JPS6038239B2 - Manufacturing method of metal gasket - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method of manufacturing a metal gasket that airtightly seals between flanges and the like.

A conventional metal gasket is explained with reference to Figs. 1, 2, and 3. In Fig. 1, a and b are the pipes, c and d are flanges attached to the ends of the pipes a and b, and e and f are the flanges c. , d, and g in Figs. 1 and 2 are the same annular grooves e and f.
a metal gasket interposed between h and the flanges c,
As shown in Figure 3, a soft seal metal mirror, g3, is attached to a certain thickness over the entire inner and outer circumferential surfaces of the hollow cylindrical metal base material seal with high elasticity. After plating the metal base material 9, the same metal base material 9 is cut along imaginary conical surfaces B, B whose apex is placed on the center line A, and the metal gasket g is manufactured. Insert the same metal gasket g into the annular grooves e and f provided on the joint surfaces of the flanges c and d, and place the inner peripheral surface of the seal metal saddle on the inner peripheral surface of the annular groove e and the outer peripheral surface of the seal metal &. At the same time as contacting the outer circumferential surface of the annular groove f, the sharp edges of the seal metal saddles, & are brought into contact with the corners of the annular grooves e, f, then tighten the bolts h, and tighten the metal motherboard seals at the same time. By elastically deforming according to the tightening force, the inner circumferential surface of the seal metal & is attached to the inner circumferential surface of the annular groove e, the outer circumferential surface of the seal metal & is attached to the outer circumferential surface of the annular groove f, and the sharp edge portion of the seal metal &, & are pressed against the corners of the annular grooves e and f, respectively, to fill in the minute irregularities of the annular grooves e and f, making the inside of the ultra-high vacuum pipes a and b airtight from the outside of the pipe. After removing the bolt h and separating the flanges c and d so as to seal, the metal gasket g is taken out from the annular grooves e and f and returned to the state shown in Fig. 2 by its own spring effect. The metal gasket g can be used repeatedly by assembling the metal gasket g and sealing the insides of the pipes a and b airtight again from the outside of the pipes.

In the metal gasket g, the seal metals g2, & are formed on the inner and outer peripheral surfaces of the metal base material 9 by plating, so (1) the thickness of the seal metal scales cannot be changed freely.

(0) There was a problem in that the seal metal and the crane could not be made of any material, such as a soft alloy. Regarding item (0) in the figure, if a method such as vapor deposition is used,
Although a sensitive alloy or the like can be formed on the inner and outer circumferential surfaces of the metal base material 9, the above-mentioned item (1) is not solved. The present invention addresses the above-mentioned problems, and includes a hollow cylindrical inner seal metal having a constant thickness on the inner peripheral surface of a hollow cylindrical metal base material, and a hollow cylindrical inner seal metal having a constant thickness on the outer peripheral surface of the metal base material. A certain hollow cylindrical outer seal metal is brought into close contact with each other, and the inner circumferential surface of the inner seal metal is made of a material having a higher thermal expansion rate than the metal base material and each of the seal metals. A hollow cylindrical inner block is formed on the outer circumferential surface of the outer seal metal, and a hollow cylindrical outer block is formed of a material having a coefficient of thermal expansion smaller than that of the metal base material and each of the seal metals, respectively, through a mold release material. Then, by heating them, the metal base material and each of the seal metals are diffusion bonded, and after removing each of the blocks, the metal base material and each of the seal metals are aligned on their center lines. This method of manufacturing a metal gasket is characterized by cutting along an imaginary conical surface with an apex. An object of the present invention is to provide an improved method for manufacturing a metal gasket that can be formed in a simple manner.

As described above, the method for producing a metal gasket of the present invention involves forming a hollow cylindrical inner seal metal with a constant thickness on the inner circumferential surface of a hollow cylindrical metal matrix, and forming a hollow cylindrical inner seal metal with a constant thickness on the outer circumferential surface of the metal matrix. A cylindrical or hollow cylindrical shape in which the outer seal metals of a certain hollow cylindrical plate are brought into close contact with each other, and the inner circumferential surface of the inner seal metal is made of a material with a coefficient of thermal expansion larger than that of the metal base material and each of the seal metals. A hollow cylindrical outer block made of a material having a coefficient of thermal expansion smaller than that of the metal matrix and each seal metal is brought into close contact with the outer circumferential surface of the outer seal metal via a release hole. Next, these are heated to diffusion bond the metal base material and each of the seal metals, then each of the blocks is removed, and then the metal base material and each of the seal metals are bonded to the apex on their center line. Since the seal metal is cut along an imaginary conical surface, it is possible to form a seal metal of any material to any thickness on the inner and outer circumferential surfaces of the metal base material.

Next, the method for manufacturing a metal gasket of the present invention will be explained with reference to an embodiment shown in Figs. 4 and 5. t. Inner seal metal formed into a hollow cylindrical shape, {3' is an outer seal metal formed into a hollow cylindrical shape with a constant thickness by Setsumura, and '4) is an inner block formed into a cylindrical shape from aluminum material. , [5) is an outer block formed in a hollow cylindrical shape from stainless steel material,
8, is the coefficient of thermal expansion of the metal base material 1, 62 is the inner seal metal 2, 83 is the outer seal metal 3, 84 is the inner block 4, and B5 is the outer block 5. The coefficient of thermal expansion of parts 1 to 5 is 6
4>82,8・,33,85.

When manufacturing a metal gasket, the inner seal metal 2 is closely attached to the inner circumferential surface of the metal base material 1, and the outer seal metal 3 is closely attached to the outer circumferential surface of the metal base material 1. The inner block 4 and the outer block 5 are closely attached to the inner circumferential surface of the seal metal 3 and the outer block 5 are closely attached to the outer circumferential surface of the outer seal metal 3 through mold release materials, respectively, and then placed in a vacuum furnace (not shown).
The parts 1 to 5 are thermally expanded by heating and raising the temperature in the furnace, but the coefficient of thermal expansion of these parts 1 to 5 is 84>82, B., 33> as described above.
35, surface pressure is generated on the mutual joint surfaces,
The inner seal metal 2 and the outer seal metal 3 are diffusion bonded to the inner and outer peripheral surfaces of the metal base material 1. Next, the inner block 4 and the outer block 5 are removed from the vacuum furnace, but a release material is applied in advance to the joint surfaces between the inner seal metal 2 and the inner block 4 and the joint surfaces between the outer seal metal 3 and the outer block 5. can be inserted, and the inner block 4 and outer block 5 can be removed as they are. Next, the metal base material 1, the inner seal metal 2, and the outer seal metal 3, which have been diffusion bonded as described above, are cut along a conical surface whose apex is placed on the center line to obtain a metal gasket of the desired shape. do. Therefore, any material sealing metal 2 is used on the inner and outer peripheral surfaces of the metal base material 1.
, 3 can be formed to any thickness. Although the present invention has been described above with reference to embodiments, it goes without saying that the present invention is not limited to such embodiments, and that various design modifications can be made without departing from the spirit of the present invention. .

[Brief explanation of the drawing]

Fig. 1 is a longitudinal side view showing an example of the use of a metal gasket, Fig. 2 is an enlarged longitudinal side view thereof, Fig. 3 is a longitudinal side view showing a conventional method of manufacturing a metal gasket, and Fig. 4 is a side view according to the present invention. FIG. 5 is a longitudinal cross-sectional side view showing one embodiment of a method for manufacturing a metal gasket, and FIG. 5 is a cross-sectional plan view taken along the line V-V in FIG. 4. 1... Metal base material, 2... Inner seal metal, 3.
...Outer seal metal, 4...Inner block, 5...
・Outside block. ↑ Figure 2 Figure 3 Figure 4 Figure 5

Claims (1)

[Claims] 1. A hollow cylindrical inner seal metal with a constant thickness is provided on the inner peripheral surface of a hollow cylindrical metal base material, and a hollow cylindrical outer seal metal with a constant thickness is provided on the outer peripheral surface of the same metal base material. At the same time, a cylindrical or hollow cylindrical inner block made of a material with a coefficient of thermal expansion larger than that of the metal base material and each of the seal metals is attached to the inner peripheral surface of the inner seal metal. A hollow cylindrical outer block made of a material having a coefficient of thermal expansion smaller than that of the metal base material and the seal metals is brought into close contact with each other via a mold release material, and then these are heated to separate the metal base material and the seal metal. A method for manufacturing a metal gasket, characterized in that each seal metal is cut along an imaginary conical surface with its apex placed at its center.