阅读说明：本技术 一种压水堆堆腔辐射漏束屏蔽装置 (Pressurized water reactor cavity radiation beam leakage shielding device ) 是由 肖锋 唐松乾 李兰 谭怡 景福庭 应栋川 邓理邻 吕焕文 刘嘉嘉 于 2019-11-05 设计创作，主要内容包括：本发明公开了一种压水堆堆腔辐射漏束屏蔽装置,包括呈堆腔底部构架,还包括辐射屏蔽组件,所述辐射屏蔽组件包括第三包壳,第三包壳的管状空隙内还填充有第二屏蔽填充层；所述堆腔底部构架包括混凝土部分及填充层部分；所述混凝土部分包括呈圆环状的第一包壳,第一包壳的管状空隙内还填充有混凝土填充层；所述填充层部分包括呈圆环状的第二包壳,第二包壳的管状空隙内还填充有第一屏蔽填充层；所述第二包壳的外侧与第一包壳的内侧相接；第二屏蔽填充层、第一屏蔽填充层、混凝土填充层三者均呈圆环状；第二包壳的内径小于第三包壳的内径。本屏蔽装置的结构设计可有效避免混凝土温度超标,同时具有良好的辐射漏束屏蔽效果。(The invention discloses a pressurized water reactor cavity radiation beam leakage shielding device, which comprises a reactor cavity bottom framework and a radiation shielding assembly, wherein the radiation shielding assembly comprises a third cladding, and a second shielding filling layer is filled in a tubular gap of the third cladding; the pile cavity bottom framework comprises a concrete part and a filling layer part; the concrete part comprises a first annular cladding, and a concrete filling layer is filled in a tubular gap of the first cladding; the filling layer part comprises a second annular cladding, and a first shielding filling layer is filled in a tubular gap of the second cladding; the outer side of the second cladding is connected with the inner side of the first cladding; the second shielding filling layer, the first shielding filling layer and the concrete filling layer are all in a circular ring shape; the second cladding has an inner diameter less than the inner diameter of the third cladding. The shielding device has the advantages that the structural design can effectively avoid the concrete temperature exceeding, and meanwhile, the shielding device has a good radiation beam leakage shielding effect.)

1. A pressurized water reactor cavity radiation beam leakage shielding device comprises a circular reactor cavity bottom framework and is characterized by further comprising a radiation shielding assembly, wherein the radiation shielding assembly comprises a third cladding (10), the third cladding (10) is circular, the third cladding (10) is of a hollow tubular structure, and a second shielding filling layer (11) is filled in a tubular gap of the third cladding (10);

the pile cavity bottom framework comprises a concrete part and a filling layer part;

the concrete part comprises a first annular cladding (3), the first cladding (3) is of a hollow tubular structure, and a concrete filling layer (2) is filled in a tubular gap of the first cladding (3);

the filling layer part comprises a second annular cladding (5), the second cladding (5) is of a hollow tubular structure, and a first shielding filling layer (6) is filled in a tubular gap of the second cladding (5);

the outer side of the second cladding (5) is connected with the inner side of the first cladding (3);

the second shielding filling layer (11), the first shielding filling layer (6) and the concrete filling layer (2) are all in a ring shape;

the inner diameter of the second wrapper (5) is smaller than the inner diameter of the third wrapper (10).

2. The pressurized water reactor cavity radiation beam leakage shielding device according to claim 1, characterized in that the inner side wall surface of the second cladding (5) is a conical surface, the outer side wall surface of the third cladding (10) is a conical surface, and the inner side wall surface of the second cladding (5) and the outer side wall surface of the third cladding (10) have the same inclination angle.

3. The pressurized water reactor cavity radiation beam leakage shielding device according to claim 1, characterized in that a second insulating layer (9) is further arranged in the tubular gap of the third cladding (10), and the second insulating layer (9) is attached to the wall surface close to the inner side of the third cladding (10).

4. The pressurized water reactor cavity radiation beam leakage shielding device according to claim 1, further comprising a first thermal insulation layer (4) arranged between the concrete part and the filling layer part, wherein the first thermal insulation layer (4) is used for reducing heat transfer between the concrete part and the filling layer part.

5. The pressurized water reactor cavity radiation leakage beam shielding device according to claim 1, characterized in that the first cladding (3), the second cladding (5) and the third cladding (10) are all made of stainless steel material.

6. The pressurized water reactor cavity radiation beam leakage shielding device according to claim 1, wherein the second shielding and filling layer (11) and the first shielding and filling layer (6) are made of any one or more of the following materials: boron carbide, boron steel, high-temperature-resistant boron-containing resin and high-temperature-resistant boron-containing plastic.

7. Pressurized water reactor cavity radiation beam leakage shielding according to any of claims 1 to 6, characterized in that the difference between the inner diameter of the second cladding (5) and the inner diameter of the third cladding (10) is Amm, the value of A is between 20 and 50, the value of Bmm of the length inside the second cladding (5), the value of Cmm of the length inside the third cladding (10), and the values of B and C are between 20 and 50.

Technical Field

The invention relates to the technical field of nuclear reactor structural design, in particular to a pressurized water reactor cavity radiation beam leakage shielding device.

Background

An annular gap is reserved between a reactor body and reactor cavity concrete of a nuclear power plant, the annular gap provides space for arrangement and installation of equipment such as a reactor heat-insulating layer and a support, a flow channel is provided for cooling and ventilation of an annular cavity, a channel for outward transport of neutrons leaked from a reactor core is formed due to the annular gap, the radiation level from a reactor top structure of the reactor to an operation platform of a reactor plant is directly increased, and the activation level of a reactor top structure material and the radiation dose of the operation platform are increased during operation. Nuclear power plants at home and abroad commonly use a structure of a reactor cavity bottom framework to shield annular gaps. Due to the existence of the heat-insulating layer of the reactor pressure vessel, the framework at the bottom of the reactor cavity is not enough to effectively shield radiation leakage beams. If the gap between the bottom frame of the reactor cavity and the pressure vessel is further compressed, the thermal insulation layer is damaged, and the heat conduction of the pressure vessel to the bottom frame of the reactor cavity is increased, so that the temperature of the bottom frame of the reactor cavity and the primary shielding concrete connected with the bottom frame of the reactor cavity is directly increased, and the temperature of the primary shielding concrete may exceed the tolerance temperature of the material.

The traditional pile cavity bottom framework structure uses a stainless steel groove, and boron-containing heavy concrete is poured in the groove. The whole structure is fixed on the inner surface of the pile cavity concrete through a steel cantilever. The main disadvantages of this structure are: 1) a large gap is reserved between the pile cavity bottom framework and the pressure container, which is not beneficial to the pile cavity bottom framework to play a shielding role, 2) the material used by the pile cavity bottom framework is low in temperature tolerance, and the temperature of the shielding material exceeds the standard when the gap is continuously reduced.

Disclosure of Invention

Aiming at the problem of contradiction between shielding effect and temperature tolerance caused by the fact that the structural design of the bottom framework of the reactor cavity in the prior art adopts the boron-containing heavy concrete, the invention provides the pressurized water reactor cavity radiation beam leakage shielding device.

In order to solve the problems, the invention provides a pressurized water reactor cavity radiation beam leakage shielding device which solves the problems through the following technical key points: a pressurized water reactor cavity radiation beam leakage shielding device comprises a circular reactor cavity bottom framework and a radiation shielding assembly, wherein the radiation shielding assembly comprises a third cladding, the third cladding is circular, the third cladding is of a hollow tubular structure, and a second shielding filling layer is filled in a tubular gap of the third cladding;

the pile cavity bottom framework comprises a concrete part and a filling layer part;

the concrete part comprises a first annular cladding, the first cladding is of a hollow tubular structure, and a concrete filling layer is filled in a tubular gap of the first cladding;

the filling layer part comprises a second annular cladding, the second cladding is of a hollow tubular structure, and a first shielding filling layer is filled in a tubular gap of the second cladding;

the outer side of the second cladding is connected with the inner side of the first cladding;

the second shielding filling layer, the first shielding filling layer and the concrete filling layer are all in a circular ring shape;

the second cladding has an inner diameter less than the inner diameter of the third cladding.

The pressurized water reactor cavity radiation beam leakage shielding device provided by the scheme is used for being installed in an annular gap between reactor cavity concrete and a pressure container. The third cladding, the second cladding and the first cladding are all circular in shape, when the pressure vessel is used, the third cladding, the second cladding and the first cladding are all around the circumferential direction of the pressure vessel, meanwhile, the inner diameter of the second cladding is smaller than that of the third cladding, and the outer side of the second cladding is connected with the inner side of the first cladding, so that the pressure vessel is divided into the following parts from inside to outside along the radial direction of the pressure vessel: a third enclosure, a second enclosure, and a first enclosure.

When in use, the radiation shielding component is embedded in the heat-insulating layer of the pressure vessel, the bottom framework of the reactor cavity is used for being fixed on the concrete of the reactor cavity, as the technical personnel in the field are provided with the shielding function, the radiation shielding component and the bottom framework of the reactor cavity are preferably arranged to be positioned at the same point on the axis of the pressure vessel, and the inner diameter of the second cladding is smaller than that of the third cladding, so that after the device is assembled, a gap between the third cladding and the second cladding is formed between the radiation shielding component and the bottom framework of the reactor cavity, namely the device comprises two parts, wherein one part is embedded in the heat-insulating layer of the pressure vessel, and the other part is fixed on the concrete of the reactor cavity, so that the radiation shielding component embedded in the heat-insulating layer of the pressure vessel can be used for shielding radiation beam leakage in the area where the heat-insulating layer of the pressure vessel, the pile cavity bottom framework fixed on the pile cavity concrete can be used for shielding radiation beam leakage of a gap between the pressure vessel heat-insulating layer and the pile cavity concrete. Compared with the pressure vessel heat-insulating layer in the prior art which hardly has any radiation beam leakage shielding capacity, the radiation shielding component can effectively strengthen the radiation beam leakage shielding effect. Meanwhile, as the radiation shielding assembly is an embedded shielding filling layer, in the prior art, the shielding filling layer can be made of materials such as boron carbide, boron steel, high-temperature-resistant boron-containing resin, high-temperature-resistant boron-containing plastic, high-temperature-resistant boron-containing concrete and the like, and under the condition that the density of the shielding filling layer is smaller than that of the concrete, the shielding filling layer keeps good shielding capacity and high-temperature-resistant capacity, and meanwhile, the heat-insulating layer of the pressure container is small in bearing load, and good shape keeping capacity is guaranteed so as to be beneficial to the heat-insulating.

The radiation shielding assembly comprises a first shielding filling layer and a concrete filling layer, wherein the first shielding filling layer is wrapped by a second cladding, and the concrete filling layer is wrapped by the first cladding from inside to outside along the radial direction of the pressure container.

In this scheme simultaneously, set up to this device for being divided into two parts's split type design, wherein on the partly is fixed in the heap chamber concrete including the concrete filling layer, another part is fixed in on the pressure vessel heat preservation, and has the clearance between the two parts, thus, partly can not lead to the fact the influence to the part that is fixed in on the pressure vessel heat preservation including the concrete filling layer, the expansion joint can be regarded as to the clearance more than simultaneously, in order at this device or the part expend with heat and contract with cold in-process that links to each other with this device, avoid two parts interact and influence this device or the part that links to each other with this device, especially can effectively avoid expend with heat and contract with cold in-process pressure vessel heat preservation's heat preservation ability or structural style to suffer destruction.

In conclusion, the scheme provides the shielding device which can avoid the exceeding of the temperature of the environment where the concrete with the shielding effect is located and can play the ideal shielding effect.

The further technical scheme is as follows:

as a specific arrangement form of the second cladding and the third cladding, an inner side wall surface of the second cladding is a conical surface, an outer side wall surface of the third cladding is a conical surface, and the inner side wall surface of the second cladding and the outer side wall surface of the third cladding have the same inclination angle. By adopting the scheme, after the second cladding and the third cladding are coaxially mounted, the uniform gap width between the inner side of the second cladding and the outer side of the third cladding at any two points along the axial direction of the pressure container can be realized. Meanwhile, an included angle is formed between the conical surface and the axis corresponding to the second cladding or the third cladding, so that the gap has a specific inclination angle from bottom to top or from top to bottom, and a labyrinth sealing structure can be formed aiming at the radiation leakage beam shielding.

In order to reduce the heat transfer quantity from the pressure container to the shielding device, optimize the temperature environment of the device and reduce the heat loss of the pressure container, a second heat-insulating layer is further arranged in the tubular gap of the third cladding and is attached to the wall surface close to the inner side of the third cladding. By adopting the scheme, the second heat-insulating layer is arranged between the third cladding and the second shielding filling layer and is used for insulating heat between the third cladding and the second shielding filling layer, so that local high temperature on one side of the second shielding filling layer close to the pressure container can be effectively avoided.

In order to reduce the heat transfer on the shielding device, lower the working temperature of the concrete filling layer and reduce the heat loss of the pressure vessel, the shielding device further comprises a first heat preservation layer arranged between the concrete part and the filling layer part, and the first heat preservation layer is used for reducing the heat transfer between the concrete part and the filling layer part.

As a specific implementation mode of the enclosure, the first enclosure, the second enclosure and the third enclosure are all made of stainless steel materials.

As a specific implementation manner of the shielding filling layer, the second shielding filling layer and the first shielding filling layer are made of any one or more of the following materials: boron carbide, boron steel, high-temperature-resistant boron-containing resin and high-temperature-resistant boron-containing plastic.

As a specific implementation mode for limiting the radiation leakage caused by the gap, the difference between the inner diameter of the second cladding and the inner diameter of the third cladding is Amm, the value of A is between 20 and 50, the value of Bmm of the inner length of the second cladding, the value of Cmm of the inner length of the third cladding, and the values of B and C are between 20 and 50. Further, aiming at the scheme that the outer wall surface of the third cladding shell and the inner wall surface of the second cladding shell are conical surfaces, the included angle between the outer wall surface and the inner wall surface and the axis of the corresponding cladding is a, preferably, a is set to be less than or equal to 15 degrees, so that the structural strength of the corresponding cladding is not influenced by the corresponding conical surface.

The invention has the following beneficial effects:

when the device is used, the radiation shielding component is embedded in the heat-insulating layer of the pressure container, the bottom framework of the reactor cavity is used for being fixed on the concrete of the reactor cavity, as a person skilled in the art, due to the shielding effect of the device, the radiation shielding component and the bottom framework of the reactor cavity are preferably arranged at the same point on the axis of the pressure container, and the inner diameter of the second cladding is smaller than that of the third cladding, so that after the device is assembled, a gap between the third cladding and the second cladding is formed between the radiation shielding component and the bottom framework of the reactor cavity, namely the device comprises two parts, wherein one part is embedded in the heat-insulating layer of the pressure container, and the other part is fixed on the concrete of the reactor cavity, so that the radiation shielding component embedded in the heat-insulating layer of the pressure container can be used for shielding radiation beam leakage in the area where the heat-insulating layer of the pressure, the pile cavity bottom framework fixed on the pile cavity concrete can be used for shielding radiation beam leakage of a gap between the pressure vessel heat-insulating layer and the pile cavity concrete. Compared with the pressure vessel heat-insulating layer in the prior art which hardly has any radiation beam leakage shielding capacity, the radiation shielding component can effectively strengthen the radiation beam leakage shielding effect. Meanwhile, as the radiation shielding assembly is an embedded shielding filling layer, in the prior art, the shielding filling layer can be made of materials such as boron carbide, boron steel, high-temperature-resistant boron-containing resin, high-temperature-resistant boron-containing plastic and the like, and under the condition that the density of the shielding filling layer is smaller than that of concrete, the shielding filling layer keeps good shielding capacity and high-temperature-resistant capacity, and meanwhile, the pressure container heat-insulating layer is small in bearing capacity and beneficial to ensuring good shape keeping capacity so as to be beneficial to the heat-insulating effect.

The radiation shielding assembly comprises a first shielding filling layer and a concrete filling layer, wherein the first shielding filling layer is wrapped by a second cladding, and the concrete filling layer is wrapped by the first cladding from inside to outside along the radial direction of the pressure container.

In this scheme simultaneously, set up to this device for being divided into two parts's split type design, wherein on the partly is fixed in the heap chamber concrete including the concrete filling layer, another part is fixed in on the pressure vessel heat preservation, and has the clearance between the two parts, thus, partly can not lead to the fact the influence to the part that is fixed in on the pressure vessel heat preservation including the concrete filling layer, the expansion joint can be regarded as to the clearance more than simultaneously, in order at this device or the part expend with heat and contract with cold in-process that links to each other with this device, avoid two parts interact and influence this device or the part that links to each other with this device, especially can effectively avoid expend with heat and contract with cold in-process pressure vessel heat preservation's heat preservation ability or structural style to suffer destruction.

In conclusion, the scheme provides the shielding device which can avoid the exceeding of the temperature of the environment where the concrete with the shielding effect is located and can play the ideal shielding effect.

Drawings

Fig. 1 is a schematic structural view of an embodiment of a pressurized water reactor cavity radiation leakage beam shielding device according to the present invention, and the schematic structural view is a partial sectional view.

The labels in the figure are respectively: 1. pile chamber concrete, 2, concrete filling layer, 3, first cladding, 4, first heat preservation, 5, second cladding, 6, first shielding filling layer, 7, clearance, 8, pressure vessel heat preservation, 9, second heat preservation, 10, third cladding, 11, second shielding filling layer, 12, annular gap.

Detailed Description

The present invention will be described in further detail with reference to the following examples, but the present invention is not limited to the following examples: