JPS6241230Y2 - - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to a pressure extraction flange provided at a location where pressure is extracted from a fluid container, pipeline, etc. to a differential pressure gauge, pressure gauge, or the like.

Since the inner surface of this type of pressure extraction flange on the side of the fluid container comes into contact with the fluid, if the specifications of the fluid require corrosion resistance, the surface in contact with the fluid may be coated with titanium. FIG. 1 is a sectional view of a conventional corrosion-resistant pressure take-off flange of this type. This will be explained based on the figure. A mounting flange 1 is integrally formed with the pressure vessel, and its outer surface is made of titanium. It is lined with a formed corrosion-resistant material 2. A connection flange 4 lined with a base plate 3 also made of titanium is connected to the mounting flange 1 with bolts 6 with a gasket 5 interposed between the base plate 3 and the corrosion-resistant material 2. A diaphragm 7 made of titanium is welded to the center of the diaphragm 7 . A stainless steel mounting piece 8 is inserted into the inner hole of the boss portion 3a of the base plate 3 that is engaged with the stepped hole at the center of the connecting flange 4, and is fixed by silver soldering around the periphery and end surface. A capillary tube 9 connected to a pressure gauge or a differential pressure gauge is inserted into the center and fixed by argon arc welding. The capillary tube 9 is communicated with a pressure detection chamber 10 on the outside of the diaphragm 7 through a through hole bored in the center of the mounting piece 8 and the base plate 3, and the pressure detection chamber 10 is connected to a pressure gauge, etc. A pressure transmitting liquid such as silicone oil is sealed between the two.

In the conventional pressure extraction flange constructed in this way, the base plate 3 is also made of corrosion-resistant titanium material because the area around the welded part of the diaphragm 7 is slightly in contact with liquid. Since the mounting piece 8 made of stainless steel, which is made of a different material, is brazed to the base plate 3, due to the difference in thermal expansion coefficient between the two, it solidifies while being cooled from the brazing temperature of 780°C or higher to room temperature. There were problems in that cracks and peeling occurred in the solder material, reducing the durability of the bonded parts and making it impossible to ensure airtightness.

The present invention was developed in view of the above points, and the mounting end of the stainless steel mounting member to which the pressure transmission pipe is fixed is formed into an annular shape, and this mounting member is made of titanium, which is fixed by brazing. By providing an annular groove in the flange lining member made of aluminum to engage the annular mounting end, and forming an annular gap into which solid brazing material can be loaded, the shrinkage of stainless steel and titanium is reduced. The present invention provides a pressure extraction flange which makes it possible to accumulate internal stress in the solder material after solidification by utilizing the difference in rate, and to obtain a strong fixed part with excellent durability. Embodiments of the present invention will be described in detail below with reference to the drawings.

Fig. 2 and Fig. 3 show an embodiment of the pressure extraction flange according to the present invention, Fig. 2 is a sectional view of the fixed part between the pressure transmission pipe mounting member and the flange lining member, and Fig. 3 is also a brazed part. It is an explanatory diagram of operation.
Since the configuration other than the parts shown in FIG. 2 is the same as the conventional pressure takeoff flange shown in FIG. 1, illustration and description thereof will be omitted, and the same drawing will be used for further explanation when necessary. In the figure, the connection flange 4 of the pressure extraction flange is lined with a base plate 11 made of titanium, and an annular annular plate with a rectangular cross section is provided at a location corresponding to the opening of the connection flange 4. A groove 11a is formed. A capillary tube 9 as a pressure transmission pipe connected to a pressure gauge or a differential pressure gauge is inserted into a mounting piece 12 as a mounting member fixed to the base plate 11 and fixed by argon arc welding. At the same time, the mounting end 12a of the mounting piece 12 is formed into an annular shape with a square cross section so as to engage with the annular groove 11a. The annular groove 11a and the annular mounting end 12a are engaged with each other and brazed by means described later, and for this reason, a double annular groove in which a solder material 13 is loaded is formed between the annular groove 11a and the annular mounting end 12a. A gap 14 is formed. 12
b is a heat dissipation fin protruding from the outer periphery of the mounting top 12.

The procedure for brazing the base plate 11 and the mounting piece 12 constructed as above and its operation will be explained. In FIG. 3, before attaching the mounting piece 12, a ring-shaped solid solder material 13A is loaded into the center of the annular groove 11a of the base plate 11, and then the annular mounting end 12a of the mounting piece 12 is inserted. The annular groove 11a of the base plate 11 is engaged with the annular groove 11a. As a result of the engagement, the annular solid solder material 13 also fills the gap 14 formed on the outer periphery of the annular attachment end 12a.
Load multiple pieces of B. After preparing in this way,
When the entire joint flange 4 is placed in a vacuum furnace and heated with radiant heat of 700°C or higher, the solid solder material 14 melts,
The melted solder material 13 fills the gap 1 as shown in FIG.
Penetrates into 4. Then, when the heat is cut off and the solder material 13 is cooled, the solder material 13 solidifies, and the mounting end portion 12a and the annular groove 11a, which had expanded due to the heating, contract. In this case, since the coefficients of linear expansion of both 12a and 11a are different, such as approximately 9 for titanium and approximately 16.4 for stainless steel, the mounting end 12a is larger than the central boss of the annular groove 11a. Because of the large contraction, the gap 14 becomes narrower than when heated. Therefore, internal stress is accumulated in the compressive direction in the solder material 13 that solidifies before it reaches room temperature, and the solder material 13 is fixed in this state.
Unlike the case where the gap between the two 8 and 3a widens as the solder material solidifies as shown in the figure, cracks and peeling do not occur in the solder material 13. Even if the internal stress remaining in the solder material 13 is slightly relaxed when a high-temperature fluid is being measured,
As long as the solder material 13 is used at a temperature below its melting temperature, no failure will occur at the brazed portion.

After the mounting piece 12 is fixed to the base plate 11 in this manner, the capillary pipe 9 connected to the pressure gauge is inserted into the mounting piece 12 and fixed by argon arc welding. In this case, the temperature of the mounting piece 12 rises due to heating, but since heat is dissipated by providing the fins 12b, the heat does not reach the brazed area and deteriorate the fixing state.

As is clear from the above description, according to the present invention, the mounting end of the stainless steel mounting member to which the pressure transmission pipe is fixed in the pressure takeoff flange is formed into an annular shape, and this mounting member is attached by brazing. providing a titanium flange lining member to be fixed with an annular groove for engaging the annular attachment end;
By forming an annular gap into which a solid brazing material can be loaded in this engagement part, if the solid brazing material is loaded into the gap and then heated and melted to perform brazing, the solder material melts and then cools and solidifies. Sometimes, internal stress accumulates in the solder material due to the shrinkage rate difference between stainless steel and titanium, which reduces the gap between the solder joints. In addition to improving the properties, the durability of the pressure relief flange is significantly improved.

[Brief explanation of the drawing]

Figure 1 is a cross-sectional view of a conventional pressure extraction flange.
Fig. 2 and Fig. 3 show an embodiment of the pressure extraction flange according to the present invention, Fig. 2 is a sectional view of the fixed part between the pressure transmission pipe mounting member and the flange lining member, and Fig. 3 is also a brazed part. It is an explanatory diagram of operation. 4... Connection flange, 11... Base plate, 11
a... annular groove, 12... mounting piece, 12a... mounting end, 13... brazing material, 13A, 13B... solid brazing material, 14... gap.

Claims (1)

[Scope of utility model registration request] A pressure outlet flange comprising a mounting member made of stainless steel and to which a pressure transmission pipe is fixed; and a flange lining member made of titanium and to which the mounting member is fixed by brazing; the mounting end of the mounting member; A pressure outlet flange characterized in that the inner lining member is provided with an annular groove in which the annular mounting end is engaged so as to form an annular gap into which a solid solder material can be loaded. .