JPH0123726B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a clad sampler for collecting precipitated substances in a tank or other container.

In general, the work of regularly sampling substances precipitated in containers such as tanks, or crud, is used to determine the corrosion status of the piping system that transfers the liquid filled into the tank based on the amount of crud sampled. It is extremely important because it can be done.

Today, in nuclear power plants, etc., when the main condenser becomes unusable, a core isolation system is installed to remove the decay heat of the core after the reactor operation is stopped. The sublet chamber, which is constructed as part of the furnace, is filled with a predetermined amount of cooling water, and the steam generated in the furnace is introduced through a relief valve, and if the water level drops, the steam is released as appropriate. A system is adopted in which the water in the condensate storage tank is replenished by a pump partially driven by a steam turbine. However, since dangerous fluids containing radioactive materials enter and exit the sublet chamber used in this way, in order to ensure maintenance of the piping system communicating with the chamber, it is necessary to It is required to periodically sample and analyze the crud deposited within the chamber. In this case, in order to improve the accuracy of analysis by collecting a small amount of crud inside the chamber, it is necessary to collect an appropriate amount of crud per unit area at the bottom of the chamber.

From this point of view, when a pump is used as a means for collecting crud deposited at the bottom of a container such as a tank, the various demands described above cannot be met.

Therefore, the present inventors have conducted various studies to obtain a crud sampler that can properly sample the crud deposited on the inner bottom of the container such as the tank described above in a predetermined amount per unit area. The upper and lower chambers are connected to each other by inserting a sample push-up tube through the center, and the bottom of the lower chamber is opened and the sample is placed on the tank bottom plate, etc. The lower chamber is provided with an air supply and discharge means, and the upper chamber is provided with an air supply and discharge means and a sample collection means. It has been found that it is possible to obtain a simple cladding sampler that allows cladding within a range to be introduced from the lower chamber to the upper chamber while being mixed in the liquid, and then smoothly collected into the required sample collection container.

SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide a crud sampler which has a simple structure and can appropriately and efficiently collect crud within a predetermined area.

In order to achieve the above object, in the present invention, a sampling chamber with an open bottom is defined by a partition plate into an upper chamber and a lower chamber, and a sample push-up tube is inserted through the partition plate to open the upper chamber. The chamber and the lower chamber are in communication with each other, and the lower chamber is provided with air supply and discharge means, and the upper chamber is provided with air supply and discharge means and sample collection means.

In the above-mentioned clad sampler, it is preferable that a skirt is provided at the bottom opening of the lower chamber so as to be placed and fixed on the tank bottom plate. Further, the air supply means provided to the lower chamber can be comprised of an air distributor communicating with the air supply pipe and a plurality of air discharge pipes led out from the air distributor. In this case, it is preferable to provide a check valve for mixing air in a part of the air distributor so as to communicate directly with the lower chamber.

On the other hand, it is preferable that the diaphragm is provided with air supply and exhaust means for the lower chamber and sample collection means for the upper chamber. Note that it is preferable to provide a check valve at the end of the sample push-up tube that opens into the upper chamber.

Next, embodiments of the clad sampler according to the present invention will be described in detail below with reference to the accompanying drawings.

FIG. 1 is an explanatory diagram showing the principle structure of a clad sampler according to the present invention. That is, in FIG. 1, reference numeral 10 indicates a sampling chamber, and this chamber 10 has a diaphragm 12 approximately in its middle portion.
The chamber is divided into two upper and lower chambers via the upper and lower chambers, forming an upper chamber 14 and a lower chamber 16, respectively. The lower chamber 16 is completely open at its lower end and has a skirt 18 made of a flexible material at the edge of the opening.
will be extended. On the other hand, a sample push-up tube 20 is inserted through the center of the partition plate 12, and the upper chamber 14
and the lower chamber 16, and the lower end of the sample push-up tube 20 is positioned approximately in the middle of the skirt 18, and the upper end faces upward into the upper chamber 14. Note that a check valve 22 is provided at the open end of the upper end of the sample push-up tube 20 that communicates with the upper chamber 14 .

The upper chamber 14 is provided with an air supply/discharge port 24 at its top and a sample collection port 26 at one side of the bottom. Further, the lower chamber 16 is provided with an air supply port 28 and an air discharge port 30. However, an air supply pipe 32 is inserted into the air supply port 28 from the outside, and a plurality of air discharge pipes 36 are led out from a part of this air supply pipe 32 via an air distributor 34, so that each air discharge pipe 36 position the open end of the lower chamber 16 around the bottom skirt 18 .

Sampling chamber 10 configured in this way
On the other hand, the air supply pipe 32 is connected to an air supply source via an on-off valve _V1 , and an air conduit 38 is communicated with the air supply/discharge port 24 of the upper chamber 14, and this air conduit 38 is connected to an on-off valve _V2. is connected to the air supply source via. Further, a part of the air conduit 38 is opened to the atmosphere via an on-off valve V ₃ , and an air exhaust pipe 40 is communicated with the air outlet 30 of the lower chamber 16 so that the air exhaust pipe 40 is opened to the atmosphere via an on-off valve V _{4 .}
Open to atmosphere through. Furthermore, a sample collection tube 4 is connected to the sample collection port 26 of the upper chamber 14.
2 and is connected to an appropriate sample collection container (not shown) via an on-off valve _V5 .

Next, the operation of the clad sampler according to the present invention configured as described above will be explained.

First, the sampling chamber 10, which is connected to the piping as described above, is initially placed into the tank with all on-off valves closed, and the on-off valve _V4 is opened to exhaust the inside of the lower chamber 16. It is placed on the bottom plate 44. At this time, the sampling chamber 10 is fixed in position on the tank bottom plate 44 by the skirt 18 provided at its bottom.

Next, the on-off valve V ₂ is opened, air at a pressure of 1 to 2 kg/cm ² is supplied into the upper chamber 14 through the air conduit 38, and the on-off valve V ₂ is closed. At this time, the check valve 22 of the sample push-up tube 20 is closed by the pressure within the upper chamber 14. Thereafter, the on-off valves V ₁ and V ₄ are opened and air at a predetermined pressure is released into the lower chamber 16 through the air supply pipe 32 , air distributor 34 and air discharge pipe 36 , and the air is surrounded by the skirt 18 . The crud deposited on the tank bottom plate 44 floats due to the aeration effect and mixes with the liquid in the lower chamber 16. During this time, gas generated within the lower chamber 16 is discharged to the atmosphere via the air exhaust pipe 40.

In this state, if the on-off valve V ₄ is closed and the on-off valve V ₃ is opened, the pressure in the upper chamber 14 will decrease and at the same time the pressure in the lower chamber 16 will increase, so that the liquid in the lower chamber 16 will flow together with the cladding. The sample is introduced into the upper chamber 14 via the sample lift tube 20 .

After the liquid in the lower chamber 16 is transferred into the upper chamber 14 in this way, the on-off valves V ₁ and V ₃ are closed, the on-off valve V ₅ is opened, and the on-off valve V ₂ is opened again.
is released and a pressure of 1 to 2 kg/
By supplying ² cm 2 of air, the clad mixture in the upper chamber 14 can be collected into a predetermined sample collection container via the sample collection tube 42.

As is clear from the foregoing, according to the crud sampler of the present invention, crud within a predetermined area range can be properly and easily sampled by the sampling chamber 10 placed and fixed on the tank bottom plate 44. can. In addition, the timing of supplying and discharging air to the upper chamber 14 and lower chamber 16 mentioned above is easily achieved by configuring each on-off valve V ₁ to V ₅ with automatic valves and controlling the sequence using a timer etc. can do.

FIGS. 2 and 3 are cross-sectional views showing one embodiment of a sampling chamber constituting a clad sampler according to the present invention based on the above-described principle.
For convenience of explanation, the same reference numerals are given to the same constituent parts as those shown in FIG. 1, and detailed explanation thereof will be omitted.

That is, in this embodiment, the lower chamber 16 is attached to the partition plate 12 that defines the upper chamber 14 and the lower chamber 16 of the sampling chamber 10.
Air supply port 28 and air discharge port 30 communicating with
In addition, a sample collection port 26 communicating with the upper chamber 14 is provided. With this configuration, the connections between each opening and the conduit can be formed in advance on the partition plate 12 at once, and the partition plate 12 can easily connect the upper chamber 14 and the lower chamber 16 by flange connection. Since it can be assembled, it has the advantage of being extremely easy to manufacture and maintain. Further, by providing a check valve 46 on one side of the air distributor 34 and configuring the air distributor 34 and the lower chamber 16 to communicate directly, a predetermined pressure can be supplied from the air supply pipe 32 to the air distributor 34. When air is supplied, the liquid in the lower chamber 16 is introduced into the air distributor 34 from the check valve 46, so that the gas-liquid mixture is discharged from the air discharge pipe 36 to the tank bottom plate. As a result,
The action of mixing and stirring the crud deposited on the tank bottom plate with the liquid is more effective than using air alone.

Although preferred embodiments of the present invention have been described above, the present invention is not limited to the above-described embodiments, and it goes without saying that various design changes can be made without departing from the spirit of the present invention. .

[Brief explanation of drawings]

FIG. 1 is a cross-sectional explanatory diagram showing the principle configuration of a clad sampler according to the present invention, FIG. 2 is a sectional view of essential parts showing an embodiment of a sampling chamber of a clad sampler according to the present invention, and FIG. FIG. 3 is a bottom view of the sampling chamber shown in FIG. 10... Sampling chamber, 12... Diaphragm, 14... Upper chamber, 16... Lower chamber, 18... Skirt, 20... Sample push-up tube, 22... Check valve, 24... Air supply/discharge mouth,
26...Sample collection port, 28...Air supply port,
30...Air discharge port, 32...Air supply pipe, 34
...Air distributor, 36...Air discharge pipe, 38...
Air conduit, 40... Air discharge pipe, 42... Sample collection tube, 44... Tank bottom plate, 46... Check valve.

Claims (1)

[Claims] 1. A sampling chamber with an open bottom is defined by a partition plate into an upper chamber and a lower chamber, and a sample push-up tube is inserted through the partition plate to separate the upper chamber and the lower chamber. 1. A clad sampler, which communicates with each other, and is provided with air supply and discharge means for the lower chamber, and air supply and discharge means and sample collection means for the upper chamber. 2. The clad sampler according to claim 1, wherein a skirt is provided at the bottom opening of the lower chamber. 3. In the clad sampler according to claim 1 or 2, the air supply means provided to the lower chamber includes an air distributor communicating with the air supply pipe and a plurality of air discharged from the air distributor. A clad sampler consisting of a discharge pipe. 4. The clad sampler according to claim 1, wherein a check valve is provided at the end of the sample push-up tube that opens into the upper chamber. 5. The clad sampler according to claim 3, wherein a check valve is provided in a part of the air distributor so as to communicate directly with the lower chamber. 6. A clad sampler according to any one of claims 1 to 5, wherein the diaphragm is provided with air supply and exhaust means for the lower chamber and sample collection means for the upper chamber.