JPS63176876A - Laminated metal ring - Google Patents

Abstract

PURPOSE:To aim at enhancing the sealing characteristic and reliability of a laminated metal ring for sealing a flange or the like by arranging metal materials in such a joint configuration that their pressing forces against the associated contact surface are increased due to a difference in thermal expansion therebetween. CONSTITUTION:A metal material 1'A having a thermal expansion coefficient alpha'A is obliquely jointed to a metal material 1'B having a thermal expansion coefficient alpha'B(alpha'A>alpha'B) at the joint surface 1'ab, so as to form an integrally formed laminated ring 1' which is fitted in a flange groove 6. Further, a cover 7 is applied on the flange of a container body 5 by means of several bolts 8 and nuts 9 so as to give press-in deformation delta to the laminated ring 1' which is therefore fastened, and therefore the laminated ring 1' may be used as a seal ring. In this condition when a temperature rise DELTAT is effected, the metal materials 1'A, 1'B having a diameter R thermally expand by alpha'AXDELTATXR, alpha'BXDELTATXR, respectively, and then to be deformed by deltat in the thicknesswise direction so that the pressing force against the associated contact surface is increased. Thus, it is possible to enhance the sealing characteristic and reliability of the metal ring.

Description

Detailed Description of the Invention (Industrial Field of Application) The present invention is applied to locations where there are large fluctuations in self-temperature in containers, piping flanges, etc. of nuclear/thermal power equipment, other general industrial machinery, etc. This invention relates to laminated metal rings that are widely used as disc springs and the like.

(Prior art) Conventional seal rings, disc springs, etc. are manufactured from components made of a single material, and the pressing force (sealing force) of the contact surface (sealing surface) that occurs due to temperature fluctuations, etc. The reduction is dealt with by adjusting the tightening force using bolts, nuts, etc., or by installing multiple bolts in parallel.

The plating layer and flexible metal layer applied to the surface are designed to prevent rust, prevent wear, and improve conformity to the contact surface (sealing surface). It cannot be expected to compensate for the decrease in power.

(Problem to be Solved by the Invention) Generally, as the temperature rises, the elastic modulus of metal materials decreases and the spring constant decreases. The pressure decreases, contributing to a decrease in sealing performance, and in anticipation of this decrease, it is necessary to increase the tightening force of the bolt in advance, which requires strict bolt design and workability. Since the pressing force changes with the temperature, it cannot be used when there is temperature fluctuation and a constant pressing force is required.
Even if a plurality of sealing units are installed together, there is a limit to improving the overall sealing performance and reliability, and there are problems such as the structure becoming extremely complicated.

(Means for Solving Problems) The present invention is a laminated metal ring developed in order to solve the above-mentioned problems, and is a laminated metal ring in which a plurality of metal materials having different coefficients of thermal expansion are integrated by overlapping and bonding. In addition to being formed into a ring, the metal materials have a joining arrangement in which rotational force is generated in the cross section of the ring due to the difference in thermal expansion caused by temperature fluctuations, thereby increasing the pressing force against the opposing surface. This improves sealing performance and reliability by compensating for the decrease in sealing performance due to a decrease in the elastic coefficient (spring constant) that occurs due to temperature fluctuations by increasing the pressing force due to automatic rotational deformation of the ring cross section. Problems have been resolved.

(Function) When the temperature of the installation atmosphere rises or falls, a difference in the amount of thermal expansion occurs in the plurality of metal materials having different coefficients of thermal expansion of the laminated ring integrated by overlapping and bonding due to the temperature fluctuation, and the laminated ring A rotational force is generated on the cross section of the ring, causing rotational deformation in the direction of increasing the pressing force on the contact surface, and the general decrease in the elastic modulus of metal materials that occurs with temperature fluctuations, that is, a decrease in sealing performance, is the pressing force due to the rotational deformation. is compensated for by the increase in the amount of pressure, and at least a predetermined pressing force is ensured.

(Example) A basic example of the present invention is shown in FIGS. 1 and 2,
In the figure, (IA) is a metal material with a coefficient of thermal expansion (αA), (IB)
is a metal material with a coefficient of thermal expansion (αB), and a coefficient of thermal expansion (α
αB) for A) is moderately small (αA ) a13
) or large (αA<αB), the metal materials (IA) and (IB) are selected as different appropriate materials and used, and multiple metal materials (IA) with different coefficients of thermal expansion (dXd) are used. (IB) (each ring-shaped) is formed into a laminated ring (1) by overlapping and joining them, and the amount of thermal expansion that occurs between each metal material (IA) and (IB) due to temperature fluctuations. The joint arrangement is such that rotational force is generated in the rilling cross section due to the difference, and the pressing force against the opposing surface (sealing surface, not shown) increases. In the figure, (1b) is a bonding surface where the metal materials (IA) and (IB) are integrated, and the integration by bonding is performed by appropriate well-known means.

The basic embodiment of the present invention has the above-mentioned configuration, and its operation will be explained below. When the coefficient of thermal expansion is αA>αB, it is used by being deformed by pushing δ from the free state shown by the solid line in FIG. 2 and disposed in a groove or the like.

If the spring constant of the laminated ring (1) is k, then the pressing force P=
δk is generated. In this state, if the longitudinal elastic modulus increases by α (<1.0) times due to the temperature rise ΔT in the installation atmosphere, the pressing force will decrease by δk (1 - α), but the laminated ring (1) is the temperature rise ΔT from the free state
Then, the metal material (IA) tries to stretch more than the metal material (IB), and a rotational force is generated that lifts up the ring cross section as a whole, causing rotational deformation (clockwise rotation in the figure), increasing the height by δ, and pushing it in. When the temperature rises ΔT in a state where it is arranged by deformation δ, the pressing force becomes ΔP=δt・α・k−δ(
By selecting and integrally combining different appropriate metal materials (IA) and (IB) so that l−α)k increases and ΔP>0, the elastic modulus that occurs at least as the temperature increases The decrease in pressing force due to the decrease in is compensated for.

In the case of a decrease in the temperature of the atmosphere, select the metal materials (IA) and (IB) so that the coefficient of thermal expansion is αA<αB, and also select the thermal expansion that occurs as the temperature of the metal materials (IA) and (IB) decreases. By ensuring a suitable amount difference, rotational deformation of the ring cross section occurs to sufficiently supplement the pressing force, and similar effects can be obtained.

(Other Examples) Figures 3 and 4 show an example of a laminated full-area ring in the shape of a countersunk. metal material (1'B) to the joint surface (1'
(!, A) is formed into a laminated ring (1') integrated by overlapping bonding, and the ring is, for example, colored with a coefficient of thermal expansion α'A>α, and is provided on the end face of the container body (5). The lid is placed on the flange of the container body (5) with a plurality of bolts (8), nuts (9), etc., and the tightening force of the bolts (8) is applied to the lid. The lid is disposed by applying the above-mentioned indentation deformation δ to the laminated ring (1) through force, and is used as a seal ring at the flange portion of the container body (5).

In the laminated metal ring, when the temperature rises ΔT, the coefficient of thermal expansion (αr) of the metal material (IA) becomes lower than that of the metal material (1'B
) is larger than the coefficient of thermal expansion (α), and the metal material (1'A) is integrally joined at the joint surface (1'α, Therefore, due to the temperature rise ΔT, the metal material (1'A) becomes α'A, R・ΔT
, the average radius R of the metal material (1'B) will increase by α'B, R・ΔT, and the difference in free elongation of each metal material R・ΔT2 (α′A − α′B) , when the metal material (5) tries to expand outward relative to 1 cm, a rotational force of clockwise rotation as shown in the diagram is generated on the ring cross section, and in order to restrain it, a force is applied to the contact surface (seal surface). Pressing force is increased and sealing performance is improved.

In addition, another embodiment shown in FIG. 5 is made of a metal material having a different coefficient of thermal expansion (
Furthermore, as in another embodiment shown in FIG.
0A), (20B) and (20C) (αA, αB
, αC) formed by overlapping bonding can also be designed for temperature reduction as described above.

In each of the above embodiments, the joint surfaces of the metal materials can be integrally joined by various known means, and even if the longitudinal elastic modulus changes due to temperature fluctuations, the longitudinal elastic modulus remains almost constant even if the longitudinal elastic modulus changes due to temperature fluctuations. It can be designed to apply a pressing force of .

(Effects of the Invention) The present invention has the above-described configuration, and when the temperature of the atmosphere in which it is installed changes, the cross section of the ring changes due to the difference in thermal expansion of each metal material integrated by overlapping. Rotational force is generated and rotational deformation occurs in the direction of increasing the pressing force on the contact surface,
The decrease in pressing force caused by an increase or decrease in the modulus of longitudinal elasticity is fully compensated for by the automatic increase in pressing force caused by the rotational deformation, and the sealing performance and reliability are significantly improved, and the simple structure reduces costs. This results in significant savings and improved reliability.

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 partial cross-sectional view showing a basic embodiment of the present invention, FIG. 2 is a partial cross-sectional view explaining the operating principle of FIG. 1,
FIG. 3 is a longitudinal sectional view showing another embodiment and its arrangement state, FIG. 4 is an enlarged sectional view of the main part of FIG. 3, FIG. 5 is a cross sectional view showing another embodiment, and FIG. FIG. 7 is a cross-sectional view showing another example. 1.1, 10, 20: Laminated rings IA, IB, xh, 1'E3. IOA, IO
B, 20A, 20B, 200: Metal material 1α,
b, 1 unit, b: joint surface

Claims (1)

[Claims] It is formed into a laminated ring by integrating multiple metal materials with different coefficients of thermal expansion by overlapping and bonding, and
A laminated metal ring characterized in that the metal materials are joined to each other so that a rotational force is generated in the cross section of the ring due to a difference in the amount of thermal expansion caused by temperature fluctuation, thereby increasing the pressing force against the opposing surface.