JP7184601B2 - Temperature cycle test device and its method - Google Patents

Description

The present invention relates to a temperature cycle test apparatus and method capable of, for example, a cryogenic temperature (cold/heat) cycle test.

As a temperature cycle test device, there is a device disclosed in Patent Document 1 below. In this apparatus, an immersion tank containing a corrosive liquid is placed under an air tank, and a vertical shaft having a sample suspension arm at the upper end is provided in the center of the air tank. The vertical movement of the vertical shaft immerses the sample in the immersion tank, Or it is configured to be pulled up into an air tank. A hot air box is connected to the air tank, and hot air can be sent into the air tank. At the lower end of the sample suspending arm, a shielding plate that moves up and down by vertical movement of the vertical axis is provided, and when the sample is pulled up into the air chamber, it is possible to separate the two chambers.

By the way, parts in various fields such as automobiles and rockets are required to have durability and stable performance even in harsh environments. Therefore, an apparatus for cryogenic temperature cycle tests using liquid oxygen or liquid nitrogen has also been proposed.

However, there was no cryogenic temperature cycle test equipment using liquefied hydrogen.

As a test for testing resistance to hydrogen, there is a device for immersing a test specimen in liquefied hydrogen. Therefore, the temperature cycle test is not performed. When performing a temperature cycle test in an immersion container, after cooling the specimen by immersing it, supply hydrogen gas or helium gas for heating into the immersion container to evaporate the liquefied hydrogen and heat it. Although it is necessary, the liquefied hydrogen is vaporized each time it is heated, resulting in a large loss of liquefied hydrogen. Moreover, since low-temperature hydrogen gas is present around the specimen until the liquefied hydrogen evaporates during heating, the temperature is difficult to rise, and the test takes a long time.

In addition, since hydrogen is flammable and must be handled with care, liquefied hydrogen is used as a cooling medium for the apparatus of Patent Document 1, in which the vertical shaft that moves up and down must be supported through the immersion tank. can't. This is because it is not possible to seal between the vertical shaft and the immersion bath.

JP-A-61-155726

SUMMARY OF THE INVENTION The main object of the present invention is to reduce the loss of a cooling medium such as liquefied hydrogen, shorten the test time, and increase the number of tests.

Means for this purpose include a cooling chamber for storing a liquid cooling medium, a heating chamber provided above the cooling chamber in communication, and a partition for partitioning a communication passage between the cooling chamber and the heating chamber so as to be openable and closable. A mechanism is provided above the heating chamber, and a lifting shaft is vertically supported with a raised position when the lower end is positioned in the heating chamber. and the elevating shaft is provided with an elevating mechanism for reciprocating the specimen holder between a position in the cooling medium in the cooling chamber and the heating chamber. temperature cycle test equipment.

In this configuration, the specimen is attached to the specimen holder at the lower end of the elevating shaft and moved up and down between the cooling chamber located below and the heating chamber located above it. It is not necessary to evaporate the cooling medium for each heating. In addition, when heating the specimen, the partition mechanism partitions the communication passage between the cooling chamber and the heating chamber, so that the gas in the heating chamber flows into the cooling chamber, and conversely, the cold gas in the cooling chamber is prevented from flowing into the cooling chamber. Suppress the inflow into the heating room. Since the lifting shaft for lifting the specimen is supported above the heating chamber, it can be supported without a special sealing structure.

According to the present invention, a heating chamber is provided above the cooling chamber, and a vertical movement of an elevating shaft supported above the heating chamber allows repeated cooling and heating of the specimen, and a special seal is provided. Since no structure is required, it is possible to obtain a cryogenic temperature cycle test apparatus using a cooling medium such as liquefied hydrogen. Moreover, the specimen can be heated by raising the vertical axis, and there is no need to evaporate the cooling medium. can be eliminated. Moreover, the temperature of the heating chamber can be raised quickly, and the test time can be greatly shortened, and the number of tests can be increased.

The schematic block diagram of the test apparatus using liquefied hydrogen. Sectional drawing which shows the part by the side of the cooling chamber of a temperature cycle test part. Sectional drawing of a temperature cycle test part. Sectional drawing which shows the heating chamber of a temperature cycle test part. The perspective view of a spray means. The top view of a spray means. FIG. 2 is a flowchart showing a temperature cycle test method using liquefied hydrogen.

One mode for carrying out the present invention will be described below with reference to the drawings.

A test apparatus 11 is shown in FIG. This test apparatus 11 includes a long-term immersion test section 13 that verifies durability by cooling to the temperature of liquefied hydrogen, and a temperature cycle test section 15 that performs a cryogenic temperature cycle test as a "temperature cycle test apparatus" of the present invention. have. Liquid liquefied hydrogen LH ₂ is used as a cooling medium in the test device 11 .

First, the long-term immersion test section 13 will be briefly described, and then the temperature cycle test section 15 will be described.

The long-term immersion test section 13 is composed of an immersion container 31 as a cooling medium storage tank for storing liquefied hydrogen _LH2 . The immersion container 31 includes a container body 32 with an open upper end, and a lid 33 detachably attached to the opening of the container body 32 to close the container body 32. The container body 32 has a vacuum insulation layer 34. there is The lid 33 has a heat insulating material 35 fitted to the upper end of the container body 32 , and is provided with a liquefied hydrogen supply port 36 and a hydrogen gas discharge port 37 . A supply pipe 38 extends downward from the liquefied hydrogen supply port 36 , and the tip of the supply pipe 38 extends along the inner peripheral surface of the container body 32 . A baffle plate 39 is provided below the heat insulating material 35 of the lid 33 .

In addition, the lid 33 is provided with a liquid level gauge 40, and the liquid level gauge 40 measures a preset maximum limit amount of liquefied hydrogen _LH2 stored in the container body 32, that is, a liquid level maximum height 41. To detect.

The long-term immersion test section 13 is placed on a weighing scale 42 , and based on the measured value of the weighing scale 42 , the storage amount of the liquefied hydrogen LH ₂ inside is determined.

The container main body 32 has two vertically arranged pipes extending outward. The two pipes are the introduction pipe 43 provided in the liquid phase portion in which the liquefied hydrogen LH ₂ is stored in the container body 32 and the gas phase portion above the liquid level of the liquefied hydrogen LH ₂ in the container body 32. A connecting pipe 44 is provided. The connecting pipe 44 is provided above the liquid level maximum height 41 described above.

Next, the temperature cycle test section 15 will be explained. The outline of the temperature cycle test section 15 is as follows.

The temperature cycle test section 15 comprises a cooling chamber 51 storing liquefied hydrogen LH ₂ , a heating chamber 52 provided in communication above the cooling chamber 51 , and a communication passage 53 between the cooling chamber 51 and the heating chamber 52 . It has a partition mechanism 54 for partitioning so that it can be opened and closed, and is arranged in parallel with the immersion container 31 of the long-term immersion test section 13 via an introduction pipe 43 and a connecting pipe 44 .

The inlet pipe 43 and the connecting pipe 44 are connected to the cooling chamber 51 in the temperature cycle test section 15 . That is, the liquid phase portion of the cooling chamber 51 and the liquid phase portion of the immersion container 31 are connected by the introduction pipe 43 , and the vapor phase portion of the cooling chamber 51 and the vapor phase portion of the immersion container 31 are connected by the connecting pipe 44 .

Above the heating chamber 52, an elevating shaft 55 is vertically supported with its lower end placed in the heating chamber 52 at a raised position. A test piece holder 56 is formed to The length of the elevating shaft 55 is appropriately set in consideration of the stroke, etc., and the test piece holder 56 at the lower end is formed in a substantially disc shape, and is provided with an appropriate holding means capable of holding a test piece T having an appropriate shape. It is

Further, the specimen holder 56 incorporates a temperature sensor 57 for measuring the temperature of the held specimen T (see FIGS. 3 and 4).

The elevating shaft 55 is provided with an elevating mechanism 58 that reciprocates the specimen holder 56 between the position in the liquefied hydrogen _LH2 in the cooling chamber 51 and the heating chamber 52 (see FIGS. 3 and 4). . Both the elevating mechanism 58 and the partition mechanism 54 of the communication passage 53 are operated by compressed air.

Specifically, the cooling chamber 51 has a cylindrical shape with a bottom as shown in FIG. An introduction pipe 43 is connected to the lower end of the cooling chamber 51, and has a structure in which the liquefied hydrogen _LH2 in the immersion container 31 is naturally introduced (see FIG. 1). With such a structure, the liquid level of the liquefied hydrogen LH ₂ in the cooling chamber 51 is the same as the liquid level of the liquefied hydrogen LH ₂ in the immersion container 31 .

A connecting pipe 44 is connected to the upper portion of the cooling chamber 51 . The connection position of the connecting pipe 44 is above the maximum liquid level 60 which is the same as the maximum liquid level 41 of the immersion container 31 .

A safety valve 61 is provided at the upper end of the cooling chamber 51 to release the hydrogen gas _GH2 when the internal pressure rises abnormally.

Above the cooling chamber 51 is the above-described communication path 53, and the communication path 53 is provided with a partition valve 62 of a partition mechanism 54 so as to be movable back and forth. The gate valve 62 is provided so as to be able to reciprocate in the direction across the communicating passage 53, and is pneumatically operated as described above. That is, as shown in FIGS. 1 and 3, the partition mechanism 54 opens and closes (OPEN/CLOSE) the partition valve 62 by supplying and discharging compressed air. A gate valve can be suitably used for such a partition mechanism 54 .

A pneumatically operated actuator of the partition mechanism 54 is surrounded by a purge box 63 . As shown in FIG. 3, the purge box 63 is provided with a supply port 63a and a discharge port 63b for taking in and out the nonflammable gas from the supply source (not shown) provided at a remote position. For example, a non-flammable gas such as nitrogen is gradually supplied and discharged so that the interior of the purge box 63 is always filled with the non-flammable gas. This is because the sensor necessary for driving the actuator is energized.

As shown in FIGS. 3 and 4, the heating chamber 52 above the communication passage 53 has a box-like shape penetrating vertically, and is provided with an openable and closable door 64 on the side surface (see FIG. 4). . A housing 52a constituting the heating chamber 52 has a double-walled structure having a hollow layer 65. The housing 52a has a fluid inlet 66 and a fluid outlet as circulation means for circulating a heating fluid in the hollow layer 65. 67 is formed (see FIG. 3), and fluid inlet 66 and fluid outlet 67 are connected to a fluid supply source (not shown). The fluid used here can be appropriately selected, and for example, water or hot water can be used.

The heating chamber 52 is provided with a gas introduction path 68 and a gas discharge path 69 for supplying a heating gas to the specimen T attached to the specimen holder 56 (see FIG. 4). Specifically, a gas introduction path 68 and a gas discharge path 69 are formed in a door 64 that openably closes the side opening of the housing 52a. A local gas supply (not shown) is connected. As a gas supply source connected to the gas introduction path 68 and the gas discharge path 69, in addition to the above-described heating gas, there is also provided a nonflammable gas for replacement.

As the gas used for heating, hydrogen gas or helium gas having an appropriate temperature higher than the cooling temperature of liquefied hydrogen _LH2 is used. For example, hydrogen gas may be used when verifying resistance to hydrogen, and helium gas may be used when taking into account the ease of handling, including removal of the specimen T.

The gas for heating may be supplied by simply pouring it in, but a gas blowing means 71 is provided in the heating chamber 52 in order to raise the temperature more efficiently.

The gas blowing means 71 is connected to the gas introduction path 68 and is integrally provided on the inner surface of the door 64 as shown in FIG. Since the gas blowing means 71 is provided on the door 64, the gas blowing means 71 comes out of the heating chamber 52 when the door 64 is opened, and when the door 64 is closed, the gas blowing means 71 blows the specimen T. It is a surrounding structure.

FIG. 5 shows a perspective view of a schematic structure of the door 64. As shown in FIG. The gas blowing means 71 is composed of a trunk 72 connected to the gas introduction passage 68 and having a U-shape in plan view, and a plurality of cylindrical nozzles 73 arranged on the lower surface of the trunk 72 . Since the trunk 72 is U-shaped in plan view, it has a semicircular arc portion 72a and linear portions 72b extending straight from both sides of the arc portion 72a. The interval between the straight portions 72b is set larger than the sizes of the test piece holder 56 and the test piece T, and the space between the straight portions 72b serves as an entrance through which the test piece holder 56 or the test piece T moves relative to each other.

The trunk 72 has a rectangular vertical cross-sectional shape, and the thickness of the trunk 72 is larger than the diameter of the nozzle 73 . The nozzle 73 has a plurality of injection holes 73a arranged along the longitudinal direction in a part of the outer peripheral surface.

The arrangement of the nozzles 73 is such that they surround the specimen T in the horizontal direction, as shown in FIG. That is, the nozzles 73 are arranged on the circumference around the center point P of the arc portion 72a of the trunk 72 which is U-shaped in plan view. The direction of the injection port 73a of the nozzle 73, that is, the injection direction, is directed toward the center point P of the arc portion 72a, that is, toward the specimen T. As shown in FIG.

A handle 74 for opening and closing is provided on the outer surface of the door 64 . The door 64 is fixed to the opening of the housing 52a by appropriate closing means such as bolting. In the drawing, illustration of the closing means of the door 64 is omitted.

Above the heating chamber 52, the lifting mechanism 58 described above is provided. The elevating mechanism 58 is composed of two rail portions 75 erected along the elevating shaft 55 and a slider 76 running on these rail portions 75 . The slider 76 is held at the upper end of the elevating shaft 55 and extends vertically from the edge of a slider mounting plate 77 extending in a direction orthogonal to the elevating shaft 55 . As with the partition mechanism 54, the raising and lowering of the slider 76 is pneumatically actuated. That is, the elevating mechanism 58 has a structure in which the slider 76 moves up and down (UP/DOWN) by supplying and discharging compressed air.

The lift mechanism 58 is also provided with a purge box 78 as in the case of the partition mechanism 54 described above. That is, as shown in FIG. 4, the purge box 78 is provided with a supply port 78a and a discharge port 78b for taking in and out the nonflammable gas. A provided supply (not shown) is connected.

A bellows 81 is provided around the elevation shaft 55 of the elevation mechanism 58 to enclose electronic components such as sensors in the purge box 78 so that the gas in the heating chamber 52 does not affect them. Specifically, as shown in FIG. 4, an upper end plate portion 82 at the upper end of the bellows 81 is provided on the lower surface of the slider mounting plate 77, and the through hole 82a in the center of the upper end plate portion 82 is airtight. The elevating shaft 55 is inserted through it. The lower end plate portion 83 of the lower end of the bellows 81 is fixed to the upper end surface of the heating chamber 52 by closing the communicating portion with the heating chamber 52, and is airtight with respect to the through hole 83a of the lower end plate portion 83. The elevating shaft 55 is inserted through it.

In the test apparatus 11 configured as described above, a temperature cycle test is performed in the steps shown in FIG.

That is, a test body mounting step S1 in which the test body T is attached to the test body holder 56 at the lower end of the vertically supported elevating shaft 55 in the heating chamber 52, and a replacement step S2 in which the inside of the heating chamber 52 is replaced with a nonflammable gas. , an opening step S3 for opening the partition provided between the heating chamber 52 and the cooling chamber 51 below the heating chamber 52, and a test piece lowering step S4 for lowering the test piece T in the heating chamber 52 into the cooling chamber 51. a cooling step S5 for cooling the test piece T to a predetermined temperature in the liquefied hydrogen LH ₂ in the cooling chamber 51; a test piece raising step S6 for raising the test piece T in the cooling chamber 51 into the heating chamber 52; A closing step S7 of closing the partition, a gas supply step S8 of supplying gas for heating into the heating chamber 52, a temperature raising step S9 of raising the temperature of the specimen T to a predetermined temperature, opening the partition and gas After successively going through the recooling preparation step S10 for stopping the gas supply in the supply step S8, the steps from the specimen lowering step S4 to the recooling preparation step S10 were repeated multiple times, and then the heating step S9 was completed. After that, the temperature cycle test method includes a removal preparation step S11 for stopping the gas supply in the gas supply step S8, and a specimen removal step S12 for removing the specimen T from the specimen holder 56 in the heating chamber 52.

In the test piece mounting step S1, the door 64 of the heating chamber 52 is opened to expose the test piece holder 56 of the elevating shaft 55 at the elevated position, and the test piece T is mounted. In the example of FIGS. 3 and 4, the holding means provided in the test piece holder 56 is a short columnar holder 56a for fitting the cylindrical test piece T on its outer peripheral surface. The holder 56a is configured to be attachable to the lower surface of the test object holder 56 by screwing it into the test object holder 56, coupling with other members, or the like. The test piece T is mounted according to the mounting structure, such as directly bolted to the test piece holder 56 without such a holder 56a.

At this time, there is no combustible gas or toxic gas in the heating chamber 52, and the sluice valve 62 as the aforementioned sluice in the communication passage 53 is closed. There may or may not be liquefied hydrogen LH ₂ in the cooling chamber 51 .

In the replacement step S2, the atmosphere is replaced with a nonflammable gas such as an inert gas for safety. In this replacement step S2, the nonflammable gas is supplied from the gas introduction path 68 provided in the door 64 through the gas blowing means 71. As shown in FIG. Evacuation may be performed instead of the replacement operation with nonflammable gas.

After that, when the cooling chamber 51 does not store the liquefied hydrogen LH ₂ , a predetermined amount of the liquefied hydrogen LH ₂ is supplied from the liquefied hydrogen supply port 36 of the immersion container 31 .

In the subsequent opening step S3, the closed gate valve 62 is opened to prepare for cooling the specimen T. As shown in FIG.

In the test piece lowering step S4, the lifting mechanism 58 is driven to lower the lifting shaft 55, the test piece T is immersed in the liquefied hydrogen _LH2 , and the cooling step S5 is performed. Even if the liquefied hydrogen LH ₂ bumps when the specimen T is immersed, the cooling chamber 51 is provided with a connecting pipe 44 connected to the immersion container 31 above the maximum liquid surface height 60. Gas GH ₂ is vented to the immersion vessel 31 and is secured.

After it is determined that the test piece T has reached a predetermined cooling temperature based on the detection of the temperature sensor 57 provided in the test piece holder 56, the cooling step S5 is finished, and the lifting mechanism 58 is driven to move the lifting shaft 55. is shifted to the test body raising step S6 for raising the

The specimen T is accommodated in the heating chamber 52 by the specimen raising step S6.

In the subsequent closing step S7, the partition mechanism 54 is driven and the partition valve 62 closes the communication passage 53 to isolate the cooling chamber 51. As shown in FIG. As a result, the hydrogen gas GH ₂ obtained by vaporizing the liquefied hydrogen LH ₂ in the cooling chamber 51 is prevented from entering the heating chamber 52, and the gas in the heating chamber 52 enters the cooling chamber 51 to vaporize the liquefied hydrogen LH ₂ . prevent the promotion of

Thereafter, the process proceeds to gas supply step S8, in which gas for heating is supplied from the gas introduction path 68 of the door 64, and the gas that has acted on the specimen T is discharged from the gas discharge path 69. As this gas, normal temperature hydrogen gas GH ₂ or heated hydrogen gas GH ₂ is used. Alternatively, helium gas may be used.

A heating fluid such as water or hot water supplied from a fluid inlet 66 circulates in the housing 52a of the heating chamber 52, and the heating chamber 52 is heated. Due to this action and the isolation of the cooling chamber 51 by the gate valve 62 as described above, the specimen T can be heated smoothly.

Moreover, since the gas for heating taken in from the gas introduction path 68 is blown toward the specimen T by the gas blowing means 71, the temperature of the specimen T rises quickly.

After it is determined that the test piece T has reached the predetermined heating temperature based on the detection by the temperature sensor 57 provided in the test piece holder 56, the temperature raising step S9 is terminated, and the re-cooling preparation step S10 is performed. . That is, the partition mechanism 54 is driven to open the partition valve 62 and the introduction of gas from the gas introduction passage 68 is stopped.

Thereafter, each step from the above-described test piece lowering step S4 to the re-cooling preparation step S10 is repeated a required number of times.

After completing the required number of cooling steps S5, the test piece raising step S6, closing step S7, gas supply step S8, and temperature raising step S9 are carried out, and then the process proceeds to the extraction preparation step S11. That is, the supply of gas from the gas introduction passage 68 is stopped and the inside of the heating chamber 52 is replaced with nonflammable gas. If the gas used in the gas supply step S8 is a nonflammable gas, the replacement can be omitted.

Finally, the door 64 of the heating chamber 52 is opened and the specimen T is removed from the specimen holder 56 .

In this way, the test specimen T moves up and down between the cooling chamber 51 located below and the heating chamber 52 located above it to repeat cooling and heating. It is not necessary to evaporate ₂ each time it is warmed. Therefore, consumption of the liquefied hydrogen _LH2 can be greatly reduced, and waste of the liquefied hydrogen _LH2 can be eliminated.

The effect of reducing waste of the liquefied hydrogen LH ₂ is that the partition mechanism 54 partitions the communication passage 53 between the cooling chamber 51 and the heating chamber 52 when heating the test specimen T, thereby suppressing the vaporization of the liquefied hydrogen LH ₂ . also enhanced by

In addition, since the heating chamber 52 is separated from the cooling chamber 51, the cold hydrogen gas _GH2 in the cooling chamber 51 can be prevented from flowing into the heating chamber 52. FIG. Therefore, the heating of the heating chamber 52 using the fluid and the positive and effective heating by the gas blowing means 71 are combined, and the temperature of the specimen T can be raised quickly.

As a result, coupled with the fact that the evaporation of liquefied hydrogen _LH2 is not required to raise the temperature of the test piece T, it is possible to shorten the cycle of cooling and heating, which greatly increases the number of tests. It is possible.

In addition, when conducting a temperature cycle test by evaporating liquefied hydrogen when the temperature of the specimen is raised, when using about 20 kg of liquefied hydrogen, one cycle is from lowering the temperature of the specimen once to raising it. One cycle required 3 days. In other words, the test specimen is placed in the test container, liquefied hydrogen is supplied to the test container to cool the test specimen, and then the liquefied hydrogen in the test container is left to evaporate. It took about 3 days to complete. Moreover, the amount of liquefied hydrogen consumed is about 20 kg of the supplied amount.

On the other hand, when the temperature cycle test is performed using the test apparatus 11 described above, even when using the same amount of liquefied hydrogen of about 20 kg, the time required for one cycle is about 1 hour. The loss amount was 0.5 kg.

Thus, it can be seen that the time required for the temperature cycle test can be greatly shortened and the waste of liquefied hydrogen can be significantly reduced.

In addition, since the lift mechanism 58 and the partition mechanism 54 are operated by compressed air and not driven by a motor, hydrogen, which is a combustible gas, can be easily confined away from electrical equipment and electronic parts. Moreover, since the lifting mechanism 58 and the partition mechanism 54 are provided with the purge boxes 63 and 78, safety can be ensured. Therefore, even if a combustible liquid such as liquefied hydrogen is used as a cooling medium, a safety device can be obtained.

Moreover, the test apparatus 11 can perform a long-term immersion test using the long-term immersion test section 13 in addition to the temperature cycle test using the temperature cycle test section 15, which is highly convenient.

The above configuration is one mode for carrying out the present invention, and the present invention is not limited to the configuration described above, and other configurations can be adopted.

For example, instead of the long-term immersion test section 13, a liquefied hydrogen storage tank that simply stores the liquefied hydrogen _LH2 may be provided.

As the cooling medium for the test device 11 and the temperature cycle test device (temperature cycle test section 15), in addition to the aforementioned liquefied hydrogen _LH2 , an appropriate cooling medium such as liquefied nitrogen, liquefied helium, and liquefied natural gas can be used. The gas for heating is also set appropriately.

DESCRIPTION OF SYMBOLS 15... Temperature cycle test part 31... Immersion container 43... Introduction pipe 44... Connection pipe 51... Cooling chamber 52... Heating chamber 53... Connection path 54... Partition mechanism 55... Elevation shaft 56... Specimen holder 58... Elevation mechanism 63... Purge Box 65 Hollow layer 66 Fluid inlet 67 Fluid outlet 68 Gas introduction path 69 Gas discharge path 71 Gas blowing means 73 Nozzle 78 Purge box T Test body

Claims (10)

a cooling chamber that stores a liquid cooling medium;
a heating chamber provided in communication above the cooling chamber;
A partition mechanism for partitioning a communication passage between the cooling chamber and the heating chamber so that it can be opened and closed,
Above the heating chamber, an elevating shaft is vertically supported with a raised position when the lower end is positioned in the heating chamber, and a test piece is removably held at the lower end of the elevating shaft A body holder is formed and
The elevating shaft is provided with an elevating mechanism that reciprocates the test specimen holder between a position in the cooling medium in the cooling chamber and the inside of the heating chamber ,
The partition mechanism and the lifting mechanism are surrounded by a purge box into which a nonflammable gas is supplied.
Temperature cycle test equipment. the cooling medium is a flammable liquid,
2. A temperature cycle test apparatus according to claim 1, wherein said partition mechanism and said elevating mechanism are pneumatically operated. 3. The temperature cycle test apparatus according to claim 1, wherein the heating chamber is provided with a gas introduction path and a gas discharge path for supplying a heating gas to the specimen . A gas blowing means connected to the gas introduction path is provided in the heating chamber,
A plurality of nozzles are provided in the gas blowing means,
The arrangement of the nozzles is an arrangement surrounding the horizontal circumference of the specimen,
4. The temperature cycle test apparatus according to claim 3 , wherein the injection direction of said nozzle is directed toward said test object. A housing that constitutes the heating chamber is formed in a double-walled structure having a hollow layer,
5. The temperature cycle test apparatus according to any one of claims 1 to 4 , further comprising circulation means for circulating a heating fluid in the hollow layer. A liquefied hydrogen storage tank for storing liquefied hydrogen is installed in parallel with the cooling chamber,
The liquid phase portion of the cooling chamber and the liquid phase portion of the liquefied hydrogen storage tank are connected by an introduction pipe,
6. The temperature cycle test apparatus according to any one of claims 1 to 5 , wherein the gas phase portion of the cooling chamber and the gas phase portion of the liquefied hydrogen storage tank are connected by a connecting pipe. 7. The temperature cycle testing apparatus according to claim 6 , wherein said liquefied hydrogen storage tank is an immersion vessel in which said specimen is immersed for testing. a test piece mounting step of mounting the test piece in the heating chamber on the test piece holder at the lower end of the vertically supported elevating shaft;
an opening step of opening a partition provided between the heating chamber and a cooling chamber below the heating chamber;
a test object lowering step of lowering the test object in the heating chamber into the cooling chamber;
a cooling step of cooling the specimen to a predetermined temperature in a liquid cooling medium in the cooling chamber;
a specimen raising step of raising the specimen in the cooling chamber into the heating chamber;
a closing step closing the partition;
a gas supply step of supplying a gas for heating into the heating chamber;
a temperature raising step of raising the temperature of the specimen to a predetermined temperature;
After sequentially passing through the recooling preparation step of opening the partition and stopping the gas supply in the gas supply step, the steps from the test body lowering step to the recooling preparation step are repeated a plurality of times, and then the above After completing the heating process,
a removal preparation step of stopping the gas supply in the gas supply step;
a test body removing step of removing the test body from the test body holder in the heating chamber ;
introducing the cooling medium in the cooling chamber through an introduction pipe connected to a liquid phase portion of a cooling medium storage tank arranged side by side in the cooling chamber;
The vaporized gas in the cooling chamber is released to the gas phase portion of the cooling medium storage tank.
Temperature cycle test method. The temperature cycle test method according to claim 8 , wherein the cooling medium is a flammable liquid. The cooling medium is liquefied hydrogen,
The temperature cycle test method according to claim 8 , wherein hydrogen gas is supplied in the gas supply step.

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