JPH0334527Y2 - - Google Patents

Description

[Detailed Description of the Invention] (Industrial Application Field) The present invention relates to a cryogenic valve used in cryogenic equipment.

(Prior Art) FIG. 2 is a schematic diagram of a conventional low-temperature valve with vacuum insulation.

1 is a handle, 2 and 3 are seals to prevent low-temperature fluid from leaking to the outside of the valve, and 4 is a bonnet.
This also serves as an outer cylinder for the vacuum section. 5 is a vacuum inner cylinder, 6 is a vacuum insulation part for reducing heat intrusion into the low-temperature fluid, 7 is a stem, 8 is a disk made of metal, etc., and 9 is a sheet, and the disk 8 and the sheet 9 are in strong contact with each other. By doing so, the flow of the cryogenic fluid can be stopped. The sheet 9 is made of a material that is elastic and durable even at low temperatures, such as Teflon (registered trademark) or Kel-F (trade name). Reference numeral 10 designates an outer vacuum tube for reducing heat entering the low-temperature fluid, and 11 designates an inner tube through which the low-temperature fluid flows.

In the conventional low temperature valve configured in this way, the elastic force of the seat 9 decreases when the disk 8 and the seat 9 are used to open and close the low temperature section for a long period of time. or damaged, making it impossible to reliably open and close the low temperature valve.

Therefore, it was necessary to inspect the seat early and replace it with a new one.However, in the conventional structure as described above, in order to reduce the heat intrusion into the vacuum insulation part 6 of the low temperature valve, it is necessary to Since the valve is constructed by removing the valve, it is difficult for human intervention to do so, and it is very difficult to replace the seat 9. When replacing the seat, it is necessary to replace the entire low-temperature valve.

(Problems to be solved by the invention) As mentioned above, in conventional low-temperature valves, the valve is long in the stem direction, so even if the seat needs to be replaced, it is difficult to remove and install the seat alone. Therefore, there was a problem in that the entire low temperature valve had to be replaced.

The present invention was developed in view of these points, and aims to provide a low-temperature valve that improves the vacuum insulation part, makes it easy to replace only the seat, and reduces the amount of heat that enters. That is.

(Means for solving the problem) Therefore, the present invention has an inner pipe through which low-temperature fluid flows,
A vacuum section inner tube is provided which is connected to a conduit consisting of an outer vacuum tube surrounding the outer circumference and communicates with the inner tube, and a vacuum insulation section is provided around the inner tube, and a stem inside the inner tube is provided. Attach the disk to the shaft end,
In the low-temperature valve configured such that the passage of the inner pipe can be shut off by the disc and the seat, the vacuum insulation part around the inner pipe is divided in a direction perpendicular to the stem axis, and the outer peripheral part of the divided part is divided into two parts. It is covered with a sleeve that has a vacuum insulation part, and this is used as a means to solve the problem.

(Function) Since the vacuum insulation part can be divided, the human hand can reach the seat part sufficiently, making it possible to replace only the seat, and at the same time, it is also possible to inspect the vicinity of the seat part (remove dust, etc.).

(Embodiment) FIG. 1 shows an embodiment of the present invention, in which the vacuum insulation part is divided at right angles to the stem, and the divided parts are connected via a sleeve having a separate vacuum insulation part.

21 is a handle for moving the stem 27 up and down; 22 and 23 are seals to prevent low-temperature fluid from leaking to the outside; 27 is a stem; 28 is a disk attached to the tip of the stem 27; 29 is a seat; 30
Reference numeral 31 indicates an outer tube for vacuum use, and 31 an inner tube through which low-temperature fluid flows, and the above portions have the same structure as the conventional one shown in FIG.

In this embodiment, as described above, the vacuum insulation section is divided into two parts perpendicular to the stem. That is, the bonnets 24, 24' and the vacuum section inner cylinders 25, 25' are divided into two vertically, and the opposing end surfaces are connected to the annular member 3.
9,39'. Further, a stepped portion is formed on the intermediate outer circumferential surface of each of the upper and lower bonnets 24, 24', and is adapted to engage with an inner diameter portion of a coupling ring 38, 38', which will be described later. They are connected by the coupling rings 38, 38' via a generally cylindrical sleeve.

The sleeve is composed of an outer cylinder 34, an inner cylinder 35, and external threaded parts 36 and 36' provided at both upper and lower ends,
The inside is provided with a vacuum heat insulating section 37 to reduce heat intrusion.

Reference numerals 38 and 38' denote annular coupling rings with internal threads that allow the sleeves to be attached or removed in close contact with the circumferences of the upper and lower bonnets 24 and 24'; combine with Now, when trying to attach the sleeve to the upper and lower bonnets, use the upper and lower coupling rings 3.
8, 38' with the outer threaded portions 36, 36' of the sleeve until the inner diameter portions of the coupling rings 38, 38' abut against the stepped portions of the bonnets 24, 24'. Tighten '.

In addition, 32 and 33 in the figure are the upper and lower vacuum section inner cylinders 2.
This is a seal placed between the sleeve, the bonnet 24, 24', and the annular member 39, 39' to prevent the low-temperature fluid present in the gap between the sleeve 5, 25' and the stem 27 from leaking to the outside.

In this embodiment, the vacuum insulation part of the low-temperature valve body can be divided in this way, so the length of the vacuum insulation part can be shortened when replacing or inspecting the seat part, and the divided part of the vacuum insulation part can be separated. Because they are connected via a sleeve with separate vacuum insulation,
Heat intrusion from the outside into the low-temperature fluid can also be made smaller than before.

(Effects of the invention) As described in detail above, according to the invention, the seat of the low temperature valve can be easily replaced and inspected, and only the seat portion needs to be replaced, so the running cost of the valve can be reduced.

In addition, since the seat portion of the low temperature valve is accessible by human hands, dust and the like near the seat portion can be easily removed and maintenance management is also facilitated.

Further, in the present invention, since the outer periphery of the divided part of the vacuum insulation part is covered with a sleeve having a vacuum insulation part, it is possible to reduce heat intrusion from the outside and provide a structure that can withstand practical use as a low-temperature valve. Note that if there are two seats on each side between the sleeve and the divided portion, it is possible to create a structure that makes it even more difficult for the low-temperature fluid to leak.

[Brief explanation of the drawing]

FIG. 1 is a schematic sectional view of a low temperature valve showing an embodiment of the present invention, and FIG. 2 is a schematic sectional view of a conventional low temperature valve. Explanation of the main parts of the figure, 24, 24'... Bonnet, 25, 25'... Vacuum section inner cylinder, 26... Vacuum insulation section, 27... Stem, 28... Disk,
29...Sheet.

Claims (1)

[Scope of utility model registration request] A vacuum section inner cylinder is provided that is connected to a pipe line consisting of an inner pipe through which a low-temperature fluid flows and an outer vacuum pipe surrounding the outer periphery and communicates with the inner pipe, and a vacuum insulation part is provided around the inner pipe. , and a low-temperature valve configured such that a disk is attached to the end of the stem shaft in the inner cylinder, and the passage of the inner pipe can be shut off by the disk and the seat, and the vacuum insulation part around the inner cylinder is connected to the stem. A low-temperature valve characterized in that it is divided in a direction perpendicular to its axis, and the outer periphery of the divided part is covered with a sleeve having a vacuum insulation part.