JPH0985208A - Cleaning device for vertical-type vapor generating device and expansion arm therefor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a small and smoothly operating cleaning device capable of removing and cleaning sludge on the pipe support plate of a shell and tube heat exchanger-type vapor generating device. SOLUTION: This cleaning device 20 for cleaning the interior of a vertical- type vapor generating device is composed of a guide rail 21 to be inserted into the vapor generating device through its inspection hole, a freely dipping and inclining lifting gear 30 freely traveling on a guide rail 21, an expansion arm 40 mounted on the lifting gear 30 and actuated to be foldable and pivotally movable, a feed device 25 installed on the front end of the expansion arm 40, and a flexible arm 40 and fed by a feed device 25.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a device for remotely cleaning the inside of a steam generator having a complicated internal structure such as a tube-type heat exchanger.

[0002]

2. Description of the Related Art For example, a vertical steam generator used in a pressurized water nuclear reactor is a type of tubular heat exchanger having a heat transfer tube bundle surrounded by a wrapper tube, Sludge easily accumulates in the body-side space where the water supply flows. The structure of the lower part of the steam generator will be described with reference to FIGS. 6 and 7. The tube plate 3 is integrally joined to the lower part of the body 1 and a large number of heat transfer tube bundles 5 are formed on the tube plate 3. The ends of the heat tubes 7 are connected. The heat transfer tube bundle 5 is surrounded by the wrapper tube 9,
An intermediate portion of each heat transfer tube 7 is horizontally supported by tube support plates 11 arranged at intervals in the vertical direction. In a typical example, the heat transfer tube 7 is an inverted U-shaped tube, and the heat transfer tube bundle 5 has a dead space corresponding to the minimum bending radius in the central portion, but the tube support plate 11 has a notch 13 at this portion.
Are formed.

Conventionally, it is considered that the sludge is most accumulated on the tube sheet 3, and a telescopic multi-stage telescopic rod is inserted from the inspection hole 15 of the body 1 and high pressure washing water is supplied from the nozzle at the tip thereof. The sludge that was ejected and accumulated around the base of the heat transfer tube 7 was washed away.

[0004]

However, when the steam generator as described above is used for a long time, the lowermost tube sheet 3 is used.
A large amount of sludge accumulated not only on the upper surface of the pipe but also on the upper pipe support plate 11, and it became necessary to wash and remove the sludge. However, sludge removal on the tube support plate could not be physically realized by the method of inserting the multi-stage telescopic rod through the inspection hole near the tube plate as described above. Further, the outer shell of the steam generator is a kind of pressure resistant container, and it is not realistic to provide a large number of inspection holes corresponding to the upper tube support plates due to the presence of a wrapper tube surrounding the heat transfer tube bundle. It was Therefore, the vertical steam generator cleaning device can be inserted from the inspection hole close to the tube plate, can clean the sludge on the upper tube support plate, is small in size, has good operability, and can be easily taken out in the event of a failure and has an excellent escapeability. Was required. The present invention has been made to meet the above-mentioned conventional needs and needs.

[0005]

In order to solve the above-mentioned problems, a vertical steam generator cleaning apparatus according to the present invention has a guide rail which can be inserted through an inspection hole of the steam generator and movable on the guide rail. A lifting device that can be raised and lowered, a telescopic arm that can be bent and pivoted at the upper end of the elevating device, a feeding device that is provided at the front end of the elongating device, and a movable device along the elevating device and telescopic arm In addition, it is composed of a flexible cleaning liquid feeding / spouting zone which is fed by the feeding device. The telescopic arm is preferably a fixed portion fixed to the upper end of the lifting device, a swivel portion pivotally connected to the fixed portion via a pin, a pivot cylinder integrally fixed to the fixed portion, and It is composed of a pivoting wire interposed between the pivoting cylinder and the revolving part, and the revolving part is provided with a telescopic cylinder which separates a front end portion supporting the feeding device from each other. More preferably, a lifting wire mechanism for lifting the flexible cleaning liquid feeding / spouting band from the upper end of the lifting device to the rear end of the telescopic arm is provided along the lifting device to reduce the load on the feeding device. In a preferred embodiment, the pivoting wire includes a thermoplastic resin connecting portion and a heating heater wire for cutting, which can be cut in an emergency such as a failure and improves emergency escape properties.

[0006]

DETAILED DESCRIPTION OF THE INVENTION Embodiments of the present invention will be described below with reference to the accompanying drawings. FIG. 1 shows the cleaning device 20 according to the present invention in a position in which it enters the steam generator and is ready for a cleaning operation. In the figure, the guide rail 21 passing through the inspection hole 15 shown by the chain double-dashed line is supported by a suitable gripping device that serves as the base of the entire cleaning device 20 but remains outside the steam generator. The guide rail 21 is movably mounted on the lifting device 3
No. 0 is supported, which comprises a running part 31 and an elevating / contracting part 33 pivotally connected to the running part 31. The depression / extension part 33
When passing through the inspection hole 15, it lies down on the guide rail 21, is pivoted and stands inside the steam generator as shown in the drawing, and penetrates the notch 13 of the tube support plate. The up-and-down stretchable portion 33 has a normal multi-stage stretchable structure and can move up and down the upper end portion. A holding mechanism 35 is provided on the side of the tip of the depression-extension part 33. The holding mechanism 35 is of a heat transfer tube clamp type, and is for stabilizing the turning operation and the feeding operation of the flexible insertion band, which will be described later. Further, a pivotable telescopic arm 40 is attached to the upper end of the elevation / extension part 33, and a feeding device for feeding the flexible insertion band 23, which is a flexible cleaning liquid feeding / ejection band, between the heat transfer tubes 7 at the front end of the extension / contraction. 25 are provided. Flexible insertion band 2
A flexible hose 3 for sending high-pressure washing water, a linear member for remotely visually observing the insertion tip portion, and the like are formed in a thin strip shape, and have a washing water ejection port at the tip portion.

The detailed construction of the pivotable telescopic arm 40 is shown in FIGS. In these figures, the fixed portion 41 and the swivel portion 43 are connected by a support pin 45 so as to be bendable and pivotable, and in order to minimize the pivot (swirl) required torque of the swivel portion 43, the support pin 45 is Telescopic arm 40
It is located in the central part of. An air cylinder 47 for pivoting the swivel portion 43 is integrally or fixedly provided on the fixed portion 41 having a U-shaped cross section. The air cylinder 47 may be a hydraulic cylinder, but it is attached as described above and fixed to the fixing portion 4.
The rigidity of 1 is raised. A piston rod 49 of the air cylinder 47 as shown in FIG.
Are not directly connected to the turning portion 43, but are connected via the wire 51. When the piston rod 49 is pulled in by connecting with the wire 51 in this way,
As shown in FIGS. 6B and 6C, the swivel portion 43 pivots around the support pin 45 and is bent 90 degrees. On the other hand, when the air cylinder 47 is operated so as to push out the piston rod 49, the head of the piston rod 49 comes into contact with the swivel portion 43, and the swivel portion 43 is pivoted in the counterclockwise direction (in the figure) to move the piston rod 49 as shown in FIG. Return to the state of (a). By using the wire 51 in this way, a flexible connection is achieved.

Further, the swivel portion 43 is provided with a two-stage hydraulic cylinder 53 and a guide mechanism 55 parallel to the two-stage hydraulic cylinder 53 extending in the longitudinal direction, and further, the hydraulic cylinder 53 and the guide mechanism 5 are provided.
5 is vertically offset as shown in FIG.
The rigidity of the turning portion 43 is increased. The expansion / contraction amount of the hydraulic cylinder 53 can be remotely measured by measuring with the ultrasonic sensor 57, and the expansion / contraction amount is controlled by providing a flow rate control circuit of the supply water outside the distant steam generator. ing.

A pulley 59 of a lifting wire mechanism is provided at a rear end portion opposite to a front end portion to which the feeding device 25 is attached, and a lifting wire 61 is wound around the pulley 59, and the wire 61 is moved up and down. It extends to the depression / extension part 33 of the device 30. The wire 61 lifts the flexible insertion band 23 and the tubes attached to the flexible insertion band 23 fed from the feeding device 25. This reduces the load on the feeding device 25 and facilitates miniaturization. Further, by guiding the wire 61 to the outside of the steam generator along the guide rail 21 and the like,
It functions as a collecting means for the swiveling part 43 when the air cylinder 47 fails. Reference numeral 63 is a recovery mechanism for the flexible insertion band 23, which transmits the output to the flexible insertion band 23 and recovers it. The air cylinder 47 that pivots the swivel unit 43 (swirls within a range of about 90 degrees) is fixed, and it becomes difficult to pivot the swivel unit 43 even if the wire 61 is used.
In the case where it is difficult to recover the wire, the wire 51 is provided with a thermoplastic resin connecting portion, and the connecting portion can be remotely melt-cut. When the melt cutting is performed, the swiveling part 43 is free with respect to the fixed part 41, so that the recoverability, that is, the emergency escape property is improved. On the other hand, by providing a visual camera at the rear end of the revolving unit 43, the condition before pivoting, the operating condition of the holding mechanism 35, and the condition after pivoting can be remotely observed.

In order to bring the cleaning device 20 having the above structure into the steam generator through the inspection hole 15, the telescopic arm 40 is shortened and the fixed part 41 and the swivel part 43 are arranged as shown in FIG. 4 (a). Is made linear, and the elevation / expansion / contraction portion 33 of the lifting device 30 is further laid down to make the state shown in FIG. Then, the elevating and retracting portion 33 is pivoted into a vertical posture, the telescopic arm 40 is passed through the notch 13, and then the swivel portion 43 is pivoted into a posture as shown in FIG. Is moved to a target position, the flexible insertion band 23 is inserted between the heat transfer tubes 7, and cleaning is performed. In order to take the cleaning device 20 out of the steam generator, the above-mentioned procedure may be traced back.

[0011]

As described above, since the cleaning device according to the present invention has the guide rail, the elevating device for freely moving up and down, and the telescopic arm for freely bending and pivoting, it is inserted through the inspection hole near the tube plate of the steam generator. However, the upper pipe support plate can be accessed, and the sludge can be washed and removed by inserting the flexible cleaning liquid feeding / spouting zone between the heat transfer pipes by the feeding device. Further, since the swivel portion and the fixed portion constituting the telescopic arm are connected by the combination of the pivoting cylinder wire, the rigidity of both can be increased and the escapeability in an emergency can be improved.

[Brief description of drawings]

FIG. 1 is an overall perspective view of a cleaning device 20 according to an embodiment of the present invention.

FIG. 2 is a telescopic arm 40 that is a main part of an embodiment of the present invention.
FIG.

FIG. 3 is a sectional view taken along line III-III in FIG.

FIG. 4 is an explanatory view of the operation in the embodiment.

FIG. 5 is an explanatory view of the operation of the telescopic arm 40.

FIG. 6 is a partial vertical cross-sectional view of a steam generator to be cleaned by the cleaning device according to the present invention.

FIG. 7 is a partial plan sectional view of a steam generator to be cleaned by the cleaning device according to the present invention.

[Explanation of Codes] 20 Cleaning Device 21 Guide Rail 23 Flexible Insertion Band 25 Feeding Device 30 Elevating Device 31 Traveling Part 33 Lifting / Expanding Part 40 Expanding Arm 41 Fixing Part 43 Swiveling Part 45 Support Pin 47 Air Cylinder 51 Wire 53 Hydraulic Cylinder 57 Ultrasonic sensor 59 Pulley 61 Wire

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Seiichi Morimoto 1-1-1, Wadasaki-cho, Hyogo-ku, Kobe-shi, Hyogo Prefecture Mitsubishi Heavy Industries, Ltd. Kobe Shipyard (72) Inventor Mitsuo Kuwahara Hyogo-ku, Kobe-shi, Hyogo 1-1-1 Wadazakicho Mitsubishi Heavy Industries Ltd. Kobe Shipyard

Claims (8)

[Claims] 1. A guide rail that can be inserted through an inspection hole of a steam generator, a lifting device that can move on the guide rail and can be raised and lowered, and a telescopic arm that is provided on an upper portion of the lifting device and that can bend and pivot. The feed device provided at the front end of the telescopic arm, the elevating device, and the flexible cleaning liquid delivery spouting zone that is movable along the telescopic arm and is delivered by the delivery device. Type steam generator cleaning device. 2. The lifting wire mechanism for lifting the flexible cleaning liquid feeding / spouting zone from the upper end of the lifting device to the rear end of the telescopic arm is provided along the lifting device. Vertical steam generator cleaning device. 3. A fixed part fixed to the upper end of the lifting device, a swivel part pivotally connected to the fixed part via a pin, a pivot cylinder integrally fixed to the fixed part, and the same. The telescopic arm is composed of a pivoting wire interposed between a cylinder and the revolving unit, and the revolving unit includes a telescopic cylinder that separates and closes a front end portion that supports the feeding device. The vertical steam generator cleaning device according to claim 1. 4. The vertical steam generator cleaning apparatus according to claim 3, wherein the pivoting wire includes a thermoplastic resin connecting portion and a cutting heater wire. 5. An ultrasonic sensor for measuring the expansion / contraction amount of the expansion / contraction cylinder is provided on the swivel part of the expansion / contraction arm, and the flow control circuit for the expansion / contraction cylinder is provided separately from the expansion / contraction arm. Item 3. The vertical steam generator cleaning device according to Item 3. 6. A swivel unit having a telescopic cylinder, a fixed unit pivotally connected to a longitudinal center of the swivel unit via a pin, a pivot cylinder integrally fixed to the fixed unit, and A telescopic arm for a vertical steam generator cleaning device, comprising a pivoting wire interposed between the cylinder and the swivel part. 7. The telescopic arm for a vertical steam generator cleaning device according to claim 6, wherein the pivoting wire includes a thermoplastic resin connecting portion and a cutting heater wire. 8. The telescopic arm for a vertical steam generator cleaning device according to claim 6, wherein an ultrasonic sensor for measuring the telescopic amount of the telescopic cylinder is provided in the swivel portion.