JPH0643288A - Shearing device for nuclear fuel - Google Patents

Abstract

PURPOSE:To prevent the shear powder from being accumulated in a fuel magazine to interrupt the action of a pusher sizing/feeding a nuclear fuel assembly when the nuclear fuel assembly is sheared by the shearing device of a nuclear fuel. CONSTITUTION:A fuel shearing device shears a nuclear fuel assembly stored in a fuel magazine 3 when it is delivered from the fuel magazine 3 by a pusher 4 reciprocated by a power transfer mechanism 6. The pusher 4 is provided with a deposit removing device (skirt 5) operated by the power transfer mechanism 6, brought into contact with the bottom face of the fuel magazine 3 when advanced, and lifted from the bottom face of the fuel magazine 3 when retreated.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a nuclear fuel shearing device for shearing spent nuclear fuel.

[0002]

2. Description of the Related Art A conventional nuclear fuel shearing device is shown in FIG. This device stores a spent nuclear fuel assembly 2 in a fuel magazine 3 having a rectangular cross section,
And a pusher 4 that moves forward and backward in the fuel magazine 3 by a power transmission mechanism 6 such as a ball screw, sends out the nuclear fuel assembly 2 from the fuel magazine 3 at a fixed pitch, and In the fuel shearing section 1, the nuclear fuel assembly 2 is sheared into small pieces having a constant length. In addition, 4 a in FIG. 4 is a wheel of the pusher 4 mounted on the bottom surface of the fuel magazine 3.

[0003]

In the conventional nuclear fuel shearing device, the nuclear fuel assembly 2 which is fed by the fuel shearing section 1 as described above is sheared, but the metal and the fuel generated during the fuel shearing are used. Debris, sheared powder, etc. fall on the bottom surface of the fuel magazine 3 to form the deposit A, and the pusher 4 sending at a fixed pitch while partially covering the nuclear fuel assembly rides on this deposit A and fuel deposit 3 It may get stuck between the upper lid and the bottom surface, making it inoperable and unable to operate.

The present invention is intended to provide a nuclear fuel shearing device which can solve the above problems of the conventional device.

[0005]

SUMMARY OF THE INVENTION The present invention relates to a nuclear fuel shearing device for shearing a nuclear fuel assembly housed in a fuel magazine by sending it out from a fuel magazine by a pusher that moves forward and backward by a power transmission mechanism. The pusher is provided with a deposit removing device which is operated by a power transmission mechanism, contacts the bottom surface of the fuel magazine when moving forward, and rises above the bottom surface of the fuel magazine when moving backward.

[0006]

In the present invention, when the pusher advances toward the nuclear fuel assembly by the power transmission mechanism, the deposit removing device contacts the bottom surface of the fuel magazine, and at the same time as the pusher advances, metal and fuel fragments / shear powder And the like are removed.

On the other hand, when the busher is moving backward, the deposit removing device rises above the bottom surface of the fuel magazine and does not pull the rest of the deposit backward.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described with reference to FIGS. The main bodies of the fuel assembly 2, the fuel magazine 3 and the pusher 4 in this embodiment are the same as those of the conventional device shown in FIG.

The power transmission mechanism 6 such as a ball screw, which is connected to the pusher 4 having a hollow inside, has a vertical through hole 6a, and the pin-shaped portion 10 projecting downward of the pusher 4 has the through hole 6a. 6a, a gap is formed between the through hole 6a and the pin-shaped portion 10, and its tip (end on the nuclear fuel assembly side) contacts the pusher 4 when the power transmission mechanism 6 advances. It is like this. An arm 8 extending in the pusher 4 is attached to the tip of the power transmission mechanism 6.
A skirt 5 slidably attached to the pusher 4 by a pin 9 and extending forwardly and downward in the pusher 4 is pivotally attached to the tip of the arm 8. This skirt 5, as shown in FIG. 1 (b),
A lower portion 5a that protrudes below the pusher 4 and extends over the entire width of the pusher 4 is provided below the pusher 4. Reference numeral 7 is a spring provided so as to surround the arm 8, one end of which is attached to the arm 8 and the other end of which is attached to the pusher 4.

In this embodiment, as shown by the arrow B in FIG. 1, when the pusher 4 is moved forward by the power transmission mechanism 6, the arm 8 is moved forward against the pusher 4 in the direction of the arrow b against the spring 7. 1 (left in FIG. 1), the skirt 5 rotates around the pin 9 in the counterclockwise direction as shown by the arrow b ', and the lower portion 5a of the skirt 5 is moved to the fuel magazine 3.
As shown in FIG. 3, the deposit A such as the shearing powder is removed at the same time as the pusher 4 is moved forward in contact with the bottom surface of the pusher 4.

On the other hand, as shown by the arrow C in FIG. 2, when the pusher 4 is retracted by the power transmission mechanism 6, the protrusion 7 of the pusher 4 and the power transmission mechanism 6 are moved by the spring 7.
The arm 8 is rearward with respect to the pusher 4 in the direction of the arrow c by the distance corresponding to the clearance A of the through hole 6a (rightward in FIG. 3).
And the skirt 5 pivots around the pin 9 in the clockwise direction as indicated by the arrow c ′, the tip of the skirt 5 rises apart from the bottom surface of the fuel magazine 3, and the pusher 4 moves back when the pusher 4 retracts. The rest of the deposit A is prevented from being pulled backward.

[0012]

As described above, according to the present invention, by providing the deposit removing device which comes into contact with the bottom surface of the fuel magazine when moving forward and rises above the bottom surface of the fuel magazine when moving backward,
It is possible to remove shear fragments and shear powder generated during shearing of the nuclear fuel assembly, prevent its accumulation, improve the operational reliability of the pusher, and improve the shear efficiency of nuclear fuel and the efficiency of subsequent processes. You can

[Brief description of drawings]

FIG. 1 shows an embodiment of the present invention, FIG. 1 (a) is an elevational view showing a state of a main part of the pusher when it is advanced, and FIG.

FIG. 2 is an elevational view showing a state of the essential part of the embodiment when the pusher is retracted.

FIG. 3 is an explanatory diagram of a deposit removal state of the embodiment.

FIG. 4 is a vertical sectional view of a conventional nuclear fuel shearing device.

[Explanation of symbols]

 1 Fuel Shear Part 2 Fuel Assembly 3 Fuel Magazine 4 Pusher 5 Skirt 5a Lower part of Skirt 6 Motion Transmission Mechanism 6a Through Hole 7 Spring 8 Arm 10 Pin-shaped Part A Deposit

Claims (1)

[Claims] 1. A nuclear fuel shearing device in which a nuclear fuel assembly housed in a fuel magazine is sent out from a fuel magazine by a pusher that moves forward and backward by a power transmission mechanism to shear the nuclear fuel assembly. A shearing device for a nuclear fuel, wherein a pusher is provided with a deposit removing device which is sometimes in contact with a bottom surface of the fuel magazine and which rises from the bottom surface of the fuel magazine when retracted.