JPH06201045A - Pressure vessel sealing mechanism - Google Patents

Abstract

(57) [Summary] [Purpose] To provide means for eliminating deterioration of sealing property due to deterioration of packing elasticity due to repeated pressurization and depressurization of a pressure vessel. A sealing mechanism for a high-pressure container, wherein an annular packing is arranged between the pressure container and the separating member, and a seal is formed between the container body and the separating member by radial displacement due to pressure increase in the pressure container. An expansion ring is arranged inside the annular packing for forcibly displacing the annular packing. As a result, the displacement of the annular packing is performed not only by the pressure increase in the container but also by the force of the expansion ring, so that a complete seal can be formed regardless of the deterioration of the elasticity of the annular packing.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a pressure vessel sealing mechanism for a fluid raw material used in the energy industry, the chemical industry and the like.

[0002]

2. Description of the Related Art Conventionally, as a sealing mechanism for such a pressure vessel, there are those described in, for example, JP-A-58-68550 and JP-A-2-190674.

FIG. 3 shows the outline of a high-pressure container having a pressure of 100 kg / cm ² G or more, which is described in the above publication.

This pressure vessel comprises a body portion 2 having a lid member 1 which is detachably provided on the upper and lower sides. As a sealing mechanism of the lid member 1, the outer surface of the lid member 1 and the inner surface of the body portion 2 are brought into contact with each other. A recess 3 for accommodating a seal member is provided in the portion, and an annular first-stage packing 4 and a second-stage packing 5 made of an elastic material such as rubber, Teflon, or plastic are provided therein with a slight clearance from the inner surface of the body 2. It is usual that the two-stage sealing member is attached.

As a result, the stored liquid is introduced into the container through the fluid introduction port 6 and the pressure is gradually increased to increase the pressure. With this increase in pressure, the packing is crushed and the gap between the inner surface of the body 2 is filled. That is, the sealing material is displaced in the radial direction, and the sealing property of the container is secured. After the operation of the pressure vessel, the inside of the vessel is decompressed, but the decompression causes the packing of the seal mechanism to return to its original shape, and the original radial clearance is restored again. Accordingly, when the lid member 1 is removed, the packing of the lid member 1 can be pulled up without trouble without contacting the inner surface of the body portion 2, and the next work can be started.

[0006]

However, due to the repeated pressurization and depressurization of the high pressure operation of the container, the elastic performance of the elastic material is deteriorated and the elastic restoring force is reduced, and the outer diameter of the packing during pressurization is reduced. The proper value of the incremental displacement in the direction cannot be obtained, the sealing property is lost, and leak occurs, which causes an accident.

As a countermeasure, if the gap between the outer surface of the packing and the inner surface of the body is large, the opening and closing of the lid will be very smooth, but if the radial incremental displacement during pressurization is not large, the seal will not be released. It is not possible and causes a leak.

On the other hand, if the above-mentioned gap is reduced, the radial incremental displacement at the time of pressurization may be small and a sufficient seal can be obtained, but the packing is rubbed when the lid is opened and closed, and smooth opening and closing cannot be performed.

An object of the present invention is to provide a means for eliminating the deterioration of the sealing property due to the deterioration of the elasticity of the packing due to the repeated pressurization and depressurization of the pressure vessel.

[0010]

SUMMARY OF THE INVENTION According to the present invention, an annular packing is arranged between a pressure container and a separating member, and a radial displacement due to a pressure increase in the pressure container causes a seal between the container body and the separating member. In the sealing mechanism of the high-pressure container forming the above, an expansion ring for forcibly displacing the annular packing is arranged inside the annular packing.

As means for forcibly displacing the expansion ring, a shape memory alloy with a heater is expanded and contracted in the radial direction by heating, or it is expanded in the radial direction by electric heat control during pressurization. The means of can be adopted.

Further, the expansion or contraction of the expansion ring can be automatically operated by the temperature of the seal portion and the pressure in the container.

Furthermore, a heat insulating structure may be provided around the packing portion to prevent heat dissipation or heat absorption when the expansion ring is heated or cooled.

[0014]

[Function] Since the displacement of the annular packing is performed not only by the pressure increase in the container but also by the force of the expansion ring,
A complete seal can be formed regardless of the elasticity degradation of the annular packing.

[0015]

1 to 2 show an embodiment of the present invention applied to a sealing mechanism for a lid member of a conventional pressure vessel with a lid member shown in FIG.

Embodiment 1 FIG. 1 shows an enlarged view of a sealing structure of a lid member 1 above a body 2 of a pressure vessel.

In the same figure, as in the conventional case, a packing accommodating concave portion 3 is formed on the joint surface of the lid member 1 with the body portion 2,
The inner surface is lined with a ceramic having excellent slidability and heat insulation. Two-stage packings 4 and 5 are mounted in the packing storage recess 3 and an expansion ring 8 is mounted behind them. The expansion ring 8 is made of a metal having a high expansion coefficient, for example, a Ti—Fe-based shape memory alloy, and its expansion or contraction is controlled by a cool / warm fan 9. 1
Reference numeral 0 denotes a pressure gauge for detecting an increase in the internal pressure p in the container, and 11 denotes a thermometer for detecting the temperature of the packing. Reference numeral 12 denotes a ventilation passage for sending the wind from the cooling / warming fan 9 to the expansion ring 8, and 13 denotes a ventilation outlet passage. 14, 1
Reference numeral 5 denotes an adjusting valve for controlling ventilation by receiving signals from the pressure gauge 10 and the thermometer 11, respectively.

In the seal mechanism having such a structure, when the fluid is introduced into the container and the pressure is increased, the pressure is measured by the pressure gauge 10.
The temperature of the packing is detected by the thermometer 11, and the heated air from the cool / warm air blower 9 passes through the ventilation passage 12,
The expansion ring 8 is heated and expanded to prompt the packings 4 and 5 to undergo a corresponding radial incremental displacement.

The reduction of the incremental displacement in the radial direction due to the deterioration of the packing is adjusted by the expansion of the expansion ring 8 so that the complete sealed state is always maintained.

After the pressurization is finished and a predetermined process, that is, the holding pressure is completed, the pressure reduction is started. With the pressure reduction, cold air is supplied from the cool / warm air blower 9 to cool the expansion ring 8. When the internal pressure of the container becomes zero, the expansion ring 8 also returns to the initial shape, so that the packing also has the initial shape, the radial gap is properly maintained, and the lid is smoothly opened and closed.

Embodiment 2 Although FIG. 2 is basically the same as FIG. 1, it shows a mechanism for performing heating by an electric heater 16 instead of a heating machine. It has achieved rapid heating by. In the figure, when the pressure gauge 10 detects the pressure increase in the container, the power source 17 is turned on by the detection signal, the electric heater 16 is heated, and the expansion ring 8 expands to cause the packings 4 and 5 to move to the body portion 2. Press on the inner surface to form a perfect seal.

When the high pressure maintenance is completed and the seal is released, the cool / warm air blower 9 is operated to blow cold air through the air passage 12 onto the expansion ring 8 to reduce it and return it to its original position. A gap is formed between the member 1 and the body portion 2 so that the removal of the lid member 1 is not hindered.

As described above, even if the packings 4 and 5 are deteriorated and the elasticity thereof is reduced, the expansion ring 8 presses the inner surface of the body 2 to complete the space between the lid member 1 and the inner surface of the body 2. Expansion ring 8 at the end of high pressure operation
By cooling and shrinking, the gap is surely re-formed between the packings 4 and 5 and the inner surface of the body portion 2 so as not to hinder the removal of the lid member 1.

In the above embodiment, an example in which the packing members 4 and 5 are attached to the lid member 1 has been described.
It is possible to adopt a form in which packings 4 and 5 are attached to the inner surface of the body portion 2 instead of the side, which is advantageous when the diameter of the lid member 1 is small.

When it is not necessary to immediately move the packing back after high-pressure operation, natural cooling can be performed without providing a special cooling device, which simplifies the equipment.

When the processing temperature inside the container is high, the expansion ring expands due to the heat conduction of the container. Expansion means are not necessary.

[0027]

The present invention has the following effects.

(1) Since the packing can be forcibly displaced in the radially outward direction with the attached member such as the lid member closed, leakage can be completely prevented.

(2) Since the packing can be returned to its original state when it is opened and closed, a radial gap can be secured with a margin, and the packing is not damaged when the lid member is opened and closed. Further, the structure is relatively simple, and can be easily applied to any type of pressure vessel.

(3) Since the radial increment of the packing can be controlled according to the pressure of the content liquid, the packing is not excessively deformed and the life is extended.

[Brief description of drawings]

FIG. 1 shows an embodiment of a sealing mechanism of the present invention.

FIG. 2 shows a second embodiment of the sealing mechanism of the present invention.

FIG. 3 shows an example of a conventional pressure vessel.

[Explanation of symbols]

 1 Lid member 2 Body part 3 Packing storage recess 4, 5 Packing 6 Fluid inlet 7 Lining 8 Expansion ring 9 Cooling and warming fan 10 Pressure gauge 11 Thermometer 12 Ventilation path 13 Ventilation exit path 14, 15 Regulator valve 16 Electric heater 17 Power source

Claims (1)

[Claims] 1. A sealing mechanism for a high-pressure container, wherein an annular packing is arranged between the pressure container and the separating member, and a seal is formed between the container body and the separating member by radial displacement due to pressure increase in the pressure container. A sealing mechanism for a pressure vessel, wherein an expansion ring for forcibly displacing the annular packing is provided inside the annular packing.