JPH031075A - Condensation preventive structure for liquid nitrogen supply system - Google Patents

Abstract

PURPOSE:To intercept a pipeline from atmosphere and prevent condensation on the pipeline effectively by a method wherein dry N2 atmosphere, not containing moisture, is formed around the pipeline between a liquid nitrogen tank and a device. CONSTITUTION:A linear pipeline 3, connecting an automatic liquid nitrogen supplying device 2 to a manufacturing device 5, is provided with a dry N2 atmosphere forming device 6 at a place whereat condensation is supposed to take place. A shielding member or a sealed vessel 61, having the inlet port 62 and the outlet port 63 of dry N2, received low-temperature dry N2 supplied by a dry N2 supplying device and forms a dry N2 atmosphere around the pipe line 3. The pipeline 3 is intercepted perfectly from atmosphere by the dry N2 atmosphere of drying degree 100%, which is formed in the vessel 61, whereby condensation will never take place on the surface of the pipeline, whose tempera ture is cryogenic.

Description

[Detailed Description of the Invention] <Industrial Application Field> The present invention prevents condensation in a pipeline between a liquid nitrogen tank and the equipment in a liquid nitrogen supply system that supplies liquid nitrogen to equipment that requires cooling. The present invention relates to a structure, and particularly to a dew condensation prevention structure for a liquid nitrogen supply system that does not cause problems even when liquid nitrogen is continuously supplied.

<Prior art> In conventional liquid nitrogen supply systems, in order to prevent condensation that can cause short circuits in the electrical system, insulation materials are installed in areas where condensation is expected to simply keep things cool. Ta.

<Problems to be Solved by the Invention> However, the conventional method of preventing dew condensation by simple cold storage using a heat insulating material has the following problems.

15 Condensation occurs from the joints of the insulation material.

2. If liquid nitrogen is continuously supplied, cracks will form in the insulation material, and dew condensation will occur from the cracks.

;), it is not possible to install home insulation behind the equipment to be cooled, so condensation cannot be prevented in that area.

SUMMARY OF THE INVENTION Therefore, an object of the present invention is to provide a dew condensation prevention structure for a liquid nitrogen supply system that can solve all of the above problems.

<Means for Solving the Problems> Condensation on the surface of the Vibe line that supplies liquid nitrogen to the device occurs because the extremely low temperature of the Vibe line comes into direct contact with the moisture-containing atmosphere. In other words, if the surface of the Vibrine does not come into direct contact with the moisture-containing atmosphere, no condensation will occur. Therefore, prevention of condensation on pipelines should be possible by cutting off direct contact between extremely low-temperature pipelines and the atmosphere, without relying on insulation.

The present invention was made based on this idea, and its characteristics include dry N, which forms a dry N (nitrogen gas) atmosphere around the pipeline between the liquid nitrogen tank and the device.
By providing an atmosphere forming device, the pipeline is placed in a dry N2 atmosphere and the pipeline surface is shielded from the atmosphere.

It is preferable that the dry nitrogen atmosphere forming device is provided with a shielding member provided around the pipeline, and a dry nitrogen atmosphere is formed between the shielding member and the pipeline.

Further, it is preferable that the dry N atmosphere forming device is formed by a spraying device that sprays dry N toward the pipeline.

<Function> A dry N2 atmosphere that does not contain moisture is formed around the pipeline by the dry N2 atmosphere forming device, and this dry N2 atmosphere isolates the pipeline surface from the atmosphere and prevents dew condensation.

Furthermore, if the dry N2 atmosphere forming device is equipped with a shielding member, the dry N2 atmosphere itself is also shielded from the atmosphere, thereby preventing moisture from entering the dry N2 atmosphere and maintaining the dry state. Well held and dry N,
The amount of dry N supplied can be reduced.

In addition, when the above-mentioned dry N atmosphere forming device is formed by a spraying device, the dry N atmosphere can be formed anywhere, such as on the back side of the equipment to be cooled, where it was previously impossible to prevent dew condensation. Also, condensation is effectively prevented.

<Example> Hereinafter, the present invention will be explained in detail with reference to illustrated embodiments.

FIG. 1 is a block diagram of an embodiment of a liquid nitrogen supply system having a dew condensation prevention structure according to the present invention, where ■ is a liquid nitrogen tank, 2 is an automatic liquid nitrogen supply device, 3 is a pipeline, and 5 is a cooling In the manufacturing equipment to be manufactured, the straight pipeline 3 connecting the liquid nitrogen automatic supply equipment 2 and the manufacturing equipment 5 includes:
A dry N atmosphere forming device 6 is provided at a location where dew condensation is expected to occur.

FIG. 2 (aXb) is a front view and a side view of the dry N atmosphere forming device 6 shown in FIG. 1. In the same figure,
Reference numeral 61 denotes a closed container as a shielding member having an inlet 62 and an outlet 63 for dry N, and this container 6I is supplied with low-temperature dry N fed from the above-mentioned population 62 by a dry N supply device (not shown).

The dry N atmosphere is formed around the pipeline 3 by accommodating the dry N atmosphere, and it also serves to shield this dry N atmosphere from the atmosphere. The dry N fed into the container 61 is constantly discharged from the outlet 62, so that 100% dry N and atmosphere are maintained inside the container 61.

Therefore, according to the above configuration, the pipeline 3 is completely isolated from the atmosphere by the 100% dry N2 atmosphere formed in the container 61, so that dew condensation occurs on the surface of the extremely low temperature pipeline. do not have. Moreover, this dry N, the atmosphere is 6 containers! Since it is shielded from the atmosphere, there is no risk of water getting mixed in, which is popular. Moreover, since dry N is basically stored in the container 61,

Diffusion is prevented and dry N consumption is reduced. Furthermore, since low-temperature dry N is used, heat transfer to the liquid nitrogen in the vibrator 3 can be reduced.

Note that the dry Nt may be circulated by interposing a dehumidifying device (not shown) between the dry Nt supply device and the container 61.

FIGS. 3(a) and 3(b) show a modification of the dry N2 atmosphere forming device 6 shown in FIG. 2, and are a front view and a side view of the dry N2 atmosphere forming device when an L-shaped pipeline 3 is used. This is what is shown.

FIG. 4 shows an embodiment of a dry N2 atmosphere forming device suitable for preventing dew condensation on the back side of the device. It consists of a pair of dry N and spray pipes 65, 65 arranged above and below. A plurality of spray ports 66 are provided at the tip of the spray pipe 65 toward the pipeline 3. In this way, dry N, spray tube 65.
65 does not have a structure that surrounds the entire circumference of the pipeline 3, so it can be used on the back side of the equipment, etc., where conventional methods of preventing dew condensation using heat insulating materials could not be used, and dew condensation can be prevented there.

In the configuration shown in L, dry N (not shown), which is sent from the supply device to the spray pipe 65, is sprayed from the spray port 66 onto the pipeline 3 and the back side of the manufacturing device 5. However, in this case, unlike the embodiments shown in Figures 2 and 3, the dry N and atmosphere formed around the pipeline 3 are exposed to the atmosphere, so moisture from the atmosphere is likely to mix in. , always dry N around the pipeline.
2, it is necessary to provide sufficient ventilation.

In the above embodiment, a pair of blowing pipes 65 are arranged above and below the pipeline 3, but the number and position are not limited to these (although it goes without saying that they can be changed as appropriate).

Effect> As is clear from the above explanation, according to the present invention, a dry nitrogen atmosphere containing no moisture is formed around the babe line between the liquid nitrogen tank and the device, and this dry nitrogen, dry nitrogen,
Since the atmosphere blocks the pipeline from the atmosphere, moisture in the atmosphere does not come into direct contact with the pipeline, effectively preventing dew condensation on the pipeline. In addition, completely different from conventional methods, the structure prevents dew condensation without using any insulation material, so it is possible to prevent condensation from condensation at the joints of the insulation material, cracks in the insulation material that occur when liquid nitrogen is continuously supplied, etc. This prevention structure has nothing to do with the problem. ), even if there are precision instruments, computers, or other electrical systems under the pipeline that are sensitive to water,
The liquid nitrogen supply system can be operated continuously with peace of mind. Furthermore, since inexpensive nitrogen is used, dew condensation can be prevented at low cost.

Note that if the dry N atmosphere forming device is equipped with a shielding member, the dry N atmosphere can be shielded from the atmosphere, thereby preventing moisture from entering the dry N atmosphere.
The dry state can be maintained well, and the amount of dry N consumed can be reduced.

In addition, when the dry N atmosphere forming device is formed by a spraying device, the dry N atmosphere can be easily formed even on the back side of the device, in narrow places, etc., where it was previously impossible to prevent dew condensation.

[Brief explanation of drawings]

Figure 1 is a block diagram of a liquid nitrogen supply system equipped with the dew condensation prevention structure of the present invention, and Figures 2 (a) and (b) are dry nitrogen
, a front view and a side view showing an embodiment of the atmosphere forming device, FIGS. 3(a) and 3(b) are a front view and a side view showing a modification of the embodiment shown in FIG. 2, and FIG. N. is a diagram showing an example of a pond of an atmosphere forming device. l...liquid nitrogen tank, 3...pipeline, 5.
... Manufacturing equipment, 6... Dry N, atmosphere forming device, 6
1...Container, 62...Dry N, inlet, 63...Dry N. Outlet, 65... Dry N, spray pipe, 66... Spray port.

Claims (3)

[Claims] (1) Condensation prevention structure for a liquid nitrogen supply system equipped with a dry N_2 atmosphere forming device that forms a dry N_2 atmosphere around a pipeline between a liquid nitrogen tank and the device. (2) The liquid nitrogen according to claim 1, wherein the dry N_2 atmosphere forming device includes a shielding member provided around the pipeline, and forms a dry N_2 atmosphere between the shielding member and the pipeline. Condensation prevention structure for supply system. (3) The above dry N_2 atmosphere forming device is a dry N_2 atmosphere forming device.
2. The dew condensation prevention structure for a liquid nitrogen supply system according to claim 1, comprising a spray device for spraying nitrogen gas toward the pipeline.