JPH03181763A - Heat insulating device of cryogenic equipment - Google Patents

Abstract

PURPOSE:To provide a heat insulating device for a cryogenic equipment which has a substantial effect of explosion-proof and can be used stably for a long period of time by a method wherein a storing container placed in cryogenic environment and storing cryogenic equipment and a circulation pipe for supplying and circulating inert gas within the storing container are provided and the circulation pipe is provided with a heater for use in heating the inert gas. CONSTITUTION:Equipment 2 such as a camera or the like is stored in a storing container 1 and then the storing container 1 is immersed in cryogenic liquid 3. In concurrent with this operation, a pump 11 and a heater 13 are operated inert gas is fed into a circulation pipe 10 and then heated by the heater 13. It is sufficient that a heating temperature is set to such a temperature as one the equipment 2 such as a camera or the like may perform its function. In order to keep a temperature of the camera at a value higher than -20 deg.C, it is necessary to heat the inert gas more than 100 deg.C. Inert gas heated more than 100 deg.C is supplied from a supplying port 8 into the storing container 1, the inert gas is circulated in the storing container 1 and then discharged into the circulation pipe 10 through a discharge port 9. The inert gas is transported subsequently in the circulation pipe 10, heated by the heater 13 and again supplied into the storing container 1.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a heat insulating device for cryogenic equipment such as a camera used in a cryogenic atmosphere in the field of LNG density meter, etc. , which has improved durability.

[Prior Art] Generally, devices such as cameras cannot perform their functions satisfactorily in an extremely low temperature atmosphere of about -20° C. or lower due to dew condensation or the like. Therefore, in the field of LNG density meters and the like, when these devices are used in an extremely low temperature atmosphere, it is necessary to keep them at a certain temperature.

Conventionally, insulating devices for keeping these devices warm have been used.
Finally, there is a device that includes a storage container that houses the equipment and is placed in an extremely low temperature atmosphere, and a heater wire that is arranged along the inner wall of the storage container.

This heat-retaining device heats and insulates the equipment in the storage container to a temperature of at least -20°C by energizing the heater wire 67j while the storage container is immersed in a cryogenic liquid such as LPG. I made it work in the state it was in and used it.

[Problems to be Solved by the Invention] However, in the above-mentioned heat retention device, a heater wire is used as a means to heat the inside of the storage container, so if a flammable material is used as the cryogenic limb, , ignition,
There were two major problems: safety due to dangers such as explosions. There was also the problem that the heater wire deteriorated and the heat insulating material deteriorated to a large extent due to the heat of the heater wire. As a result, the heater wire and the heat insulating material peel off and fall into the storage container, causing failure of the cryogenic equipment and deterioration of image quality, resulting in the inconvenience that it cannot be used for a long period of time.

Therefore, it is an object of the present invention to solve the above-mentioned problems and provide a heat insulating device for cryogenic equipment that has a large explosion-proof effect and can be stably used for a long period of time.

[Means for Solving the Problems] The present invention includes a storage container that is placed in a cryogenic atmosphere and stores cryogenic equipment, and a circulation pipe that supplies and circulates an inert gas into the storage container. The solution is that the circulation pipe is equipped with a heater that heats the inert gas.

[Function] In this way, since heated inert gas is used as the heating means, there is no danger of explosion. Furthermore, since the inert gas is constantly circulated during use, problems such as deterioration and peeling do not occur as with conventional heater wires, and durability is significantly improved.

Hereinafter, the present invention will be described in detail by showing examples and referring to the drawings.

[Example] FIG. 1 is an example of a heat retention device for cryogenic equipment of the present invention.

Reference numeral l in the figure is a storage container, which can be immersed in a cryogenic body (cryogenic atmosphere) 3 such as LNG while storing equipment (cryogenic equipment) 2 such as a camera.
Airtightness is maintained. Further, this storage container 1 is covered with a heat insulating material 4 such as polyurethane foam, except for a part of its outer periphery. A transparent window 5 is formed by fitting pressure-resistant glass or the like into the portion not covered with the heat insulating material 4, and this transparent window 5 is visible from the lens 2a of the camera 2.
through the outside of the storage container 1 (here cryogenic liquid 3)
can now be seen.

Further, an insulated umbilical tube 7 is connected to one side of the storage container 1, for storing a camera cable 6, etc., and for suspending the storage container 1. Also, on this side, there is a supply port 8 for supplying inert gas.
and an exhaust port 9 for discharging inert gas.

These supply ports 8 and discharge ports 9 are each connected to a circulation pipe 10 that connects them to each other and circulates inert gas. It is essential that the inert gas has a lower liquefaction temperature than the cryogenic liquid 3 used. The circulation pipe 10 is provided with a pump 11, and the pump II can feed inert gas into the circulation pipe 10 from a tank 12 for storing inert gas. Further, a heater 13 is provided on the downstream side of the circulation pipe IO from the pump 11, that is, near the supply port 8 of the storage container 1. This heater 13 is for heating the inert gas sent from the pump 11 and conveyed in the circulation pipe 10, and is usually capable of heating the inert gas to a temperature of about 1000 °C. Further, the outer peripheral surface of this circulation pipe IO is covered with a heat insulating material 14.

When using such a heat insulating device in a cryogenic atmosphere, first store the equipment 2 such as a camera in the storage container 1, and then place the storage container 1 in the desired cryogenic atmosphere, for example L
Immerse in cryogenic liquid 3 such as NG. At the same time, the pump 11 and the heater 13 are operated, and the circulation pipe 10 is
An inert gas is sent into the heater 1.
Heat at 3. When the cryogenic liquid 3 is LNG, nitrogen, argon, helium gas, etc. are used as the inert gas here since the temperature of the cryogenic liquid 3 is 11,615°C. The heating salinity may be set to a level that allows the equipment 2 such as a camera to function even in the atmosphere of the cryogenic limb 3, and normally in order to maintain the temperature of the camera at -20°C or higher, Although it is necessary to heat the inert gas to 100° C. or higher, this may be adjusted as appropriate depending on the temperature of the cryogenic liquid 3 used. The inert gas thus heated to 100° C. or higher is supplied into the storage container 1 from the supply port 8, circulated within the storage container 1, and discharged from the discharge port 9 into the circulation pipe IO. This inert gas is continuously conveyed through the circulation pipe 10 and heated by the heater 13,
It is supplied into the storage container 1 again.

In this way, in the heat retention device for this cryogenic equipment,
A storage container for heated inert gas! Since the device 2 such as a camera is kept at a constant temperature and condensation is prevented, the device 2 such as a camera can fully perform its original functions. This makes it suitable for use in fields such as LNG density meters.

1-Effects of the Invention] As explained above, the heat insulation device for cryogenic equipment of the present invention includes a storage container that is placed in a cryogenic atmosphere and stores the cryogenic equipment, and an inert gas inside the storage container. It has a circulation pipe that supplies and circulates the inert gas, and the circulation pipe is equipped with a heater that heats the inert gas, so it not only provides sufficient heat retention and dew condensation prevention effects, but also prevents explosions. There is no danger of Furthermore, it does not cause deterioration of the cryogenic equipment or heat retention equipment used, provides high reliability and high image quality, and significantly improves durability.

[Brief explanation of drawings]

FIG. 1 is a schematic sectional view showing an example of a heat retention device for cryogenic equipment of the present invention. 1...Storage container, 2...Camera etc. (cryogenic equipment), 3...Cryogenic body (cryogenic atmosphere), IO...Circulation pipe, I3... Heater.

Claims (1)

[Claims] It has a storage container that is placed in a cryogenic atmosphere and stores cryogenic equipment, and a circulation pipe that supplies and circulates an inert gas into the storage container, and the circulation pipe has a heating inert gas. A heat retention device for cryogenic equipment, characterized by being equipped with a heater.