JPH0820540B2 - Device for attaching and detaching stud bolts - Google Patents

Description

TECHNICAL FIELD The present invention relates to a stud bolt attachment / detachment device, and in particular,
The present invention relates to a technique for attaching and detaching a stud bolt for fixing an upper lid of a reactor pressure vessel to a vessel body.

"Prior Art" Generally, the upper lid of a reactor pressure vessel in a boiling water reactor is fastened by a stud bolt and a nut erected on the body of the vessel. Also, at the time of fuel rod replacement and periodic inspections after the start of reactor operation, various work will be performed with the upper lid removed, but the stud bolts used for fastening are the fuel rods. It is necessary to remove from the body of the container for convenience of transportation and confirmation of quality maintenance. Since this attachment / detachment work is performed within the radioactive management area, it is necessary to efficiently perform it with a small amount of labor.

The applicant has proposed JP-B-58-17737 [stud bolt attachment / detachment device] and JP-B-59-11433 [nut attachment / detachment work equipment], and with these technologies, labor saving during attachment / detachment of stud bolts and nuts , Shortening the construction period,
We have achieved a reduction in worker exposure.

[Problems to be Solved by the Invention] However, in the above-mentioned conventional [stud bolt attaching / detaching device], the bolt loosening portion and the bolt suspending portion are separately suspended by suspending means such as a hoist. Since the structure is located above the stud bolt,
If the stud bolts used to fasten the upper lid of the reactor pressure vessel are simultaneously attached and detached at multiple locations,
There were problems such as having to solve the problem by arranging multiple hoists and arranging them, or by making special arrangements.

The present invention is intended to solve the problems of the prior art as described above. When the stud bolt is attached / detached, transported, etc. rationally, and when applied to a reactor pressure vessel, the upper lid is The purpose is to improve workability and automation by improving the relative relationship with.

"Means for Solving Problems" The stud bolt attaching / detaching device according to the present invention is supported by a turning table which is attached to the upper lid of the reactor pressure vessel so as to be able to turn, and attaches / detaches a stud bolt for fastening the upper lid. A unit base that can be moved up and down with respect to the swivel table, a bolt suspension unit that is integrally supported by the unit base, and a unit base that is movable in the axial direction of the stud bolt. And a casing attached to the unit stand in an upright state. The bolt suspension is moved up and down in the casing by the elevating means arranged in the casing. An elevating rod, a rotating rod rotatably attached to the elevating rod, and a pair of vertically movable and rotating pairs with respect to the rotating rod. And a suspension rod integrally attached to the suspension rod, and a male screw portion formed at a lower end of the suspension rod and screwed into a screw hole of a head portion of a stud bolt. The bolt loosening portion is a suspension bolt. It employs a technology that includes a wrench portion that rotates around and engages detachably with the head of the stud bolt and that rotates the stud bolt in synchronization with the movement amount of the suspension rod.

[Operation] When removing the stud bolt, release the fastening state of the upper lid with the nut and the stud bolt in advance,
By lowering the unit base, the lower end of the suspension rod in the bolt suspension portion and the wrench portion in the bolt loosening portion are aligned with the upper position of the stud bolt.

By the operation of the bolt suspension portion, the tip of the suspension rod is screwed into the internal thread portion of the head of the stud bolt.

Next, the suspension rod is lifted, the stud bolt is biased upward to support the load of the stud bolt, and the bolt loosening portion is activated, and the stud bolt is rotated by the wrench portion to loosen it. Lift the suspension rod in synchronization with the rising speed when the stud bolt is relaxed.

When the gradually loosened stud bolt comes off the threaded part of the flange, stop the operation of the bolt loosened part, lower the stud bolt suspended by the bolt suspension part, and transfer it to the required place. To do.

On the other hand, the mounting work for screwing the stud bolt into the threaded portion of the flange is performed in almost the reverse order of the work for removing the stud bolt, and even in this case, the stud bolt load is supported by the bolt suspension portion. ,
Operate the bolt loosening part and rotate the stud bolt with no load and screw it together.

After that, the nut is screwed onto the stud bolt to fasten the upper lid and the container body, and the like.

"Example" Hereinafter, a device for attaching and detaching a stud bolt according to the present invention will be described.
An embodiment in the case of being applied to a stud bolt and a nut fastening an upper lid of a reactor pressure vessel will be described with reference to the drawings.

In the figure, symbol A is a reactor pressure vessel, symbol B is a vessel body,
Reference numeral C is a top lid, reference numerals D and E are flanges, reference numeral F is a stud bolt, reference numeral G is a nut, reference numeral H is a washer, reference numeral I is a reactor containment vessel, reference numeral 1 is a top lid opening / closing device, reference numeral 2 Is a fixed sling, reference numeral 3 is a leg, reference numeral 4 is a turning table, reference numeral 5 is a centering device, reference numeral 6 is a unit lifting device, reference numeral 7 is a unit stand, reference numeral 8 is a stud tensioner, reference numeral 9 is a stud bolt attaching / detaching device, Reference numeral 10 is a nut transfer device.

First, the outline of the upper lid opening / closing device 1 attached to the upper lid C of the reactor pressure vessel A will be described.

As shown in FIGS. 5 to 7, the attachment pieces Ca provided at a plurality of positions on the outer surface of the upper lid C for hanging are provided with the fixed sling 2 in the upper lid opening / closing device 1.
Each leg 3 of is attached. On the fixed sling 2, a turning table 4 horizontally turning along the pitch circle of the stud bolt F is mounted while being supported by the rollers 11.

The centering device 5 is disposed between the fixed sling 2 and the turning table 4, and moves the turning table 4 back and forth and left and right (horizontal directions) to make the turning table 4 concentric with the pitch circle. It is to be placed.

Below the periphery of the turntable 4, working units for performing various works, for example, 90 ° apart in the circumferential direction of the pitch circle, that is, the stud tensioner 8, A plurality of stud bolt attachment / detachment devices 9, a nut transfer device 10, a positioning device (not shown), and the like are arranged on the unit base 7 (for example, four units each), and a chain block and the like. A ring-shaped work scaffold 13 in a suspended state is provided on the suspension device 12 of FIG. When the work scaffold 13 is hung by the suspension device 12, the work scaffold 13 is supported by a projecting step (bulkhead or the like) on the inner wall of the reactor containment vessel I with its peripheral portion placed. When performing various subsequent work,
It is used in a state where it is disconnected from the turning table 4 by disconnecting the connection (for example, a chain) by the suspension device 12.

The unit lifting device 6 is an electric servomotor provided on the revolving table 4 for each one.
14 and a speed reducing mechanism 15 of the electric servomotor 14, and three ball screw jacks 16 connected to the speed reducing mechanism 15 and operated synchronously, and the unit base 7 is moved up and down with respect to the turning table 4. It has a function of moving parallel to the direction.

The stud tensioner 8 is configured by combining a tensioning function of applying tension to the stud bolt F and a nut rotating function of rotating the nut G in a state where the stud bolt F is extended. 17 is provided with a function of moving the tensioner 8 supported by the operation of the lifting mechanism 17 in a state of vertically penetrating the unit base 7 in synchronization with the moving speed of the rotating nut G. There is.

The stud bolt attaching / detaching device 9 is a portion related to the present invention, and in one embodiment, a bolt suspending portion 18 integrally supported by the unit base 7 supported by the turning table 4, The basic structure is provided with a bolt loosening portion 19 that is supported so as to be movable in the axial direction of the stud bolt F with respect to the unit base 7, and a casing 20 is provided on the unit base 7 as shown in FIG. It is attached in an upright state by fasteners such as bolts and nuts, and as shown in FIG. 2, the respective parts constituting the bolt suspending portion 18 are accommodated in the upper part and inside of the casing 20, and
A bolt loosening portion 19 is supported in the casing 20 so as to be movable in the axial direction.

That is, the details of the stud bolt attaching / detaching device 9 will be described below mainly with reference to FIGS. 1 to 4, and the bolt suspending portion 18 of the stud bolt attaching / detaching device 9 will be described below.
Is an ascending / descending motor 21 mounted outside the upper part of the casing 20, an ascending / descending means 22 such as a screw jack driven by the ascending / descending motor 21 to convert a rotational movement into an ascending / descending movement, and the ascending / descending means 22. An elevating rod 23 that can be moved up and down in the casing 20 (movement in the axial direction of the stud bolt F), and freely rotatable (rotatable with respect to the axis of the stud bolt F) via the coupling 24 to the elevating rod 23. The attached rotating rod 25, the suspension rod 26 that is vertically movable relative to the rotatable rod 25, and is integrally attached in the rotation direction, and the suspension rod.
An elastic member 27 interposed between the rotating rod 25 and the rotating rod 25 to exert an urging force to move the suspending rod 26 upward with respect to the rotating rod 25, and is formed at the lower end of the suspending rod 26. And a male screw portion 28 screwed into a screw hole Fc at the center of the head of the stud bolt F.

Around the rotary rod 25, a plurality of vertical position sensors 25 for detecting the vertical position of the rotary rod 25.
A suspension rod rotation mechanism 29 and a, 25b, 25c are provided. The lifting rod rotation mechanism 29 includes a guide rail 30 that is integral with the inner surface of the casing 20, and an elevating frame 31 is movably supported on the elevating frame 31, and a screw rotating motor 32 is attached to the elevating frame 31. The rotation driving force of the rotation motor 32 is transferred to the rotation rod via the gear 33 and the gear 34.
The structure is such that the suspension rod 26 fixed to the intermediate sleeve 35 is rotated by being transmitted to the intermediate sleeve 35 surrounding the 25 and the suspension rod.

The bolt loosening portion 19 includes a wrench rotating motor 37 mounted on the elevating frame 31 and the wrench rotating motor 37.
The rotary driving force of 37 is transmitted to the outer sleeve 40 surrounding the intermediate sleeve 35 with a gap via the gear 38 and the gear 39, and is suspended by the outer sleeve 40 via the spline 41. The wrench part is for rotating the part 42.
42 and the lower inside of the outer sleeve 40 between the wrench 42
The elastic member 43 for projecting downward is installed inside, and the lower part of the outer sleeve 40 has an alignment sleeve 44
Is externally fitted, and the taper portion of the inner surface is covered on the head of the stud bolt F to perform centering. In the vicinity of the elevating frame 31, a support sleeve 45 for rotatably supporting the outer sleeve 40,
A plurality of vertical position sensors 45a, 45b for detecting the relative relationship with the stud bolt F are provided around the support sleeve 45 while being integrally provided with the elevating frame 31.

Then, the bolt suspension portion 18 and the bolt loosening portion 19 are
A means for synchronously operating the stud bolt F rotated by the wrench portion 42 so that the amount of movement of the stud bolt F in the axial direction matches the amount of movement of the suspension rod 26 (for example, the amount of movement of the stud bolt F due to the rotation means 22). A synchronizing means for adjusting the rotation of the lifting motor 21 is provided so as to match the movement amount of the lifting rod 23 due to.

Further, as shown in FIGS. 5 and 6, the nut transfer device 10 removes the nut G loosened by the stud tensioner 8 and the washer H below the nut G from the stud bolt F, if necessary, and The scaffolding 13 is transported to a desired position and is supported by a pin-shaped nut support mechanism 46 arranged at the same pitch angle so as to correspond to each stud bolt F.

In addition, a suspension piece 47 that is formed so as to project upward, a sensor platform 48 that surrounds the suspension piece 47, and the sensor platform 48 are provided above the center of the fixed sling 2.
A turning motor 49 such as an electric servomotor, which is a drive source for turning the turning table 4 and is mounted on the vehicle, and a rack and pinion mechanism for turning the turning table 4 when the turning motor 49 is operated are provided. Further, a swing platform 50 formed on the upper surface of the swing table 4 is disposed around the sensor platform 48, and the swing platform 50 is used to give commands based on the execution of various operations. The operation panel 51 etc. are installed.

In FIG. 1, reference numeral 52 is a spacer for supporting the stud bolt F, and a spacer having a split sleeve shape is externally fitted to the stud bolt F.
It is used to support the stud bolt F by interposing it between the flange D and the stepped portion Fd of the stud bolt F.

Hereinafter, an opening / closing process of the upper lid C of the reactor pressure vessel A and a stud bolt attaching / detaching process which is generated based on the opening / closing process will be described.

[Setting process of upper lid opening / closing device] The upper lid opening / closing device 1 stored on the operating floor or the like is hung by a crane or the like and lowered onto the reactor pressure vessel A, and the legs 3 of the fixed sling 2 are placed on the upper lid. The upper lid opening / closing device 1 is attached to the attachment piece Ca of C, and the center of the turning table 4 is aligned with the center of the pitch circle of the stud bolt F by the operation of the centering device 5 to move the upper lid opening / closing device 1 to the reactor pressure. Place on top of Container A.

[Work Scaffold Setting Process] The suspension device 12 is operated to lower the work scaffold 13 to the projecting step portion on the inner wall of the reactor containment vessel I, and the stud bolt F and the nut support mechanism 46 of the nut transfer device 10 are installed. , Align in the radial direction of the pitch circle.

[Step of Setting Turning Position] The turning table 4 is turned by the operation of the turning motor 49, and the horizontal position of the stud bolt F to be loosened is aligned with the horizontal position of the stud tensioner 8.

[Setting of unit base] The unit lifting device 6 is operated to lower the unit base 7 and each working unit from the turning table 4, and
The positioning device provided on the unit base 7 detects the position of the stud bolt F, for example, which is separated by several pitches from the position below the stud tensioner 8 to perform accurate positioning in the circumferential direction of the pitch circle by fine adjustment. . By this positioning, the tip of the stud tensioner 8 mounted on the unit base 7 can be positioned with respect to the stud bolt F to be loosened.

In this alignment state, the stud bolt attaching / detaching device 9 is at a position spaced apart by three times the pitch of the stud bolts F in the circumferential direction as shown in FIG. The stud bolt F at the same position as the tensioner 8 is set as a work target and is in a standby state in the vicinity thereof.

[Tensioning Step] By operating the stud tensioner 8, the grip portion Fb of the stud bolt F is grasped and pulled up,
While the stud bolt F is extended, the nut G is rotated to gradually release the screwed state, and the lifting mechanism 17
The stud tensioner 8 is moved upward while being synchronized with the moving speed of the nut G by. Stud bolt F
Remove the nut G from the thread Fa of the
The stud tensioner 8 is further raised and retracted to a position above the stud bolt F. Further, the loosened nut G is placed on the thread portion Fa of the stud bolt F.

[Operation of Nut Conveying Device] The nut conveying device 10 is activated and the stud tensioner 8 is activated.
The nut G placed on the thread portion Fa of the stud bolt F is pulled out from the stud bolt F by moving it upward, and the washer H located below the nut G is sucked. In the same manner, the nut G and the washer H are externally fitted and supported on the nut support mechanism 44 installed on the work scaffold 13 by taking them out from the stud bolts F, and carrying them in a required place.
During these carrying operations, the combination of the stud bolt F, the nut G, and the washer H is not changed by separating the stud bolt F from the stud bolt F radially outward of the pitch circle. By repeating the same operation, the nut G and the washer H are successively
Will be removed from the stud bolt F.

[Stud Bolt Extraction Step] When removing the stud bolt F from the container body B of the reactor pressure vessel A, at least the target stud bolt F can be extracted by the operation of the stud tensioner 8.

<Positioning of Wrench> The unit elevating device 6 is operated to gradually lower the unit table 7 and lower it to the lower position of the guide rail 30 from the elevating frame 31 and the outer sleeve 40 which are supported in a suspended state. The positioned alignment sleeve 44 is lowered. This lowering degree is detected by the vertical position sensors 31a and 31b provided around the support sleeve 45, and the positioning sleeve 44 is moved to the stud bolt F as shown in FIG.
The wrench portion 42 and the stud bolt F are centered by externally fitting over the head portion of the wrench. At this time, the centering also aligns the male screw portion 28 at the lower end of the suspension rod 26 of the bolt suspension portion 18 with the screw hole Fc of the stud bolt F.

<Screw engagement of bolt suspending portion> The bolt suspending portion 18 is operated, the elevating rod 23 is lowered by the driving force converting means 22, and the male screw portion 28 at the lower end of the suspending rod 26 is screwed into the screw hole Fc of the stud bolt F. To match. The relative height between the male screw portion 28 and the stud bolt F is detected by the position sensor 25b. In addition, the wrench rotation motor 37 is operated by the signal of the detection sensor 25b, the suspension rod 26 is rotated through the intermediate sleeve 35, and the male screw portion is rotated.
Screw 28 into screw hole Fc. In this case, the lifting motor 21 is operated to lower the suspension rod 26 in accordance with the screwing amount. The amount of descent is detected by the vertical position sensor 25c.

<Support of stud bolt load> After screwing the male screw part 28 and the screw hole Fc, the bolt holding part 18
And urge the stud bolt F upward. That is, by elevating the elevating rod 23 and the rotating rod 25, elastic deformation is generated against the elastic force of the elastic member 27, and the movement amount of the rotating rod 25 is detected by the vertical position sensor 25.
b, 25a. At this time, the vertical position sensor 25
b indicates that the pulling force of the stud bolt F by the rotating rod 25 is almost 0, and the vertical position sensor
In 25a, the pulling force is a set load (for example, a load in which the weight of the stud bolt F is added to the weight of the bolt loosening portion 19).
Detect that it has reached.

<Loosening of Stud Bolt> The bolt loosening portion 19 is operated, and the wrench rotating motor 37 drives the wrench portion through the outer sleeve 40 and the spline 41.
42 is rotated to loosen the stud bolt F. In this case, the stud bolt F is in a so-called no-load state in which the weight of the stud bolt F is supported by the bolt suspension portion 18, and therefore, the rotational torque at the time of loosening can be suppressed to be small. Further, the stud bolt F is loosened and lifted, so that the bolt loosened portion 19 is lifted and its relative position with the stud bolt F does not change.

On the other hand, the bolt suspension 18 is activated to move the stud bolt F.
When the elevating rod 23 and the rotating rod 25 are moved up at a speed synchronized with the rising speed at the time of relaxation, the relative relationship between the rotating rod 25 and the hanging rod 26 is maintained, and the load is supported by elastic force. It is possible to raise the stud bolt F while giving it a smooth rotation as it is.

<Treatment of Stud Bolt> In this way, the stud bolt F is extracted from the screw hole of the flange E in the container body B and conveyed to a required location. If necessary, as shown in FIG. 1, the small-diameter portion Fd formed between the thread portion Fa and the grip portion Fb of the stud bolt F may be attached to the small-diameter portion Fd, for example, the above-mentioned split sleeve spacer 52. Is externally fitted, placed on the flange D, and the stud bolt F is suspended.

[Opening and Transporting the Top Lid] After removing all the nuts G and washers H and supporting them with the stud bolts F and the spacers 51 as shown in FIG. 1, the hanging position 12 and the work scaffold 13 are connected, By elevating the work scaffold 13, the work scaffold 13 is lifted from the projecting step portion on the inner wall of the reactor containment vessel I and is suspended from the fixed sling 2, and a crane or the like is connected to the suspending piece 46 of the fixed sling 2. , The swivel table 4, the upper cover C, the work scaffold 13 and the like are hung together with the fixed sling 2 and transported and stored on the operating floor.

[Stud Bolt Attaching Process] On the other hand, the attaching work of screwing the stud bolt into the bolt hole is performed in a state of being attached to the closing process of the upper lid C, and is almost the reverse process of the removing work of the stud bolt described so far. Detailed description will be omitted.

Explaining the outline, the upper lid C stored on the operating floor, the stud bolts F, etc. suspended from the upper lid C are hung together with the fixed sling 2 and the turning table 4 by a crane or the like, and the reactor pressure is Lower it onto the container A and make settings such as alignment. As for the stud bolts F not hung on the upper lid C, all the stud bolts F are screwed by conveying them to the vicinity of the upper lid C and the flange D of the container body B and inserting them into the screw holes Fc. Attaching / detaching device for stud bolts 9 while standing in the hole Fc 9
Operate.

That is, after these settings, the stud bolt F is supported by the bolt suspension 18 in the stud bolt attaching / detaching device 9, and the frictional force due to the load of the stud bolt F is generated between the screw hole Fc and the screw portion Fa. While keeping the state where it does not directly act, the bolt loosening portion 19 is actuated, the stud bolt F is rotated by the wrench portion 42, the screwing of the stud bolt F is deepened, and the stud bolt F is erected on the container body portion B sequentially. The installed state.

Then, the nut G is rotated by the operation of the stud tensioner 8 to be screwed into the stud bolt F, and
By the operation of the stud tensioner 8, a work for fastening the upper lid C and the container body B is performed.

In one embodiment, the stud bolts are attached / detached by each of these steps, but since the stud bolt attaching / detaching device is mounted on the unit base and attached to the turning table, the upper lid opening / closing is performed. The device, the upper lid, the stud bolt, the nut, the washer, etc. can be collectively transported to the operating floor and stored together, and the workability when opening and closing the upper lid is significantly improved.

Also, when the stud bolt is loosened or attached, the load of the stud bolt is supported by the bolt suspension, and the stud bolt is rotated so that it is not affected by the frictional resistance force due to the load. Thus, the screwing can be made smooth and the workability can be improved.

Further, the movement amount of the stud bolt in the axial direction along with the rotation and the movement amount of the bolt loosening portion are absorbed by the relative movement with respect to the unit base, and the stud bolt supporting portion supports the load of the stud bolt. By moving the suspension rod in synchronism with the amount of movement of the bolt, it is possible to reduce the load applied to the screwing portion, and to suppress the occurrence of scratches during the screwing and the scattering of radioactive substances.

[Other Embodiments] Instead of the above-described embodiments, the following can be performed.

(B) Remove only the required number of stud bolts from the container body.

(B) Install two or more stud bolt attaching / detaching devices on the unit base.

(C) In addition, the number of unit units shall be any number other than four.

(D) To obtain the driving force of each part by electric pressure, hydraulic pressure, pneumatic pressure, or the like.

(E) Rotate the stud bolt in the bolt loosening part,
Follow the conventional example and use intermittent impact force.

(F) In the reactor pressure vessel, the stud bolt extraction process should be performed in connection with the stud bolt cleaning process.

(G) In the above case, a stud bolt cleaning device should be installed near the stud bolt attaching / detaching device.

[Advantages of the Invention] As described above, according to the attachment / detachment device of the stud bolt according to the present invention, the suspension rod that is screwed to the head of the stud bolt is attached to the stud suspension portion integrated with the unit base. The stud bolt head is provided so as to be movable along the axial direction of the bolt, and is provided with a bolt loosening portion that is movable in the axial direction with respect to the unit base, and the bolt loosening portion rotates around the hanging bolt. Is provided with a wrench portion that is detachably engaged with the bolt suspension portion, and the bolt suspension portion moves the suspension rod in synchronization with the amount of axial movement of the stud bolt rotated by the wrench portion. Since the structure is provided with the elevating means, the following excellent effects are obtained.

Since the bolt suspending portion and the bolt loosening portion are supported by one unit base, there is no need to separately suspend the suspension as in the conventional example, and there are few restrictions on the installation location.

By mounting the bolt suspending portion and the bolt loosening portion on the unit base, it is possible to downsize the device and improve the accuracy.

When rotating the stud bolt in a screwed state, it is supported by the load bolt suspension part of the stud bolt,
It is possible to improve the workability of a heavy stud bolt or the like by screwing and rotating the stud bolt with the contact pressure of the screw portion being substantially unloaded.

The support state by the bolt suspension is changed in synchronism with the axial movement of the stud bolt that accompanies the screw rotation, so that there is no change in the contact part due to screw rotation during attachment / detachment work. , Can improve stability.

By applying it to the stud bolts that fasten the reactor pressure vessel, the load applied to the screwing part is reduced, the occurrence of scratches during screwing and the scattering of radioactive materials are suppressed, and the exposure of workers is reduced. Can be achieved.

When applied to a reactor pressure vessel, it can be mounted on a unit base and improved in accuracy, so that removal of stud bolts during a periodic inspection and automation of a transfer work process can be achieved.

[Brief description of drawings]

The drawings show an embodiment in which the nut conveying device according to the present invention is applied to a stud bolt and a nut for fastening an upper lid of a reactor pressure vessel. FIG. 1 is a perspective view of a main part, and FIG. The figure is a front view of the main part with a part cut away,
The drawing is a view taken along the line III-III in FIG. 2, and FIG. 4 is the IV- in FIG.
A view taken along the line IV, FIG. 5 is a perspective view of an upper lid opening / closing device equipped with a nut carrying device, and FIGS. 6 and 7 are a front view and a plan view in which a part of the upper lid opening / closing device is omitted. A ... Reactor pressure vessel, B ... Vessel body, C ... Upper lid, Ca ... Mounting piece, D ... Flange, E ... Flange, F ... Stud bolt, Fa ... Threaded portion, Fb ... … Gripping part, Fc… Screw hole, Fd… Stepped part, G… Nut, H… Washer, I… Reactor containment vessel, 1… Top lid opening / closing device, 2… Fixed sling, 3… … Legs, 4 …… Turning table, 5 …… Centering device, 6 …… Unit lifting device, 7 …… Unit stand, 8 …… Stud tensioner, 9 …… Stud bolt attaching / detaching device, 10 …… Nut transfer device , 11 …… roller, 12 …… suspension device, 13 …… work scaffolding, 14 …… hydraulic motor, 15 …… deceleration mechanism, 16 …… ball screw jack, 17 …… elevation mechanism, 18 …… bolt suspension part , 19 ...... Bolt loosening part, 20 ...... Casing, 21 ...... Lifting motor, 22 ...... Lifting means 23 ... Lifting rod, 24 ... Coupling, 25 ... Rotating rod, 25a ... Vertical position sensor, 25b ... Vertical position sensor, 25c ... Vertical position sensor, 26 ... Lifting rod, 27 ... Bullet Generating member, 28 …… Male screw part, 29 …… Hanging rod rotating mechanism, 30 …… Guide rail, 31 …… Lift frame, 32 …… Screw rotating motor, 33 …… Gear, 34 …… Gear, 35… … Intermediate sleeve, 37 …… Wrench rotation motor, 38 …… Gear, 39 …… Gear, 40 …… Outer sleeve, 41 …… Spline, 42 …… Wrench part, 43 …… Elastic member, 44 …… Position Aligning sleeve, 45 ... Support sleeve, 45a ... Vertical position sensor, 45b ... Vertical position sensor, 46 ... Nut support mechanism, 47 ... Suspension piece, 48 ... Center platform, 49 ... Rotating motor, 50 …… Swivel platform, 51 …… Operation panel, 52 …… Spacer

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁶ Identification number Reference number within the agency FI Technical indication location G21F 9/28 ZAB 541 B (72) Inventor Yutaka Omura 1 Shinshinarahara-cho, Isogo-ku, Yokohama-shi, Kanagawa Ishikawajima Harima Heavy Industries Co., Ltd. Yokohama No. 1 Factory (72) Inventor Toshio Kojima 3-15-15 Toyosu, Koto-ku, Tokyo Ishikawajima Harima Heavy Industries Co., Ltd. Technical Research Institute (56) Reference JP 59-142074 (JP) , A) JP 60-141478 (JP, A) JP 57-121479 (JP, A) JP 58-17737 (JP, Y2)

Claims (1)

[Claims] 1. A device for attaching and detaching a stud bolt (F) for fastening an upper lid, which is supported by a swivel table (4) which is swingably mounted on an upper lid (C) of a reactor pressure vessel (A). And a unit base (7) that can be moved up and down with respect to the swivel table, a bolt suspension portion (18) integrally supported with respect to the unit base, and an axial direction of the stud bolt with respect to the unit base. Bolt loosening part (19) movably supported on
And a casing (20) attached to the unit stand in an upright state, wherein the bolt suspending unit is provided with an elevating means (22) arranged in the casing, and the elevating means vertically moves in the casing. Lifting rod (23), a rotating rod (25) rotatably attached to the lifting rod, and a lifting rod (26) integrally attached to the rotating rod in a vertically movable manner and in a rotating direction. And a male screw portion (28) formed at the lower end of the suspension rod and screwed into the screw hole (Fc) of the head of the stud bolt, wherein the bolt loosening portion surrounds the suspension bolt. A stud bolt attaching / detaching device comprising a wrench portion (42) that rotates and detachably engages with the head of the stud bolt and that rotates the stud bolt in synchronization with the movement amount of the suspension rod. .