JP3279026B2 - Elastic flange structure for pressure vessels - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an elastic flange structure for a pressure vessel, in which a surface pressure portion is formed on the inner and outer peripheral sides of a flange so that only the surface pressure portion comes into contact with the flange. A larger surface pressure can be generated on the inner peripheral side by bending and tightening the flange with the part retracted.

[0002]

2. Description of the Related Art A connection portion of a pressure vessel is often connected by being provided with a flange structure. For example, as shown in FIG. 5, flanges 1 and 2 which come into surface contact with each other are provided and tightened with bolts. The connection is performed and the flanges 1, 2
Is made to have a uniform surface pressure distribution P1 over the entire surface.

When a pressure vessel to which a high pressure is applied is connected by using such a flange structure, both flanges 1 and 2 are connected by a pressure load due to an internal pressure during operation or the like, as shown by a two-dot chain line in FIG. In addition, the surface pressure is slightly increased at the outermost peripheral portion of the sealing surfaces of the flanges 1 and 2, but the contact area of the flanges 1 and 2 is large (the pressure per unit area is small). As P2 becomes smaller toward the inside, the sealing performance of the entire flange deteriorates.

To prevent this, the flanges 1, 2
It is necessary to increase the thickness of the steel sheet so that deformation due to internal pressure does not occur, and to increase the tightening force using a large bolt.

[0005]

However, increasing the thickness of the flanges 1 and 2 or increasing the tightening force with a large bolt increases the weight of the flange structure and increases the size of the flange structure. Large installation space must be secured with the development.

In particular, in a high-pressure vessel for a rocket, for example, a turbo pump for liquid hydrogen or liquid oxygen, a casing 3 for a driving gas and a turbine casing 4 as shown in FIG. In the flange structure 5, the weight needs to be reduced and the mounting space is restricted. Therefore, the flanges 6 and 7 are made thicker or larger to prevent deformation of the flanges 6 and 7, and the sealing performance of the flange structure 5 is improved. Cannot be improved.

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned problems of the prior art, and is intended to reduce the weight and at the same time prevent deformation and improve the sealing property. It is intended to provide an elastic flange structure.

[0008]

In order to solve the above-mentioned problems, an elastic flange structure for a pressure vessel according to the first aspect of the present invention is provided at a connecting portion of pressure vessels to which an internal pressure is applied, and is brought into contact with each other and tightened. In a flange structure, a surface pressure portion that generates a surface pressure by being brought into contact with the other flange is formed at two locations on an outer peripheral side and an inner peripheral side of one flange,
Of these surface pressure portions, the surface pressure portion on the outer peripheral side is formed by being retracted from the inner peripheral side, and the surface pressure portion on the inner peripheral side of the one flange is further formed.
Slightly retracted from the surface pressure part on the inner peripheral side to the outer peripheral side of the part
An auxiliary surface pressure part is formed to share the surface pressure of the side surface pressure part .
Sharing a surface pressure portion is greater than surface pressure of the outer peripheral side to the spare auxiliary surface pressure portion
It is characterized in that it is caused to occur.

[0009]

[0010]

According to the elastic flange structure for a pressure vessel according to the first aspect, a surface pressure portion for generating a surface pressure by being brought into contact with the other flange is formed at two positions on the outer peripheral side and the inner peripheral side of one flange. Of the surface pressure portions, the surface pressure portion on the outer peripheral side is formed by being retracted from the inner peripheral side , and
On the outer peripheral side of the inner peripheral side surface pressure part than the inner peripheral side surface pressure part.
Auxiliary surface that is recessed to share the surface pressure of the inner peripheral surface pressure part
Pressure section is formed, and when the flanges are tightened, the outer peripheral side is bent so that surface pressure is generated on the outer peripheral side. Can be generated by sharing a surface pressure greater than the surface pressure portion of
Even when a high internal pressure is applied, the flange is deformed so as to open, and the inner peripheral surface pressure portion is prevented from being deformed to improve the sealing performance.

[0011]

With the elastic flange structure for the pressure vessel, it is possible to make the flange thinner than the flange structure which seals by surface contact, thereby achieving a great reduction in weight and size.

[0013]

Embodiments of the present invention will be described below in detail with reference to the drawings. 1 and 2 show a reference example of an elastic flange structure for a pressure vessel according to the present invention. FIG. 1 (a) is a sectional view before assembling, FIG. 1 (b) is a sectional view after assembling, and FIG. It is a detailed sectional view at the time of applying to the elastic flange structure of the turbo pump for oxygen and liquid hydrogen.

The elastic flange structure 10 for a pressure vessel
For the purpose of reducing the weight, the flange is forcibly bent to give a displacement, and by utilizing this reaction force, the sealing performance is maintained while the conventional flange structure (see FIG. 5) is used.
This is to make a smaller flange.

In this elastic flange structure 10, one of the flanges 11 has a flat connection surface, and the thickness of the flange itself is the same as that of the flange used under the operating conditions of the pressure vessel used so far. It is thinner and smaller.

The flange 12 which comes into contact with and is fastened to the flange 11 has ring-shaped surface pressure portions 13 and 14 formed on the inner peripheral side and the outer peripheral side, respectively, and the intermediate portion is in a retracted state. Only the two surface pressure portions 13 and 14 come into contact with the flange 11.

Of these inner and outer surface pressure portions 13 and 14,
The outer peripheral surface pressure portion 14 is formed so as to be slightly retracted inward with respect to the inner peripheral surface pressure portion 13, and the thickness itself of the flange 12 is thinner than a conventional flange.
It is getting smaller.

The surface pressure portion 13 on the inner peripheral side of the flange 12
A seal groove 15 is formed on the outside of the housing so that a sealing material can be mounted.

The ring-shaped width B of these surface pressure parts 13 and 14
The amount of forced displacement (drawing amount) of the surface pressure portion 14 on the outer peripheral side may be appropriately selected depending on the operating conditions of the pressure vessel using the elastic flange structure 10, and, for example, a turbo pump for liquid oxygen / liquid hydrogen. When using an elastic flange structure, the flange outer diameter is about 300 mm and the internal pressure is 240 kg / cm ²
When the temperature is about 850K, the width of each surface pressure part should be
The displacement is about 3 to 4 mm and the forced displacement is about 0.2 to 0.4 mm.

In such an elastic flange structure 10 for a pressure vessel, before assembly, as shown in FIG. 1A, when the flange 11 and the flange 12 are brought into abutting condition, the inner surface pressure is reduced. When the portion 13 contacts the flange 11, a gap is formed between the portion 13 and the surface pressure portion 14 on the outer peripheral side according to the drawing amount.

From this state, the flanges 11, 1 are bolted.
2 to bend the flange 12 by an amount corresponding to the gap on the outer peripheral side to forcibly displace the flange 12 so as to come into contact with the flange 11, and then further tighten the outer peripheral surface as shown in FIG. When the surface pressure P3 is generated in the pressure portion 14, the surface pressure portion 13 on the inner peripheral side has a large surface pressure P due to a difference in the amount of protrusion.
4 occurs.

When the internal pressure is applied after the flanges 11 and 12 are tightened in this way, the inner peripheral sides of the flanges 11 and 12 are deformed so as to be opened, but a large surface pressure P4 is generated in advance in this portion. Therefore, although the value is reduced to P4a, the surface pressure itself can be secured, and at the surface pressure portion 14 on the outer peripheral side, the surface pressure P3 increases to P3a due to the deformation due to the internal pressure.

Therefore, even when the internal pressure is applied, the surface pressures P4a and P3a can be secured on the inner and outer peripheral surface pressure portions 13 and 14, and the sealing performance is maintained by preventing the deformation of the flange 12 and the seal groove 15. can do.

Further, since the thickness and size of each of the flanges 11 and 12 of the elastic flange structure 10 are small, the weight can be reduced and the mounting space can be reduced.

Such an elastic flange structure 10 is used, for example, as shown in FIG. 2 as an elastic flange structure of a turbo pump for liquid oxygen and liquid hydrogen, and is used in a portion corresponding to the flange described in FIG. Is done.

Case 1 in Table 1 shows the calculated results of the surface pressure and the displacement of each part when these flange portions were used and the results of experiments.

[0027]

[Table 1]

As is apparent from Case 1 in Table 1,
The seal characteristics are good, and a large surface pressure can be generated at the inner peripheral surface pressure portion (in Table 1, the lip surface pressure at the time of assembly) at the time of assembly. It can be seen that it can be ensured, and this point confirms that the sealing property can be maintained well.

Next, an embodiment of the elastic flange structure for a pressure vessel according to the present invention will be described with reference to FIGS. 3 and 4. The same parts as those in the above-mentioned reference example are denoted by the same reference numerals and description thereof is omitted.

In this elastic flange structure 20 for a pressure vessel, the inner and outer peripheral surface pressure portions 13 and 14 are formed on the flange 12 which is fastened to the flange 11, and the auxiliary surface pressure portion 21 is provided on the outer peripheral side of the seal groove 15 of the flange 12. Is formed in a ring shape, and is formed at a position intermediate between the inner peripheral surface pressure portion 13 and the outer peripheral surface pressure portion 14, that is, slightly retracted from the inner peripheral surface pressure portion 13.

Therefore, by forming the auxiliary surface pressure portion 21, when the flange 11 is fastened to the flange 12, the surface pressure generated in the inner peripheral surface pressure portion 13 is distributed to the auxiliary surface pressure portion 21. Can be done.

The ring-shaped width B1 and the amount of retraction (the amount of forced displacement) of the auxiliary surface pressure portion 21 may be selected as appropriate depending on the operating conditions of the pressure vessel using the elastic flange structure 20, for example. When the elastic flange structure of the turbo pump for liquid hydrogen is used, the flange outer diameter is 300mm
When the internal pressure is about 240 kg / cm ² and the temperature is about 850 K, the width of each surface pressure part is about 3 to 4 mm and the forced displacement is about 0.10 mm.

In such an elastic flange structure 20 for a pressure vessel, before assembly, as shown in FIG. 3A, when the flange 11 and the flange 12 are brought into contact with each other, the inner peripheral surface pressure is reduced. When the portion 13 is in contact with the flange 11, a gap corresponding to the drawing amount is formed between the portion 13 and the outer surface pressure portion 14, and the surface pressure portion is also formed between the portion 13 and the intermediate auxiliary surface pressure portion 21. A gap smaller than 14 is formed.

From this state, the flanges 11, 1 are bolted.
2 to bend the flange 12 by the gap on the outer peripheral side and forcibly displace it so as to come into contact with the flange 11, and then further tighten the outer peripheral surface as shown in FIG. When the surface pressure P5 is generated in the pressure portion 14, the large surface pressure P
6 and a surface pressure P7 which is smaller than the inner surface pressure portion 13 but larger than the outer surface pressure portion 14 is also generated in the intermediate auxiliary surface pressure portion 21.

After the flanges 11 and 12 are tightened in this way, when an internal pressure is applied to the elastic flange structure 20, the inner peripheral sides of the flanges 11 and 12 are deformed so as to be opened. Since P6 is generated, the surface pressure itself can be secured although the value becomes P6a, and the surface pressure portion 1 on the outer peripheral side can be secured.
In No. 4, the surface pressure P5 increases to P5a due to the deformation due to the internal pressure, and the auxiliary surface pressure portion 21 can secure a certain surface pressure P7a although the surface pressure P7 changes.

Therefore, even if the internal pressure is applied, the surface pressures P6a, P5a are applied to the inner and outer peripheral surface pressure portions 13, 14 and the auxiliary surface pressure portion 21.
Further, the surface pressure P7a can be ensured, and the deformation of the flange 12 and the seal groove 15 can be prevented to maintain the sealing performance.

By forming the auxiliary surface pressure portion 21, the surface pressure P6 of the inner surface pressure portion 13 at the time of assembly can be reduced as compared with the case where the auxiliary surface pressure portion 21 is not formed. For example, as in the case of stopping from a high-temperature operation state, even when the temperature is high and close to the time of assembling without internal pressure, even if the material strength decreases with high temperature, the inner peripheral side surface pressure portion 13 does not It can be used without sagging.

Further, since the thickness and size of each of the flanges 11 and 12 of the elastic flange structure 20 are small, the weight can be reduced and the mounting space can be reduced.

Such an elastic flange structure 20 is used, for example, as shown in FIG. 4 as an elastic flange structure of a turbo pump for liquid oxygen and liquid hydrogen, and is used for a portion corresponding to the flange portion described in FIG. Is done.

The results of calculations and experiments on the surface pressure and displacement of each part when used for these flange portions are shown in Case 2 in Table 1.

As is clear from Case 2 in Table 1,
The sealing property is good, and a smaller surface pressure can be generated in the inner peripheral surface pressure portion (in Table 1, the lip surface pressure at the time of assembly) as compared with the case 1 at the time of assembly.
In addition, it can be seen that the amount of sag can be made extremely small, and this point confirms that the sealing property can be maintained more favorably.

In the above-described embodiment, the case of the flange structure of the turbo pump for liquid oxygen and liquid hydrogen has been described as an example. .

The present invention is not limited to the above-described embodiment, and each component may be changed without departing from the scope of the present invention.

[0044]

According to the elastic flange structure for a pressure vessel according to the first aspect of the present invention, as described above specifically with one embodiment , two flanges of one flange are provided on the outer peripheral side and the inner peripheral side. To form a surface pressure portion that is brought into contact with the other flange to generate surface pressure, and of these surface pressure portions, the surface pressure portion on the outer peripheral side is formed by being retracted from the inner peripheral side , and
The inner peripheral surface on the outer peripheral side of the inner peripheral surface pressure part of one flange
Slightly retracted from the pressure part to share the surface pressure of the inner peripheral surface pressure part
Since the auxiliary surface pressure portion is formed , the outer peripheral side is bent when the flanges are tightened so that surface pressure is generated on the outer peripheral side. Can be generated by sharing a greater surface pressure than the outer peripheral surface pressure portion, and can be deformed to open the flange even when high internal pressure is applied, or to prevent deformation of the inner peripheral surface pressure portion and seal Performance can be improved.

[0045]

With this elastic flange structure for a pressure vessel, it is possible to make the flange thinner than a flange structure that seals by surface contact, thereby achieving a significant reduction in weight and size.

[Brief description of the drawings]

Participation resilient flange structure for a pressure vessel of Figure 1 the invention
According to the example, (a) is a sectional view before assembling, and (b) is a sectional view after assembling.

Participation resilient flange structure for a pressure vessel of Figure 2 the invention
The Reference Example is a detailed cross-sectional view of the application of the elastic flange structure of the turbo pump for liquid oxygen and liquid hydrogen.

[3] relates to an embodiment of the elastic flange structure for pressure vessels of this inventions, (a) cross-sectional view before assembly, the (b) is a sectional view after assembly.

4 is a detailed cross-sectional view of the application of an embodiment of a resilient flange structure for pressure vessels of this inventions to the elastic flange structure of the turbo pump for liquid oxygen and liquid hydrogen.

FIG. 5 is a sectional view of a conventional flange structure.

FIG. 6 is a sectional view of a turbo pump for liquid oxygen and liquid hydrogen as an example of a target to which the elastic flange structure for a pressure vessel of the present invention is applied.

[Explanation of symbols]

 Reference Signs List 10 Elastic flange structure for pressure vessel 11 Flange 12 Flange 13 Inner peripheral surface pressure part 14 Outer peripheral surface pressure part 15 Seal groove 20 Elastic flange structure for pressure vessel 21 Auxiliary surface pressure parts P1 to P7 Surface during assembly Pressure P1a to P7a Surface pressure during operation

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int. Cl. ⁷ , DB name) F16J 12/00

Claims (1)

(57) [Claims] 1. A flange structure provided at a connecting portion of a pressure vessel to which an internal pressure is applied and tightened by being brought into contact with each other. A pressure generating portion for generating pressure is formed, and an outer pressure surface pressing portion of the pressure generating portions is retracted from an inner peripheral side , and further formed on an inner peripheral side of the one flange.
Slightly retracted to the outer peripheral side of the surface pressure part
Auxiliary surface pressure part that shares the surface pressure of the inner peripheral surface pressure part with
And, the pressure vessel is shared surface pressure portion is greater than surface pressure of the inner peripheral side surface pressure portion and the outer auxiliary surface pressure portion of the flexed the outer peripheral side when tightening the flanges together, characterized in that to produce in Elastic flange structure for