JPH11295209A - Testing apparatus for ant nest-shaped corrosion - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a testing apparatus, for an ant nest-shaped corrosion, by which the propagation speed of the temperature change of a cooling and heating medium, to which the heat exchanger tube of a heat exchanger is subjected in the operation of an actual machine, can be reproduced faithfully and which can measure the time elapsed until a through hole is opened in a metal tube to be tested. SOLUTION: An ant nest-shaped corrosion environment exposure tank 1 whose inside is set at a gas-phase environment used to generate and grow an ant nest-shaped corrosion is provided. A thermostat 2 by which the temperature at the inside of the ant nest-shaped corrosion environment exposure tank 1 is kept at a prescribed temperature is provided. A cooling and heating medium passage 4 which is formed in such a way that a part of at least a side face is faced with the inside of the ant nest-shaped environment exposure tank 1 is provided. A cooling and heating source device 6 in which a temperature-controlled cooling and heating medium is circulated to the cooling and heating medium passage 4 is provided. A metal pipe 3, to be tested, which is installed as a part of the cooling and heating medium passage 4 and which has a face exposed inside the ant nest-shaped environment exposure tank 1 is provided. Then, the cooling and heating medium is made to flow to the inside of the metal pipe 3, to be tested, from the cooling and heating medium loop pipe 4. Thereby, a temperature change due to the propagation of the cooling and heating medium from the same inside as an actual machine can be given to the metal pipe 3 to be tested.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION The present invention relates to an operating condition (temperature cycle) of an actual machine for verifying a countermeasure for preventing ant nest corrosion generated in a heat exchanger tube of a heat exchanger such as an air conditioner, a refrigerator, and a cooler. The temperature change of the heat transfer tube generated in the heat transfer and the repeated occurrence of dew on the surface of the heat transfer tube and the repetition of wet and dry due to drying are faithfully reproduced, and the growth rate of the dust nest is quantitatively measured. It relates to a corrosion test device.

[0002]

2. Description of the Related Art A conventional test for corrosion of a tube was made in 1990 by a subcommittee for corrosion research of the Japan Copper Center by the Committee for Research on Corrosion of a Copper Tube. The provision of the temperature change to the metal tube under test as reported in (II) was a test only from the environment side. That is, a glass sealed bottle containing an aqueous solution in which an organic acid that causes ant nest-like corrosion is dissolved and a metal tube to be tested placed in a glass test tube so as not to directly touch the aqueous solution is heated at a constant temperature to which a temperature cycle is applied. This was a test method in which the temperature cycle was set in a bath, and the temperature cycle in the constant temperature bath propagated into the glass sealed bottle to generate a temperature cycle on the environment side. In addition, since the test was performed in a closed bottle, the oxygen in the closed bottle was reduced due to the progress of corrosion with time.

[0003] On the other hand, a corrosion test method in a corrosive gas atmosphere in which a test piece is repeatedly subjected to wet and dry conditions is disclosed in, for example, Japanese Patent Application Laid-Open No.
There is a method described in Japanese Patent Application Laid-Open No. 337241/1992, but in this method, the test piece enters and exits between a drying chamber and a reservoir in a corrosive gas atmosphere, and the wet and dry operations are repeated.

A method of measuring a corrosion rate using a phenomenon that a through hole is opened by corrosion is disclosed in Japanese Patent Application Laid-Open No. 51-148484.
There is a through-hole detecting means described in Japanese Patent Application Laid-Open No. H10-260, but in this method, a thickness of a part of a metal pipe to be tested is reduced in advance by thinning, and a leak detecting device is attached to the part.

[0005]

The temperature change applied to the heat transfer tubes of the heat exchanger in the actual machine is caused by the temperature change propagating from the inside of the heat transfer tube to the outside, which is acted on by the cooling medium flowing through the inside of the heat transfer tube, and the device being stopped. This is a temperature change that occurs due to temperature propagation from the external environment of the heat transfer tube. However, with the conventional test apparatus, it was not possible to reproduce the temperature propagation from inside the metal tube under test.

[0006] In addition, although the fin-like corrosion grows by a reduction reaction of oxygen, in the prior art, the oxygen concentration in the closed bottle decreases as the fin-like corrosion grows. This decrease in oxygen concentration slows down the growth rate of ant-nest corrosion.
For this reason, when measuring the growth rate of nest-like corrosion in accordance with the actual machine, it is desirable that the oxygen concentration in the exposure tank for the nest-like corrosion environment is maintained at a predetermined concentration, but in the prior art this is not the case. could not.

[0007] Further, the repetition of dry and wet on the surface of the heat transfer tube of the actual machine is due to dew condensation and drying due to temperature change. Therefore, in providing the surface of the metal tube to be subjected to the repetition of wet and dry, the method of dipping in the reservoir and then pulling up and drying did not simulate the repetition of dry and wet in the actual machine.

In addition, it is impossible to predict which part of the metal tube under test causes the corrosion of the fins in the actual machine, and which part forms the through hole most quickly. Therefore,
It was meaningless to test in advance by setting one location as the measurement point of the through hole.

SUMMARY OF THE INVENTION The present invention has been made to solve such a problem, and can faithfully reproduce the propagation direction of a temperature change received by a heat transfer tube of a heat exchanger during operation of an actual machine.
It is an object of the present invention to obtain an ant nest-like corrosion test apparatus capable of measuring the time until a through hole is opened in a test piece.

[0010]

According to a first aspect of the present invention, there is provided an apparatus for testing an ant nest-like corrosion environment, wherein the inside of the apparatus is a vapor phase environ- ment for exposing and growing an ant nest like corrosion. A constant temperature bath that holds the fin-shaped corrosive environment exposure tank and maintains the temperature inside the fin-shaped corrosive environment exposure tank at a predetermined temperature, and a ring that penetrates the constant temperature bath and is formed in an annular shape, at least a part of the side surface A cooling medium passage provided in such a manner as to face the inside of the ant nest-like corrosive environment exposure tank, a cooling heat source device provided in the cooling medium passage, and circulating the temperature controlled cooling medium through the cooling medium passage; and a cooling medium. A test piece provided as a part of a passageway and having a surface exposed in an exposure tank for corrosive corrosive environment exposure.

In the test apparatus of the present invention, the cooling medium passage is provided so as to cross the exposure tank for corrosive environment exposure, and the test piece is formed in the cooling medium passage. It is a tubular test piece provided in the part which crosses a corrosive environment exposure tank.

According to the third aspect of the present invention, the tubular test piece is removable.

According to a fourth aspect of the present invention, the cooling medium passage is provided so as to be adjacent to the fin-shaped corrosive environment exposure tank. It is a plate-shaped test piece provided as a partition between the nest-like corrosive environment exposure tank, one surface of which is exposed to the cooling medium passage, and the other surface of which is exposed to the ant nest-like corrosive environment exposure tank.

According to a fifth aspect of the present invention, a plurality of test pieces are provided.

According to a sixth aspect of the present invention, the temperature inside the exposure tank for corrosive nest environment is different from the temperature of the cooling medium, and the cooling medium passage is provided in the cooling medium passage. An intermittent device for intermittently flowing in a predetermined cycle is provided.

According to a seventh aspect of the present invention, a pressure detector for detecting the pressure of the cooling medium is provided in the cooling medium passage.

According to the eighth aspect of the present invention, the cooling medium is colored.

In the test apparatus of the present invention, an oxygen replenishing apparatus is provided for replenishing oxygen to the exposure tank for exposure to a corrosive nest environment.

[0019]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiment 1 FIG. 1 is a cross-sectional view of a tester for corrosion test of the present invention. In FIG. 1, an exposure tank for exposure to an ant nest corrosion environment 1 is a box-shaped closed vessel, in which a dilute aqueous solution of an organic acid such as formic acid is stored at the bottom, and a vapor phase environment in which ant nest corrosion is generated and grown. Have been. And the ant nest-like corrosive environment exposure tank 1 is installed in a larger constant temperature bath 2. A tubular metal tube 3 to be tested, which is a test piece, is placed in the exposure tank 1 for corrosive corrosive environment. Both ends of the metal tube 3 to be tested are provided outside the tank for corrosive corrosive environment exposure 1 by a pair of connection joints 5 penetrating and fixed to both side surfaces of the tank for corrosive corrosive environment exposure 1, respectively. Connected to the two cooling medium loop pipes 4. On the other hand, the other end of each cooling / heating medium loop pipe 4 is connected to a cooling / heating source device 6. The metal tube 3 to be tested and the cooling / heating medium loop pipe 4 constitute an annular cooling / heating medium passage, and the cooling / heating medium is circulated by the cooling / heating source device 6 in the arrow direction in the drawing. The cooling medium is a cooling source device 6
At a predetermined temperature.

The temperature inside the tank 1 for exposure to a corrosive corrosive environment is kept constant by a constant temperature bath 2, while the metal tube 3 to be tested is kept constant by a cooling medium flowing inside. Then, for example, the temperature inside the tank 1 for corrosive corrosive environment exposure is set to 40 ° C., and the temperature of the metal
When the temperature is set to 0 ° C., dew condensation occurs on the surface of the metal tube 3 to be tested. If this state is maintained for a predetermined period, corrosion proceeds on the surface of the metal tube 3 to be tested.

In the corrosion test apparatus having the above-described configuration, a cooling medium is supplied from the cooling medium loop pipe 4 to the metal pipe 3 to be tested so that the metal pipe 3 to be tested has the same internal structure as the actual machine. Temperature change due to propagation from Further, since the metal tube 3 to be tested has both ends connected to the pair of connection joints 5, the metal tube 3 can be easily removed from the ant nest-like corrosive environment exposure tank 1 and the workability of the test is improved.

Embodiment 2 FIG. FIG. 2 is a cross-sectional view showing another example of a tester for corrosion test of the present invention. In FIG. 2, the solenoid valves 8a, 8
b is provided. A power source 7 with a timer is electrically connected to the solenoid valves 8a and 8b. Solenoid valves 8a, 8b
Is a three-way solenoid valve that switches the flow path when the power supply 7 is turned on and off.

When the power supply 7 is in the ON state, the solenoid valve 8a opens a flow passage communicating with the cold heat source device 6 → the solenoid valve 8a → the metal pipe 3 to be tested, and closes a flow passage from the solenoid valve 8a → the solenoid valve 8b. On the other hand, the solenoid valve 8b opens a flow path communicating with the metal pipe 3 to be tested → the solenoid valve 8b → the cooling / heating source device 6, and the solenoid valve 8b → the solenoid valve 8
Close the channel a. And when the power supply 7 is off,
The electromagnetic valve 8a closes the flow path communicating with the cold heat source device 6 → the electromagnetic valve 8a → the metal pipe 3 to be tested, and opens the flow path from the electromagnetic valve 8a → the electromagnetic valve 8b. On the other hand, the electromagnetic valve 8b closes the flow path communicating with the metal pipe 3 to be tested → the electromagnetic valve 8b → the cooling / heating device 6 and closes the flow path of the electromagnetic valve 8b → the electromagnetic valve 8a.

By using the power supply 7 with a timer as the power supply for the solenoid valves 8a and 8b, the on / off control of the power supply 7 by the timer can interrupt the flow of the cooling medium to the metal pipe under test. That is, when the power supply 7 is on, the cooling medium circulates as shown by the solid arrow in FIG. 2, and when it is off, the cooling medium circulates as shown by the broken arrow.
The solenoid valves 8a and 8b and the power supply 7 with a timer constitute an intermittent device for intermittently flowing the cooling medium through the cooling medium loop pipe 4 in a predetermined cycle.

In such a configuration, a temperature change on the surface of the metal tube 3 to be tested can be given by the same heat propagation method as that of the actual machine, and further, a temperature cycle and a dry / wet cycle can be given to the surface of the metal tube to be tested. That is, for example, the temperature inside the exposure tank
When the temperature of the cooling medium is circulated at 20 ° C. by the cooling and heating source device 6,
By controlling the opening and closing of the solenoid valves 8a and 8b every hour, the metal tube 3 to be tested is changed from 40 ° C. to 20 ° every 12 hours.
C and the temperature change from 20 ° C to 40 ° C is repeated. Then, the surface of the metal tube 3 to be tested has a temperature of 40 ° C. → 20
Dew condensation occurs when the temperature changes to ° C, and then gradually dry after a temperature change from 20 ° C to 40 ° C. Therefore, a cycle of dry and wet can be performed every 12 hours.

In the thus-constructed corrosion test apparatus, the flow of the cooling medium to the metal tube 3 to be tested is interrupted, so that the metal tube 3 to be tested has a predetermined temperature in the constant temperature bath 2. And the temperature inside the exposed tank 1
A temperature cycle with the temperature of the cooling medium can be provided. Then, by this temperature cycle, a dry / wet cycle of dew condensation and drying accompanying the temperature cycle can be generated on the exposed surface of the metal tube 3 to be tested. This dry and wet cycle
This is equivalent to the repetition of wet and dry due to condensation and drying that occurs on the surface of the heat transfer tube during operation of the actual machine.

Embodiment 3 FIG. 3 is a cross-sectional view showing another example of the test piece corrosion test apparatus of the present invention. In this embodiment, in order to measure the growth rate of the fin-like corrosion from the thickness of the metal tube 3 to be tested and the time until the through-hole due to the fin-like corrosion opens in the metal tube 3 to be tested, A digital pressure gauge 9 is provided as a detecting device for detecting leakage of the cooling medium.

In FIG. 3, a digital pressure gauge 9 as a pressure detecting device is connected to the cooling medium loop pipe 4. The digital pressure gauge 9 detects a decrease in pressure of the cooling medium in the cooling medium loop pipe 4 that occurs when a through hole is opened in the metal pipe 3 to be tested. The digital pressure gauge 9 is provided with a recorder 10 for recording a monitor signal from the digital pressure gauge 9. The digital pressure gauge 9 and the recorder 10 can measure the time until a through hole is opened in the metal tube 3 to be tested.

Further, cold water is used as the cold medium of the present embodiment, the cold heat source device 6 is a cold water circulation device, and the cold water is colored. Therefore, the location of the through-hole opened in the metal tube 3 to be tested is colored and the confirmation is easy. Then, even if a through hole is opened in any part of the tubular metal tube 3 to be tested, it can be immediately confirmed.

Further, an oxygen cylinder 11 is connected to the tank 1 for corrosive corrosive environment exposure of the present embodiment. Then, an ant nest-like corrosive environment exposure tank 1 and an oxygen cylinder 1
1, a pressure reducing valve 12 is provided. The oxygen cylinder 11 and the pressure reducing valve 12 constitute an oxygen replenishing device that compensates for the amount of oxygen in the tank for exposure to a corrosive corrosive environment that decreases with the progress of corrosion. As a result, the oxygen concentration in the tank for corrosive corrosive environment exposure is maintained at a predetermined concentration, the corrosion rate becomes constant, and a test for corrosive nest corrosion in accordance with an actual machine can be performed.

In the thus configured corrosion test apparatus, a detection device for detecting leakage of the cooling medium is provided as follows.
A digital pressure gauge 9 for detecting a pressure drop in the cooling medium loop pipe 4 is provided, and a recorder 10 for recording a monitor signal from the digital pressure gauge 9 is provided. The time until leakage can be measured, and the time until a through hole is opened in the metal tube 3 to be tested due to ant nest corrosion can be measured.

Further, since the cooling / heating medium is colored, it is possible to immediately confirm any portion of the metal tube 3 to be tested which has a through hole. Furthermore, since the oxygen cylinder 11 and the pressure reducing valve 12 are provided, the oxygen concentration in the exposure tank 1 for corrosive corrosive environment is maintained at a predetermined concentration, the corrosion rate becomes constant, and It can be a test for shape corrosion.

Incidentally, even if the recorder 10 is not provided, for example,
It is also possible for an experimenter to measure the time from the start of the test to the output of the detection signal of the digital pressure gauge 9.

Embodiment 4 FIG. 4 is a cross-sectional view of a main part showing another example of an ant nest-like corrosion test apparatus of the present invention. The ant nest-like corrosive environment exposure tank 21 of the present embodiment has an opening 21a in the upper part of FIG. The connection member 22 is attached to the opening 21a. At both ends of the connecting member 22,
Flanges 22a and 22b are formed over the entire circumference. The connecting member 22 is fixed by the fastener 17, for example, a bolt and a nut, with one flange portion 22 a facing the opening portion 21 a. The packing 16 is provided between the flange portion 22a and the tank 21 for exposure to a corrosive corrosive environment, and is sealed.

On the other hand, an opening 24a protruding downward in FIG.
A flange 24b is formed over the entire circumference at the tip of the protruding opening 24a. The flange portion 22b and the flange portion 24b are arranged so as to face each other, and a plate-shaped plate-shaped test piece 13 as a test piece is sandwiched between the two. The packing 16 is hermetically sealed between the flange portion 22b and the plate-shaped test piece 13 and between the flange portion 24b and the plate-shaped test piece 13. The flange portion 22b and the flange portion 24b are fastened by fasteners 17 penetrating both.

With this configuration, the plate-shaped test piece 13
Is provided as a partition between the cooling / heating medium loop pipe 24 and the fin-like corrosive environment exposure tank 21, one surface of which is exposed to the cooling / heat medium loop pipe 24, and the other side of which is exposed to the fin-like corrosive environment exposure tank 21. Has been exposed. Other configurations are the same as those of the third embodiment.

In the thus-constructed corrosion test apparatus, the test piece 13 is sandwiched between the exposure tank 21 and the cooling medium loop pipe 24 so as to serve as partitions. Therefore, in the same manner as the tubular metal tube to be tested, the plate-shaped test piece 13 is subjected to the temperature cycle and the dry / wet cycle by the supply of the cooling medium to the exposed surface.

Embodiment 5 FIG. 5 is a cross-sectional view of a main part showing another example of a tester for corrosion test of the present invention. The ant nest-shaped corrosive environment exposure tank 31 of the present embodiment has an opening 31a in the upper part of FIG. Then, each opening 31a
, The same connecting member 22 as in the fourth embodiment is attached. At both ends of the connecting member 22, a flange portion 22a,
22b is formed over the entire circumference. Connecting member 22
Is fixed with the fastener 17 with the one side flange portion 22a facing the opening portion 31a. Flange part 22a
Packing 1 between the
6 are arranged and hermetically closed.

On the other hand, the cooling medium loop pipe 34 is
Are provided with a plurality of projecting members 32 projecting downward. The protruding member 32 is connected to a pair of three-way cocks 18 provided in the cooling medium loop pipe 34 by two connecting portions 32.
a are connected to each other. A flange 32b is formed at the tip of the protruding member 32 over the entire circumference. A bypass pipe 19 is provided between the pair of three-way cocks 18.
Are arranged. The three-way cock 18 can select whether the cooling medium loop pipe 34 communicates with the connection part 32 a or the bypass pipe 19.

The flange portion 22b and the flange portion 32b are disposed so as to face each other, and the plate-shaped test piece 13 is sandwiched between them. Flange part 2
The packing 16 seals between 2b and the plate-like test piece 13 and between the flange portion 32b and the plate-like test piece 13. The flange portion 22b and the flange portion 32b
It is fastened with a fastener 17 that penetrates the body. Other configurations are the same as those of the fourth embodiment.

In the present embodiment, a plurality of plate-shaped test pieces 13 are set in one test apparatus and can be evaluated simultaneously. Each of the plate-shaped test pieces 13 has, for example, a different material and a different plate thickness. Then, at the start of the test, each three-way cock 18 is communicated in the direction of the connecting portion 32a so that the cooling medium acts on each plate-shaped test piece 13. Then, when it is confirmed that a through hole is opened in any one of the plate-shaped test pieces 13 during the test, a pair of this portion is so set as to prevent the cooling medium from flowing into the tank 31 for exposing the ant-nest corrosive environment. The three-way cock 18 is switched to communicate with the bypass pipe 19. Then, the plate-shaped test piece 13 in which the through-hole is formed and the connecting member 22 are removed, and a lid (not shown) is attached instead.
The opening 31a is closed. Then, the other plate-shaped test pieces 13 are continuously tested.

In the thus-constructed corrosion test apparatus, a plurality of plate-like test pieces 13 are attached. For example, plate-like test pieces 13 having different materials and plate thicknesses are mounted under the same conditions. Can be tested at the same time. Further, even if a through-hole is formed in one plate-like test piece 13, another plate-like test piece 13 can be tested continuously.

[0043]

According to the present invention, there is provided an apparatus for testing an ant nest-like corrosion environment, wherein a tank for exposing an ant nest like a gaseous environment is provided in which a gas phase environment for generating and growing an ant nest like corrosion is provided. A constant temperature bath that houses the corrosive environment exposure bath and maintains the temperature inside the corrosive environment exposure bath at a predetermined temperature, and a circular bath that penetrates the constant temperature bath and has at least a part of the side Cooling medium passage provided so as to face the inside of the corrosive environment exposure tank, a cold heat source device provided in the cooling medium passage and circulating a cooling medium controlled in temperature through the cooling medium passage, and as part of the cooling medium passage And a test piece having a surface exposed in an exposure tank for corrosive corrosive environment exposure. Therefore, a temperature change similar to that of the actual device can be given to the test piece.

According to the second aspect of the present invention, the cooling medium passage is provided so as to traverse the tank for exposing the corrosion corrosive environment, and the test piece is provided in the cooling medium passage. It is a tubular test piece provided at a portion crossing a nest-like corrosive environment exposure tank. Then, since the cooling medium flows through the inside of the tubular test piece, the tubular test piece can be given a temperature change due to propagation from inside similar to the actual machine.

In the third embodiment of the present invention, the tubular test piece is removable. Therefore, the workability of the test is improved.

According to a fourth aspect of the present invention, the cooling medium passage is provided so as to be adjacent to the tank for exposing a corrosive corrosive environment, and the test piece is connected to the cooling medium passage and the antenna. It is a plate-shaped test piece provided as a partition between the nest-like corrosive environment exposure tank, one surface of which is exposed to the cooling medium passage, and the other surface of which is exposed to the ant nest-like corrosive environment exposure tank. A temperature change similar to that of the actual machine can be given to the tubular test piece.

In the test apparatus of the present invention, a plurality of test pieces are provided. Therefore, for example, test pieces having different materials and plate thicknesses can be tested simultaneously under the same conditions.

According to a sixth aspect of the present invention, the temperature of the cooling medium is different from the temperature of the inside of the exposure tank for exposing the corrosion medium and the temperature of the cooling medium. An intermittent device for intermittently flowing in a predetermined cycle is provided. Therefore, it is possible to cause the same wet / dry cycle of dew condensation and drying on the exposed surface of the test piece as in the actual machine accompanying the temperature cycle.

According to a seventh aspect of the present invention, a pressure detection device for detecting the pressure of the cooling medium is provided in the cooling medium passage. By detecting the pressure drop of the cooling medium, it is possible to detect that the through hole is opened in the test piece, and it is also possible to measure the opening time of the through hole in the test piece due to ant nest corrosion. .

[0050] In the test apparatus for corrosion test of the ant nest shape according to the eighth aspect, the cooling medium is colored. Therefore, the through hole formed in the test piece can be easily confirmed.

According to a ninth embodiment of the present invention, an oxygen replenishing apparatus for replenishing oxygen is provided in the exposure tank for exposure to a fin-like corrosive environment. Therefore, the concentration of oxygen in the tank for exposure to the ant nest corrosion environment is maintained at a predetermined concentration, the corrosion rate becomes constant, and the test for ant nest corrosion according to the actual machine can be performed.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view of an ant-nest corrosion test apparatus of the present invention.

FIG. 2 is a cross-sectional view showing another example of a test piece corrosion test apparatus of the present invention.

FIG. 3 is a cross-sectional view showing another example of a test specimen for corrosion test of the present invention.

FIG. 4 is a cross-sectional view of a main part showing another example of a tester for corrosion test of the present invention.

FIG. 5 is a cross-sectional view of a main part showing another example of an ant nest-like corrosion test apparatus of the present invention.

[Explanation of symbols]

1,21,31 Dust corrosive corrosive environment exposure tank, 2 constant temperature tank, 3 metal tube under test (test piece), 4 cooling medium loop piping (cooling medium passage), 6 cold heat source device, 7 power supply with timer ( Intermittent device), 8a, 8b solenoid valve (intermittent device), 9 digital pressure gauge (pressure detecting device), 11 oxygen cylinder (oxygen replenishing device), 12 pressure reducing valve (oxygen replenishing device), 13 plate-shaped test piece (device Test pieces).

Claims (9)

[Claims] 1. A tank for exposing a corrosive corrosive environment in which a vapor phase environment is formed for generating and growing corrosive corrosive corrosion, and a tank for exposing a corrosive corrosive environment, wherein the tank is exposed. A constant temperature bath for maintaining the temperature inside the corrosive environment exposure tank at a predetermined temperature; and a penetrating through the constant temperature bath and formed in an annular shape, at least a part of a side of which faces the inside of the corrugated corrosive environment exposure tank. A cooling medium passage provided in the cooling medium passage; a cooling / heating source device provided in the cooling medium passage for circulating a cooling medium whose temperature is controlled through the cooling medium passage; and a cooling medium passage provided as a part of the cooling medium passage. A test specimen having a surface to be exposed in a nest-like corrosive environment exposure tank. 2. The cooling medium passage is provided so as to traverse the exposure tank for corrosive environment, and the test piece traverses the exposure tank for corrosion in the cooling medium passage. 2. The test apparatus according to claim 1, wherein the apparatus is a tubular test piece provided at a portion to be tested. 3. The test apparatus according to claim 2, wherein the tubular test piece is detachable. 4. The cooling medium passage is provided so as to be adjacent to the aforesaid corrosive corrosive environment exposure tank, and the test piece is provided on the cooling medium passage and the acrosinoid corrosive environment exposure tank. A plate-shaped test piece having one surface exposed to the cooling medium passage and the other surface exposed to the fin-like corrosive environment exposure tank. The described ant nest corrosion test apparatus. 5. The test apparatus according to claim 4, wherein a plurality of the test pieces are provided. 6. A temperature inside the exposure tank for corrosive corrosive environment exposure and a temperature of the cooling medium are different from each other, and the cooling medium is intermittently connected to the cooling medium passage in a predetermined cycle. 6. An ant-nest corrosion test apparatus according to claim 1, further comprising an intermittent device for causing flow. 7. The corrosion test apparatus according to claim 1, wherein a pressure detecting device for detecting a pressure of the cooling medium is provided in the cooling medium passage. 8. The test apparatus according to claim 1, wherein the cooling medium is colored. 9. The test apparatus according to claim 1, further comprising an oxygen replenishing device for replenishing oxygen in the exposure tank for exposure to a fin-like corrosive environment.