阅读说明：本技术 核燃料棒末端距离调节装置 (Nuclear fuel rod end distance adjusting device ) 是由 孙岁翼 李齐远 朴成俊 柳斗贤 于 2018-04-05 设计创作，主要内容包括：本发明涉及一种核燃料棒末端距离调节装置,更具体地,涉及一种能够通过将旋转运动转换为直线运动的装入动力机构而更细微地调节装入棒的移动长度,防止装入动力机构的旋转运动传递至装入棒,从而能够稳定地调节核燃料棒的末端距离的核燃料棒末端距离调节装置。提供一种核燃料棒末端距离调节装置,包括：装入棒,其包括核燃料棒钳,并进行前后方向的直线移动；中空的壳体；装入动力机构,其设于所述壳体的内侧,将旋转运动转换为直线运动并沿着所述壳体的长度方向移动；连接器,其连接于所述装入动力机构与所述装入棒之间；防旋转件,其设于所述装入动力机构与所述连接器之间,与所述装入动力机构的直线运动连动而沿所述壳体的长度方向移动,用于防止所述装入动力机构的旋转力传递至所述连接器。(The present invention relates to a nuclear fuel rod distal end distance adjusting apparatus, and more particularly, to a nuclear fuel rod distal end distance adjusting apparatus capable of preventing a rotational motion of a loading power mechanism from being transmitted to a loading rod by finely adjusting a moving length of the loading rod through the loading power mechanism converting the rotational motion into a linear motion, thereby stably adjusting a distal end distance of a nuclear fuel rod. There is provided a nuclear fuel rod tip distance adjusting device including: a loading rod including a nuclear fuel rod clamp and linearly moving in a front-rear direction; a hollow housing; a loading power mechanism which is arranged at the inner side of the shell, converts the rotary motion into linear motion and moves along the length direction of the shell; the connector is connected between the loading power mechanism and the loading rod; and a rotation preventing member provided between the loading power mechanism and the connector, moving in a length direction of the housing in linkage with a linear motion of the loading power mechanism, and preventing a rotational force of the loading power mechanism from being transmitted to the connector.)

1. A nuclear fuel rod tip distance adjustment device comprising:

a loading rod including a nuclear fuel rod clamp and linearly moving in a front-rear direction;

a hollow housing;

a loading power mechanism which is arranged at the inner side of the shell, converts the rotary motion into linear motion and moves along the length direction of the shell;

the connector is connected between the loading power mechanism and the loading rod;

and a rotation preventing member provided between the loading power mechanism and the connector, moving in a length direction of the housing in linkage with a linear motion of the loading power mechanism, and preventing a rotational force of the loading power mechanism from being transmitted to the connector.

2. The nuclear fuel rod tip distance adjustment device of claim 1, wherein,

the loading power mechanism is composed of a ball screw, a rotation space for the idle rotation of a bolt part of the ball screw is formed at one end part of the anti-rotation piece,

the connector is fixed to the other end of the rotation preventing member.

3. The nuclear fuel rod tip distance adjustment device according to claim 1 or 2, wherein,

the housing has a guide long hole formed in a length direction of the housing, and the rotation preventing member is provided with a moving pin guided along the guide long hole.

4. The nuclear fuel rod tip distance adjustment device according to claim 1 or 2, wherein,

the nuclear fuel rod clamp is screwed to the insertion rod, the insertion rod is screwed to the connector, and the nuclear fuel rod clamp is configured to be screwed to the connector.

Technical Field

The present invention relates to a nuclear fuel rod tip distance adjusting device, and more particularly, to a nuclear fuel rod tip distance adjusting device that improves convenience and accuracy of adjusting a nuclear fuel rod tip distance.

Background

The nuclear power generation structure is as follows: energy generated when nuclear fission is performed on nuclear fuel of a nuclear reactor is used for heating primary cooling water, the heated energy is transmitted to secondary cooling water and is generated into steam through a steam generator, and the steam is converted into rotational energy through a steam turbine, so that a generator generates electricity.

A nuclear reactor is a device manufactured to artificially control a chain fission reaction of a nuclear fission substance for various purposes such as heat generation, production of a radioisotope and plutonium, or formation of a radiation field.

In general, a light water reactor uses enriched uranium in which the proportion of uranium-235 is increased to 2% to 5%, and in order to process the enriched uranium into nuclear fuel for use in a nuclear reactor, a molding process of manufacturing the uranium into cylindrical pellets (Pellet) having a weight of about 5g is required.

In addition, the energy source for nuclear fission is provided by nuclear fuel.

The nuclear fuel arranged inside the nuclear reactor is constructed in units of a nuclear fuel assembly 10 as shown in fig. 1, the nuclear fuel assembly 10 includes a skeleton body composed of an upper end fixture 11, a lower end fixture 12, and a support grid 13, and nuclear fuel rods 20, which are loaded into the support grid 13 and supported by springs and dimples formed in the support grid 13.

Each nuclear fuel rod 20 includes one unit of uranium in a pellet 21 and a cladding tube 22 of zirconium alloy for protecting the uranium and preventing leakage of radioactive energy, and the nuclear fuel rod 20 is formed in a long bar shape.

In order to manufacture such a nuclear fuel assembly 10, the surfaces of the nuclear fuel rods 20 are prevented from being scratched or the support grids 13 are damaged, the surfaces of the nuclear fuel rods 20 are loaded into the skeleton bodies after painting the surfaces, and the upper end fixing bodies 11 and the lower end fixing bodies 12 are installed and fixed, thereby completing the assembly of the nuclear fuel assembly 10.

In addition, although the nuclear fuel rods 20 are loaded into the spacer grids 13 in a row unit in the process of loading the nuclear fuel assembly 10, the loaded length of the nuclear fuel rods 20 after the loading process may be different (5mm or less) depending on the characteristics of the loading process.

In view of this, in order to meet the design requirement for the tip distance of the nuclear fuel rod 20, the installation length of the nuclear fuel rod 20 needs to be adjusted using the nuclear fuel rod tip distance adjusting device.

Here, as shown in fig. 2, a conventional nuclear fuel rod end distance adjusting device 30 for adjusting the installation length of the nuclear fuel rod 20 is composed of a fuel rod clamp 31, an installation rod 32, and an installation weight 33.

The procedure of adjusting the installation length of the nuclear fuel rod 20 using the nuclear fuel rod end distance adjusting device 30 is as follows:

the nuclear fuel rod tip distance adjusting device 30 is connected to the end of the nuclear fuel rod 20, the installed length of which needs to be adjusted, by the fuel rod clamp 31.

Thereafter, the loading hammer 33 is struck in the opposite direction to the direction in which the nuclear fuel rods 20 are connected.

At this time, the loading rod 32 moves in the striking direction, and the fuel rod clamp 31 provided to the loading rod 32 pulls the nuclear fuel rod 20.

Thereafter, the loading weight 33 is struck again in the opposite direction to the connecting nuclear fuel rod 20 after returning the loading weight 33 to the original position.

The installation length of the nuclear fuel rod 20 is adjusted by repeating such processes, and the installation length of the plurality of nuclear fuel rods 20 constituting the nuclear fuel assembly 10 is adjusted by the series of processes.

However, the above-described prior art nuclear fuel rod tip distance adjusting device 30 has the following problems:

first, the adjustment of the distance of the distal end of the conventional nuclear fuel rod by the impact of the loading hammer 33 has a problem that the loading length of the nuclear fuel rod 20 cannot be finely adjusted.

That is, there may be a great difference in the moving distance of the loading hammer 33 according to the striking degree, and thus it is difficult to finely adjust the loading length of the nuclear fuel rod 20.

Secondly, the impact generated on the loading weight 33 is transferred to the nuclear fuel rod 20 during the striking of the loading weight 33, and thus there is a problem in that the nuclear fuel rod 20 may be damaged.

Again, in the process of returning the struck loading hammer 33 to the original position, the operator may inadvertently push out the loading rod 32 instead of pulling the loading rod 32, thereby possibly causing a problem in that the nuclear fuel rod 20 is pushed out.

Disclosure of Invention

Problems to be solved by the invention

The present invention has been made to solve the above problems, and an object of the present invention is to provide a nuclear fuel rod tip distance adjusting apparatus which can adjust a loading length of a nuclear fuel rod more finely and conveniently by converting a rotational motion into a linear motion, and prevent the rotational motion from being transmitted to a loading rod, thereby stably adjusting a tip distance of the nuclear fuel rod.

Means for solving the problems

In order to achieve the above object, the present invention provides a nuclear fuel rod tip distance adjusting device including: a loading rod including a nuclear fuel rod clamp and linearly moving in a front-rear direction; a hollow housing; a loading power mechanism which is arranged at the inner side of the shell, converts the rotary motion into linear motion and moves along the length direction of the shell; the connector is connected between the loading power mechanism and the loading rod; and a rotation preventing member provided between the loading power mechanism and the connector, moving in a length direction of the housing in linkage with a linear motion of the loading power mechanism, and preventing a rotational force of the loading power mechanism from being transmitted to the connector.

Preferably, the power-on mechanism is constituted by a ball screw, a rotation space in which a bolt portion of the ball screw is allowed to idle is formed at one end of the rotation preventing member, and the connector is fixed to the other end of the rotation preventing member.

Also, preferably, the housing has a guide long hole formed in a longitudinal direction of the housing, and the rotation preventing member is provided with a moving pin guided along the guide long hole.

Preferably, the nuclear fuel rod clamp is screwed to the insertion rod, the insertion rod is screwed to the connector, and the nuclear fuel rod clamp is configured to be screwed to the connector.

Effects of the invention

The device for adjusting the distance between the tail ends of the nuclear fuel rods has the following effects:

first, the structure is configured to convert a rotational motion into a linear motion using a ball screw to pull the nuclear fuel rod, thereby providing an effect of more finely adjusting the length of the installed nuclear fuel rod.

In particular, the installation length of the nuclear fuel rod is adjusted by the rotation method, thereby improving convenience of adjusting the installation length of the nuclear fuel rod.

Secondly, there is an effect that damage of the nuclear fuel rod by external force due to impact or the like can be prevented when the installation length of the nuclear fuel rod is adjusted.

Third, there is an effect that it can be easily used through the guide pin regardless of the type of the nuclear fuel.

Fourthly, the rotation of the ball screw is prevented from being transmitted to the loading rod by the rotation preventing member, so that the loading rod can be interlocked with only the linear motion of the ball screw, thereby having an effect of stably moving the nuclear fuel rod.

Drawings

Fig. 1 is a schematic view illustrating a general nuclear fuel assembly and a nuclear fuel rod.

Fig. 2 is a schematic view illustrating a nuclear fuel rod tip distance adjusting device of the related art.

Fig. 3 is a perspective view illustrating a nuclear fuel rod end distance adjusting device according to a preferred embodiment of the present invention.

Fig. 4 is a perspective view illustrating a part cut away of a nuclear fuel rod end distance adjusting device according to a preferred embodiment of the present invention.

Fig. 5 and 6 are sectional views illustrating a state in which a loading rod of a nuclear fuel rod tip distance adjusting device according to a preferred embodiment of the present invention moves forward and backward.

Fig. 7 is a use state diagram of a state where the distance of the end of the nuclear fuel rod is adjusted using the distance adjusting device of the end of the nuclear fuel rod according to the preferred embodiment of the present invention.

Detailed Description

The terms or words used in the present specification and claims are not limited to the conventional or dictionary meanings and should be interpreted as meanings and concepts conforming to the technical idea of the present invention on the basis of the principle that the inventor can appropriately define the concept of the term in order to explain his invention by the best method.

Hereinafter, a nuclear fuel rod tip distance adjusting device according to a preferred embodiment of the present invention will be described with reference to the attached fig. 3 to 7.

The technical characteristic is that the adjusting device for the distance between the tail ends of the nuclear fuel rods can utilize the working principle of the ball screw to carry out micro adjustment on the distance between the tail ends of the nuclear fuel rods, so that the convenience of adjusting the distance between the tail ends of the nuclear fuel rods can be improved.

The nuclear fuel rod tip distance adjusting apparatus according to the present invention includes: the loading bar 100, the housing 200, the loading power mechanism 300, the connector 400, and the anti-rotation member 500.

The loading rod 100 is a medium mechanism that is connected to the nuclear fuel rod 20 of the nuclear fuel assembly 10 and pulls the nuclear fuel rod 20, and the loading rod 100 includes a nuclear fuel rod tong 110.

The nuclear fuel rod clamp 110 is a member directly connected to the nuclear fuel rod 20, and an end of the nuclear fuel rod clamp 110 is formed with an attaching and detaching mechanism that can be attached to and detached from the loading rod 100.

Here, the attachment and detachment mechanism is not particularly limited, and preferably is configured to enable the nuclear fuel rod clamp 110 to be screwed to the attachment rod 100.

For example, one end of the nuclear fuel rod clamp 110 is configured in a clamp shape capable of gripping the nuclear fuel rod 20, and the other end of the nuclear fuel rod clamp 110 is configured by a bolt or a nut.

Accordingly, the loading rod 100 is also formed with nuts or bolts corresponding to the bolts or nuts of the nuclear fuel rod clamp 110, so that the nuclear fuel rod clamp 110 can be attached to or detached from the loading rod 100.

With this configuration, the length of the loading rod 100 can be adjusted by attaching or detaching the nuclear fuel rod clamp 110.

The housing 200 is configured to include various members for linearly moving the loading rod 100, and preferably, the housing 200 has a hollow cylindrical shape.

Here, both sides of the case 200 are open, the front cover 210 is provided at one end of the case 200, and the power mechanism 300 is provided at the other end of the case 200.

The front cover 210 has a guide pipe 211 for moving the connector 400, and a plurality of fitting grooves 212 for fitting the guide pins 220 are formed at the edge of the front cover 210.

The guide pin 220 is inserted into a hole of the FR guide plate, and is configured to prevent the adjustment device from rotating when the bolt part 320 for adjusting the distance of the distal end of the nuclear fuel rod is rotated.

This can be understood by means of fig. 7.

Here, a plurality of guide pins 220 having various diameters are provided, and as described above, the guide pins 220 are configured to be attachable to and detachable from the fitting groove 212 of the front cover 210.

Here, as shown in fig. 3 and 4, the front end portion of the guide pin 220 is preferably formed in a streamlined shape.

With this configuration, the guide pins 220 of various diameters can be selectively positioned in the fitting grooves 212 of the front cover 210, and thus the nuclear fuel rod tip distance adjusting device can be provided regardless of the type of nuclear fuel.

In addition, the housing 200 is formed with a guide long hole 230, and the guide long hole 230 communicates with the inside of the housing 200.

The guide long hole 230 is configured to guide a moving path when the rotation preventing member 500 moves by being incorporated in the power mechanism 300, and is formed in a long hole shape along the longitudinal direction of the housing 200.

The loading power mechanism 300 is provided behind the housing 200 to generate power for linearly moving the loading rod 100.

Preferably, the loading power mechanism 300 is configured to be able to more finely adjust the loading length of the loading rod 100.

For this, the built-in power mechanism 300 is preferably composed of a member that converts a rotational motion into a linear motion.

Thus, although not particularly limited, the ball screw assembly shown in fig. 4 is most preferable to be incorporated into the power mechanism 300.

The ball screw assembly 300 is configured to include a nut portion 310, a bolt portion 320, a plug 330, and a bearing 340.

The nut portion 310 is provided in a configuration in which the bolt portion 320 can be screwed, and includes a plurality of steel balls (not shown) rolling along a female thread.

The nut portion 310 is fixed to the housing 200 and shields the open rear portion of the housing 200.

The nut portion 310 has a cylindrical shape corresponding to the inner diameter of the housing 200.

The bolt 320 is screwed to the nut 310 and linearly moves in the longitudinal direction of the housing 200 while rotating with respect to the nut 310.

Here, one end of bolt 320 is located inside housing 200, and the other end of bolt 320 is located outside housing 200.

Here, it is preferable that the other end portion of the bolt portion 320 is provided with a handle 321, so that the bolt portion 320 can be easily gripped.

Also, the plug 330 interferes with the rotation preventing member 500 during the linear movement accompanying the rotational movement of the bolt portion 320, thereby pushing or pulling the rotation preventing member 500 or being fitted to one end portion of the bolt portion 320.

Preferably, the plug 330 has a diameter larger than that of the bolt part 320, and is preferably formed in a circular shape.

Here, it is preferable that a bearing 340 for smoothing the rotational movement of the bolt part 320 is further installed between the plug 330 and the one end of the bolt part 320.

In addition, the connector 400 functions to connect the loading rod 100 and the loading power mechanism 300.

That is, one end of the connector 400 is connected to the insertion rod 100 side, and the other end of the connector 400 is connected to the insertion power mechanism 300 side.

Here, a bolt or a nut for screwing the installation rod 100 or the nuclear fuel rod clamp 110 is formed at one end of the connector 400.

One end of the connector 400 is disposed outside the housing 200 through the guide pipe 211 and is connected to the insertion rod 100, and the other end of the connector 400 is located inside the housing 200.

In addition, the rotation preventing member 500 functions to prevent the rotational force of the bolt part 320 of the loading power mechanism 300 from being transmitted to the loading rod 100.

That is, the linear motion of the assembly power mechanism 300 is generated by the rotational motion of the bolt part 320, and when the assembly rod 100 is directly connected to the bolt part 320, the assembly rod 100 also rotates together with the bolt part 320, which may cause damage to the nuclear fuel rod 20, and the anti-rotation member 500 prevents the assembly rod 100 from rotating and allows the assembly rod 100 to perform only the linear motion.

Thus, the rotation preventing member 500 moves inside the housing 200 in the longitudinal direction of the housing 200 in conjunction with the linear motion generated by the rotational motion of the bolt portion 320.

One end of the rotation preventing member 500 is fitted to the bolt 320, and the other end of the rotation preventing member 500 is fitted to the connector 400.

The rotation preventing member 500 will be described in detail below.

One end of the rotation preventing member 500 is formed with a rotation space 510, the rotation space 510 is configured to fit and idle the plug 330 of the power mechanism 300, and the rotation space 510 is formed in a cylindrical shape corresponding to the inner diameter of the housing 200.

Here, the rotation preventing member 500 further includes a shielding cap 520 shielding the rotation space 510, and a through hole 521 for passing the bolt portion is formed in the shielding cap 520.

That is, by being constructed as above, the plug 330 and the bearing 340 are located in the rotation space 510 of the rotation preventing member 500, and the shielding cap 520 shields them.

The other end of the rotation preventing member 500 is formed with a fixing mechanism for fixing the connector 400.

Preferably, the fixing mechanism is also configured to be able to be screwed with the connector 400, but is not limited to this configuration.

The rotation preventing member 500 is provided with a moving pin 530 which is guided along the guide long hole 230 of the housing 200 in the process of linearly moving inside the housing 200.

Hereinafter, a process of adjusting the installation length of the nuclear fuel rod using the nuclear fuel rod end distance adjusting device composed of the above-described members will be described.

A plurality of nuclear fuel rods 20 are installed in the support grids 13 of the nuclear fuel assembly 10.

Here, the distance of the end of the installed nuclear fuel rod 20 may be uneven, and the operator adjusts the distance of the end of the nuclear fuel rod 20 using the nuclear fuel rod end distance adjusting device.

For this purpose, the guide pin 220 is attached to the front cover 210 of the housing 200, and as shown in fig. 7, the guide pin 220 is fitted to an FR guide plate of the nuclear fuel assembly workstation.

Thus, as shown in fig. 7, the nuclear fuel rod tip distance adjusting device is fixed to the FR guide plate of the nuclear fuel assembly assembling table, and the loading rod 100 faces the nuclear fuel rod 20 accordingly.

Here, it can be understood that the size of the guide pin 220 and the position of the guide pin 220 on the front cover 210 of the housing 200 may be adjusted according to the type of nuclear fuel.

Also, the length of the loading rod 100 may be adjusted in consideration of the interval between the FR guide plate of the nuclear fuel assembly assembling table and the nuclear fuel rod 20.

Both end portions of the loading rod 100 are screwed to the nuclear fuel rod clamp 110 and the connector 400 by the attachment and detachment mechanism, respectively, and the length of the loading rod 100 can be shortened by directly screwing the nuclear fuel rod clamp 110 to the connector 400.

That is, the length of the loading rod 100 can be increased or decreased according to the distance between the FR guide plate of the nuclear fuel assembly assembling table and the nuclear fuel rod 20.

Next, the end of the nuclear fuel rod 20 to be adjusted is gripped by the nuclear fuel rod clamp 110 of the loading rod 100 corresponding to the nuclear fuel rod 20.

Then, the handle 321, which is the bolt portion 320 of the ball screw incorporated in the power mechanism 300, is gripped and the bolt portion 320 is rotated.

Here, as shown in fig. 5 and 6, the rotation direction of the bolt portion 320 is a direction in which the loading rod 100 can be pulled to the right in the figure.

When the bolt part 320 is rotated, it moves linearly along the screw of the nut part 310, and at this time, the plug 330 fitted to the end of the bolt part 320 rotates in the rotation space 510 of the rotation preventing member 500, and pulls the shielding cap 520 of the rotation preventing member 500.

Thereby, as shown in fig. 6, the rotation preventing member 500 is interlocked in the linear movement direction of the bolt portion 320, and moves along the longitudinal direction of the housing 200.

At this time, the moving pin 530 of the rotation preventing member 500 moves along the guide long hole 230, and guides the stable movement of the rotation preventing member 500.

Further, the connector 400 fitted to the rotation preventing member 500 moves the insertion rod 100 in the moving direction of the bolt portion 320 by the movement of the rotation preventing member 500.

Here, the connector 400 is not directly connected to the bolt part 320 but connected to the rotation preventing member 500, and thus does not move linearly in conjunction with the rotation of the bolt part 320 but only moves linearly in accordance with the linear movement of the bolt part 320.

Accordingly, the nuclear fuel rod 20 connected to the loading rod 100 is linearly moved only by the movement of the connector 400.

Here, it can be understood that the rotation range of the bolt part 320 for adjusting the tip distance of the nuclear fuel rod 20 can be adjusted by an operator, and the movement of the loading rod 100 can be finely adjusted by the rotation motion of the bolt part 320, so that the accuracy of the tip distance adjustment of the nuclear fuel rod 20 can be improved.

As described above, the distance adjusting device for a nuclear fuel rod distal end according to the present invention is technically characterized in that the distance adjusting device for a nuclear fuel rod distal end is configured to be incorporated into a power mechanism for converting a rotational motion into a linear motion, thereby enabling a distance of a nuclear fuel rod distal end to be adjusted more finely.

In particular, when the linear motion generated according to the rotational motion is changed, the insertion rod connected to the nuclear fuel rod does not perform the rotational motion but performs only the linear motion, so that the tip distance of the nuclear fuel rod can be stably adjusted without damaging the nuclear fuel rod.

Thus, convenience and accuracy of adjusting the distance of the end of the nuclear fuel rod can be improved.

While the specific embodiments of the present invention have been described in detail, it will be apparent to those skilled in the art that various changes and modifications can be made within the scope of the technical spirit of the present invention, and these changes and modifications naturally fall within the scope of the appended claims.

Description of the reference numerals

100: loading stick

110: nuclear fuel rod clamp

200: shell body

210: front cover

211: catheter tube

212: tabling groove

220: guide pin

230: guide slot

300: power mechanism of packing into

310: nut part

320: bolt part

330: plug for bottle

340: bearing assembly

400: connector with a locking member

500: anti-rotation member

510: rotating space

520: shielding cap

521: through hole

530: moving pin