RU2510086C2 - Loading method of dav-90 irradiated units, and device for its implementation - Google Patents

Abstract

FIELD: power industry.

SUBSTANCE: inventions refer to transportation and transshipment of highly-enriched irradiated dispersion fuel elements in an aluminium cover of DAV-90 type (hereinafter referred to as ODAV) to a transport packing container (TPC). A method involves transportation of ODAV units from an examination table to TPC, and loading of ODAV units into TPC. Loading of a cover with ODAV units is performed on the examination table; installation of the cover loaded with ODAV units into TPC is performed without using any hopper and a loading trolley. ODAV units are loaded on the examination table immediately into TPC cover under water layer by means of a manual manipulator. A grip includes a load-carrying rod with a mechanical grip of clip-on type. With that, the grip is equipped with a spring, a retaining ring and a pneumatic cylinder with a remote control unit. The proposed grip is opened in a forced manner at remote supply of excess pressure to the upper cavity of a pneumatic cylinder, which provides only controlled opening. In case there is no excess pressure in the upper cavity of the pneumatic cylinder, the spring automatically moves the ring that closes the grip and locks levers in a closed position.

EFFECT: excluding possible self-opening of a grip; improving reliable retention of load during transportation; increasing radiation safety of personnel at ODAV loading to TPC and reducing loading time.

2 cl, 4 dwg

Description

The invention relates to nuclear technology, in particular, to the management of spent nuclear fuel, and more specifically to the transportation and transfer of irradiated highly dispersed fuel elements in an aluminum cladding of the DAV-90 type (hereinafter referred to as “ODA” blocks) to a transport packaging container (TUK).

There is a known method for loading ODA units (see project "0304" Inv. No. OS-03237 developed by JSC East European Head Research and Design Institute for Energy Technologies), the technological solutions of which (0304-TX) include the assembly of buckets available at the enterprise in batches of 180 ODAV blocks on a parsing table under a layer of water, transporting buckets under a layer of water and removing them from water to a loading bunker located above the water, where ODOV blocks are poured through a telescopic chute of a loading trolley into a cover installed in a transport packaging package (TUK), while the cover is not removed from the inner cavity of the container.

The disadvantages of this method include the fact that the boot cover TUK is made by pouring blocks ODA in the air.

The specified disadvantage of the known method of loading may lead to undesirable consequences. When pouring blocks, scattering of ODA blocks is not ruled out, which significantly reduces the radiation safety of personnel. The pouring of the ODAV blocks is accompanied by impacts on the steel parts of the hopper, which is likely to lead to damage to the shells of the ODAV. Damage to the sheath leads to radiation contamination of the premises and equipment of not only the sender of the ODA, but also the receiver.

Another disadvantage of this method is the fact that to load one TUK requires pouring two buckets with blocks ODAV, which increases the number of transport operations.

The known method is carried out using known devices, namely:

1) The complex of existing technical equipment of the reactor plant, providing for the completion of ODAW ladles, transportation of buckets to the loading area, lifting of ladles and pouring ODAW through the hopper and through the telescopic estrus of the loading trolley to the TUK.

2) Electro-hydraulic machine Brokk-50 and a manipulator for remote collection of possible emergency spills of ODA units.

3) A well-known design capture intended for removing the cover from the TUK, transporting the cover to the emergency discharge shaft and vice versa, installing the cover in the TUK.

The principle of operation of the known capture is adopted from the design of automatic capture of the Melamed system - it is a load gripping device with an automatic device for sequential capture and release of cargo equipped with a transport pin. The known device contains paws for engagement with the protrusions of the transport pin, the sprocket Melamed, the outer and inner bodies and the central rod.

The work of the known capture is characterized by the following successive provisions:

Position 1. The grip is ready for use: - the outer casing is in the lowest position, the tabs are open, the central rod and the movable casing are in the highest upper positions, the sprocket is oriented at an angle of ~ 10 ... 15 °, the tooth of the sprocket is in the groove of the movable casing. In this position, the device is transported without load.

Regulation 2. Cargo engagement. The grip is lowered onto the transport pin, the cone guides the pin to the stop with the stop, the outer casing stops, and the inner casing and the central stem continue to move down due to their own weight. The central rod closes the grip tabs and becomes on the stop, the movable body continues to move down and with a special finger turns the sprocket in such a way that the second sprocket tooth enters the slot of the body, and the sprocket itself is oriented horizontally (~ 0 °).

When lifting the load, the inner movable housing starts to move up to the stop in the flange of the outer housing and the special finger leaves the sprocket, while the lower edge of the slot of the movable housing rotates the sprocket so that it blocks the possibility of the central rod to move up, i.e. blocks the ability to open the legs. Capture is closed, ready for transportation of goods;

Regulation 3. Transportation of goods. The load is distributed: paws, power axis, outer casing, flange of the movable inner casing, lifting mechanism.

Position 4. The load is lowered into place, the transport pin is stationary. The release of cargo is as follows. The outer casing lowers, abuts the pin and stops. The inner movable housing continues to move downward, a special finger rotates the sprocket in such a way that the sprocket tooth enters the slot of the movable housing, and it rotates the sprocket by ~ 45 ° (orients the sprocket almost horizontally).

After turning the sprocket, it will be possible to further lower the outer casing, while the central stem remains in place, and the outer and inner casings are lowered. When the outer casing is moved down, the grip tabs open, the load is released. The cargo is released, the capture is in position 1.

The disadvantages of the known capture include the fact that the automatic opening of the capture in case of accidental contact of the load with the surface will lead to the fall of the cover and placer ODA. There is no mechanism to block automatic opening. A grip of 1100 mm in length is placed directly on the hook of the load-lifting mechanism, this suspension method makes it difficult to direct the grip to the transport pin from a remote protected control panel (especially if the load is under water or in a mine).

These shortcomings of the known capture reduce the radiation safety of personnel when used with radiation-hazardous cargo ODA.

The proposed inventions are aimed at achieving a technical result, which consists in increasing the radiation safety of personnel when loading TAC in TUK by pouring TADA in water and reducing transport operations when loading TUK.

To obtain the indicated technical result in the proposed method, which includes transporting the ODA units from the parsing table to the TUK, loading the ODA units into the TUK, the empty cover is removed from the TUK and transported to the parsing table, the cover is loaded with the irradiated DAV-90 blocks under a layer of water with a hand manipulator, transported under water and set the loaded cover in the TUK without spilling blocks.

Removing the empty cover from the TUK, transporting it to the parsing table allows full loading of the cover with ODA units and, thereby, reducing the number of transport operations.

Loading a cover with irradiated DAV-90 blocks under a layer of water with a manual manipulator, transporting a loaded cover and installing it in a TUK can eliminate the spillage of ODAW blocks in air, reduce the likelihood of scattering of ODAW blocks and damage to their shells, and thereby increase the radiation safety of personnel.

To obtain the specified technical result in the proposed grip, including a supporting rod with a mechanical grip of a tick-type type, a spring, a retaining ring and a pneumatic cylinder with a remote control unit, the spring automatically moves the retaining ring, which closes the grip and locks the levers in the closed position in the absence of excess pressure in the upper cavity of the pneumatic cylinder.

The automatic spring movement of the locking ring, which closes the grip and locks the levers in the closed position in the absence of excess pressure in the upper cavity of the pneumatic cylinder, eliminates the possibility of self-opening of the gripper, ensures reliable retention of the loaded cover during transportation, and thereby increases the radiation safety of personnel when loading ODA into the TUK.

The invention is illustrated by the drawings shown in FIG. fourteen:

in FIG. 1 - transport-technological scheme of loading TUK;

in FIG. 2 - capture with remote control;

in FIG. 3 - capture in the open position;

in FIG. 4 - capture in the closed position.

The proposed method of loading is carried out using

the proposed capture in the following sequence (see Fig. 1):

- dismantle the outer cover of the TUK;

- remove the inner cover of the TUK;

- remove the cover from the TUK;

- install using the proposed capture empty cover in the bucket;

- move the bucket with an empty cover to the parsing table;

- remove the empty cover from the bucket on the parsing table;

- load the ODAV blocks into the case;

- install the loaded cover into the bucket;

- move the loaded case to the TUK;

- remove the loaded cover from the bucket;

- install the loaded cover in the TUK;

- install the inner cover of the TUK;

- Mount the outer cover of the TUK.

The proposed method does not use a hopper, special crane and loading trolley.

The proposed grip (see Fig. 2) consists of a support rod 1, a suspension unit on a crane 2, a power axis 3, on which levers 4 are suspended, which in the grooves of the cylindrical body 5 can be rotated on the axles 6. The spring gripping mechanism contains a thrust nut 7 , spring 8, housing of the pneumatic cylinder 9, pipe 10, ring 11. The capture pneumatic cylinder contains a housing 9, a piston 12 and a rod 13. The piston of the pneumatic cylinder 12 is mounted on the rod 13, both ends of which protrude beyond the housing at any piston position, the rod 13 is of tubular construction worn on support bar 1 and secured and her.

The proposed capture works as follows.

The grip is always closed, the load from the load from the levers 4 through the power axis 3 along the support rod 1 is transferred to the suspension unit on the crane 2. The translation of the levers from the closed position to the open and back is provided by moving up and down the ring 11, connected through the pipe 10 to the body of the pneumatic cylinder 9 .

Closing the grip (see Fig. 4): under the action of the spring 8, the ring 11 moves down along the conical surfaces of the levers 4, turning them around the axes 6. In the closed position, the levers are fixed by a ring 10, which prevents their spontaneous opening. In the closed position, the contact plane of the levers and the transport pin (13) are parallel.

Opening of the gripper (see Fig. 3): when the ring 11 is moved up, the protrusions on the levers 4 engage with a shoulder on the ring 11 and the levers rotate around the axles 6, releasing the transport pin 13. To open the gripper, it is necessary to exert a force exceeding the ring 11 spring force and move it upwards by 40 ... 50 mm. The necessary effort is created by a pneumatic cylinder, into the upper cavity of which compressed air 5 kgf / cm ² is supplied. When air is supplied (see Fig. 2), the piston of the cylinder 12 remains stationary (since the tubular rod is fixed on the supporting rod), and the body of the pneumatic cylinder 9 starts to move upward, overcoming the force of the spring 8. Since the body of the pneumatic cylinder is rigidly connected by the pipe 10 to the ring 11 then the ring 11 will move upward, opening the levers 3.

To close the mechanism, it is necessary to relieve excess air pressure from the upper cavity of the pneumatic cylinder, then under the action of the spring 8, the housing 9 and the ring 11 will return to the lower position, closing and fixing the levers.

The capture sample was manufactured and tested at the facility.

Claims (2)

1. A method for handling spent nuclear fuel (for transporting and overloading irradiated fuel elements dispersed in an aluminum sheath of highly enriched DAV-90 type), including transporting the DAV-90 blocks from the parsing table to the transport packaging container (TUK), loading the DAV-90 blocks into TUK, characterized in that the empty cover is removed from the TUK and transported to the parsing table, the cover is loaded with irradiated DAV-90 blocks under a layer of water with a manual manipulator, transported under water and a loaded cover is installed in TUK. 2. Remote-controlled gripper, comprising a support rod with a mechanical clamp-type gripper, a spring, a retaining ring and a pneumatic cylinder with a remote control unit, characterized in that in the absence of excessive pressure in the upper cavity of the pneumatic cylinder, the spring automatically moves the ring, which closes the gripper and locks the levers in the closed position.

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