JPH0736097U - Grasping tool for nuclear fuel assembly - Google Patents

Abstract

(57) [Summary] [Purpose] To provide a lightweight and compact nuclear fuel assembly gripping tool having a short overall length. [Structure] The gripping tool (10) is fixed to the upper plate (12) including a lifting part (14) to which a wire rope of a fuel hoisting device, for example, a hoisting machine, is attached in the reactor building, and is fixed to the upper plate and spaced from each other. A pair of side plates (1
8) and a hook (22) pivotally mounted between the side plates for engaging the fuel handle of the fuel assembly, and operatively connected to the hook for setting the hook between a fuel handle gripping position and a release position. A pneumatic cylinder (26) arranged to pivot between. The pneumatic cylinder (26) is provided upward through the opening (32) provided in the upper plate (12), thus the grip has a short overall length and is lightweight and compact.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 TECHNICAL FIELD The present invention relates generally to an improved grip for a nuclear fuel assembly, and more particularly to an improved grip for an irradiated fuel assembly for a boiling water reactor (hereinafter "BWR").

[0002]

[Prior art]

 When performing refueling work in water at a boiling water nuclear power plant or when moving spent fuel in a fuel pool (these works are performed at a depth of 3 to 10 m below the water surface), conventionally, as shown in FIG. The fuel assembly grip 1 as shown in FIG. 5 is used. Such a conventional gripper 1 is generally connected to a fuel lifting device that is movable on the operation floor in the reactor building, for example, a hook of a reactor building overhead crane or a wire rope of a hoist of a refueling platform. An upper plate 3 including an extending lifting rod portion 2 and an inverted funnel shape fixed to the upper plate and spaced apart from each other, each receiving a lateral fuel handle of a fuel assembly C or a bail V. A pair of depending side plates 5 with notches 4 and hooks or hooks 7 attached to the side plates so that they can pivot about an axis 6 to engage the fuel handle in the notches in the side plates; A pneumatic cylinder 8 operatively connected to the fuel handle for pivoting the hook between a fuel handle grip position and a fuel handle release position, the cylinder side of the pneumatic cylinder being an upper plate. A shaft 9 extending between the lower surface or the side plate, the piston side is connected pivotally each hook.

[0003]

[Problems to be solved by the device]

 The conventional grip has a drawback that it is poor in operability because its entire length, that is, the distance between the top end of the lifting portion 2 of the upper plate and the bottom end of the side plate 5 is about 60 cm or more, and it is relatively long and heavy. .

An object of the present invention is to provide an improved gripping tool having a short overall length, a lightweight and compact structure, and improved operability.

[0005]

[Means for Solving the Problems]

 According to the present invention, an upper plate including a lifting portion associated with a fuel lifting device, a pair of side plates fixed to the upper plate and spaced from each other, and pivotally mounted between the side plates. A grip for engaging the fuel handle of the fuel assembly and an actuator operatively coupled to the hook and arranged to pivot the hook between a fuel handle grip position and a release position. With respect to the tool, the actuator is provided with a grip having a short total length and is provided upward through an opening provided in the upper plate so as to be lightweight and compact.

Preferably, the actuator is a pneumatic cylinder, the cylinder side of which is pivotally connected to the lifting portion of the upper plate and the piston side of which is pivotally connected to the hook.

[0007]

【Example】

 Referring to FIGS. 1 and 2, a fuel assembly gripper according to the present invention, generally indicated at 10, is shown in a schematic elevation view. The structure of the main components of the gripper 10 is almost the same as that of the conventional one, and thus detailed description thereof will be unnecessary.

Reference numeral 12 designates an upper plate, and 14 designates a rod-shaped hoisting portion that is fixed to approximately the center of the upper plate and extends upward. Alternatively, a hole 16 is provided for operatively engaging a wire rope (not shown) of the hoist. Reference numeral 18 denotes a pair of hanging side plates fixed to the upper plate 12 at intervals, and the lower part of each side plate is a reverse handle adapted to receive a fuel handle or bail 28 fixed to the upper tie plate of the nuclear fuel assembly. A funnel-shaped notch 20 is provided. 22 is a pivotable hook around a support shaft 24 extending between the side plates 18 and 26 is remotely actuated to indicate an actuator that pivots the hook 22 between a fuel handle release position and a gripping position. There is. In the preferred embodiment shown, the actuator is a double-acting pneumatic cylinder. Numeral 30 is attached to the outside of each side plate so as to cover the notch 20, and directs a half-hood-like guide which engages the side portion of the fuel handle and guides the fuel handle into the notch 20 of the side plate. ing. The half-hood guide 30 engages with a part of the handle when the grip of the present invention is positioned with respect to the fuel handle and the fuel handle 28 and the notches 20 of the side plates 18 are not aligned. Helps guide the into the notch 20 in the side plate.

According to an important feature of the present invention, as best seen in FIG. 1, the pneumatic cylinder 26 extends upward through an opening 32 in a portion of the upper plate 12. . The cylinder side of the pneumatic cylinder is pivotally attached to a bracket 34 provided on the lifting portion 14, and the piston side is operatively connected to the hook 22 via a shaft pin 36. When the pneumatic cylinder 26 is actuated to extend and retract the piston, the hook 22 may pivot about the shaft 24 between a release position (FIG. 1) and a gripping position (FIG. 3) of the fuel handle 28. it can. Preferably, as shown in FIG. 2, a stop member 38 with which the hook 22 abuts is provided between the side plates.

As shown in FIG. 1, the hook 22 is preferably provided with a forced release trigger member 40. When the spent fuel is moved in the fuel pool using the grip of the present invention, for example, when the pneumatic cylinder 26 fails for some reason and the hook cannot move from the grip position, the worker is on the operation floor. The hook can be forcibly separated from the handle by manually hooking the dedicated trigger engagement pole (not shown) on the trigger member 40 and pulling the hook upward.

The link device 42 is operatively connected to the hook 22 by a method known to those skilled in the art, and whether the hook is in the handle release position or the grip position can be seen from a remote location. It is associated with a hook position indicating mechanism (not shown) that allows the user to distinguish it.

[0012]

[Effect of device]

 As described above, the gripper of the present invention has the actuator associated with the hook penetrating through and above the upper plate, and thus has a short overall length, and thus is lightweight and compact, and thus is easy to handle and operate. The property is improved.

[0013]

[Brief description of drawings]

FIG. 1 is a schematic elevational view of a fuel assembly gripper of the present invention, with the hook shown with the fuel handle open. .

FIG. 2 is a sectional view taken along line II-II in FIG.

FIG. 3 is a partial view showing the hook of the grip of the present invention in the fuel handle grip position.

FIG. 4 is a schematic perspective view showing a usage state of a conventional fuel assembly gripping tool.

5 is a schematic view of the conventional gripping tool shown in FIG. 4 with one side plate removed. FIG.

[Explanation of symbols]

 10 Fuel Assembly Grasping Tool 12 Upper Plate 14 Lifting Part 18 Side Plate 20 Notch 22 Hook 24 Support Shaft 26 Actuator or Pneumatic Cylinder 28 Fuel Handle 32 Opening

Claims (2)

[Scope of utility model registration request] 1. A nuclear fuel assembly including an upper plate including a lifting portion associated with a fuel lifting device, a pair of side plates fixed to the upper plate and spaced apart from each other, and pivotally mounted between the side plates. A hook that engages the fuel handle of the body,
A nuclear fuel assembly gripper operatively coupled to the hook and including an actuator arranged to pivot the hook between a fuel handle gripping position and a release position, the actuator comprising: A gripping tool that is provided upward through an opening provided in the upper plate so as to be short, lightweight and compact in a direction. 2. The gripping tool according to claim 1, wherein the actuator is a pneumatic cylinder, and the cylinder side is pivotally connected to a lifting portion of the upper plate and the piston side is pivotally connected to a hook, respectively.