阅读说明：本技术 一种核岛引漏环在线更换装置及更换方法 (Nuclear island leakage leading ring online replacing device and replacing method ) 是由 陈宝成 李攀攀 张小辉 韩鹏 周晓明 金泽 王浩 于 2019-11-14 设计创作，主要内容包括：本发明涉及核电用电动阀门技术领域,具体公开了一种核岛引漏环在线更换装置及更换方法,其中装置包括引漏环切割装置、内环取出装置及外环取出装置；采用引漏环切割装置将中间填料引漏环切割成内环和外环两部分,采用内环取出装置将引漏环内环取出,采用外环取出装置将引漏环外环取出,最后将新引漏环安装于阀杆上。本发明引漏环取出装置结构设计科学合理,适用于狭窄空间内的核岛电动闸阀引漏环的取出,具有易于操作、取出速度快、避免核泄露的优点。(The invention relates to the technical field of electric valves for nuclear power, and particularly discloses an online replacement device and a replacement method for a nuclear island leakage leading ring, wherein the device comprises a leakage leading ring cutting device, an inner ring taking-out device and an outer ring taking-out device; and cutting the middle filler leakage guide ring into an inner ring and an outer ring by adopting a leakage guide ring cutting device, taking out the inner ring of the leakage guide ring by adopting an inner ring taking-out device, taking out the outer ring of the leakage guide ring by adopting an outer ring taking-out device, and finally installing a new leakage guide ring on the valve rod. The leakage guide ring taking-out device is scientific and reasonable in structural design, is suitable for taking out the leakage guide ring of the nuclear island electric gate valve in a narrow space, and has the advantages of easiness in operation, high taking-out speed and nuclear leakage prevention.)

1. The utility model provides a nuclear island draws online change device of hourglass ring which characterized in that: comprises a leakage guide ring cutting device, an inner ring taking-out device and an outer ring taking-out device;

the leakage-leading ring cutting device comprises a base (1), a stuffing box (2), a holding cylinder (3), a cantilever beam (4), an electric spark machine head (6), a machine head support (7), a cylindrical holding seat (8), a connecting frame (9), an insulating ring frame (11), a cylindrical electrode support (13), a valve rod protective sleeve (14) and two half cylindrical electrodes (16);

a stuffing box (2) is arranged at the center of the top of the base (1), and a holding cylinder (3) for containing heavy water is arranged on the outer side of the upper part of the base (1);

the bottom end of a valve rod (5) of the nuclear island electric gate valve is inserted into the stuffing box (2), and an upper stuffing sealing ring (27), a middle stuffing leakage guiding ring (17) and a lower stuffing sealing ring (18) which are arranged on the valve rod (5) are all positioned in the stuffing box (2);

the cylindrical embracing seat (8) is of an annular hoop structure and is arranged around the outer side of the upper part of the base (1) and below the embracing cylinder (3);

the machine head support (7) is fixedly arranged on the cylindrical embracing seat (8), and the electric spark machine head (6) is arranged on the machine head support (7) in an up-and-down moving manner;

the electric spark machine head (6) is connected with one end of the cantilever beam (4), an insulating ring frame (11) is vertically connected and installed below the other end of the cantilever beam (4) through a connecting frame (9), and the connecting frame (9) and the insulating ring frame (11) are fixed through a screw A (10);

two half-type cylindrical electrode supports (13) are coaxially arranged below the insulating ring frame (11) through screws B (12), and two half-type cylindrical electrodes (16) are coaxially arranged at the lower parts of the two half-type cylindrical electrode supports (13) through screws C (15);

when in use, the two half-type cylindrical electrodes (16) extend into the position of the middle filler leakage-leading ring (17);

the two half-type cylindrical electrodes (16) are made into a thin-wall cylindrical shape;

the two-half-cylinder-shaped electrode support (13) consists of a fixing ring (19) and two semi-cylinder-shaped support bodies (23), and a mounting table (22) is processed at the outer edge of the upper part of each of the two semi-cylinder-shaped support bodies (23);

the mounting table (22) is provided with a screw hole (21) fixedly mounted with the insulating ring frame (11), an annular groove is processed on the inner wall of the mounting table (22), a fixing ring (19) is embedded in the annular groove, and the fixing ring (19) is fixedly connected with the semi-cylindrical support body (23) by adopting a screw D (20) at intervals;

a working liquid inlet (24) is radially processed on the mounting platform (22) of one or two of the two semi-cylindrical support bodies (23), a through groove is axially processed on the outer side wall of the valve rod protective sleeve (14), and a working liquid flow passage (25) is enclosed by the outer side wall of the two semi-cylindrical electrode supports (13); the working liquid inlet (24) is communicated with the working liquid flow channel (25), and the working liquid flow channel (25) is continued to the outside of the two half-type cylindrical electrodes (16);

the two half-type cylindrical electrodes (16) are fixedly installed in a butt joint mode through radial screws (26) on the wall surface of the upper end;

in the cutting process of the leakage-leading ring, working liquid enters from a working liquid inlet (24), flows to a discharge gap of the two half-type cylindrical electrodes (16) along a working liquid flow passage (25), is forced to circulate, is discharged together with an electric corrosion product, is cooled by adopting an upper liquid flushing mode, and is led out to a circulating pump for recycling;

the inner ring taking-out device consists of a first pendulum bob (29), a clamping outer sleeve (30) and an inner clamping device (31), wherein the inner clamping device (31) consists of a cylindrical main body A (35) and a clamping jaw (37);

the cylindrical main body A (35) is assembled by two half-type structures, and is sleeved on a valve rod (5) of the electric gate valve of the nuclear island when in use, and a clamping jaw (37) is processed at the bottom of the cylindrical main body A (35);

the clamping jaws (37) are 4-8 in number and distributed at equal intervals, and elastic deformation can be carried out among the clamping jaws (37);

a clamping outer sleeve (30) is coaxially sleeved on the outer side of the lower part of the cylindrical main body A (35), and a first pendulum bob (29) is sleeved on the outer side of the cylindrical main body A (35) above the clamping outer sleeve (30);

the first pendulum bob (29) and the clamping outer sleeve (30) are respectively assembled by two half-type structures;

the outer ring taking-out device consists of a support cylinder (38), a second pendulum (39) and an outer clamping device (40), wherein the outer clamping device (40) consists of a cylindrical main body B (43) and a support claw (41);

the cylindrical main body B (43) is assembled by two half-type structures, and is sleeved on a valve rod (5) of the electric gate valve of the nuclear island when in use, and a supporting claw (41) is processed at the bottom of the cylindrical main body B (43);

the supporting claws (41) are claw-shaped with straight outer walls and widened bottom parts of inner walls;

the number of the supporting claws (41) is 4-8, the supporting claws are distributed at equal intervals, and the supporting claws (41) can elastically deform;

a support cylinder (38) is coaxially sleeved on the inner side of the cylindrical main body B (43), and a second pendulum bob (39) is sleeved at the upper part of the support cylinder (38) extending out of the cylindrical main body B (43);

the supporting cylinder (38) and the second pendulum bob (39) are respectively assembled by two half-type structures.

2. The on-line replacement device for the nuclear island leakage leading ring as claimed in claim 1, wherein: the insulating ring frame (11) is of a tile-shaped structure.

3. The on-line replacement device for the nuclear island leakage leading ring as claimed in claim 1, wherein: the cantilever beam (4), the connecting frame (9), the two half-type cylindrical electrode supports (13) and the two half-type cylindrical electrodes (16) are all made of conducting materials, and the insulating ring frame (11) is made of insulating materials, so that direct access of a positive electrode and a negative electrode is avoided.

4. The on-line replacement device for the nuclear island leakage leading ring as claimed in claim 1, wherein: and a valve rod protective sleeve (14) is coaxially sleeved in the two half-type cylindrical electrode supports (13).

5. The on-line replacement device for the nuclear island leakage leading ring as claimed in claim 1, wherein: and a thin-wall sleeve body (36) tightly pressed and sleeved on the outer side of the clamping jaw (37) is processed at the part of the clamping outer sleeve (30) contacted with the clamping jaw (37).

6. The on-line replacement device for the nuclear island leakage leading ring as claimed in claim 1, wherein: the bottom of the supporting cylinder (38) is provided with a bevel supporting part (42) which is tightly attached to the inner wall of the supporting claw (41).

7. An online replacement method of a nuclear island leakage leading ring by using the online replacement device according to any one of claims 1 to 6, characterized in that: the method comprises the following steps:

step 1: cutting of the leakage-leading ring

Cutting the middle filler leakage guide ring (17) into an inner ring (34) and an outer ring (33) by a leakage guide ring cutting device;

step 2: inner ring removal

An inner ring taking-out device is adopted to take out the inner ring (34) of the leakage guide ring;

and step 3: outer ring extraction

Taking out the outer ring (33) of the leakage guide ring by adopting an outer ring taking-out device;

and 4, step 4: replacement of leakage leading ring

A new leakage guide ring is arranged on the valve rod (5), the new leakage guide ring is composed of two half rings, two screw holes are respectively processed at two ends of a joint surface, and four inner hexagonal screws are used for fastening connection to form a standard complete circular ring.

8. The on-line replacement method of the nuclear island leakage leading ring as claimed in claim 7, wherein: in the step 1, the upper packing sealing ring (27) is taken down, and then a machine head support (7) of the leakage guide ring cutting device is fixedly arranged near one side of the valve rod (5) with the packing box (2); the two half-type cylindrical electrodes (16) are sleeved on the valve rod (5) through the cantilever beam (4), and the two half-type cylindrical electrodes (16) are moved to the upper part of the middle filler leakage guiding ring (17), so that the two half-type cylindrical electrodes (16) are positioned at the central position of the upper end surface of the middle filler leakage guiding ring (17); at the moment, a discharge surface is formed between the annular bottom surfaces of the two half-type cylindrical electrodes (16) and the intermediate filler leakage guide ring (17) to be cut, pits are formed on the intermediate filler leakage guide ring (17), the two half-type cylindrical electrodes (16) are controlled to move from top to bottom by using an electric spark control system, the intermediate filler leakage guide ring (17) is subjected to electric striking processing, and the intermediate filler leakage guide ring (17) is gradually cut into an inner ring (34) and an outer ring (33).

9. The on-line replacement method of the nuclear island leakage leading ring as claimed in claim 7, wherein: in the step 2, an inner ring taking-out device is used for clamping an inner ring (34), an inner clamping device (31) firstly extends into a position between the inner ring (34) and an outer ring (33), a clamping jaw (37) is clamped at the bottom of the inner ring (34), a clamping outer sleeve (30) is downwards wedged between the outer wall of the clamping jaw (37) and the inner wall of the outer ring (33) through a first pendulum (29), and therefore the inner clamping device (31) tightly clamps the inner ring (34), the inner ring taking-out device is lifted up in the vertical direction, and finally the inner ring (34) of the leakage guide ring is taken out.

10. The on-line replacement method of the nuclear island leakage leading ring as claimed in claim 7, wherein: in the step 3, the outer ring taking-out device is used for clamping the outer ring (33), the supporting claw (41) of the outer clamping device (40) is firstly inserted between the outer ring (33) of the leakage guide ring and the valve rod (5), the inclined supporting part (42) at the bottom of the supporting cylinder (38) is wedged into the supporting claw (41) to complete the clamping of the outer clamping device (40) and the outer ring (33), then the outer ring taking-out device is lifted up in the vertical direction, and finally the outer ring (33) of the leakage guide ring is taken out.

Technical Field

The invention belongs to the technical field of electric valves for nuclear power, and particularly relates to an online replacement device and a replacement method for a nuclear island leakage leading ring.

Background

Compared with the conventional electric valve for a large-scale thermal power station, the electric valve for nuclear power has higher technical characteristics and requirements. The nuclear island pressure boundary electric gate valve is one of key devices in a nuclear island, a valve rod sealing assembly of the nuclear island pressure boundary electric gate valve is shown in figure 1 and comprises an upper packing sealing ring 27, a middle packing leakage guide ring 17 and a lower packing sealing ring 18, and after the nuclear island pressure boundary electric gate valve is used for a long time, heavy water leaks from the lower packing sealing ring due to the fact that sealing quality is reduced, and finally the heavy water leaks. In order to avoid heavy water leakage, the upper and lower packing sealing rings need to be replaced regularly to ensure the normal and safe operation of the gate valve.

When the valve rod sealing assembly is replaced, the upper packing sealing ring 27, the middle packing leakage guide ring 17 and the lower packing sealing ring 18 are sequentially taken out in sequence. The problem that exists at present is that middle packing drainage ring 17 blocks with the packing box cavity inner wall, can not take out it according to conventional operating rules, and then leads to the unable change lower floor's packing. Therefore, how to take out and replace the intermediate packing leakage guide ring 17 in time as soon as possible in the production field becomes a bottleneck problem of maintenance work of the nuclear island pressure boundary electric gate valve.

In order to solve the above problems and avoid the leakage of heavy water, it is necessary to design an online replacement device and replacement method for the leakage guide ring.

Disclosure of Invention

The invention aims to provide an online replacement device and a replacement method for a nuclear island leakage leading ring, which are used for completely replacing the nuclear island leakage leading ring.

The technical scheme of the invention is as follows:

an online replacement device for a nuclear island leakage leading ring comprises a leakage leading ring cutting device, an inner ring taking-out device and an outer ring taking-out device;

the leakage-leading ring cutting device comprises a base, a stuffing box, a holding cylinder, a cantilever beam, an electric spark machine head, a machine head support, a cylindrical holding seat, a connecting frame, an insulating ring frame, a cylindrical electrode support, a valve rod protective sleeve and two half cylindrical electrodes;

a stuffing box is arranged at the center of the top of the base, and a holding cylinder for containing heavy water is arranged on the outer side of the upper part of the base;

the bottom end of a valve rod of the nuclear island electric gate valve is inserted into the stuffing box, and an upper stuffing sealing ring, a middle stuffing leakage-leading ring and a lower stuffing sealing ring which are arranged on the valve rod are all positioned in the stuffing box;

the cylindrical embracing seat is of an annular hoop structure and is arranged around the outer side of the upper part of the base and below the embracing cylinder;

the machine head bracket is fixedly arranged on the cylindrical embracing seat, and the electric spark machine head is arranged on the machine head bracket in an up-and-down moving manner;

the electric spark machine head is connected with one end of the cantilever beam, an insulating ring frame is vertically connected and installed below the other end of the cantilever beam through a connecting frame, and the connecting frame and the insulating ring frame are fixed through a screw A;

two half-type cylindrical electrode supports are coaxially arranged below the insulating ring frame through screws B, and two half-type cylindrical electrodes are coaxially arranged at the lower parts of the two half-type cylindrical electrode supports through screws C;

when in use, the two half-type cylindrical electrodes extend into the position of the middle filler leakage-leading ring;

the two half-type cylindrical electrodes are made into a thin-wall cylinder shape;

the two-half cylindrical electrode support consists of a fixing ring and two semi-cylindrical support bodies, and a mounting table is processed at the outer edge of the upper part of each of the two semi-cylindrical support bodies;

the mounting table is provided with a screw hole fixedly mounted with the insulating ring frame, the inner wall of the mounting table is provided with an annular groove, a fixing ring is embedded in the annular groove, and the fixing ring is fixedly connected with the semi-cylindrical support body by adopting a spaced screw D;

a working liquid inlet is formed in the mounting table of one or two of the two semi-cylindrical support bodies along the radial direction, a through groove is formed in the outer side wall of the valve rod protective sleeve along the axial direction, and a working liquid flow channel is formed by the through groove and the inner side wall of the two semi-cylindrical electrode supports in a surrounding mode; the working liquid inlet is communicated with the working liquid flow passage, and the working liquid flow passage is continued to the outside of the two half-type cylindrical electrode;

the two half-type cylindrical electrodes are fixedly installed in a butt joint mode through radial screws on the upper end wall surface;

in the cutting process of the leakage-leading ring, working liquid enters from a working liquid inlet, flows to a discharge gap of the two half-type cylindrical electrodes along a working liquid flow channel, is forced to circulate, is discharged together with an electric corrosion product, is cooled by adopting an upper liquid flushing mode, and is led out to a circulating pump for recycling;

the inner ring taking-out device consists of a first pendulum bob, a clamping outer sleeve and an inner clamping device, wherein the inner clamping device consists of a cylindrical main body A and a clamping jaw;

the cylindrical main body A is assembled by two half-type structures, and is sleeved on a valve rod of the nuclear island electric gate valve when in use, and a clamping jaw is processed at the bottom of the cylindrical main body A;

the number of the clamping jaws is 4-8, the clamping jaws are distributed at equal intervals, and elastic deformation can be performed among the clamping jaws;

a clamping outer sleeve is coaxially sleeved on the outer side of the lower part of the cylindrical main body A, and a first pendulum bob is sleeved on the outer side of the cylindrical main body A above the clamping outer sleeve;

the first pendulum bob and the clamping outer sleeve are respectively assembled by two half-type structures;

the outer ring taking-out device consists of a supporting cylinder, a second pendulum bob and an outer clamping device, wherein the outer clamping device consists of a cylindrical main body B and a supporting claw;

the cylindrical main body B is assembled by two half-type structures, and is sleeved on a valve rod of the electric gate valve of the nuclear island when in use, and a supporting claw is processed at the bottom of the cylindrical main body B;

the supporting claws are claw-shaped with straight outer walls and widened bottom parts of the inner walls;

the number of the supporting claws is 4-8, the supporting claws are distributed at equal intervals, and elastic deformation can be performed between the supporting claws;

a support cylinder is coaxially sleeved on the inner side of the cylindrical main body B, and a second pendulum bob is sleeved at the upper part of the support cylinder extending out of the cylindrical main body B;

the supporting cylinder and the second pendulum bob are respectively assembled by two half-type structures.

The insulating ring frame is of a tile-shaped structure.

The cantilever beam, the connecting frame, the two half-type cylindrical electrode supports and the two half-type cylindrical electrodes are all made of conducting materials, and the insulating ring frame is made of insulating materials, so that direct access of a positive electrode and a negative electrode is avoided.

And a valve rod protective sleeve is coaxially sleeved in the two half-type cylindrical electrode supports.

And a thin-wall sleeve body tightly sleeved on the outer side of the clamping jaw in a pressing manner is processed at the part of the clamping outer sleeve, which is in contact with the clamping jaw.

The bottom of the supporting cylinder is provided with an inclined supporting part which is tightly attached to the inner wall of the supporting claw.

An online replacement method of a nuclear island leakage leading ring by adopting the online replacement device comprises the following steps:

step 1: cutting of the leakage-leading ring

Cutting the middle filler leakage guide ring into an inner ring and an outer ring by adopting a leakage guide ring cutting device;

step 2: inner ring removal

Taking out the inner ring of the leakage guide ring by adopting an inner ring taking-out device;

and step 3: outer ring extraction

Taking out the outer ring of the leakage guide ring by adopting an outer ring taking-out device;

and 4, step 4: replacement of leakage leading ring

Installing a new leakage guide ring on the valve rod, wherein the new leakage guide ring consists of two half rings, two screw holes are respectively processed at two ends of a joint surface, and four inner hexagon screws are used for fastening connection to form a standard complete circular ring.

In the step 1, the upper packing sealing ring is taken down, and then a machine head bracket of the leakage guide ring cutting device is fixedly arranged near one side of the valve rod, which is provided with the packing box;

the two half-cylindrical electrodes are sleeved on the valve rod through the cantilever beam, and are moved to the upper part of the middle filler leakage guiding ring, so that the two half-cylindrical electrodes are positioned at the central position of the upper end surface of the middle filler leakage guiding ring;

at the moment, a discharge surface is formed between the annular bottom surfaces of the two half-type cylindrical electrodes and the intermediate filler leakage guide ring to be cut, pits are formed in the intermediate filler leakage guide ring, the two half-type cylindrical electrodes are controlled to move from top to bottom by using an electric spark control system, the intermediate filler leakage guide ring is subjected to electric striking processing, and the intermediate filler leakage guide ring is gradually cut into an inner ring and an outer ring.

In the step 2, the inner ring taking-out device is used for clamping the inner ring, the inner clamping device firstly extends into the space between the inner ring and the outer ring, the clamping jaws are clamped at the bottom of the inner ring, the clamping outer sleeve is downwards wedged between the outer walls of the clamping jaws and the inner wall of the outer ring through the first pendulum bob, the inner clamping device tightly clamps the inner ring, then the inner ring taking-out device is lifted up in the vertical direction, and finally the inner ring of the leakage-leading ring is taken out.

And 3, clamping the outer ring by using an outer ring taking-out device, inserting a supporting claw of the outer clamping device between the outer ring of the leakage-leading ring and the valve rod, wedging an inclined supporting part at the bottom of the supporting cylinder into the supporting claw to finish the clamping of the outer clamping device and the outer ring, lifting the outer ring taking-out device in the vertical direction, and finally finishing the taking-out of the outer ring of the leakage-leading ring.

The invention has the following remarkable effects:

(1) the replacement method of the nuclear island electric gate valve leakage leading ring can realize the rapid damage of the nuclear island leakage leading ring in a narrow operation space, can ensure that the filler leakage leading ring is taken out and replaced in time as soon as possible in a production field, and has the advantages of simple and convenient operation, rapidness, safety and reliability.

(2) The leakage guide ring cutting device adopts an electric spark (EDM) cutting mode, the leakage guide ring is not easy to loosen and convenient to cut, the condition that electric cutting (hot working) has no cutting force can be avoided, and the leakage guide ring cutting device has better applicability compared with cutting machining and laser machining.

(3) Due to the limitation of the operating environment, the electric spark machine head in the leakage leading ring cutting device adopts a cantilever beam structure form, so that the electrode can extend into the leakage leading ring part of the nuclear island.

(4) According to the leakage guide ring cutting device, the electrode support needs to be separated in actual processing, the valve rod of the nuclear island leakage guide ring mandrel needs to be embraced, and then the electrode support and the electrode are screwed down and connected through the screw, so that the electrode support and the electrode are designed into two half-type cylinders, and the leakage guide ring cutting device has the advantages of being convenient and fast to install.

(5) The inner clamping device, the clamping outer sleeve and the first pendulum bob of the inner ring taking-out device are of a two-half assembly structure, and the outer clamping device, the supporting cylinder and the second pendulum bob of the outer ring taking-out device are convenient to fix after being fast sleeved on the valve rod on line.

(6) The leakage guide ring taking-out device is scientific and reasonable in structural design, is suitable for taking out the leakage guide ring of the nuclear island electric gate valve in a narrow space, and has the advantages of easiness in operation, high taking-out speed and nuclear leakage prevention.

Drawings

FIG. 1 is a schematic view of a leakage ring structure to be processed according to the present invention;

FIG. 2 is a schematic structural view of a cutting device for a leakage-inducing ring according to the present invention;

FIG. 3 is an enlarged view of portion A of FIG. 2;

FIG. 4 is a top view of FIG. 1;

FIG. 5 is a left side view of FIG. 1;

FIG. 6 is a structural diagram of a two-half cylindrical electrode holder;

FIG. 7 is a top view of FIG. 6;

FIG. 7 is a schematic structural view of a two-half cylindrical electrode holder equipped with two-half cylindrical electrodes;

FIG. 8 is a schematic structural view of a two-half cylindrical electrode;

FIG. 9 is a top view of FIG. 8;

FIG. 10 is a schematic view of the inner ring take-out apparatus according to the present invention;

FIG. 11 is an enlarged view of portion B of FIG. 10;

FIG. 12 is a schematic structural view of an outer ring removing device according to the present invention;

FIG. 13 is an enlarged view of section C of FIG. 12;

in the figure: 1-base, 2-stuffing box, 3-holding cylinder, 4-cantilever beam, 5-valve rod, 6-electric spark machine head, 7-machine head support, 8-cylindrical holding seat, 9-connecting frame, 10-screw A, 11-insulating ring support, 12-screw B, 13-cylindrical electrode support, 14-valve rod protective sleeve, 15-screw C, 16-two half cylindrical electrode, 17-middle stuffing leakage-leading ring, 18-lower stuffing sealing ring, 19-fixing ring, 20-screw D, 21-screw hole, 22-mounting table, 23-half cylindrical support body, 24-working liquid inlet, 25-working liquid flow channel, 26-radial screw, 27-upper stuffing sealing ring, 29-first pendulum bob, 30-outer sleeve clamping and clamping, 31-inner clamping device, 33-outer ring, 34-inner ring, 35-cylindrical main body A, 36-thin wall sleeve body, 37-claw, 38-supporting cylinder, 39-second pendulum bob, 40-outer clamping device, 41-supporting claw, 42-inclined supporting part and 43-cylindrical main body B.

Detailed Description

The invention is described in further detail below with reference to the figures and the embodiments.

An on-line replacement device for a nuclear island leakage leading ring comprises a leakage leading ring cutting device, an inner ring taking-out device and an outer ring taking-out device.

As shown in fig. 2 to 5, the leakage-leading ring cutting device includes a base 1, a stuffing box 2, a holding cylinder 3, a cantilever beam 4, an electric discharge machine head 6, a machine head support 7, a cylindrical holding seat 8, a connecting frame 9, an insulating ring frame 11, a cylindrical electrode support 13, a valve rod protective sleeve 14, and two half cylindrical electrodes 16.

The top center position of base 1 is equipped with packing box 2, is equipped with the section of thick bamboo 3 of embracing that is used for holding heavy water in the upper portion outside of base 1.

The bottom end of a valve rod 5 of the nuclear island electric gate valve is inserted into the stuffing box 2, and an upper stuffing sealing ring 27, a middle stuffing leakage-leading ring 17 and a lower stuffing sealing ring 18 which are arranged on the valve rod 5 are all positioned in the stuffing box 2.

The heavy water is used as working water to seal the middle filler leakage guide ring 17 to prevent nuclear leakage. Meanwhile, heavy water is used in the electrical cutting process and can be used as cooling water at the two half-type cylindrical electrodes 16.

The cylindrical embracing seat 8 is of an annular hoop structure and is arranged on the outer side of the upper part of the base 1 and below the embracing barrel 3 in a surrounding manner. The machine head support 7 is fixedly arranged on the cylindrical embracing seat 8, and the electric spark machine head 6 is arranged on the machine head support 7 in an up-and-down moving mode. The electric spark machine head 6 is connected with one end of the cantilever beam 4, an insulating ring frame 11 is vertically connected and installed below the other end of the cantilever beam 4 through a connecting frame 9, and the connecting frame 9 and the insulating ring frame 11 are fixed through a screw A10. A two-half cylindrical electrode holder 13 is coaxially mounted below the insulating ring holder 11 by a screw B12, and a two-half cylindrical electrode 16 is coaxially mounted at the lower part of the two-half cylindrical electrode holder 13 by a screw C15. The insulating ring frame 11 is of a tile-shaped structure. The cantilever beam 4, the connecting frame 9, the two half-type cylindrical electrode supports 13 and the two half-type cylindrical electrodes 16 are all made of conducting materials, and the insulating ring frame 11 is made of insulating materials, so that direct access of a positive electrode and a negative electrode is avoided.

In use, the two half cylindrical electrodes 16 extend into the position of the middle filler leakage-leading ring 17.

The two half-cylindrical electrodes 16 are made of red copper materials and are made into thin-wall cylinders.

As shown in fig. 6, the two-half cylindrical electrode holder 13 is composed of a fixing ring 19 and two semi-cylindrical holder bodies 23, and a mounting table 22 is processed at the outer edge of the upper part of each of the two semi-cylindrical holder bodies 23. As shown in fig. 7, the mounting table 22 is provided with a screw hole 21 fixedly mounted with the insulating ring frame 11, an annular groove is processed on the inner wall of the mounting table 22, a fixing ring 19 is embedded in the annular groove, and the fixing ring 19 is fixedly connected with the semi-cylindrical support body 23 by adopting a spaced screw D20. A valve rod protective sleeve 14 is coaxially sleeved inside the two half-type cylindrical electrode supports 13.

A working liquid inlet 24 is radially processed on the mounting table 22 of one or two of the two semi-cylindrical support bodies 23, a through groove is axially processed on the outer side wall of the valve rod protective sleeve 14, and a working liquid flow passage 25 is defined by the through groove and the inner side wall of the two semi-cylindrical electrode supports 13; the working fluid inlet 24 is communicated with the working fluid channel 25, and the working fluid channel 25 is continued to the outside of the two half-cylindrical electrodes 16, as shown in fig. 8.

As shown in fig. 9, the two half cylindrical electrodes 16 are butt-fixed by radial screws 26 on the upper end wall surface.

In the cutting process of the leakage-leading ring, working liquid enters from a working liquid inlet 24, flows to the discharge gap of the two half-type cylindrical electrodes 16 along the working liquid flow passage 25, is forced to circulate, is discharged together with electric corrosion products, is cooled by adopting an upper liquid flushing mode, and is led out to a circulating pump for recycling.

As shown in fig. 10, the inner ring take-out means is composed of a first bob 29, a gripping outer sleeve 30, and an inner gripping means 31, wherein the inner gripping means 31 is composed of a cylindrical body a35 and jaws 37.

The cylindrical main body A35 is assembled by two half-type structures, and is sleeved on the valve rod 5 of the electric gate valve of the nuclear island when in use, and the bottom of the cylindrical main body A35 is provided with a claw 37. The clamping jaws 37 are 4-8 in number and distributed at equal intervals, and elastic deformation can be carried out among the clamping jaws 37. A gripping outer cover 30 is coaxially fitted on the lower outer side of the cylindrical body a35, and a first pendulum bob 29 is fitted on the upper side of the gripping outer cover 30 and on the outer side of the cylindrical body a 35. As shown in fig. 11, a thin-walled sleeve body 36 tightly pressed and sleeved on the outer side of the claw 37 is formed at the portion of the clamping outer sleeve 30 contacting the claw 37. The first pendulum bob 29 and the clamping outer sleeve 30 are respectively assembled by two half structures.

As shown in fig. 12, the outer ring taking-out device is constituted by a stay 38, a second pendulum 39, and an outer clip device 40, wherein the outer clip device 40 is constituted by a cylindrical main body B43 and a stay 41.

The cylindrical main body B43 is assembled by two half-type structures, and is sleeved on the valve rod 5 of the electric gate valve of the nuclear island when in use, and the bottom of the cylindrical main body B43 is provided with a supporting claw 41. The supporting claws 41 are claw-shaped with straight outer walls and widened bottom parts of the inner walls. The supporting claws 41 are 4-8 in total and distributed at equal intervals, and elastic deformation can be performed between the supporting claws 41. A support cylinder 38 is coaxially fitted inside the cylindrical body B43, and a second pendulum 39 is fitted on an upper portion of the support cylinder 38 extending outside the cylindrical body B43. As shown in fig. 13, a slant supporting portion 42 closely attached to the inner wall of the supporting claw 41 is formed at the bottom of the supporting cylinder 38. The supporting cylinder 38 and the second pendulum bob 39 are assembled by two half-structures respectively.

In the operation of replacing the upper packing seal ring 27 and the lower packing seal ring 18, the upper packing seal ring 27 is removed first, and then the electric discharge machining is performed by using the leak-off ring cutting device. At this time, a discharge surface is formed between the annular bottom surfaces of the two half-type cylindrical electrodes 16 of the leakage guide ring cutting device and the intermediate filler leakage guide ring 17 to be cut, a pit is formed on the intermediate filler leakage guide ring 17, and the intermediate filler leakage guide ring 17 is gradually cut into two parts, namely an inner ring 34 and an outer ring 33 from top to bottom, so that the leakage guide ring is cut.

After the cutting is completed, the inner ring 34 is first gripped by the inner ring-taking out device, and the outer ring 33 is gripped by the outer ring-taking out device. After removal of inner ring 34 is complete, the space of outer ring 33 is increased to provide sufficient space for subsequent removal of outer ring 33.

When the inner ring taking-out device is used for clamping the inner ring 34, the inner clamping device 31 firstly extends into a position between the inner ring 34 and the outer ring 33, so that the clamping jaws 37 are clamped at the bottom of the inner ring 34, the clamping outer sleeve 30 is downwards wedged between the outer walls of the clamping jaws 37 and the inner wall of the outer ring 33 through the first pendulum bob 29, the inner clamping device tightly clamps the inner ring 34, then the inner ring taking-out device is lifted in the vertical direction, and finally the inner ring 34 of the leakage-leading ring is taken out.

When the outer ring taking-out device is used for clamping the outer ring 33, the supporting claw 41 of the outer clamping device 40 is inserted between the outer ring 33 of the leakage guide ring and the valve rod 5, the inclined supporting part 42 at the bottom of the supporting cylinder 38 is wedged into the supporting claw 41 to complete the clamping between the outer clamping device and the outer ring 33, the outer ring taking-out device is lifted up in the vertical direction, and finally the outer ring 33 of the leakage guide ring is taken out.

An online replacement method for a nuclear island leakage leading ring is operated by adopting the replacement device, and comprises the following steps:

step 1: cutting of the leakage-leading ring

Adopting a leakage guide ring cutting device to cut the leakage guide ring;

the upper packing sealing ring 27 is taken down firstly, and then the head support 7 of the leakage-leading ring cutting device is fixedly arranged near one side of the valve rod 5 with the packing box 2; the two half-type cylindrical electrodes 16 are sleeved on the valve rod 5 through the cantilever beam 4, and the two half-type cylindrical electrodes 16 are moved to the upper part of the middle filler leakage leading ring 17, so that the two half-type cylindrical electrodes 16 are positioned at the center of the upper end face of the middle filler leakage leading ring 17; at the moment, a discharge surface is formed between the annular bottom surfaces of the two half-type cylindrical electrodes 16 and the intermediate filler leakage guide ring 17 to be cut, pits are formed on the intermediate filler leakage guide ring 17, the two half-type cylindrical electrodes 16 are controlled to move from top to bottom by using an electric spark control system, the intermediate filler leakage guide ring 17 is subjected to electric striking processing, and the intermediate filler leakage guide ring 17 is gradually cut into an inner ring 34 and an outer ring 33;

step 2: inner ring removal

An inner ring taking-out device is used for clamping an inner ring 34, the inner clamping device 31 firstly extends into a position between the inner ring 34 and an outer ring 33, so that a clamping jaw 37 is clamped at the bottom of the inner ring 34, a clamping outer sleeve 30 is downwards wedged between the outer wall of the clamping jaw 37 and the inner wall of the outer ring 33 through a first pendulum bob 29, the inner clamping device 31 tightly clamps the inner ring 34, then the inner ring taking-out device is lifted up in the vertical direction, and finally the inner ring 34 in the leakage-leading ring is taken out;

and step 3: outer ring extraction

An outer ring taking-out device is used for clamping the outer ring 33, a supporting claw 41 of an outer clamping device 40 is firstly inserted between the outer ring 33 of the leakage guide ring and the valve rod 5, an inclined plane supporting part 42 at the bottom of a supporting cylinder 38 is wedged into the supporting claw 41 to finish the clamping of the outer clamping device 40 and the outer ring 33, then the outer ring taking-out device is lifted up along the vertical direction, and finally the outer ring 33 of the leakage guide ring is taken out;

and 4, step 4: replacement of leakage leading ring

The new leakage guiding ring is arranged on the valve rod 5 and consists of two half rings, two screw holes are respectively processed at two ends of a joint surface, and four inner hexagon screws are used for fastening connection to form a standard complete ring.

The present invention has been described in detail, but the above description is only a preferred embodiment of the present invention, and is not to be construed as limiting the scope of the present invention. All equivalent changes and modifications made within the scope of the present invention shall fall within the scope of the present invention.