RU103657U1 - REACTOR PIPE UNIT INSTALLATION AND DISASSEMBLY DEVICE - Google Patents

Abstract

1. A device for assembling and dismantling a block of reactor pipes containing a container with a gate valve located in the lower part of the container, a plate with gripping devices, characterized in that the device is equipped with a support-guide shell equipped with a lower thrust flange, and the gate valve is made of at least two parts. ! 2. The device according to claim 1, characterized in that in the upper part of the container there are retractable stops. ! 3. The device according to claim 1, characterized in that the plate is equipped with roller stops, and keys are installed on the inner surfaces of the container and the supporting-guide shell.

Description

The utility model relates to the field of nuclear engineering and can be used as a special device for assembling and disassembling the reactor tube block during fuel reloading at WWER-type reactors, in particular during fuel reloading at floating nuclear power plants and transport installations.

A distinctive feature of VVER-type reactors is the presence of an internal reactor block of the upper structures (reactor pipe block) installed in the reactor vessel above the core. To perform core reloading operations, it is necessary to dismantle the upper structure block, and upon completion of core reloading operations, reassemble it into the reactor vessel. The handling equipment for the dismantling and installation operations of the block of the upper structures must have a large carrying capacity and provide protection for the personnel from radioactive radiation. To accommodate handling equipment, space is required in the reactor room. In the case of stationary nuclear installations, this problem does not cause great difficulties. The design features of the transport units do not allow for the arbitrarily large dimensions of the reactor hall and, accordingly, the lifting equipment has limitations on the maximum lifting capacity.

The invention “Storage mechanisms for overloading reactor equipment” is known, which describes the operation of mechanisms for assembling and disassembling reactor structures and installing them for temporary storage in a storage room in a reactor hall. This technical solution is intended for use in stationary nuclear power plants with WWER reactors. To dismantle the internal reactor structures, the invention uses a machine moving along rails in the reactor hall. The transfer of the reactor structures to the storage place is carried out under a layer of water. (US Patent US No. 4859404 from 08/22/89)

The disadvantages of this design include:

Large overall dimensions of the car;

There is no design to protect maintenance personnel from radiation exposure;

Large volumes of the reactor room, due to the size of the machine moving on rails;

The presence of large volumes of water, which serves as radiation protection.

A known machine for overloading the lid of the reactor and the upper internal structures described in the invention, "Loading and unloading of the reactor core". The machine consists of a frame equipped with rollers, which are adapted to move along rails that are fixed on the floor and extend from the storage niche to the area above the reactor opening. The machine includes independent lifting means, consisting of two telescopic jacks, each of which is able to lift the pressure housing cover. These jacks are provided at the lower ends with means for attaching to the housing cover. When the cover is stored in a niche, the jacks remain attached to it. For lifting the upper internal structure, the machine includes a winch system. (US Patent US No. 4056435 dated 07/07/1975)

The disadvantages of this design include:

Large overall dimensions of the car;

To place and move the machine on rails, a large space in the reactor hall is necessary.

The complexity of the design associated with the use of several loading mechanisms;

Filling the overload path with water complicates the design of the system, makes it difficult to control the operation of mechanisms;

The closest technical solution to the solution according to the proposed utility model is the invention "Transport-reloading container for reloading the core of a nuclear reactor", which describes the device container designed to reload the core of the reactor completely. The container consists of a hermetically sealed enclosure with integrated devices for lifting the core from the reactor, cooling and ventilation systems. At the bottom of the container there are slide gate valves with actuators and damping devices. Moving the container is carried out using a crane. The design of the container provides protection of personnel from radioactive radiation. (Russian Patent RU No. 2157008 dated January 5, 1999)

The disadvantages of this design include:

The complexity of the device, due to the presence of sealing systems and cooling, necessary when overloading the core, characterized by large residual heat and high radioactivity;

The container is not unified, it is intended only for overloading the core and is not intended for mounting and dismounting the block of upper structures;

The technical task of the proposed utility model is the creation of a device for assembling and disassembling a reactor pipe block with minimum weight and size characteristics, allowing the use of existing lifting equipment used for overloading nuclear reactors in transport installations.

The problem is solved in that the proposed design of a device for assembling and disassembling a reactor tube block is made of two components: a lower shell and a guide shell installed in the upper part of the reactor vessel and an upper container directly for transporting the reactor tube tube reactor mounted on the flange reference guide shell. The container at the bottom is equipped with a slide gate valve consisting of at least two parts. Inside the container there is a plate with grippers. To center the plate inside the device, guide rollers are installed on the plate, and the container and the supporting guide shell are equipped with guide keys. Additionally, the side walls of the container, the plate and the slide gate valve perform the function of biological protection and provide radiation protection for maintenance personnel during installation and dismantling of the reactor pipe block.

The essence of the utility model is illustrated by drawings, where:

Figure 1 schematically shows a longitudinal section of a reactor vessel with an installed device for mounting and dismounting the reactor pipe block.

Figure 2 schematically shows a container with an installed inside the reactor pipe block.

Block 9 of the reactor tubes is located in the upper part of the reactor vessel 10 above the core. To overload the fuel assemblies of the active zone, it is necessary to dismantle the pipe block 9 from the body 10, and after the overload, install the pipe block 9 back into the body 10.

The structure of the installation-dismantling of the pipe block 9 includes:

a container 1 with a slide gate valve 2 and pull-out stops 3, a plate 4 with gripping devices 5, a supporting-guide shell 6 with a stop collar 7. The slide gate valve 2 is made of at least two parts to reduce the overall dimensions of the device. The roller stops 11 are mounted on the plate 4 in its upper part. The roller stops 11 are used to center the plate 4 and move along the keys 12 mounted on the inner walls of the bearing-guide shell 6 and the container 1. For installing the bearing-guide shell 6 on the upper flange of the housing 10 of the reactor is installed technological support 8.

The operation of the device is as follows:

The mounting and dismounting device for the reactor tube block is installed on the technological support 8, which is installed on the reactor vessel 10 after removing the reactor cover (not shown in the drawing), before the fuel assemblies are reloaded. The first is installed supporting the guide shell 6, leaning on the technological support 8 with the lower flange. The container 1 is installed on the upper flange of the supporting guide shell 6. Centering during movement of the plate 4 is carried out by moving the roller stops 11 mounted on the plate 4 along the dowels 12, mounted on the container 1 and the supporting-guide shell 6. The unit 9 of the reactor pipes is connected to the plate 4 with gripping devices 5. The plate 4 with the reactor pipe block 9 connected to it rises to the upper position and is fixed by the retractable stops 3. The slide gate valve is closed 2. The container 1 with the reactor pipe block 9 is moved to the temporary storage place (not shown in the drawing) . The bearing-guide shell 6 is removed and transferred to the place of temporary storage (not shown in the drawing). The installation of the block 9 of the reactor pipes in the reactor 10 is carried out in the reverse order after completion of operations associated with the overload of fuel assemblies.

The application of the proposed utility model for the installation and dismantling of the reactor pipe block allows the dismantling and installation of the reactor tube block during overloading of the reactor core in crowded conditions in transport facilities using existing lifting equipment.

In addition, the proposed device provides protection of personnel from radiation during operations related to the installation and dismantling of the reactor pipe block.

Claims (3)

1. A device for assembling and disassembling a block of reactor pipes, comprising a container with a slide gate valve located in the lower part of the container, a plate with gripping devices, characterized in that the device is equipped with a support-guide shell equipped with a lower stop flange, and the slide gate valve is made of at least two parts. 2. The device according to claim 1, characterized in that in the upper part of the container mounted retractable stops. 3. The device according to claim 1, characterized in that the plate is equipped with roller stops, and dowels are installed on the inner surfaces of the container and the supporting guide shell.