JPS5937197B2 - Bolt attachment/detachment transfer device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a device that automatically attaches, detaches, and transfers bolts, and particularly relates to a device suitable for attaching, detaching, and transferring stud bolts attached to a nuclear reactor pressure vessel.

The reactor pressure vessel is configured such that the pressure vessel body and the upper mirror, which is a sealed head placed on the pressure vessel body, are connected by stud bolts, so that the entire pressure vessel is hermetically sealed.

Nuclear reactors undergo periodic (
It is necessary to remove the upper mirror of the pressure vessel (approximately once a year), but in this case, it is necessary to remove all the dozens of bolts attached to the flange of the pressure vessel.

In the past, bolts were removed manually, but
These bolts are large, with a diameter of 1,501 mm, a length of 1,800 kg, and a weight of about 25 kg, so it takes a great deal of effort and time to remove and install them.

Furthermore, there was a risk that workers would be contaminated by radioactivity around the pressure vessel, making it impossible to work for long periods of time, further deteriorating work efficiency.

For this reason, the inventor previously developed a bolt attachment/detachment transfer device shown in FIG. 1, and greatly improved workability.

To explain the outline of this device, a plurality of female threaded portions (not shown) are formed inside the hanging tool main body 7.
After arranging the hanging tool main body T to a plurality of bolts (6 in the figure) 3, insert the hanging tool main body T through the opening 7a and insert the rotation shaft of the bolt rotation device (not shown) into the keyway 3a of the bolt 3.
and rotate the bolt to release the screwed state between the bolt 3 and the pressure vessel 2.

With the release of this screwed state, the bolt 3 is removed from the hanging tool main body T.
The female threaded portion rising to the side and formed inside the main body and the bolt 3
are screwed together.

When the screwing state between the bolt 3 and the pressure vessel 2 is completely released, the hanging tool main body 7 is pulled up together with the bolt via the transfer tool 9 and transferred to a predetermined location by an overhead running lane.

An object of the present invention is to provide an apparatus which is an improvement on the above-mentioned bolt attachment/detachment/transfer apparatus, and which can more reliably screw the hanging tool body into the bolt.

In short, this invention is a device characterized by comprising an upper guide for rotating a bolt, a moving guide that rotates together with the upper guide, and a bolt suspension body that suspends the bolt by screwing into a female thread formed at the top of the bolt. It is.

Embodiments of the present invention will be described below with reference to the drawings.

FIGS. 2A and 2B show cross-sectional views of the suspension device main body 7, FIG. 2A shows a state in which the bolt and pressure vessel are unscrewed, and FIG. 2B shows a state in which the screwed state is released and the bolt is unscrewed. Indicates the state in which the transfer is possible.

First, when removing the bolts, a guide tube 7b formed at the lower part of the hanging tool main body 7 and having a specified height is placed on each bolt 3, and the bolt to be removed and the hanging tool main body 7 are positioned.

13 is an upper guide rotatably supported by a bearing 16, and 19 is a cam follower fixed to the lower end of this upper guide 13.

Reference numeral 14 denotes a movement guide, which is a guide groove 14a formed on the inner wall.
The cam follower 19 is engaged with the cam follower 19.

Reference numeral 15 denotes a female threaded body attached to the suspender main body 7 via a rubber packing 18, and is configured to be screwed into a male threaded portion 14a formed on a part of the outer peripheral surface of the moving guide 14.

Reference numeral 20 denotes a hanging body disposed within the upper guide 13 and the moving guide 14, the lower end of which is a male threaded portion 20a that is screwed into a female threaded portion formed at the top of the bolt 3.

21 is a flange body that prevents the hanging body 20 from falling off.

Next, bolt removal using this device will be explained.

First, when the main body of the apparatus is properly placed on the bolt 3, the upper guide 13 and the moving guide 14 will be in a state as shown in FIG. 2A.

In this state, the rotating tool 31 for rotating the bolt rotation drive device 300 is inserted through the upper hole 13a at the upper end of the upper guide 13 and engaged with the keyway 20b.

As a result, the hanging body 20 is rotated and the male threaded portion 20a is
and the male threaded part of the bolt 3.

In this way, the plurality of bolts 3 that engage with the hanging tool main body and the hanging body 20 can be screwed together in advance.

The rotating tool 31 is then removed.

Next, either temporarily replace the bolt rotation drive device 300 times or use another rotation device to move the rotation shaft 32 to the upper hole 32a.
, and rotate the upper guide 13.

This rotation is transmitted to the moving guide 14 via the cam follower 19, and rotates the bolt 3 in a direction to release the screwed state.

Reference numeral 14c is a portion for transmitting driving force, and is a bolt engaging portion that engages with a retaining portion at the top of the bolt 3 to transmit the rotational force of the guide 14 to the bolt.

In this case, since the hanging body 20 is arranged to rotate freely with respect to the upper guide 13 and the moving guide 14, the threaded state of the hanging body 20 and the bolt will not be equally affected by the rotation of these upper guides, etc. do not have.

As the threaded state is released, the bolt 3 rises toward the suspender main body 7, and the moving guide 14 also moves upward along the guide groove 14a while rotating, and finally the male threaded part 14b of the moving guide 14 and the female threaded body 15 are screwed together (Fig. 2B).

The male threaded portion 14b and the female threaded body 15 are screwed together, and the bolt 3
When the threaded state between the holder and the pressure vessel is released, and all the bolts that engage with the hanging tool main body are in this state, use a crane or the like to pull up the hanging tool main body 7, remove the bolts, and place it in the designated place. Transport.

Note that when the bolt 3 is suspended, the weight of the bolt is supported by the bolt suspension body 20 and the flange body 21 that supports this suspension body 20.

Note that the bolts are attached to the pressure vessel body by performing the above-mentioned procedure in reverse.

By implementing the present invention, large bolts such as stud bolts of a nuclear reactor pressure vessel can be easily and reliably attached and detached.

[Brief explanation of the drawing]

Fig. 1 is a perspective view of the bolt attachment/detachment transfer device, Fig. 2A is a partial cross-sectional view of the suspension main body, showing the state before the bolt is pulled up, and Fig. 2B is a partial cross-sectional view showing the state of the bolt being pulled up. Third
The figure is a sectional view taken along the line AA in FIG. 2. 3... Bolt, 7... Hanging tool body, 13... Upper guide, 14... Movement guide, 14a... Guide groove , 14b...
・Male thread part, 15...Female thread body, 19...
...Cam follower, 20... Hanging body.

Claims (1)

[Scope of Claims] 1. An apparatus for attaching and detaching bolts using a hanging tool body, which includes: an upper guide that engages with a bolt rotation drive device to rotate; and an upper guide that engages with the upper guide and supports raising and lowering of the bolt. a moving guide that moves up and down, a hanging body disposed within the upper guide and the moving guide and having a male threaded part that screws into the female threaded part of the bolt, and a male threaded part formed on a part or all of the outer peripheral wall of the moving guide. A bolt attachment/detachment/transfer device characterized by having a female threaded body screwed together with a hanging tool main body. 2. Claim 1, characterized in that the upper guide is provided with a cam follower, and the cam follower is disposed in a guide groove formed in the axial direction of the inner wall of the moving guide to engage the upper guide and the moving guide. Bolt attachment/detachment transfer device.