JPS618642A - Method for measuring pressure of high temperature fluid - Google Patents

Abstract

PURPOSE:To permit the pressure measurement of a high temp. type using the fluid which withstands temp. higher than 350 deg.C as a sealing liquid by using Ga as the sealing liquid. CONSTITUTION:The sealing liquid contains Ga along or a Ga alloy contg. <=50% In+Sn and the balance Ga or a Ga alloy contg. <=50% Sn+Zn and the balance Ga in terms of an m.p., viscosity, coefft. of thermal expansion, thermal stability, corrosion resistance, etc. Ga-In-Sn: 11 deg.C m.p., Ga-Sn-Zn: 17 deg.C m.p. and Ga-In: 16 deg.C m.p. are particularly preferable among these Ga alloys. The increase of the max. service temp. of the conventional type from 350 deg.C up to 600 deg.C is made possible. The sealing liquid in this case contains >=50% Ga.

Description

DETAILED DESCRIPTION OF THE INVENTION Technical Field The present invention relates to high-temperature fluids, such as metal halides in the gaseous state in metal salt vaporizers and high-temperature metal sodium, lead, and soot chlorides in the molten state used as heat carriers. The present invention relates to a pressure measurement method for high-temperature fluids, such as potassium double salt, lithium chloride-sodium chloride double salt, etc.

PRIOR ART AND ITS DISADVANTAGES Pressure measurement of high temperature fluids, such as the heat transfer medium mentioned above, is important for instrumentation and control purposes. For pressure measurements of these hot fluids,
In general, heat is radiated or cooled from the impulse pipe so that the temperature of the measured fluid remains high until it reaches the pressure receiving element, and a standard pressure gauge is used as much as possible. However, the stiffness M(
In the case of a fluid to be measured that is solid or has an excessive viscosity at room temperature, use a diaphragm seal type and seal the liquid with silicone oil or mercury so that it can withstand high temperatures in the solution (gas) part. A high temperature diaphragm pressure gauge is used. This type of pressure gauge is a direct indicator type as shown in Figure 1, where 1 is the filled liquid, 2 is the diaphragm, 3 is the tightening bolt, 4 is the upper flange, 5 is the lower flange, 6 is the gasket, 7 is a pressure receiving section, and 8 is an instruction section. This type of pressure gauge cannot be used at temperatures exceeding about 350° C. when the filled liquid is silicone oil due to its high temperature, and when the filled liquid is mercury due to its boiling point.

The inventors of the present invention have been busy researching high-temperature heating media, and found it necessary to measure the pressure when controlling the flow rate, etc. of the heating medium. Generally speaking, in terms of energy efficiency,
The higher the temperature of the heat medium, the more desirable it is, but for the reasons mentioned above, it has been impossible to measure the pressure of fluids exceeding 350°C using conventional high-temperature pressure gauges. Therefore, the inventors of the present invention solved the above-mentioned drawbacks of the prior art and, as a result of studying the filling liquid, found that Ga He discovered that scales can achieve the above purpose by using them as an encapsulating liquid,
We have arrived at the present invention. Conventional preconceptions about Ga have been that it is solid at room temperature and has a large volume when solidified, that it is easily oxidized when sealed, and that it forms liquid alloys with many metals, so it has been far away from being filled in liquids. .

That is, according to the present invention, Ga alone or In 0 to 30% p is used as the sealed liquid of the diaphragm pressure gauge.
Ga alloy containing 50 or less In+Sn in the range of S n 0 to 30 q6, and the balance being Ga, or 5nO-
30%, Zn in the range of 0 to 30%, containing 50% or less of Sn+Zn, and the remainder being Ga.

In the present invention, the sealed liquid includes various simple metals, alloys, simple halides, and eutectic mixtures (compounds) of halides.
Possible factors include melting point and boiling point.

In terms of viscosity, thermal expansion coefficient, thermal stability, corrosion resistance, etc., gallium alone or indium + tin containing 50 parts or less (I
n 0-30% tS n 0-30%)
, Ga alloy with the remainder being gallium, or -'H containing 50% or less of tin + zinc (Sn0-309b, Zn0-3
0ch), the remainder being gallium.

Among these Ga alloys, Ga(62.5%)-
In(21.5%)-8n(16%): melting point 11°C,
Qa (82%) - 8n (12%) Zn (6%):
Melting point: 17°C, Ga(76%)-In(24'4): Melting point: 16°C.

50 of these gallium alone or indium + tin
Contains 5 or less, and the remainder is Ga alloy or tin + zinc
The conventional high-temperature diamond 72
It has become possible to raise the maximum operating temperature of pressure gauges from 350°C to 600°C in one fell swoop. Actually i,oo
Although it can be used up to around 0°C, the elasticity of stainless steel, which is commonly used as a diaphragm material, is 600°C.
Use above this level is undesirable as it will cause a drop.

As mentioned above, the liquid filled in the high-temperature diaphragm pressure needle of the present invention is gallium (melting point: 30°C, boiling point: 198.3°C).
), or based on gallium (on a 50-weight plate),
In (melting point 155℃, boiling point 2.000℃) 0-30
% s Sn (melting point 282°C.

Boiling point 2,260℃) 0-30%, Zn (melting point 419℃,
It is an alloy having a boiling point of 907°C) in the range of 0 to 30 as a subordinate component.

When the Ga content of these alloys is less than 50%, In,
Because the properties of Sn and Zn are strong, the low melting point (and high boiling point) of Ga disappears, so the filled liquid of the present invention should contain 5 oIs or more of Ga.

Next, the present invention will be explained in more detail with reference to examples, but the scope of the present invention is not limited to the following examples.

Example 1 Diamond 72mm 4S34. Diamond 7 Tsum Material 5US316
, +[With molding pressure indicator needle, pressure range fB0~6kJF/d
A diaphragm pressure gauge C (see Figure 1) is charged with simple Ga as a fill liquid, and then heated to 400°C in a continuous rise of aluminum chloride #c! Ig! PK installation, grinding wheel 10,
After using it for 000 hours, it was removed from the t'll JM furnace and comparatively inspected using a certified pressure gauge, and the error was 0.3% FS, and the allowable tolerance was 1.5-F8.
It was small enough to be useful.

Actual mfl12 Ga (62,5
96)-In(21,5-)-8n(161) alloy was charged, installed in a ferric chloride continuous refining furnace at 500°C, and used for a total of 10,000 hours.

Next, a comparative test was conducted in the same manner as in Example 1.
The fF tolerance was 0.2% FS, and it was suitable for optical use.

Example 3 Diameter 72 mm 34. Diamond 7, yum material 5US31
6.a: A diamond 7-trim pressure needle with a force transmitter and a pressure range of θ to 6 Yu/ctG (see Figure 2) is filled with Ga (8
2%)-8n(12%)-Zn(6%) alloy,
600℃ indium trichloride continuous valve fEffjllP
K was installed and used for a total of 10,000 hours. Next, a comparative test was conducted in the same manner as in Example 1, and the allowable tolerance was 0.21 FS, which was sufficient for use.

Example 4 Ga(765I)-In was added to the pressure needle of the same type as Example 3.
(24%) alloy was charged, a continuous antimono trichloride refining furnace 11L was installed at 400°C, and the reactor was used for a total of 1000 hours. Subsequently, a comparison test was conducted with the Ml in question and by a colleague, and the acceptable tolerance was 0.34 FS, which was sufficient for use.

[Brief explanation of drawings]

FIG. 1 is a perspective view, partially in section, of an example of a direct indication type high temperature diaphragm pressure gauge, and FIG. 2 is a schematic diagram, partially in section, of a pressure transmission type high temperature diaphragm pressure gauge. In the figure, 1-----1 filled liquid 7-----Pressure receiving part 2--
---Diaphragm 8-----One indicator 3-----
- Tighten with bolt 9 ---- One diaphragm part 4 - Upper 7 langes 10 - One - Capillary 5 -------
Lower 7 langes 11---1 Pressure transmitter 6---1 Gasket

Claims (1)

[Claims] (1) As the filled liquid of the diaphragm pressure gauge, use Ga alone or In in the range of 0 to 30% In and 0 to 30% Sn.
+Ga alloy containing 50% or less of Sn and the remainder being Ga, or Sn+ in the range of 0 to 30% Sn and 0 to 30% In
A method for measuring the pressure of a high-temperature fluid, characterized by using a Ga alloy containing 50% or less of Zn and the remainder being Ga.