A grab head and fuel basket center column separation tool and method

Abstract

The application relates to a tool for separating a grab head from a fuel basket center column, which comprises a driving rod, a guide hub, a swing rod, a rotary table, an operating long rod and a pin, the middle part of the rotary table is provided with the guide hub, the end part of the rotary table is provided with the pin, one end of the swing rod is connected with the lower end of the guide hub, the other end of the swing rod is connected with one side of the pin, and the operating long rod is connected with the pin. The separating tool is simple in operation and high in practicability, can realize the separation of the grab head from the fuel basket center column, ensures the safe, efficient and orderly production of dry storage of spent fuel, and provides technical support and reference for subsequent similar power station related projects.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of spent fuel transportation, in particular to a tool and method for separating a grab head from a fuel basket central column. BACKGROUND

[0002] The two heavy water reactor nuclear power units of Qinshan Nuclear Power are the only two heavy water reactor units in China. The advantage of heavy water reactor is that it can be refueled without stopping the reactor. However, due to the limited storage capacity of the refueling pool, a spent fuel temporary dry storage must be built to ensure the stable operation of the heavy water reactor nuclear power plant. The key equipment for dry storage is the spent fuel storage basket. After the fuel basket is filled with 60 rod bundles, it needs to be lifted from the pool transport trolley to the WSW (shielding working compartment). Due to the misalignment between the grab head and the fuel basket central column and other unexpected situations, the grab head and the fuel basket central column cannot be separated, which will cause the permanent storage of the entire equipment and the fuel basket in the pool, and greatly affect the safe production of the spent fuel dry storage. SUMMARY

[0003] Therefore, it is necessary to provide a tool and method for separating a grab head from a fuel basket central column when the grab head and the fuel basket central column cannot be separated, which is simple to operate, practical, can separate the grab head from the fuel basket central column, ensures the safe and efficient production of the spent fuel dry storage, and provides technical support and reference for subsequent similar power plant projects.

[0004] In order to achieve the above purpose, the present application provides the following technical scheme:

[0005] A tool for separating a grab head from a fuel basket central column, comprising a driving rod, a guide hub, a swing rod, a transfer trolley turntable, an operating long rod and a pin, the middle part of the transfer trolley turntable is provided with a guide hub, the end part of the transfer trolley turntable is provided with a pin, one end of the swing rod is connected with the lower end of the guide hub, the other end of the swing rod is connected with one side of the pin, and the operating long rod is connected with the pin.

[0006] Working principle: when the grab head and the fuel basket central column cannot be separated, the fuel basket is first lifted to a corresponding height, then the separation tool is installed, after the installation is completed, the separation tool is placed on the transfer trolley, the transfer trolley is moved to the separation area, the upper end of the driving rod is aligned with the hole of the fuel basket central column, the interface of the operating long rod is inserted on the pin, and the operating long rod is clamped with the pin by rotating the operating long rod, the lower end of the driving rod is inserted into the guide hub, the fuel basket is lowered until the upper end of the driving rod contacts the head of the grab head central rod, the fuel basket and the grab head central rod are completely contacted, the interface of the operating long rod is connected with the pin, and the operating long rod is clamped with the pin by rotating the pin, the operating long rod is pressed downward, the driving rod is driven to move upward, and the steel ball slides downward, so that the grab head and the fuel basket are separated.

[0007] Further, the bottom of the operating long rod is provided with an interface, which is connected with the bayonet.

[0008] Further, the interface is buckled with the bayonet.

[0009] Further, the end of the operating long rod is provided with an operating handle.

[0010] Further, the length of the operating long rod is adjustable.

[0011] Further, the length of the driving rod is adjustable.

[0012] A method for separating a grab head from a fuel basket center column, comprising the following steps:

[0013] 1. lifting the fuel basket from underwater to a shield work station, confirming that the grab head and the fuel basket center column are locked;

[0014] 2. placing the grab head and the fuel basket center column separation tool on a transfer trolley, moving the transfer trolley to a separation area, and aligning the upper end of the driving rod with the fuel basket center column;

[0015] 3. inserting the interface of the operating long rod into the bayonet, and rotating the operating long rod to buckle the operating long rod with the bayonet; inserting the lower end of the driving rod into the guide hub;

[0016] 4. lowering the fuel basket until the upper end of the driving rod contacts the head of the grab head center column;

[0017] 5. confirming that the fuel basket and the grab head center column are in complete contact, pressing down the operating long rod, swinging the rod upward to drive the driving rod upward, thereby moving the grab head center column upward, at this time the steel ball slides down and separates from the fuel basket 4;

[0018] 6. repeating the pressing and lifting of the operating long rod 3mm, until the grab head and the fuel basket are completely separated, then pushing the starting pin and the starting separator on the transfer trolley to completely separate the grab head and the fuel basket; lifting the grab head back to the shield work station for inspection and treatment;

[0019] 7. after the treatment is completed, lowering the grab head, reconnecting the fuel basket to the shield work station, and positioning the transfer trolley in the separation area;

[0020] 8. rotating the operating long rod to separate the operating long rod from the bayonet, and storing the separation tool components.

[0021] The beneficial technical effects of the present application are:

[0022] The grab head and fuel basket center column separation tool and method provided by the application are simple to operate, high in practicability and success rate, can realize separation of the grab head and the fuel basket center column, ensure safe and efficient and orderly production of spent fuel dry storage, and provide technical support and reference for subsequent similar power station related projects. BRIEF DESCRIPTION OF DRAWINGS

[0023] Figure 1 It is a structural schematic diagram of the grab head and fuel basket center column separation tool of the application;

[0024] Figure 2 It is a schematic diagram of the grab head and fuel basket center column separation tool in use.

[0025] Figure 3 It is a position schematic diagram of the transfer trolley.

[0026] In the figure, 1 is a grab head body, 2 is a grab head center rod, 3 is a steel ball, 4 is a fuel basket, 5 is a fuel basket center column, 6 is a driving rod, 7 is a guide hub, 8 is a swing rod, 9 is a transfer trolley turntable, 10 is an operating long rod, 11 is an interface, 12 is a pin, A is a first unloading area, B is a second unloading area, C is a drying area, and D is a separation area. DETAILED DESCRIPTION

[0027] In the description of the application, it should be understood that the terms "left end", "right end", "upper", "lower", "outer side", "inner side" and the like indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings, and are only for the convenience of describing the application and simplifying the description, and do not indicate or imply that the devices or elements referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as a limitation on the application. "Spent fuel pool spent fuel storage transfer trolley" and "transfer trolley" have the same meaning, and "grab head and fuel basket center column separation tool" and "separation tool" have the same meaning.

[0028] The fuel basket is a container for loading high radioactivity nuclear fuel, and has two working modes, one of which is to complete drying, welding, transfer and the like in a shielding workstation, and the other of which is to complete nuclear fuel loading and transfer underwater; the transfer is always through connection of the grab head and the fuel basket center column, the grab head adopts mechanical transmission, the steel ball of the grab head is retracted and ejected (retraction separation and ejection connection), when the grab head appears abnormal during normal operation, the grab head cannot be normally separated from the fuel basket center column, and corresponding separation tools and operation methods are needed to separate the grab head from the fuel basket center column.

[0029] Therefore, the application provides a tool for separating a grab head and a fuel basket center column, comprising a driving rod 6, a guide hub 7, a swing rod 8, a transfer trolley turntable 9, an operating long rod 10 and a pin 12, the middle part of the transfer trolley turntable 9 is provided with the guide hub 7, the end part of the transfer trolley turntable 9 is provided with the pin 12, one end of the swing rod 8 is connected with the lower end of the guide hub 7, the other end of the swing rod 8 is connected with one side of the pin 12, the bottom of the operating long rod 10 is provided with an interface 11, and the interface 11 is connected with the pin 12.

[0030] Working principle: when the grab head and the fuel basket center column cannot be separated, the fuel basket 4 is first lifted to a corresponding height, then the separating tool is installed, after the installation is completed, the separating tool is placed on the transfer trolley, the transfer trolley is moved to a separating area, the upper end of the driving rod 6 is aligned with the hole of the fuel basket center column 5, the interface 11 of the operating long rod 10 is inserted on the pin 12, and the operating long rod 10 is clamped with the pin 12 by rotating the operating long rod 10, the lower end of the driving rod 6 is inserted into the guide hub 7, the fuel basket 4 is lowered until the upper end of the driving rod 6 is in contact with the head of the grab head center rod 2, it is confirmed that the fuel basket 4 is in complete contact with the grab head center rod 2, the interface 11 of the operating long rod 10 is connected with the pin 12, and the operating long rod 10 is clamped with the pin 12 by rotating the pin 12, the operating long rod 10 is pressed downward, the driving rod 6 is driven to move upward, and the steel ball 3 slides downward, so that the grab head and the fuel basket 4 are separated.

[0031] A method for separating a grab head and a fuel basket center column, comprising the following steps.

[0032] 1. The fuel basket 4 is lifted from underwater to a shielding work station, and it is confirmed that the grab head and the fuel basket center column 5 are in a locked state.

[0033] 2. The separating tool for the grab head and the fuel basket center column is placed on the transfer trolley, the transfer trolley is moved to a separating area, is just above the fuel basket 4, and the upper end of the driving rod 6 is aligned with the fuel basket center column 5.

[0034] 3. The interface 11 of the operating long rod 10 is inserted on the pin 12, and the operating long rod 10 is clamped with the pin 12 by rotating the operating long rod 10, and the lower end of the driving rod 6 is inserted into the guide hub 7.

[0035] 4. The fuel basket 4 is lowered until the upper end of the driving rod 6 is in contact with the head of the grab head center rod 2.

[0036] 5. It is confirmed that the fuel basket 4 is in complete contact with the grab head center rod 2, the operating long rod 10 is pressed downward, the swing rod 8 moves upward, the driving rod 6 is driven to move upward, so that the grab head center rod 2 is moved upward, at this time, the steel ball 3 slides downward, and the fuel basket 4 is separated.

[0037] 6, repeat the down, up the long rod 10 3MM, until the gripper head and fuel basket 4 completely off, and then push the transfer trolley starter pin and start separator, the gripper head and fuel basket 4 completely separated; up the gripper head back to the shielding workstation inspection and processing;

[0038] 7, the processing is completed, lower the gripper head, reconnection will fuel basket 4 to the shielding workstation, transfer trolley separation zone in place;

[0039] 8, rotate the operating rod 10 to disconnect the operating rod 10 and the pin 12, store the separation tool parts.

[0040] The gripper head and fuel basket center column separation tool and method provided by the application is simple to operate, has strong practicability, and has a success rate of 100% through multiple test verifications, can realize separation of the gripper head and the fuel basket center column, ensures safe, efficient and orderly production of spent fuel dry storage, and provides technical support and reference for subsequent similar power station related projects.

[0041] The above-described embodiments only express several embodiments of the present application, and the description is more specific and detailed, but it cannot be understood as a limitation on the scope of the patent of the present application. It should be pointed out that, for ordinary skilled persons in the art, without departing from the concept of the present application, a number of modifications and improvements can be made, which all belong to the protection scope of the present application. Therefore, the protection scope of the patent of the present application should be subject to the appended claims.

Claims

1. A tool for separating a gripper head from a fuel basket center column, characterized in that: The utility model comprises a driving rod (6), a guide hub (7), a swing rod (8), a transfer trolley turntable (9), an operating long rod (10) and a bayonet (12); a guide hub (7) is provided in the middle of the transfer trolley turntable (9); a bayonet (12) is provided at the end of the transfer trolley turntable (9); one end of the swing rod (8) is connected to the lower end of the guide hub (7); the other end of the swing rod (8) is connected to one side of the bayonet (12); the operating long rod (10) is connected to the bayonet (12); and an interface (11) is provided at the bottom of the operating long rod (10), and the interface (11) is connected to the bayonet (12).

2. The tool for separating the gripper head from the center column of the fuel basket according to claim 1, characterized in that: The interface (11) is snap-connected to the bayonet pin (12).

3. The tool for separating the gripper head from the center column of the fuel basket according to claim 1, characterized in that: An operating handle is provided at the end of the operating long rod (10).

4. The tool for separating the gripper head from the center column of the fuel basket according to claim 1, characterized in that: The length of the operating long rod (10) is adjustable.

5. The tool for separating the gripper head from the center column of the fuel basket according to claim 1, characterized in that: The length of the driving rod (6) is adjustable.

6. A method for separating a gripper head from a fuel basket center column, characterized in that: Using the tool for separating the gripper head from the center column of the fuel basket according to any one of claims 1 to 5 comprises the following steps: 1) Lift the fuel basket (4) from underwater to the shielding workstation and confirm that the gripper head and the fuel basket center column (5) are locked; 2) Place the tool for separating the gripper head from the center column of the fuel basket (4) on a transfer trolley, move the transfer trolley to the separation area, and align the upper end of the drive rod (6) with the center column of the fuel basket (4); 3) Insert the interface (11) of the operating rod (10) onto the latch (12), and rotate the operating rod (10) to lock the operating rod (10) and the latch (12); insert the lower end of the driving rod (6) into the guide hub (7); 4) Lower the fuel basket (4) until the upper end of the drive rod (6) contacts the head of the center rod (2) of the gripper head; 5) Confirm that the fuel basket (4) is in full contact with the center rod (2) of the gripper head, press down the operating rod (10), the swing rod (8) moves upward, driving the driving rod (6) to move upward, thereby moving the center rod (2) of the gripper head upward, at which time the steel ball (3) slides down and separates from the fuel basket (4); 6) Repeatedly press down and lift the operating rod (10) 3mm until the gripper head is completely disengaged from the fuel basket (4), and then push the starting pin and the starting separator on the transfer trolley to completely separate the gripper head from the fuel basket (4); lift the gripper head back to the shielding workstation for inspection and processing; 7) After the processing is completed, the gripper head is lowered and reconnected to move the fuel basket (4) to the shielding workstation, and the transfer trolley separation area is in place; 8) Rotate the operating rod (10) to disengage the operating rod (10) from the latch (12) and store the separation tool components.

Images