CN214476442U - Foldable radiation shielding device - Google Patents

Abstract

The utility model belongs to the nuclear radiation field, concretely relates to folded cascade radiation shield assembly. The shielding material in the prior art is heavy and occupies a large space. The square joints of two single-end ratchet support arms of the device are inserted into square slots in the L-shaped joints of the tail end connecting support arm parts, and two ends of a connecting cross rod are connected with the L-shaped joints of the two single-end ratchet support arms through screws B; the square joints of the ratchets at one ends of the two double-head ratchet support arms are respectively inserted into the square grooves in the L-shaped joints of the end connecting support arm parts, and then the square joints of the ratchets at the other ends of the two double-head ratchet support arms are respectively inserted into the square grooves in the L-shaped joints above the single-head ratchet support arm side parts. The device has strong advantages in the aspects of safety performance, stability performance, convenience performance, personnel radiation dose control and the like.

Description

Foldable radiation shielding device

Technical Field

The utility model belongs to the nuclear radiation field, concretely relates to folded cascade radiation shield assembly.

Background

Almost all the radioactivity of the pressurized water reactor nuclear power plant comes from an active area of a reactor loaded with fuel assemblies, and along with the operation of the nuclear power plant, corrosion activation products are continuously deposited on the inner walls of equipment, valves and pipelines of a main system and an auxiliary system thereof to form points or local positions with strong radioactivity, which are often called as radioactive hot spots (hot spots for short). The radiation level of the hot spots is high and not easy to eliminate, the formed strong penetrating radiation is the main reason of the increase of the radiation level of partial buildings or areas of the nuclear power plant, high radiation dose can be caused to maintainers near the hot spots, and small dose accumulation can be caused to other workers near the hot spots, so that the overall collective dose of the power plant is increased.

In order to reduce the influence of the radioactive heat points on the radiation dose of personnel, ensure the radiation safety of field workers and improve the radiation safety management level of a power plant, temporary shielding is a relatively common optimization measure in radiation protection management of a nuclear power plant. However, in practical application, it is found that a power plant has more radioactive hot spot pipelines or equipment which are close to the ground and close to the wall, and the difficulty of effectively implementing radiation shielding measures for the hot spots is higher, mainly because no radiation shielding device which is effectively applicable is available at home and abroad at present, the existing shielding mode has many limitations, and the requirements on safety influence on system equipment, operation convenience, radiation dosage reduction of operators and the like are difficult to be considered. The main embodiment is as follows:

the shielding mode of directly covering the hot spot by using the shielding material is convenient to operate and the radiation dose to the operator is low, but the shielding material is generally heavy and difficult to fix, so that hot spot equipment can be damaged, the safety of a nuclear power plant process system is affected, and the shielding material is gradually replaced at present;

the mode of erecting a scaffold as a support and then hanging shielding materials can avoid loading on equipment pipelines, but the mode needs to occupy larger space, has large workload, long operation time and larger radiation dosage to operators, and meanwhile, the mode needs other departments to erect the scaffold in advance, so that the effectiveness is poor, and the mode is very inconvenient to dismantle and reassemble temporarily if needed.

Therefore, in order to effectively solve the problem of shielding the radioactive hot spots and better apply radiation shielding measures, starting from the requirement of optimal management of radiation protection of the power station, a set of radiation shielding device which not only meets the radiation protection requirement on shielding performance, but also has stronger safety and stability and can obviously reduce the radiation dose of shielding operators is needed to be designed and manufactured.

Disclosure of Invention

1. The purpose is as follows:

the utility model aims to develop one set of folded cascade radiation shield assembly, its main function has four aspects: firstly, the shielding material is physically isolated from the hot spot equipment to be shielded, so that the hot spot equipment is prevented from being damaged due to the weight of the shielding material, and meanwhile, the device has stronger stability and firm stability within a rated load range; secondly, the shielding material (soft lead screen) commonly used in a nuclear power plant can be matched, the resource cost is saved, and different shielding performance requirements can be met by hanging different amounts of shielding materials according to the radiation source dosage rate level; thirdly, the operation requirements of quick installation and removal are met due to the strong convenience, and the main body part can be installed in a low-radiation area, so that the workload near the radioactive hot spot is reduced, and the radiation dose of operators is reduced; fourthly, the device has strong universality, can meet the shielding requirements of hot spots in various positions and different types through different changes of the structure, and can be combined and applied by a plurality of devices to expand the application range.

2. The technical scheme is as follows:

an object of the utility model is to provide a folded cascade radiation shielding strutting arrangement, solve nuclear power plant press close to ground, especially be close to the radioactive heat point radiation shielding of wall limit or equipment and use a difficult problem, shielding arrangement has stronger advantage in aspects such as security performance, stability ability, convenient performance and personnel radiation dosage control simultaneously.

A foldable radiation shielding device is characterized in that two ends of a connecting cross rod are screwed into threaded holes at the sides of L-shaped joints of two tail end connecting support arms respectively; the bottoms of the two tail end connecting support arms are fixed with the two ends of the tail end connecting rod of the support through a screw A and a nut respectively; the square joints of the two single-head ratchet support arms are inserted into square slots in the L-shaped joints of the tail end connecting support arm parts, and two ends of the connecting cross rod are connected with the L-shaped joints of the two single-head ratchet support arms through screws B; the square joints of the ratchets at one ends of the two double-head ratchet support arms are respectively inserted into the square grooves in the L-shaped joints of the end connecting support arm parts, and then the square joints of the ratchets at the other ends of the two double-head ratchet support arms are respectively inserted into the square grooves in the L-shaped joints above the single-head ratchet support arm side parts.

The two ends of the double-end ratchet wheel support arm are both square joints, and columnar bulges are arranged on the square joints.

One end of the single-end ratchet wheel support arm is a ratchet wheel joint, and the other end of the single-end ratchet wheel support arm is an L-shaped joint; the ratchet joint is provided with a columnar bulge; one side of the L-shaped joint is provided with a square slot, and the other side of the L-shaped joint is provided with two threaded holes.

One end of the tail end connecting support arm is an L-shaped joint side, the left side of the L-shaped joint side is a square slot, and the right side of the L-shaped joint side is a threaded hole; the center of the bottom of the tail end connecting support arm is provided with a groove, and both sides of the groove edge are respectively provided with a through hole.

And two ends of the connecting cross rod are provided with threaded joints.

The two ends of the connecting rod at the tail end of the support are both narrow joints, screw holes are formed in the middle and the two ends of the connecting rod, and each screw hole is perpendicular to the cross section of each narrow joint.

One threaded hole of the single-end ratchet wheel support arm is used for fixing, and the other threaded hole is connected with the arc-shaped hook.

3. The effect is as follows:

the foldable radiation shielding device described in the utility model can be used alone or in combination, thereby realizing the shielding requirements of ground pipelines or equipment with different lengths, different heights and different positions without affecting the system function; when the foldable radiation shielding device described in the utility model is set up, compared with a shielding setting mode that scaffolds are adopted as supports in the same scale, the workload and the operation time are both greatly reduced (at least more than 1 time), and the workload near the hot spot is small, so that the radiation dose of shielding operators can be greatly reduced; the utility model discloses the folded cascade radiation shield assembly bearing capacity who describes in is strong, can realize higher shielding performance to reduce near the focus and lead to personnel's small dose accumulation, reduce the holistic collective dosage of nuclear power plant.

Drawings

FIG. 1 double-head ratchet arm

FIG. 2 a single-ended ratchet arm

FIG. 3 end connecting arm

FIG. 4 connecting rail

FIG. 5 Stent end Link

FIG. 6 is a view showing the mounting of end connection arm parts

FIG. 7 is a view showing the mounting of a side member of a single-ended ratchet arm

FIG. 8 is a side part mounting view of a double-headed ratchet arm

FIG. 9 folding radiation shield assembly

FIG. 10 is a folded version of the radiation shield

FIG. 11 illustrates an exemplary L-shaped application of the shielding device

FIG. 12 exemplary use of the shielding device in the inverted V-shape

FIG. 13 examples of other uses of the shielding device

In the figure: 1. the double-end ratchet support arm 2, single-end ratchet support arm, 3, end connection support arm, 4, screw A, 5, nut, 6, support end connecting rod, 7, connection horizontal pole, 8, arc couple, 9, screw B.

Detailed Description

1. The utility model discloses a following technical scheme realizes:

the foldable radiation shielding device consists of 2 double-head ratchet support arms, 2 single-head ratchet support arms, 4 tail end connecting support arms, 3 connecting transverse rods, 2 support tail end connecting rods, 16 arc-shaped hooks and 6 groups of bolts and nuts. The double-end ratchet support arm, the single-end ratchet support arm, the tail end connecting support arm, the connecting cross rod and the support tail end connecting rod can be assembled into an integral device (the integral device is not required to be disassembled during use), the arc-shaped hook is a standard accessory, and the arc-shaped hook is pre-installed (installed through threaded connection) during use according to needs.

The dimensional parameters of each part are as follows:

the total length of the double-ended ratchet arm is 465mm, the two ends are 1-inch ratchet joints, and the middle part is welded with the two ratchet joints into a whole by using a connecting rod. The connecting rod is made of SUS304 stainless steel, and is 200mm long and 36mm in diameter.

The total length of the single-ended ratchet arm is 432mm, one end is a 1-inch ratchet joint, the other end is an L-shaped joint, and the two joints are welded together by a connecting rod in the middle. The L-shaped joint has the overall length, width and height of 132mm multiplied by 74mm multiplied by 65mm, the side edge of the narrow surface is 32cm in thickness and is provided with an M8 screw hole (used for installing an arc-shaped hook), the side edge of the top is provided with two M8 screw holes (one used for fixing and one used for installing the arc-shaped hook), the side edge of the wide surface is provided with a square hole of 25.5mm multiplied by 25.4mm multiplied by 17mm in effective depth, and the other surface adopts an M18 screw hole of 15mm in effective depth to penetrate through the whole side edge; the connecting rod is made of SUS304 stainless steel, 170mm in length and 36mm in diameter.

The total length of the end connecting arm is 450mm, and the end connecting arm comprises an L-shaped joint (as above) and is integrally finished by CNC (computer numerical control) machining and is made of 6065 aluminum alloy. The center of the bottom of the connecting rod is provided with a groove with the width of 12mm and the depth of 40mm, and both sides of the groove edge are respectively provided with a through hole with the diameter of 9mm (the distance between the center of the hole and the bottom edge is 18 mm).

The total length of a connecting rod at the tail end of the support is 472mm, the diameter of the connecting rod is 36mm, the material of the connecting rod is 6065 aluminum alloy, two ends of the connecting rod are narrow joints with the length of 40mm, the width of 36mm and the thickness of 12mm, and through holes with the diameter phi of 9mm are formed in the middle of each of the two joints (the distance between the centers of the two holes is 428 mm); the middle part and the two ends of the connecting rod at the tail end of the bracket are respectively provided with 1M 8 screw holes (the center distance between the screw holes at the two ends is 336mm), and each screw hole is vertical to the cross section of the narrow joint.

The total length of the connecting cross bar is 346mm, the diameter is 36mm, the material of the cross bar is 6065 aluminum alloy, and both ends of the cross bar are M18 threaded joints (the effective length of the threads is 15 mm).

The total length of the arc-shaped hook is 77mm, the arc-shaped radius of the hook is 20mm, the thickness of the hook is 8mm, the other end of the hook is provided with M8 threads, and the length of the threads is 24 mm.

The foldable radiation shield is assembled in one piece with a single lateral wall dimension of 836mm in length and 472mm in width.

(1) Design in radiation shielding performance

The shielding performance of a foldable radiation shielding device is mainly dependent on the installed shielding material thickness, i.e. directly related to the shielding material weight that the device can carry. The shielding material commonly used in nuclear power plants is a soft lead shield with a lead equivalent of 5mmPb and containing two common specifications of 40cm x 40cm (about 12.5kg) and 40cm x 80cm (about 25 kg). The maximum load weight of the single foldable radiation shielding device is determined to be 200kg after all factors are considered comprehensively.

For the Λ -type arrangement, the two arms can each bear 100kg (4 layers of soft lead screen, 20mm lead equivalent) at maximum, corresponding to about 3 times the half-value layer protection thickness of Cs-137 gamma ray (0.662Mev) and about 1.7 times the half-value layer protection thickness of Co-60 gamma ray (1.25 Mev).

For the setting mode of the type of 'angle', the maximum weight of the upper support arm can be 200kg (8 layers of soft lead screens, 40mm lead equivalent), which is about 6.7 times of the thickness of the half-value layer of Co-60 gamma rays (1.25 Mev).

In practical application, the quantity of the shielding materials can be increased or decreased according to needs so as to meet different shielding performance requirements.

(2) Design of safety aspects

The foldable radiation shielding device is of an integrated structure, and has fewer scattered parts, so that the foldable radiation shielding device is convenient for the foreign matter protection and control of a working site.

The foldable radiation shielding device adopts a gap bridge type installation mode, so that the shielding material is prevented from being in direct contact with the hotspot equipment, and the load safety influence on the system equipment can be avoided.

The foldable radiation shielding device provides an index of the maximum load bearing capacity, the weight of the shielding material can be controlled through quantitative standards, and the use safety of the device is ensured.

The work load required for building the foldable radiation shielding device on site is less, the operation time is short, and the radiation dose of operators can be obviously reduced.

(3) Design in convenience

Folded cascade radiation shield assembly back can regard as a whole to use, need not additionally to install the operation except that the arc couple (the arc couple is standard accessories, installs as required during the use), only needs adjusting device structure and installation arc couple during the field usage, and the operation is very convenient.

The foldable radiation shielding device is low in operation difficulty, operators can master the use requirements skillfully through simple training, cooperation work of other departments is not needed, and effectiveness of radiation shielding work is high.

The total weight of the foldable radiation shielding device is about 10Kg, a single person can easily complete the carrying and dismounting operation, the support arms at the two sides of the device can be folded, the occupied space is small, and the device is convenient for on-site storage and management.

(4) Design in terms of economy and versatility

The foldable radiation shielding device can be directly matched with shielding materials (soft lead screens) commonly used in a nuclear power plant for use, the soft lead screens with two commonly used specifications of 40cm x 40cm and 40cm x 80cm can be matched (other specifications can be applied when the distance between suspension holes is about 336mm), the shielding materials do not need to be additionally purchased, and the resource cost can be saved.

Folded cascade radiation shield assembly can realize multiple using-way to different hot spot characteristics, has stronger commonality, and the common mode has:

when the radioactive hot spot line or device is in an open position, the radiation shield can be adjusted to be "Λ" (shield outer diameter not more than 70cm high) or "pi" (shield outer diameter not more than 35cm high) for use;

when the radioactive hot spot pipeline or equipment is positioned at the wall side or other equipment side, the radiation shielding device can be adjusted to be in an 'angle' type (the included angle between two arms can be adjusted) for use, and the height of the outer diameter of the pipeline can be shielded to be up to 110 cm;

the support arms on both sides of the device can be folded from the middle part, and the support arms on both sides can be adjusted according to the height of a hot spot and the like, so that more using modes are realized.

When the hot spot pipeline that needs the shielding is longer, can adopt many sets of device combination to use, put each shield assembly one by one in advance along the pipeline trend, hang shielding material in proper order again and can accomplish the operation, the bigger price/performance ratio of shielding scope is higher.

2. The installation steps of the device are as follows:

(1) foldable radiation shield installation

Step 1: two end connecting arms 3 (fig. 3), 1 connecting cross bar 7 (fig. 4) and 1 support end link 6 (fig. 5) were selected. Screwing the two ends of the connecting cross rod 7 into threaded holes at the L-shaped joint sides of the two tail end connecting support arms 3 respectively until the two tail end connecting support arms are screwed tightly; the bottoms of the two end connecting support arms 3 and the two ends of the support end connecting rod 6 are respectively screwed and fixed through bolts and nuts, and the complete installation of one end connecting support arm 3 component is completed (fig. 6).

Step 2: and (5) repeating the step (1) again to complete the complete installation of the other end connecting arm 3 component.

And step 3: two single-ended ratchet arms 2 (fig. 2), 1 connecting cross bar 7 (fig. 4) and 1 assembled end connecting arm 3 assembly (fig. 6) were selected. The square joints of the two single-head ratchet support arms 2 are inserted into the square slots in the L-shaped joints of the tail end connecting support arm parts 3, and simultaneously, the two ends of the connecting cross rod 7 are screwed into the threaded holes at the side of the L-shaped joints of the two single-head ratchet support arms 2 respectively until being screwed tightly. The top of the L-shaped joint of the two single-end ratchet arms 2 is fixed by screwing the bolt of M8. The single-head ratchet arm 2 side part mounting is completed (fig. 7).

And 4, step 4: two double-ended ratchet arms 1 (fig. 1), 1 assembled end connecting arm 3 part (fig. 6), and 1 assembled single-ended ratchet arm 2 side part (fig. 7) were selected. The square joints of the ratchets at one ends of the two double-head ratchet support arms 1 are respectively inserted into the square grooves in the L-shaped joints of the end connecting support arm parts (figure 8), and then the square joints of the ratchets at the other ends of the two double-head ratchet support arms 1 are respectively inserted into the square grooves in the L-shaped joints above the parts of the single-head ratchet support arm 2. And finally, respectively screwing and fixing the joints of the four ratchet wheel square joints and the four square joint slots by using M8 bolts. The installation of the complete set of devices is completed (fig. 9).

The foldable radiation shielding device can be integrally used and stored after being assembled, and does not need to be disassembled additionally. The whole device can be folded for storage or carrying, and the storage space can be reduced (figure 10). The arc-shaped hook 8 can be installed as required when in use and can be independently stored at ordinary times.

(2) Use of foldable radiation shielding device

1) Radiation shielding scheme determination

And determining the range of shielding measures according to the spatial position and the influence area of the radioactive hot spot, and determining the number of the required radiation shielding devices.

According to the dose rate level of the hot spot to be shielded, the expected dose rate level, the load bearing capacity of the shielding device and the shielding performance data of the shielding material, the quantity of the shielding material (soft lead screen) to be adopted is determined, and sufficient shielding material is prepared.

2) Method for using device

According to the structural characteristics of hot spots, the installation mode of the shielding device is adjusted in a field low-radiation area, and meanwhile, the arc-shaped hook is installed at the position where the soft lead screen needs to be hung on the shielding device.

The shielding device can realize a plurality of using modes according to the situation of the field hot spot, and the specific method is approximately similar to that of the following steps: firstly, the shielding device is arranged above or on the side of a hot spot, and then a certain amount of soft lead screen is hung on the arc-shaped hook to complete installation. For longer hot spot pipelines or equipment, a plurality of sets of radiation shielding devices can be arranged according to the length and the trend of the pipelines, and finally the soft lead screens are hung in sequence, so that the soft lead screens hung by adjacent shielding devices are required to be overlapped as much as possible, and the shielding performance is prevented from being influenced by gaps. When the shielding device is dismounted, the soft lead screen is firstly dismounted, and then the shielding device is taken back in sequence.

Several types of commonly used methods are as follows:

a) the use mode of the 'unders' type is mainly used for radioactive hot spots close to the wall edge or other equipment.

The included angle between the two arms of the use mode of the < - > type is adjustable, and the two arms can be folded from the middle part, and the structure can be adjusted according to the height of the pipeline and the distance between the pipeline and the wall, so that various usages are realized (as shown in fig. 11).

b) The 'inverted V' use mode is mainly used for radioactive hot spots at a certain height in an open area.

When the hot spot is higher (the height of the outer diameter is not more than 70cm), the shielding device can be directly placed above the hot spot according to the figure 12-1, and then the soft lead screen is hung;

when the hot spot is low (the height of the outer diameter does not exceed 35cm), the two arms of the shielding device can be folded (fig. 12-2), the shielding device is placed above the hot spot, the soft lead screen is hung, and finally the two folded end connecting arms are pressed against the soft lead screen.

c) Other modes of use

The shielding device can be adjusted in different ways according to the hotspot characteristics and the use requirements, such as adjusting the shielding device into a "pi" configuration (fig. 13).

Claims (7)

1. A foldable radiation shield, comprising: two ends of the connecting cross rod (7) are screwed into threaded holes at the side of the L-shaped joints of the two tail end connecting support arms (3) respectively; the bottoms of the two tail end connecting support arms (3) are fixed with the two ends of a support tail end connecting rod (6) through screws A (4) and nuts (5) respectively; the square joints of the two single-head ratchet support arms (2) are inserted into square slots in the L-shaped joints of the tail end connecting support arm (3), and two ends of the connecting cross rod (7) are connected with the L-shaped joints of the two single-head ratchet support arms (2) through screws B (9); the square joints of the ratchets at one ends of the two double-head ratchet support arms (1) are respectively inserted into the square grooves in the L-shaped joints of the parts of the tail end connecting support arms (3), and then the square joints of the ratchets at the other ends of the two double-head ratchet support arms (1) are respectively inserted into the square grooves in the L-shaped joints above the parts of the single-head ratchet support arms (2).

2. Foldable radiation shielding device according to claim 1, characterized in that: the two ends of the double-end ratchet wheel support arm (1) are both square joints, and columnar bulges are arranged on the square joints.

3. Foldable radiation shielding device according to claim 1, characterized in that: one end of the single-end ratchet wheel support arm (2) is a ratchet wheel joint, and the other end of the single-end ratchet wheel support arm is an L-shaped joint; the ratchet joint is provided with a columnar bulge; one side of the L-shaped joint is provided with a square slot, and the other side of the L-shaped joint is provided with two threaded holes.

4. Foldable radiation shielding device according to claim 1, characterized in that: one end of the tail end connecting support arm (3) is an L-shaped joint side, the left side of the L-shaped joint side is a square slot, and the right side of the L-shaped joint side is a threaded hole; the bottom center of the tail end connecting support arm (3) is provided with a groove, and both sides of the groove edge are respectively provided with a through hole.

5. Foldable radiation shielding device according to claim 1, characterized in that: and two ends of the connecting cross rod (7) are provided with threaded joints.

6. Foldable radiation shielding device according to claim 1, characterized in that: both ends of the connecting rod (6) at the tail end of the bracket are narrow joints, screw holes are formed in the middle and both ends of the connecting rod, and each screw hole is perpendicular to the cross section of each narrow joint.

7. Foldable radiation shielding device according to claim 1, characterized in that: one threaded hole of the single-end ratchet wheel support arm (2) is used for fixing, and the other threaded hole is connected with an arc-shaped hook (8).

Images