JPH0812268B2 - Stud bolt elongation measuring device - Google Patents

Description

TECHNICAL FIELD The present invention relates to a stud bolt elongation measuring device for automatically measuring the elongation amount of a large number of stud bolts arranged on the peripheral portion of an upper lid, and more particularly to a stud bolt elongation measuring device. The present invention relates to a measuring device suitable for measuring the amount of extension of a stud bolt attached for tightening the upper lid of a reactor pressure vessel.

[Prior Art] In a reactor pressure vessel, as shown in FIGS. 7 and 8, stud bolts 4 are erected and screwed on a body flange 3 at a predetermined pitch in a circumferential direction in order to attach an upper lid 2 to a body 1. And these stud bolts 4 are attached to the corresponding shaft holes 6 of the upper lid flange 5.
A nut 7 for tightening the upper end portion of the upper lid flange 5 is screwed to the starter bolt 4 so as to penetrate therethrough.

By the way, the upper lid 2 is opened and closed at the time of regular inspection,
At this time, when the nut 7 removed from the stud bolt 4 is screwed to the stud bolt 4 again to tighten the upper lid 2,
The nut 7 is tightened while pulling up the upper lid portion of the stud bolt 4 with a stud tensioner so that a predetermined tension remains on the stud bolt 4. Then, in order to confirm whether or not a predetermined tension remains on the stud bolt 4, the amount of extension of the stud bolt 4 before and after tightening the nut is measured.

[Problems to be Solved by the Invention] However, in the related art, since the worker manually measures the extension amount of the stud bolt by using a dial gauge or the like, it takes a lot of labor and time. Since there is a large amount of radiation dose, especially around the upper lid flange, it was difficult to prevent radiation exposure for workers.

Therefore, the object of the present invention is to solve the above-mentioned problems of the prior art, and to automatically measure the extension amounts of all the stud bolts on the peripheral portion of the upper lid, reducing the labor required for measurement and improving safety. Another object of the present invention is to provide a stud bolt elongation measuring device capable of shortening the time.

[Means for Solving the Problems] In order to achieve the above object, the present invention relates to an elongation measuring rod inserted into the axial center hole of a stud bolt arranged upright along the peripheral portion of the upper lid. A moving frame provided movably along the pitch circle of the stud bolt, and a measuring element supported by the moving frame and in contact with the upper end of the extension measuring rod, and seated on the upper end of the stud bolt. And an elongation measuring device that is used as a stud bolt elongation measuring device.

[Operation] The elongation measuring device is supported by the moving frame, moves along the pitch circle of the stud bolt, and is seated on the upper end of the stud bolt to be measured. At this time, the contact of the elongation measuring device contacts the upper end of the elongation measuring rod inserted into the shaft core hole of the stud bolt. The stud bolt expands in the axial direction due to the applied tension, but the elongation measuring rod remains at its original length.Therefore, the elongation measuring device measures the relative displacement between these stud bolts and the measuring rod. Measure through.

In this way, the amount of elongation of all stud bolts is automatically and sequentially measured. The movement of the moving frame and the sitting / floating operation of the elongation measuring device will be remotely controlled by the operation panel installed at a place apart from the top cover, and the measured values will be displayed and recorded on the operation panel. .

[Embodiment] A preferred embodiment of the present invention will be described in detail below with reference to the accompanying drawings.

As shown in FIGS. 1 and 2, above the upper lid 2 that covers the upper part of the trunk body (not shown) of the reactor pressure vessel, it functions as a hanging structure when the upper lid 2 is removed and moved. A fixed mount 10 having a circular frame structure is arranged. The pedestal 10 is provided with a hanging hardware 12 to be hung on the crane hook 11 on the central upper surface thereof.
It is suspended and supported by a crane or the like. In addition, a turnbuckle-like joint that is connected to a joint end 13 provided on the upper lid 2 for suspending and supporting the upper lid 2 under the pedestal 10 when the upper lid 2 is moved on the lower surface of the peripheral portion of the pedestal 10. A member 14 is provided. Further, a radial roller 15 for centering that is expandable and contractible is radially provided in the central cylindrical portion of the gantry 10, and these rollers 15 are expanded and contracted from the central cylindrical portion by a turnbuckle 16 to form a rolling surface of the rotary table 17. The core of the gantry 10 and the rotary table are pushed by being pressed against 18.
By correcting the deviation from the 17 core and adjusting it to the pitch circle of the stud bolt 4, the entire device is positioned. Further, a roller support frame 19 that supports the roller 15 is provided with a pinion 21 that meshes with an annular internal gear 20 provided on the inner peripheral portion of the rotary table 17, and this pinion 21 is provided on the roller support frame 19. A motor 22 with a reducer mounted on the vehicle is connected, and the motor 22 drives the pinion 21 to rotate the rotary table 17 around the gantry 10.

On the outside of the peripheral side portion of the fixed mount 10 thus configured,
An annular rotary table 17 is provided above the upper lid 2 and is rotationally driven along the circumferential direction of the upper lid flange 5. Thrust rollers 24 are arranged on the rotary table 17 along the circumferential direction of the gantry 10 so as to engage with rails 23 formed on the horizontal portion of the rim of the gantry 10. And turntable 17
Are rotatably supported with respect to the gantry 10 by rollers 24 that engage with rails 23. Further, the rotary table 17 is provided for each pitch of the stud bolts 4 which are planted on the upper lid flange 5.
It is controlled to be driven in the range of 90 °.

The rotary table 17 thus configured is provided with four lifting frames 25 at 90 ° intervals along the circumferential direction. The elevating frame 25 is connected to a pair of screw jacks extending vertically from the rotary table 17 and expanding / contracting means 26 such as a hydraulic cylinder at both ends of the upper lid flange 5 along the circumferential direction. It is hung and supported from 17 to the upper lid flange 5 side so as to be able to move up and down. In particular, the expanding and contracting means 26 are rotatably attached to the rotary table 17 and the elevating frame 25, and support the elevating frame 25 under the rotary table 17 so as to be swingable. This is a configuration for allowing the copying operation of the elevating frame 25 by the copying apparatus 27 described later.

Each of the lifting frames 25 configured in this way,
A copying device 27 that follows the stud bolts 4 erected on the upper lid 2 to guide the lifting and lowering movements thereof, a bolt cleaning device 28 for performing work on the stud bolts 4 and nuts 7 to be targeted, and bolt tightening. Loosening device 29, stud tensioner 30, nut attaching / detaching device 31, and nut transfer device 32
Are collectively arranged.

As shown in FIG. 3, the copying device 27 is mainly provided with a sleeve body 34 that is hung from an elevating frame 25 and has an inner diameter that surrounds the stud bolt 4, and the sleeve body 34.
34 and a copying roller 35 rotatably provided. The sleeve body 34 is sequentially inserted deep into the stud bolt 4 in the axial direction when the elevating frame 25 is lowered. Further, the copying rollers 35 are arranged at 90 ° intervals so as to surround the stud bolt 4 from the outside in the radial direction, and are also provided as a set of upper and lower parts at a considerable interval in the axial direction of the stud bolt 4. When the elevating frame 25 is lowered, the copying device 27 is moved by the stud bolt 4 when the sleeve body 34 is inserted into the stud bolt 4 and the copying roller 35 axially travels on the outer peripheral surface of the stud bolt 4. The lifting / lowering movement of the lifting / lowering frame 25 is adjusted and guided from the side of the sleeve body 34 where the movement is restricted. As a result, the bolt cleaning device 28 or the like arranged on the elevating frame 25 is guided to the stud bolt 4 to be worked. At this time, the position of the elevating frame 25 may slightly move from the position when the rotary table 17 is stopped, but this can be absorbed by the swinging of the elevating frame 25 by attaching the expansion / contraction means 26 described above. There is. Further, between the bolt cleaning device 28 and the stud tensioner 30, an auxiliary roller 36 is provided so as to be supported by any of them via a bracket or the like. These auxiliary rollers
The 36 is mounted in a tubular housing 37 surrounding the stud bolt 4 so that the stud bolt 4 is sandwiched in the radial direction of the upper lid flange 5 by being deflected by 45 ° with respect to the copying roller 35. These auxiliary rollers 36 run along the axial direction on the outer peripheral surface of the stud bolt 4 at a considerable distance from the copying roller 35 due to the lowering of the elevating frame 25, and the elevating frame 25 has a diameter of the upper lid flange 5. By restricting the swaying in the direction, the copying accuracy by the copying roller 35 is improved.

Next, the stud tensioner 30 assembled together will be described.

The stud tensioner 30 is for adding a tensioner to the stud bolt 4 when tightening or loosening the nut 7 to the stud bolt 4 to reduce the torque required to secure or loosen the fastening force of the nut 7.
To attach and detach the nut, the nut 7 loosened using the stud tensioner 30 is further removed to the top of the stud bolt 4, or the nut 7 is tightened onto the stud bolt 4 from the top of the stud bolt 4 to the upper cover flange 5. It is for screwing to the side.

As shown in FIGS. 1, 2, and 4, the elevating frame 25 is provided with a stud tensioner 30 that hangs from the elevating frame 25.

The stud tensioner 30 has a general configuration, and is mainly extended inward of the cylindrical tensioner housing 38 vertically installed on the elevating frame 25 so as to be vertically movable from the elevating frame 25 side to the upper lid flange 5 side. A sleeve body 42 having a grip portion 39 for gripping the top of the stud bolt 4 formed at the lower end and an engagement collar 41 for engaging the hydraulic piston 40 formed at the upper end.
And a hydraulic piston 40 that pushes the engaging flange portion 40 of the sleeve body 42 upward. The hydraulic piston 40 pushes the sleeve body 42 upward by hydraulic pressure to add a tensioner to the stud bolt 4. ing. Further, the tensioner housing 38 is provided with nut rotating means 43 for engaging the nut 7 and rotating the nut 7 in order to move the nut 7 along the axial direction of the stud bolt 4 in order to tighten and loosen the stud bolt 4. . This nut rotation means 43
Is a socket 45 that is provided coaxially with the stud bolt 4 in the tensioner housing 38 and that engages with an engagement step portion 44 formed on the upper surface of the nut 7, and a gear 46 formed on the peripheral side portion of the socket 45. A gear train 47 that meshes with each other, and a forward-reverse rotation motor that is connected to and drives the gear train 47.
Composed of 48 and. And this nut rotation means 43 is
The motor 45 drives the socket 45 to rotate to tighten and loosen the nut 7 to the stud bolt 4. On the other hand, in the tensioner housing 38, in order to move the nut rotating means 43 provided therein to constitute a nut attaching / detaching portion in synchronization with the movement of the nut 7 along the axial direction of the stud bolt 4, this tensioner housing 38 is used. A moving means 49 such as a screw jack or a hydraulic cylinder for moving the 38 is provided. The moving means 49 has one end attached to the elevating frame 25 and the other end attached to the tensioner housing 38, and moves the tensioner housing 38 up and down with respect to the elevating frame 25. Then, first the stud tensioner 30 is used to loosen the nut 7 by the nut rotating means 43, and then the tension is released and the nut rotating means 43 is operated while the nut rotating means 43 is operated to move the tensioner housing 38 by the moving means 49. By raising, the nut 7 can be removed to the top of the stud bolt 4. The tightening of the nut 7 will be performed in the reverse order. By configuring in this way,
The nut 7 can be easily and automatically attached to and detached from the stud bolt 4.

At the upper end of the housing 37 of the auxiliary roller 36, as shown in FIGS. 5 and 6, an elongation measuring device 50 for sitting (grounding) on the upper end of the stud bolt 4 and measuring the amount of elongation is installed. It is provided. That is, the housing 37 of the auxiliary roller 36 constitutes a moving frame for moving the elongation measuring device 50 along the pitch circle of the stud bolt 4.

An extension measuring rod 52 for assisting extension measurement is inserted into the shaft core hole 51 of the stud bolt 4, and the extension measuring device 50 contacts the upper end of the extension measuring rod 52 and extends with the stud bolt 4. Contactor that detects the amount of displacement with the measuring rod 52
53 hangs up and down freely.

In the illustrated example, the elongation measuring device 50 is a gauge head main body 54 having a built-in linear gauge for electrically detecting the movement amount of the contactor 53.
The gauge head body 54 is provided with a contact 53
A cylindrical leg portion 55 that surrounds the stud bolt 4 and is seated on the upper end portion of the stud bolt 4 is attached. The leg portion 55 is vertically hung in the housing 37 through an opening 56 formed in the upper end portion of the housing 37 of the auxiliary roller 36. A bracket 58 having an opening 57 through which the gauge head main body 54 can be vertically inserted is attached to the upper end portion of the housing 37, and a stopper having a nut at the lower end portion is formed on both lower surfaces of the opening portion 57 of the bracket 58. A pair of guide rods 60 to which 59 is attached are attached vertically. A support frame 62 having a shaft hole 61 through which the guide rod 60 is inserted is attached to the gauge head main body 54, and the support frame 62 is urged downward on the guide rod 60 between the support frame 62 and the bracket 58. Spring 63 is installed. As a result, the spring 63 absorbs the amount of extension of the stud bolt 4 and maintains the positional relationship of the gauge head main body 54 from the reference surface of the upper end of the stud bolt 4 constant. The signal cable 64 led from the gauge head main body 54 is connected to an operation panel (not shown) installed at a place distant from the upper lid 2 so that the measured value can be displayed and recorded on the operation panel.

 Next, the operation of the embodiment will be described.

When removing the upper lid 2 of the reactor pressure vessel, first, the fixed base 10 equipped with various devices suspended on a crane or the like is attached to the upper lid 2.
Then, the rotary table 17 is positioned with respect to the bolt pitch circle by descending upward and measuring the gap between this and the outer diameter of the stud bolt 4 by the sensor 71 provided on the pillar 70 to measure and correct the misalignment amount. When the elevating and lowering frame 25 is lowered by the expansion / contraction means 26, the copying device 27 is moved along the stud bolt 4 by the amount of deviation in the rotational direction (pitch), and the rear elevating and lowering frame 25 is lowered following the stud bolt 4. By the lifting control of the copying device 27 and the lifting frame 25, the bolt cleaning device 28 and the like are accurately guided to the stud bolt 4 to be worked.

Then, the work such as cleaning the stud bolt 4 and removing the nut 7 is completed, the upper lid 2 is removed from the body portion, and the upper lid 2 is attached to the body portion again in the reverse order. At the time of this attachment, the upper end of the stud bolt 4 is pulled up by the tensioner 30 and a predetermined tension is applied to the stud bolt 4, and the nut 7 is tightened by the nut rotating means 43. Whether or not the stud bolt 4 is properly tensioned is determined by measuring the amount of elongation of the stud bolt 4 before and after tightening the nut with an elongation measuring device 50. in this case,
The elongation measuring device 50 is provided with the stud bolt 4 when the housing 37 of the auxiliary roller 36 is covered with the target stud bolt 4.
Is seated on the upper end (reference surface) of the through the leg 55, and its contact 53 comes into contact with the upper end of the extension measuring rod 52 in the stud bolt shaft core hole 51 to connect the stud bolt 4 and the extension measuring rod 52. The relative extension displacement between the two is detected as the amount of movement, and the amount of extension of the stud bolt 4 is obtained. In this way, the elongation measuring device 50 is sequentially moved along the pitch circle of the stud bolt 4 to measure the elongation amount of the stud bolt 4. These operations are performed remotely from the exposed area away from the top lid by the operation panel, and the operation panel can display and record the measured values, which is different from the one in which the operator directly measured each value. The measurement work can be carried out safely and promptly.

Although the elongation measuring device 50 is mounted on the housing 37 of the auxiliary roller 36 in the embodiment, the mounting position of the measuring device 50 is not limited to this.

Further, in the embodiment, the bolt cleaning device 28 and the nut transfer device are used.
The present invention is applied to the upper lid opening / closing device provided with 32, and the nut 7
Although the extension measurement of the stud bolt 4 can be performed in parallel with the tightening work of, the movable frame is movably provided along the pitch circle of the stud bolt 4 on the upper lid 2 when there is no upper lid opening / closing device. The elongation measuring device 50 may be supported on the moving frame so that only the elongation of the stud bolt 4 is measured.

[Advantages of the Invention] Since the elongation measuring device is moved along the pitch circle of the stud bolt to sequentially measure the elongation amount of the stud bolt, it is possible to measure the elongation amount of all the stud bolts on the peripheral portion of the upper lid. It can be performed automatically, which reduces the labor required for measurement, improves safety, and shortens time.

[Brief description of drawings]

FIG. 1 is a side view showing a preferred embodiment of the present invention, FIG. 2 is a plan view thereof, FIG. 3 is a schematic plan view showing a copying state by a copying apparatus, and FIG. 4 shows a stud tensioner and a nut rotating mechanism. Side view, FIG. 5 is a side view of the elongation measuring device, 6th
FIG. 5 is a view taken along the line V-V in FIG. 5, FIG. 7 is a side view showing a general attachment structure of the upper lid, and FIG. 8 is a plan view thereof. In the figure, 2 is an upper lid, 4 is a stud bolt, 37 is a moving frame, 50 is an elongation measuring device, 51 is a shaft core hole, and 52 is an elongation measuring rod.

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁶ Identification number Reference number within the agency FI Technical indication location G21C 17/003 (72) Inventor Takayuki Matsumoto 1 Shinshinarahara-cho, Isogo-ku, Yokohama-shi, Kanagawa Ishikawajima Harima Heavy Industry Co., Ltd. Yokohama No. 1 Factory (72) Inventor Yasuo Goto No. 1 Shin-Nakahara-cho, Isogo-ku, Yokohama-shi, Kanagawa Ishi Kawashima Harima Heavy Industry Co., Ltd. Yokohama No. 1 Factory

Claims (1)

[Claims] 1. An extension measuring rod inserted into a shaft core hole of a stud bolt arranged upright along a peripheral portion of an upper lid,
A moving frame provided movably along the pitch circle of the stud bolt, and a measuring element supported by the moving frame and in contact with the upper end of the extension measuring rod, and seated on the upper end of the stud bolt. An elongation measuring device for a stud bolt, which is equipped with an elongation measuring device.