JPS58134889A - Lining vessel and its building method - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION (Technical Field of the Invention) The present invention relates to a lined container provided with a metal lining, such as a carbon steel plate lining or a suonless steel plate lining, and a method for constructing the same.

Metal linings for lining containers are widely used in nuclear facilities, general chemical plants, etc. An explanation will be given below using as an example a stainless steel plate-lined container for storing radioactive waste from a nuclear power plant facility.

(Description of Prior Art) Concrete-walled containers lined with lychee plates such as stainless steel plates are used in radioactive material storage tanks such as fuel pools, equipment storage bits, and waste liquid storage tanks in nuclear power plants. .

When installing the lining board on the inside of the concrete wall, embed the mounting hardware in advance so that it is exposed on the wall surface, and then weld the lining board to the mounting hardware. However, in such a configuration, a gap is created between the concrete wall and the lining plate. This gap is usually 5fil
If the lining plate is damaged for some reason even though it is within III, the activated sludge inside the container will leak VT4 and accumulate in the four spaces above, and some of the leaked liquid will penetrate into the concrete wall. This increases the amount of leakage,
Contaminated area expands. In addition, damage to the lining board must be detected early and appropriate repairs must be made, but in this case, the pJi distance between the concrete wall and the lining board must be
C/7 Removal of the radioactive liquid is extremely difficult as the liquid penetrates and adsorbs into the concrete.

However, if this IT is left unused, there is a risk that workers repairing the lining boards will be exposed to large amounts of radiation. Furthermore, condensation tends to occur on the back surface of the lining plate due to the difference in degrees between the stored material and the concrete wall, and there is also the problem that it is difficult to distinguish between such condensation and liquid leakage.

In addition, in order to solve these problems, various types of double-lined containers, which have a structure in which the lining plates are simply doubled, have been adopted, but the structure is complicated and requires a lot of materials, making it difficult to construct. There were other problems. In order to solve this double-lined container problem, a lined container is manufactured in advance at a factory, etc., and this container is used as a substitute for concrete, and concrete is poured around it to construct the lined container 1fr: all at once. (hereinafter abbreviated as block construction method) is sometimes used, but due to the large amount of electricity and bulk, it is not used for large-sized lined containers due to transportation restrictions. Lining plates are an alternative construction method for construction work. Because it is a material, it must be handled roughly, causing dents and abrasions on the front and back surfaces of the lining plate, and in severe cases, there is a risk of causing defects that are unusable, resulting in physical and personal injury.

Furthermore, with the block construction method, there is no guarantee that the poured concrete will reach every corner of the back of the lining board (filling), and bubbles and contaminants may cause defects in the concrete on the back of the lining board. This defect significantly reduces the strength of the lining plate against the internal pressure of the accumulated material, but defect inspection can be detected by the impact echo sound from the lining plate surface, but it is far from perfect and requires a huge amount of inspection time. I need. In addition, even if the size and location of the defect are limited as a result of the inspection, the reality is that there is no effective repair method, so it is necessary to increase the thickness of the lining board by anticipating the size of the defect in advance, which results in wasted materials. Yes, and the amount of electricity was increasing.

(Object of the invention) The present invention has been made in view of the above circumstances.
The purpose is to spread the leaked liquid that has accumulated in the gap between the concrete wall and the lining plate over a wide area.It also prevents condensation, allows accurate and prompt detection of leaks, and enables quick and safe repair in the event of damage. To provide a lined container that can be easily and easily damaged, and a construction method that safely and easily constructs the lined container.

That is, the container has a multi-lined structure including a thin lining plate, and the IIIP feature is that the lining plate on the concrete side can be easily constructed using a thin coiled steel plate.

(Structure of the Invention) The present invention will be described below with reference to the M side of an embodiment. Figure 1 shows the wall of a concrete frame that stores radioactive waste from a nuclear power plant facility, with stainless steel IM terracing on the bottom and a drain hole in the center of the bottom with a capacity of several hundred to several thousand cubic meters. A bird's-eye view of the lining container with
The figure is partially cut away for easy viewing. The lining container 1 has a concrete wall 2 with a thickness of 4 m to 6 m.
Surface lining plate 3 made of stainless steel plate of about mm
It is formed by lining multiple layers and welding them together watertight.

The side wall portion and the bottom portion of the concrete wall 2 have a mounting bracket 4 made of KdH section steel or the like that is flush with the concrete wall 2, and
A plurality of weld lines 3a of the surface lining plate 3 are buried in both the horizontal and vertical directions. A plurality of rod-shaped anchors 5 are welded at regular intervals to the back surface of this mounting bracket 4, and the mounting bracket 4 is firmly fixed to the concrete wall 2Vc. I try to do that. Since the surface lining plate 3 is the lifeline of the lined container, it goes without saying that the material should be carefully selected, but in particular, by making the entire surface smooth, corrosion resistance is improved and decontamination of the layered radioactive material is facilitated. Therefore, we use a stainless steel lining plate that has been manufactured using cold pressing equipment to have an extremely smooth surface. Stainless steel sheets finished by cold rolling have residual compressive stress inside the material, so they are highly resistant to stress corrosion cracking, which is expected to be the most likely cause of failure in lined containers. have power. Due to the manufacturing limits of the width and length of this cold-rolled stainless steel plate, a plurality of front lining plates 3 are welded to the side walls and bottom of the body together with a back lining plate 6 (described later) to the protruding surface of the mounting bracket 4. 3a and is airtightly attached. The uppermost fitting 4 is located at the upper end of the surface lining plate 3, and the upper edge of the surface lining plate 3 is continuously welded to the uppermost fitting 4 in a watertight manner.

The back lining plate 6 (see Fig. 2a) is a cold-rolled stainless steel plate that can be wound into an extremely thin coil with a thickness of about 0.05W to 1.01W, which is wider than the width of the front lining plate 3 by its own overlap. , both the mounting brackets 4
Also, the surface lining plates 3a are sandwiched between the concrete wall 2 and the surface lining plate 3, and the surface lining plates 3 are attached to the mounting bracket 4 by mutual welding 3a. It is firmly hermetically welded to the metal fitting 4 together with the surface lining plate 3. The longitudinal dimension of the surface lining plate 6 can be made long regardless of the longitudinal dimension of the surface lining plate 3. For example, in the case of a wall, the lining container wall is composed of one long plate from the upper end to the lower end.

Next, we will explain the detailed construction method of the lined container. When pouring concrete for the concrete wall 2 of the bottom and wall portions, the concrete form (not shown) and the mounting bracket 4 are tightly fixed with bolts, and the concrete is poured.
When the bolts are loosened after the concrete hardens and the form is dismantled, the mounting bracket 4 with the rod-shaped anchor 5 becomes flush with the concrete wall 2 (-one plane), and the surface lining plates 3 are welded together [ 3a, the surface lining @3 and the coplanar lining plate 6 are laid out on the concrete wall so that they can form a layer. The width of the surface lining plate 3 (1 in Figure 1) is attached to the concrete wall 2 where the mounting bracket 4 is prepared
The back lining plate 6, which is slightly wider than the sum of the width (indicated by a l) and the groove size of the mutual joints 3a of the front lining plates, is attached to the curtain sequentially from top to bottom while unwinding the coil. Then, spot weld it to the exposed surface of the mounting bracket 4 to temporarily fix it. At this time, the back lining plate 6 is cut at a predetermined position near the bottom surface using a portable easy-to-cut tool such as metal scissors. In this case, the practical limit plate thickness that can be easily cut and the cutting speed) is approximately 1.0
It is a temple. First, if the plate thickness exceeds 10 mm, the inner diameter of the coil will increase and the weight will increase, making the work difficult. This laying operation is repeated one after another to cover the wall of the lining container, but at this time, the back lining plates 6 must be installed so that they overlap each other at the mutual weld 11eaa of the front lining plates except for the uppermost edge of the back lining plates 6. Must be. Furthermore, the back lining plate 6 is similarly laid over the entire surface of the bottom and corner portions so as to overlap once. The corner lining plate 6 is thin and can be easily bent on site without having to be bent using a pigeon in advance.

Next, a step begins in which a plurality of surface lining plates 3 are attached to the side and bottom surfaces. As mentioned above, this stainless steel plate needs to have a smooth surface.

It is more advantageous to use a material manufactured in continuous cold rolling equipment with high physiological properties. Further, the back lining plate 6 also uses a coil-shaped thin cold-rolled stainless steel plate manufactured in a continuous cold-rolling facility. In any of the above mentioned lining plates, the manufacturing limit for cold rolled stainless steel sheets is extremely low (1550cm), which is related to the equipment of domestic steel manufacturers except in special cases.
(approximately 5 feet), and in practical terms, a coiled thin stainless steel plate can be manufactured to an infinitely long length.

Therefore, the standard of the surface lining plate 3 is set to 1500, and the actual plate width is 1490 after subtracting the weld groove numerator Omm.
) If the width of the back lining plate 6 is set to 1550 mm, the overlap between the back lining plates 6 will be 50 mm.
Since it is possible to secure the connection, it is possible to efficiently utilize the highly productive continuous cold rolling equipment to its fullest extent, and it has the effect of shortening the total length of the welding line of the 1-surface lining plate Aihiro Yoshitsu 3a. .

If a stainless steel plate with a width of 1550+W or more is used, it will be possible to use a highly efficient screen material, and it seems possible to further shorten the length of the welding process, but discontinuous heat treatment with poor productivity The wide stainless steel sheets manufactured using inter-rolling equipment undergo several stages of polishing using an abrasive.
It is necessary to smooth the surface, and this operation is not only expensive and time-consuming and impractical, but also the surface finish and condition are undeniably inferior to that of continuously cold-rolled material.

In addition, regarding the form of residual stress, cold-rolled lining plates have compressive residual stress on the surface, whereas hot-rolled lining plates with surface polishing have tensile residual stress, which increases the resistance to stress corrosion cracking. I can't deny the part.

Next, a plurality of front lining plates 3 will be attached to the sides and bottom of the structure, but for the corner parts, the front lining plates 3 that have been bent in advance at the factory are attached, and the back lining plates 6 are passed through the embedded metal fittings 4. Fix by temporary bonding. There is a drain pipe in the center of the bottom, which will be attached like a funnel. Regarding this attachment, the most important thing is to ensure that the surface lining plates 30 and the mutual weld lines 3a of the surface lining plates do not form a cruciform joint where bath welding defects are likely to occur.

For further understanding, the details of the construction process described above will be explained using partial detailed drawings.

FIG. 2a is a cross section taken along the line A-A in FIG. 1, showing the state immediately before the mutual welding of the front lining plates 3a.
FIG. 3 is a representative cross-sectional view of the lined container of the present invention, showing the relationship in which there is a mounting bracket 4 thereunder. Figure 3a is the first
The cross section B to B in the figure shows the state just before the surface lining plate mutual welding 3a as in the second arg5, and the surface lining plate 3
This figure shows that there is a joint part of the back lining plate 6 under the welding groove and the front lining plate 3, and the back lining plates 6 overlap each other. 4th a
The figure is a cross section taken along the line C-C in Figure 1, and shows the state of the bottom lining plates mutually welded 3a in the same way as Figure 2a and gaa, and there is no change from Figure 33 except that the top-bottom relationship has been rotated by 90°. FIG. 5a is a cross section taken along line 1)-D in FIG. 1, showing the upper end of the surface lining 3, and similarly to FIGS. 2a to 4a, it shows the state immediately before the interlayer liquid 3a between the surface lining plates.

With the above steps, the surface lining plate is ready for welding. Welding method 1-1t Although there is no need to be particularly limited, it is necessary to melt the six-sided lining plate 6 and metallurgically apply bath welding to the mounting bracket 4 during initial layer welding, making it a relatively difficult welding process. However, if the TIG bath welding method (tungsten inert gas welding method) in which the current is pulse-controlled is used, the welding speed is slow, but the amount of penetration can be easily controlled, making it possible to obtain reliable welding. In order to obtain a stable weld penetration, the plate thickness at the overlap part should be 1. Orgm is the limit considering the welding conditions of the TIG welding method.

Experimental results regarding this will be explained. FIG. 13 shows the experimental results, and the overlap part of the back lining plate 60 is
The relationship between the contact current when welding by IG welding method and the thickness of the outer second inning plate 6 into which the metallurgical Vc bath is applied is shown. The curve aFi in the figure shows the relationship between the average current IA and the thickness of the welded plate when the pulse welding current is controlled to the waveform shown in FIG. 14 using a pulse welding method. The curved line in the figure shows the above relationship when the welding current is not pulse-controlled.

According to this, the thickness of the welded plate is larger when using the pulse current control method described above, but the plate thickness is 1.0 m.
If the welding current exceeds m, even if the welding current is increased, the rate of increase in the plate thickness after melting is significantly reduced, and the current effect is reduced. On the other hand, the upper limit of the welding current capacity of commercially available and easily available practical TIG welding machines is 20 OA, and if it exceeds this, it becomes a special product and is difficult to obtain. Considering this, the limit thickness of the back lining plate 6 is 1. Becomes Own. After welding the first layer, a liquid penetrant test is conducted to ensure that there are no defects, and then a second layer is welded to obtain the final form. Then the second
Conduct liquid penetrant testing on the layers to confirm soundness.

Since the surface lining plates 3a are properly connected to each other, the layered lining plates 6 are also brought into airtight contact with each other, and both the surface and IIk lining plates 3 and 6 are attached to the mounting bracket 4 at once. It means that he was kept in an airtight bath. First layer welding The final form can be obtained only by first layer welding without performing multi-layer welding for final welding, but when welding the back lining plate 6, the welding conditions are different from normal, so reliability is improved. For this reason, it is desirable to have a multi-layered welding contact with a low probability of welding defects penetrating.

Figures 2a, 3 and 4a and 5a are partial cross-sections of various parts after welding of the surface lining plates 3a, as shown in figures 2b, 3b, 4b and 5b, respectively. Hikoru.

(Operation of the invention) In the above configuration, the surface lining plate 3 is damaged due to some reason, and the activated liquid in the lining container 1 (
(hereinafter referred to as "liquid") leaks.

The liquid enters the gap between the front lining plate 3 and the back lining plate 6, but since the polar lining plate 6 is airtight, it stays within the limit enclosed by the separation of the back lining plate 6, and the liquid enters the gap between the front lining plate 3 and back lining plate 6. Since it does not penetrate into the concrete wall 2 and the gap is extremely small, leakage can be kept to a minimum and the contaminated area will not be expanded. In addition, since it does not penetrate and the amount of leakage is extremely small, when repairing the surface lining plate 3, preliminary radioactive substance decontamination work is facilitated, and the amount of radiation to which workers are exposed can be kept low. Furthermore, since the amount of air sealed in the gap is extremely small, even if the temperature difference between the stored material and the concrete wall 2 reaches a temperature difference that causes water vapor condensation, the amount is so small that it is difficult to judge that it is a leak. If the amount of water is not enough, water that seeps in from the concrete wall 2 side may get mixed in and generate a false signal.

In particular, the surface lining plates are mutually welded 3a by KTIG welding.
Since the welding is performed by replacing the weld with argon gas, the gap is filled with pure, completely dry inert gas, and no condensation occurs even if the temperature difference is such that water vapor condensation occurs.

Note that the addition of the coplanar lining plate 6 lowers the thermal conductivity, so that higher temperature radioactive materials can be stored in storage 1. However, it often causes thermal damage to concrete.

Incidentally, if TIG calendar contact is adopted and argon gas is sealed in the gap, this effect (insulating effect) will be further improved since the thermal conductivity of argon gas is lower than that of air. Also,
Since the front lining plate 3 does not come into direct contact with concrete or carbon steel, corrosion from the back side of the front lining 3 can be prevented. Further, by filling the gap with a gas pressure slightly higher than the stored liquid pressure and constantly monitoring the pressure drop from a distance using AI, it is possible to actively detect damage during the period of use. This means that even if stress corrosion cracking failure occurs, which is a characteristic failure pattern of commonly used austenitic stainless steel lined containers, the initial discount failure is extremely small, so even if there is a leak, the defect will pass through. In matter (
Although it is expected that there may be cases where the solid content (in the liquid) causes a clogging phenomenon in a short time and cannot be detected, it is also possible to detect cracks and failures in the gas pressure enclosure at the early stage of 19.

On the other hand, with the construction method of the present invention, there are no restrictions on transportation due to the brosok construction method described above, and L-sized 21-lined containers can be safely constructed with light work, and surface lining plates and 3-sided linings can be constructed safely. Since Kei 6 does not serve as a substitute material for construction work, there is no risk of defects occurring.

In addition, even if there is a defect on the bottom of the lining of the concrete wall 2, it can be easily visually inspected and repaired before attaching the surface lining plate 6, so it is necessary to anticipate the defect in advance and thicken the surface lining plate 3. The construction time can be shortened by reducing the amount of water used, saving materials and reducing the amount of swamp contact.

Next, the details of leakage detection in the present invention will be explained in 6th to 8th sections.
This will be explained using figures. There are two main methods for detecting leaks in lined containers. The first method is a conventional method in which the leak detection area is divided in advance on the back of the lining plate, a leak detector is installed in each area, and the leaked liquid is introduced into the leak detector through piping. This method detects the presence, time and area of the leak. The second method improves the above method and detects extremely small leaks, and is explained in the present invention by filling the space between the fc surface lining 3 and the control surface lining 6 with a gas whose pressure is slightly higher than that of the stored VW body. Leakage is detected by monitoring the pressure drop, but it is better to install a pressure detector in each of the smallest areas in which leakage can be detected in principle, where the detection area is surrounded by the mutual welding of the surface lining plates 3a. Although it is possible to precisely detect areas, the number of detectors increases, making it impractical in terms of monitoring and cost.

Therefore, similar to the conventional detection method described above, a plurality of minimum areas in which leakage can be detected in principle are connected in advance with piping to form an enlarged leak detection area, and each enlarged area is It is practical to fill each area with gas and install a pressure detector. For this reason, in the present invention, the cross section h-h in FIG. The connecting pipe 7 fixed to the mounting bracket 4 via the flange 8 is ranked 7 and 8.
Embed K in advance so that the 0 surface is exposed on the wall surface, attach the back lining plate 6 as explained earlier,
A communication port 9 is opened using a simple tool such as metal cutting scissors at the position where the communication pipe is connected to the base lining plate 6, and the periphery of the opening is hermetically welded to the flange 8 by airtight welding 10 for the communication port. Thereafter, the surface lining plate 3 is attached as described above, and the lined container 1 is completed as described above.

As mentioned above, by airtightly connecting the minimum leakage detection area with the connecting tWI 7, liquid and gas can freely pass through the enlarged leakage detection area, and the leakage liquid can be trapped in the piping buried in the concrete wall 2. (- not shown) can lead to the leak detector, so the present leakage detection can be carried out using the basic method of the leakage detection methods based on the different principles of the first and second methods described above.

Furthermore, if the connecting pipe 7 is not embedded in the concrete body 2 in advance, the connecting fitting 11, which has a concave overall cross section as shown in FIG. The connection port 13 is connected to the surface lining plate 3 at the part where the concave flange of the connecting fitting 11 is concave, and the surface lining plate 1 is connected to the surface lining plate 3 through the mutual bath contact 3a.
By opening the pipes one by one, liquid and gas can freely pass through the expanded leak detection area in the same way as the connecting pipe 7.
Leakage detection can be performed using either of the leakage detection methods based on the first and second principles described above.

Note that FIG. 9 is a side view of FIG. 8 and shows the shape of the connecting fitting 11.

(Effects of the invention) If the lining plate is damaged and leaks, the leaked liquid is spread over a wide area, preventing condensation, allowing accurate and prompt detection of the leak, and repairing the damage quickly and safely. [2. It is highly reliable and will not be easily damaged or damaged.
In addition, a lined container capable of storing high-temperature stored materials can be provided. It also saves on materials and can be constructed safely and in a short period of time while keeping the number of welders' man-hours low. A method of constructing a lined container can be provided.

(Other Examples) Above, the lined container and its construction method according to the present invention have been explained using specific examples, but the invention is not limited to the specific examples described here. Of course, many changes and modifications may be made to the lined container used without departing from the spirit of the invention. For example, the A-A cross section in Figure 1 is
Examples can be considered as shown in the figure. FIG. 10 shows a system in which leakage detection is performed in a double manner. If the front lining plate 3 is damaged and leaks, it is possible to detect leakage from the gap between the front lining plate 3 and the back lining plate 6, and the back lining plate 6 is In case of damage, leakage can be detected from the leakage detection groove 16 made up of the backing plate 15 and backing metal 14 welded to the scattering metal fitting 19. In this case, the construction method can be exactly the same as that of the present invention except that the shape of the mounting bracket 4 is modified. [Related publication, JP-A-53-2591
6) FIG. 11 also performs leakage detection in a double manner, and if the back lining plate 6 is damaged, leakage can be detected from the concave @18 formed on the mounting bracket 17. [Related publication, JP-A-56-128545J Figure 12 shows the long lining plate 6
A container that can store high-temperature liquid because the reliability against leakage can be improved by multiplexing a, 5 b, and 6 c, and a heat insulating effect is produced on the back lining plates 6 a, 6 b, and 6 c. Can be adopted.

[Brief explanation of drawings]

Fig. 1 is a partially cutaway bird chart of a lined container showing an embodiment of the present invention, Fig. 2a, Fig. 3a, and Fig. 4a.
Figures and Figures 5a and 5a are A-A and B-B in Figure 1.
, C to C and D to D show the state of the welding groove immediately before welding the surface lining plate, and Figs. 2b, 3b, 4b and 5b respectively show A to A in Fig. 1,
B-B. A cross-sectional view along C5-C and D to D shows the welding situation after welding the surface lining plate. 6V and 7 are cross-sectional views taken along E-E and FF' in FIG. 9 is a side view of box 8 and a structural diagram showing the shape of the connecting fitting; FIGS. 10, 11, and 12 are other embodiments of FIG. 3b. FIG. 13 is a diagram showing the relationship between the bath welding current and the plate thickness, and a diagram showing the pulse state of the welding current and the welding current. 2... Concrete wall 3... Surface lining board 6
... Solitary lining plate 7 ... Connecting pipe (7317)
Agent: Patent attorney Noriyuki Chika (and 1 other person) Total: 5
0L River A Certain Shizuka Figure 6 Figure 71 Zo Figure 8 Figure 9/2 Figure 10 Figure 11 Figure 12 Figure 13 Figure 30 10O/Sθ 200 260 Jθ0 Shiyo Sen [
-E>Ba CA)? 7-:A Figure 14

Claims (1)

[Scope of Claims] (1) A concrete wall, a mounting bracket embedded in the concrete wall, a back lining plate lined with the trench fitting, and a back lining plate installed on the bottom lining plate. A front lining plate, a leak detection area defined by a bath tangent to the front lining plate and formed between the front lining plate and the back lining plate, and a leak detection device connected to the leak detection area via piping. A lined container comprising: 12) The lining container according to claim 1, wherein the back lining plate is a cold rolled stainless steel plate having a thickness of 1.0 mm or less. (3) The leakage detection device is connected to a connecting pipe that communicates a plurality of leakage detection devices.
ff1I11 The lined container according to item 1. After temporarily installing the 14i Ik surface lining plate with the mounting bracket,
A lining container characterized in that a front lining plate is disposed on the back lining plate, and then the back lining plate is welded at the same time as the front lining plate is attached to the metal fitting by mutually welding the front lining plates. Construction method.