JPH0421078Y2 - - Google Patents

Description

[Detailed description of the invention] [Industrial field of application] This invention relates to a liquid level gauge, and more specifically, the column of a liquid level gauge for a cryogenic liquid storage tank is double-walled, and there is a space between the two walls. The present invention relates to a magnetic liquid level gauge that is capable of preventing vaporization of cryogenic liquid by creating a heat insulating space by creating a vacuum.

[Prior Art] For example, in a liquid level gauge for a tank that stores two or more types of liquids with different boiling points, a cylindrical container with a see-through window surrounds a liquid chamber that constitutes a liquid level gauge that looks directly at the liquid level. The space between the liquid chamber and the cylindrical container is insulated by evacuating the space through a drain and air vent pipe that communicate with the space, and the liquid chamber is cooled by the atmosphere. A structure for preventing this is disclosed in Japanese Utility Model Application Publication No. 58-6229.

[Problems to be solved by the invention] By using the double-wall vacuum insulated space described above,
This can prevent the liquid chamber that forms the liquid level gauge from being cooled by the atmosphere, but when used as a level gauge in a tank that stores cryogenic liquids such as liquefied ethylene, it is possible to prevent the liquid chamber from being cooled by the atmosphere. The heat rays reach the cryogenic liquid inside the liquid chamber.

Furthermore, if the liquid level gauge is a magnetic type level gauge as described in Japanese Patent Publication No. 58-2605, if this is used as a level gauge for a low boiling point liquid, it will be vaporized by external heat and large bubbles will be generated. Therefore, there is a problem in that the magnetic float dances, causing the display body to behave abnormally and making the display unclear.

The object of this invention is to solve the above-mentioned problems that occur when determining the liquid level of cryogenic liquid using the magnetic liquid level gauge described above.

[Means for Solving the Problems] The above-mentioned problems include an inner column formed in a pipe shape made of non-magnetic material and containing the liquid whose liquid level is to be measured, and a movable column inside the inner column. A float having a magnet inserted therein and magnetized in the vertical direction, an inner stem tube protruding from the upper and lower circumferential surfaces of the inner column, and an outer stem tube covering each of these inner stem tubes, and non-contact. A pipe-shaped outer column made of magnetic heat-reflecting material and a number of rotating indicators made of magnetic material are rotated inside a non-magnetic casing arranged along the length of the outer surface of the outer column. This can be achieved by vacuum insulating the space between the inner column and the outer column.

[Function] The magnetic liquid level gauge of this invention evacuates the space formed between the inner column and the outer column, thereby creating a vacuum-insulated space on the outside of the inner column, and creating a space inside the inner column by conduction and convection. This prevents the magnetic float from dancing inside the inner column due to external heat entering and causing the cryogenic liquid to vaporize under the influence of the external temperature and generate large bubbles, and to rotate the liquid level as the magnet moves. The liquid level can be displayed by changing the external coloring position by 1/2 rotation of the moving liquid level indicator.

[Example] As shown in FIG. 1, the magnetic liquid level gauge of this invention has a cylindrical inner column 11 made of a non-magnetic material and having inner stems 12 and 13 at both ends.
A float 15 whose magnetization direction is integral with the magnet 14 in the length direction of the inner column 11 is placed inside, and surrounds the inner column 11 including the inner stem tubes 12 and 13. An outer column 16 is provided which forms a space 17 in the outer column.
A plug 20 for inserting the float 15 into the inner column 11 through a space 17 is screwed onto the lower end of the outer column 16, and an exhaust pipe 18 with a valve 19 is attached to the side wall.

In the column 1 having the vacuum-insulated space 17, there is a liquid level indicator 3 in which a rotation indicator 2 is rotatably mounted in a non-magnetic casing 31 as shown in FIGS. 2 and 4. installed.

As shown in FIGS. 3 and 4, the rotation indicator 2 has a pair of indicator plates 21 and 22 made of a non-magnetic material, each having a semicircular curved part formed in the center, facing each other. , 22 is fitted with a cylindrical magnet 25A having the shaft 25 as the center, and the surface of the indicator plate 21 is colored, for example, red, and the surface of the indicator plate 22 is colored, for example, in white. It is colored.

As shown in FIG. 4, this rotation indicator 2 has through-holes in an indicator plate groove 32 of a housing 31 formed of a non-magnetic material and having a U-shaped cross section, with a pitch larger than the vertical width of the rotation indicator. A pair of bearing plates 34a opening 33,
A predetermined number of rotation indicators 2 are pivotally arranged between the bearing plates 34b by the shaft 25, and attached along the inner surfaces of the pair of vertical members 35a and 35b forming the grooves. A pair of end plates 36 at both ends
A, 36b and a transparent member 37 are attached to the opening surface of the indicator plate groove 32 to form a liquid level indicator 3 that is easy to assemble.

2 and 4 show the mounting configuration of the magnetic liquid level gauge of this invention, in which the liquid level indicator 3 is placed in an inner column 11 made of a non-magnetic material, and the direction of magnetization is the length of the inner column 11. Column 1 containing float 15 integrated with column 14 in horizontal direction, that is, vertical direction.
It is constructed by attaching the attachment band 4 to the attachment band 4.

Note that in the figure, a indicates a welded portion, and p indicates packing.

Since the magnetic liquid level gauge of this invention is constructed as described above, the cryogenic liquid in the liquid storage tank enters the inner column 11 through the inner stem pipe 13, and as the liquid level changes, the float 15 When the float moves up and down in the length direction within the inner column 11, the magnet 14 integrated with the float 15 and the indicator plates 21 and 22 of the rotation indicator 2 are repelled and attracted depending on the polarity and rotate. However, the red and white colors painted on the magnetic plates 21 and 22 are reversed to indicate the liquid level.

In this case, the inner stem tubes 12 and 13 are surrounded by the outer stem tubes 16A and 16B, and the inner column 11 is surrounded by the outer column 16 in a space 17. Since the space 17 is double-walled and vacuum insulated, even if there is a difference between the liquid temperature and the outside temperature, there is no direct conduction or heat input through convection, which prevents large bubbles from boiling and vaporizing the cryogenic liquid. The display does not become inaccurate, and since the outer column is made of a heat ray-reflecting material such as a non-transparent material, heat rays do not enter the outer column, resulting in good heat insulation.

Note that the degree of vacuum in the space 17 may be determined depending on the liquid whose level is to be measured, and does not necessarily require a high degree of vacuum.

[Effects of the invention] This invention adopts a means to solve the above-mentioned problems, so even when used for displaying the liquid level of a cryogenic liquid, the double-wall vacuum-insulated space 17 prevents external heat from flowing into the liquid. Since the cryogenic liquid does not boil, the display does not become unclear due to the sudden rise or drop of the float due to large bubbles, and the insulation effect against heat rays is maintained well over a long period of time. .

[Brief explanation of drawings]

The figures show one embodiment of this invention; Fig. 1 is a cross-sectional view of the column, Fig. 2 is a side view showing the structure of a magnetic liquid level gauge with a part removed;
FIG. 3 is an enlarged sectional view of the rotation indicator, and FIG. 4 is a front view with a portion of the liquid level gauge cut away. 11... Inner column, 16A, 16B... Outer stem tube, 12, 13... Inner stem tube, 17...
... Space, 14 ... Magnet, 2 ... Rotation indicator, 15 ... Float, 3 ... Liquid level indicator, 16
...Outer column, 31...Non-magnetic casing.

Claims (1)

[Scope of utility model registration request] In a magnetic float type liquid level gauge, an inner column 11 is formed in a pipe shape from a non-magnetic material and contains a liquid whose liquid level is to be measured;
A float 15 having a magnet 14 movably inserted into the inner column 11 and magnetized in the vertical direction; inner stem tubes 12 and 13 protruding from the upper and lower peripheral surfaces of the inner column 11; The outer column 1 has outer stem tubes 16A and 16B that cover the inner stem tubes 12 and 13, respectively, and is made of a non-magnetic heat ray reflective material in a pipe shape.
6, and a liquid level indicator in which a large number of rotary indicators 2 made of magnetic material are rotatably housed in a non-magnetic casing 31 disposed along the length of the outer surface of the outer column 16. a space 17 between the inner column 11 and the outer column 16.
A magnetic liquid level gauge characterized by vacuum insulation.