole. And continuously descending the top cover to the position of the core.

Dismantling the optical centering device: the service man removes the laser emitting device from the top cover with a long rope.

Claims

1. An optical centering device for hoisting a top cover of a pressure vessel of a pressurized water reactor unit, comprising: the device comprises a transmitting device, a receiving device and a calibration device; the transmitting device comprises a lifting lug (1), a connector (2), a supporting seat (4), a bottom end cover (5), a transmitter (6) and a flange (10); the lifting lug (1) is installed at the upper end of the connector (2) through threaded connection, and the connector (2) is connected to the supporting seat (4) through a bolt (3); the receiving device comprises a target (11) and a guide column (12), wherein the target (11) is arranged on the guide column (12);

the method is characterized in that: the supporting seat (4) is a hollow disc, and the central part of the supporting seat is provided with threads; the emitter (6) is arranged in a fixed sleeve (7), the fixed sleeve (7) is fixedly connected with the supporting seat (4) through a central thread, and the fixed sleeve (7) is fastened through a locking nut (9); 6 adjusting screws (8) penetrate through the fixed sleeve (7) to adjust the coaxiality of the emitter (6) and the supporting seat (4).

2. The apparatus of claim 1, wherein: the calibration device comprises a calibration cylinder body (13), a guide plate (14), a cross coordinate (15) and a bottom plate (16); the calibration cylinder body (13) is of an integrated structure and is a hollow cylinder as a whole; the guide plate (14) is a disc, and the circle center part is provided with a central hole.

3. The apparatus of claim 2, wherein: the center of the bottom plate (16) is a cross coordinate (15).

4. The apparatus of claim 3, wherein: the connecting line of the cross coordinate (15) and the central hole of the guide plate (14) is coaxial with the central line of the calibration cylinder body (13).

5. The apparatus of claim 1, wherein: the bottom end cover (5) is connected with the supporting seat (4) through a long bolt, and the end cover wall of the bottom end cover (5) is tightly contacted with the central inner wall of the through hole of the flange (10); the center of the bottom end cover (5) is provided with a through hole, and the diameter of the through hole is the same as that of the emitter (6).

6. The apparatus of claim 5, wherein: the flange (10) is uniformly provided with annular through holes, and the diameter of the supporting seat (4) is larger than the inner diameter of the through holes of the flange (10).

7. The apparatus of claim 1, wherein: the connector (2) is of a frame structure; the emitter (6) is cylindrical, penetrates through the middle of the connector (2) and penetrates through the fixing sleeve (7), and the bottom of the emitter is positioned above the end cover (5).

8. The apparatus of claim 1, wherein: the guide posts (12) are arranged on screw holes which are distributed annularly on the pressure container according to a certain angle.