JPH0133798B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a nuclear reactor containment vessel internal inspection device that performs maintenance and inspection of various equipment within the reactor containment vessel.

In general, a nuclear reactor at a BWR nuclear power plant consists of a reactor pressure vessel that contains the reactor core and coolant, a reactor shield that shields radiation from the reactor, and a reactor shield that is installed around the reactor pressure vessel. various piping, valves,
These devices are housed inside the reactor containment vessel.

The reactor containment vessel has an airtight structure in order to prevent the release of more than permissible radioactivity into the environment in the event that piping or other equipment is damaged or a coolant loss accident occurs.

The various piping, valves, and equipment inside the reactor containment vessel are designed and manufactured to maintain special reliability compared to general industrial equipment, but they cannot be monitored at all for 6 to 9 months during reactor operation. Not having one is unsettling,
The demand for regular monitoring is increasing among nuclear reactor operators. Additionally, in the event of an accident, it may be difficult to determine how to proceed with future operations based solely on the information from the measuring instruments installed inside the reactor containment vessel. There is also a desire to obtain.

Based on these requirements, the inside of the reactor containment vessel is
Unmanned inspection equipment is being developed that carries various inspection equipment such as TV cameras, thermometers, dosimeters, and microphones and travels unmanned to electronically transmit various information at necessary locations to the outside.

However, the inside of the reactor containment vessel is at a temperature of 60°C during normal reactor operation, and during an accident the temperature rises to approximately 170°C, albeit for a short time. This poses difficult problems that require frequent inspection of unmanned inspection equipment. In particular, as mentioned above, the reactor containment vessel must be kept airtight from the external environment under any conditions, and during reactor operation, it is exposed to radiation levels that cannot be accessed by workers, thus maintaining the reliability of inspection equipment. There was also a problem.

In view of these points, the present invention enables inspection of many necessary inspection parts of the reactor containment vessel, and maintains the inspection vehicle that moves inside the reactor containment vessel while maintaining the airtightness of the containment vessel even while the reactor is operating. The purpose of the present invention is to provide a device for inspecting the inside of a nuclear reactor containment vessel.

Hereinafter, one embodiment of the present invention will be described with reference to FIGS. 1 to 5.

In FIG. 1, reference numeral 1 denotes a pressure vessel containing a reactor core and coolant, and the lower part of this pressure vessel 1 is covered with a reactor shielding wall 2 that shields radiation. The wall 2 is housed within the reactor containment vessel 3.

Piping, valves, and various equipment (not shown) are arranged between the pressure vessel 1 and the reactor containment vessel 3.

Loop-shaped running rails 4a and 4b are arranged above and below between the pressure vessel 1 and the shielding wall 2, and the inspection vehicle 5 runs on these rails. The inspection vehicle 5 is equipped with various measurement devices such as a TV camera, thermometer, and radiation dosimeter, as well as a transmission device that electrically transmits the information captured by these devices to the outside of the containment vessel.

The inspection vehicle 5 is moved by a known chain drive device (not shown) arranged along the travel rails 4a, 4b. The traveling rails 4a and 4b have a substantially horizontal loop shape and are arranged so as to pass near piping, valves, and equipment that require monitoring.

Note that the traveling rails 4a and 4b are arranged with a vertical difference because the object to be monitored is located three-dimensionally within the reactor containment vessel, and further loops can be added as necessary.

An inspection vehicle 5 is located near both traveling rails 4a and 4b.
As shown in FIGS. 2 and 3, this lifting device 6 includes a movable rail 7 that holds the inspection vehicle 5 and a support arm that supports the movable rail 7. 8 and this support arm 8
a guide frame 9 that guides the support arm 8;
The base of the support arm 8 has guide wheels 11, 11.
... 11, it is connected to the guide frame 9 so as to be vertically movable.

The inspection vehicle 5 is suspended on a support frame 12, and rollers 13, 13 are installed in the support frame 12, and the rollers 13 are mounted on the roller bearing surfaces of the movable rails and the running rails 4a, 4b. It is designed to roll on top.

The running rails 4a and 4b form a loop and are separated near the installation of the lifting device, as shown in FIG. 2, and the movable rail 7 is inserted into this portion.

It goes without saying that the length of the separated portion of the running rails 4a, 4b, that is, the movable rail 7, is greater than the longitudinal dimension of the inspection vehicle.

Although not shown, a limit switch or the like is provided to stop the movable rail 7 when it aligns with the running rail 4a or 4b.

The reactor containment vessel 3 is provided with an airtight chamber 14 that temporarily accommodates the inspection vehicle 5, and this airtight chamber 14 is located at the same height as either of the running rails 4a, 4b (Fig. 4, Figure 5).

The airtight chamber 14 has airtight doors 14a and 14b on the inside and outside of the containment vessel, respectively, and inside, a horizontally movable movable rail 15 is attached to the ceiling wall 14c of the airtight chamber via arms 16, 16, 16. It is supported horizontally movably by support rollers 17, 17, 17. The horizontal movement of the movable rail 15 is carried out by a rack 18 provided on the movable rail 15, a pinion 19 attached to the ceiling wall 14c, and a drive device 20 consisting of an electric motor and a gear device for rotationally driving the pinion 19. It's getting old.

The movable rail 15 is configured to be connected to the running rail 4a as shown in FIG. 5 after opening the airtight door 14a, and connecting portions 15a and 15b are attached to the front and rear of the movable rail 15. This connecting portion 15a is selectively connected to an end of a running rail 4a facing toward the airtight door near the airtight door 14a and an end of a running rail 21 provided outside the reactor containment vessel. ing.

Next, the operation of the present invention will be explained.

The inspection vehicle travels on the traveling rails 4a and 4b by itself or by an external drive means such as a chain, and uses on-board equipment to transmit the status of piping, valves, and various equipment inside the reactor containment vessel to the outside of the containment vessel. The inspection vehicle 5 can be moved to either of the running rails 4a, 4b via the lifting device 6.

That is, if the inspection vehicle 5 is currently on the running rail 4a and wants to move from there to the running rail 4b,
The inspection vehicle 5 is moved onto the movable rail 7, the support arm 8 is raised by the hoisting winch 10, and the movable rail 7 is aligned with the position of the traveling rail 4b.

Next, when carrying out the inspection vehicle 5 outside, the inspection vehicle 5 is moved to the running rail 4a that can be connected to the airtight room 14, and is moved to the tip of the running rail near the airtight door 14a. Next, the airtight door 14b is opened and the movable rail 1 is driven by the drive device 20.
5 is projected into the storage container and connected to the tip of the traveling rail (state shown in FIG. 5). Thereafter, the inspection vehicle 5 is moved onto the movable rail, the movable rail 15 is stored in the center of the airtight chamber 14, and the airtight door 14a is closed (the state shown in FIG. 4). Next, if the inside of the airtight chamber 14 is replaced with clean air, the airtight door 1 can be opened from the outside of the containment vessel.
4b can be opened to approach the inspection vehicle 5, and maintenance and inspection of the inspection vehicle 5 can be performed.

Furthermore, when the inspection vehicle 5 is taken out of the airtight chamber 14, the movable rail 15 may be connected to the traveling rail 21 outside the containment vessel.

As explained above, in the present invention, the running rails 4a and 4b installed in a loop shape allow the inspector to approach almost the entire area inside the containment vessel 3, and the inspector can approach any of the running rails 4a and 4b. The inspection vehicle 5 can be moved by the lifting device 6, making it possible to three-dimensionally monitor the entire area inside the reactor containment vessel, and by installing the airtight chamber 14, the inside of the reactor containment vessel can be kept airtight. The inspection vehicle 5 can be taken out of the containment vessel, and by installing the lifting device 6, only one traveling rail can be connected to the airtight door, eliminating the need for an airtight chamber corresponding to each traveling rail. be effective.

[Brief explanation of drawings]

FIG. 1 is an explanatory diagram showing the overall configuration of the reactor containment vessel internal inspection device of the present invention, FIG. 2 is a diagram showing the configuration of the internal lifting device of the inspection device of the present invention, and FIG. 3 is a side view of the lifting device. 4 is a sectional view of the inner airtight chamber constructed according to the present invention, and FIG. 5 is an explanatory view of the operation of the airtight chamber. 1...Pressure vessel, 3...Reactor containment vessel, 4
a, 4b...Traveling rail, 5...Inspection vehicle, 6...
Lifting device, 14...Airtight room.

Claims (1)

[Scope of Claims] 1. A plurality of running rails arranged at different height positions in the reactor containment vessel, an inspection vehicle that rolls on these running rails, and a combined height of at least one of the running rails. An airtight chamber installed with an airtight door that separates the inside and outside of the reactor containment vessel wall at the location, and an airtight room through which inspection vehicles can enter and exit the reactor containment vessel wall while maintaining airtightness. A configuration in which a movable rail provided in the room, a drive device for moving the movable rail in and out, and a running rail in the airtight room and the section immediately adjacent to the airtight room are not provided, and the airtight room is installed in that section and the airtight door can be opened and closed. A nuclear reactor containment vessel interior inspection device characterized by: 2 Traveling rails 4a, 4b from which partial sections of the plurality of traveling rails are removed at multiple locations in the vertical direction
2. The reactor containment vessel internal inspection device according to claim 1, further comprising a cutout section between the two and a lifting device for moving the inspection vehicle up and down in the cutout section.