JPH05256369A - Pressure vessel - Google Patents

Abstract

PURPOSE:To improve the durability by providing 3 synthetic resin inner vessel having a flange facing outward, a metal outer vessel having a step on an opening end and a metal cover having a synthetic resin cover layer on the inner surface and interposing O rings between the flange facing outward and the step, the cover and the outer vessel. CONSTITUTION:In a metal cover 14, a synthetic resin cover layer is formed on the surface facing to the storing space of a synthetic resin inner vessel 12 and the flange 20 facing outward of the inner vessel 12. Therefore, the corrosion of the cover 14 caused by, for example, a corrosive liquid and the like storing in the inner vessel 12 can be prevented. A first 0 ring 15 is interposed between the flange 20 facing outward and the step 26 of a metal outer vessel 13. Therefore, the invasion of a liquid vapor and the like between the periphery of the inner vessel 12 and the inner circumferential surface of the outer vessel 13 is prevented and the corrosion of the outer vessel 13 is also prevented. A second O ring 16 is interposed between the cover 14 and the outer vessel 13 outside in the radial direction of the first O ring 15. Therefore, an airtightness is achieved surely. Then, a pressure vessel can improve its wear resistance and be used for a long term.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a pressure vessel. More specifically, the pressure of a storage space is changed from a negative pressure to a high pressure, and the temperature is raised to a corrosion resistance test of a test piece. A pressure vessel preferably implemented for

[0002]

Containers, such as absorbers and regenerators of absorption refrigerators, come into contact with the absorbing liquid, which is LiBr, and therefore the corrosion resistance of these containers must be excellent and the corrosion resistance of the material of the container. It is necessary to carry out a test, and for this corrosion resistance test, it is necessary to carry out a corrosion resistance test on the test piece under the same conditions as the operating conditions of the absorption chiller.

In a typical prior art, a coating layer of Teflon (trade name) is formed inside a container called an autoclave to prevent corrosion of the pressure container due to the liquid in which the test piece is dipped. A cross section of part of this prior art is shown in FIG. Reference numeral 1 indicates a wall of the pressure vessel, which is made of metal and has a thin coating layer 2 of Teflon adhered to the inner surface thereof.

In such prior art, liquid vapor penetrates through the thin cover layer 2 between the surface 3 of the wall 1 and the cover layer 2, and in this state the temperature drops, which is indicated by reference numeral 4. As described above, for example, water or the like is condensed, which causes a phenomenon called a blister, and the coating layer 2 is separated from the surface 3 of the wall 1. When the bottom of the pressure vessel 1 is deep, pinholes are often generated in the coating layer 2 formed by adhering to the entire inner wall of the pressure vessel 1. Therefore, liquid can be transferred to the wall 1 through the pinholes. It may penetrate between the surface 3 and the coating layer 2.

In order to solve this problem, in the prior art shown in FIG. 5, an inner container 5 made of Teflon or glass is inserted into the pressure container 1, and the test piece is immersed in the inner container 5. The liquid 6 is stored. The container 1 is hermetically closed by the lid 7. The container 1 is made of, for example, stainless steel.

In the prior art shown in FIG. 5 as described above,
The saturated vapor of the liquid 6 during the corrosion resistance test enters the slight space 8 between the inner surface of the container 1 and the inner container 5 and corrodes the container 1. Further, when the temperature is lowered to room temperature or the like, the vapor existing in the small space 8 is condensed and the liquid is stored in the space 8. When the inner container 5 is made of glass, the inner container 5 may be damaged due to a difference in coefficient of thermal expansion between the container 1 and the inner container 5. When the liquid 6 is alkaline, the glass inner container 5 is eroded.

In order to make the container 1 and the lid 7 airtight, FIG.
Bolts provided with an O-ring 9 as shown in FIG. 6 and a flat gasket or flat packing 10 as shown in FIG. It is tightened with a combination of nut and nut.

Such an O-ring 9 or flat packing 1
In the seal structure using 0, it is necessary to pay attention to the partial tightening by the combination of the bolt and the nut, and there is a problem that the work management is difficult. When the flat packing 10 is particularly made of metal, the container 1 that abuts the flat packing 10
If the seating surface of 1 or the surface of the lid 7 that comes into contact with the flat packing 10 is damaged, the sealing performance will be poor, and it will be necessary to re-cut the surface that comes into contact with the flat packing 10. Further, in this prior art, the container 1 and the lid 7 are made of metal such as stainless steel as described above, and thus when the temperature of the whole is increased,
There is a problem that the O-ring 9 and the flat packing 10 are softened and deformed or slipped, so that the sealing function is deteriorated.

[0009]

SUMMARY OF THE INVENTION An object of the present invention is to provide a pressure vessel which has excellent durability and is easy to maintain.

[0010]

SUMMARY OF THE INVENTION The present invention is directed to a synthetic resin inner container having an outward flange, a metal outer container for accommodating the inner container and having a step near the open end, and opening and closing the outer container. A metal lid having a synthetic resin coating layer formed on the surface facing the storage space of the inner container and the outward flange, and the metal lid interposed between the outward flange of the inner container and the step of the outer container. A pressure vessel comprising a first O-ring and a second O-ring interposed between the lid and the outer vessel radially outward of the first O-ring.

Further, the present invention is characterized in that a packing is interposed between the outward flange of the inner container and the cover layer of the lid.

[0012]

According to the present invention, for example, when performing a corrosion resistance test of a test piece, a liquid such as LiBr which is an absorption liquid of an absorption refrigerator is stored in an inner container made of synthetic resin, and the liquid is stored in the liquid or in the liquid. The test piece is arranged in the upper gas phase portion, and the first O-ring is interposed between the outward flange of the inner container and the step of the outer container. During this test, the longitudinal dimension of the synthetic resin inner container expanded from the outer container due to the temperature rise, and the outward flange and the cover layer of the lid were adhered with a uniform force across the flat packing. Therefore, leakage of liquid and vapor in the inner container can be reliably prevented. Further, the expanded outward flange and the synthetic resin inner container compress the first O-ring between the outward flange and the step to improve airtightness. In this way, liquid vapor is prevented from entering the gap between the inner surface of the outer container and the outer surface of the inner container.
This can prevent corrosion of the outer metal container.
Further, it is possible to prevent the liquid or the vapor thereof from entering between the metal lid and the synthetic resin coating layer, and prevent the metal lid from being corroded.

The metal lid is provided with a synthetic resin coating layer on the surface facing the storage space of the inner container and the outward flange, which prevents the lid from corroding as described above.

Further, a second O-ring is interposed between the lid and the outer container radially outward of the first O-ring,
As a result, even if the airtightness between the outward flange of the inner container and the cover layer of the lid is reduced, the vapor of the liquid is prevented from being diffused to the outside and the air from the outside is prevented from entering. The property is improved.

[0015]

1 is a sectional view of a pressure vessel 11 according to an embodiment of the present invention. This pressure container 11 basically has an inner container 12, an outer container 13 in which the inner container 12 is housed, and a lid 14 for opening and closing the outer container 13, and in order to achieve airtightness, It has one O-ring 15 and a second O-ring 16. Such a pressure vessel 11 can be heated by an electric heater 17 surrounding the outer vessel 13 as shown in FIG. 2, and the vicinity of its lid 14 is covered with a heat insulating material 18 to prevent heat radiation. .. The inner container 12 has an inner container body 19 and an outward flange 20 formed on the upper end portion thereof, and is made of a synthetic resin, for example, a material such as polytetrafluoroethylene (abbreviated as PTFE). Outer container 13
Is made of metal such as stainless steel SUS316 or SUS304. The outer container 13 has an outer container body 21 and an outward flange 22, and the inner container 12 is housed in the outer container body 21. The lid 14 is made of metal and is made of stainless steel SUS3 like the outer container 13 described above.
16 or SUS304 or the like, which closes the outer container 13 so as to be openable and closable, and is tightened by a bolt 23 and a nut 24. Reference numeral 25 indicates a spring washer.

FIG. 3 is an enlarged sectional view of the vicinity of the first O-ring 15. A step 26 is formed near the open end of the outer container 13. A coating layer 28 is adhered and formed on the surface of the metallic lid 14 that faces the storage space 27 of the inner container 12 and the outward flange 20. The coating layer 28 is made of, for example, polytetrafluoroethylene or the like, and prevents the lid 14 from corrosion. A coating layer 30 is formed on the entire inner peripheral surface of the space 29 in which the inner container 12 of the outer container 13 is housed.
The coating layer 30 is made of a synthetic resin such as polytetrafluoroethylene and prevents the outer container 13 from corroding. Inner container 1
The first O-ring 15 is interposed between the outward flange 20 of No. 2 and the portion 30 a of the coating layer 30 on the step 26 of the outer container 13. A flat packing 31 which is a flat gasket is provided between the outward flange 20 and the covering layer 28 of the lid 14.
Is intervened. This flat packing 31 is formed flat,
It is ring-shaped.

The lid 1 is provided radially outward of the first O-ring 15.
A second O-ring 16 fitted into the annular recess 32 of the outer container 13 is interposed between the outer container 4 and the outer container 13.
The first O-ring 15, the second O-ring 16, and the flat packing 31 are made of elastic material such as rubber. By the flat packing 31 coming into contact with the coating layer 28, airtightness between the outward flange 20 and the coating layer 28 is achieved regardless of the fine irregularities of the coating layer 28. The coating layers 28 and 30 are formed by painting or the like.

The linear expansion coefficient of polytetrafluoroethylene is 10 × 10 ^-5 / ° C., and the stainless steel SUS316 is used.
And the coefficient of linear expansion of SUS304 is 16.7 × 10 ^-6 /
℃. Therefore, when the temperature is raised during the test, the inner container 12 thermally expands and the inner container 12
However, by expanding in the vertical direction in FIG. 3, the upper surface 20a of the outward flange 20 is further brought into close contact with the coating layer 28 and the lid 14, thereby improving the airtightness, and the outward flange. The first O-ring 15 is brought into close contact between the lower surface 20b of 20 and the portion 30a of the coating layer 30 to further improve the airtightness.

A gap d1 between the outer peripheral surface of the inner container 12 and the inner peripheral surface of the coating layer 30 formed on the outer container 13 (see FIG. 3).
Is set to, for example, 1 mm, and this space d1 is similarly formed in the bottom portions of the inner container 12 and the outer container 13. Therefore, even when the inner container 12 and the outer container 13 are heated and raised from room temperature to 200 ° C., for example, by the electric heater 17, the inner container 1 and the outer container 13 are heated due to the difference in linear expansion coefficient between the materials.
The contact between the inner container body 19 of No. 2 and the coating layer 30 formed on the inner peripheral surface of the outer container 13 is prevented, so that the inner container 12
It prevents deformation and damage of the.

Outer flange 20 and lid 14 of inner container 12
Since the flat packing 31 is interposed between the flat packing 31 and the covering layer 28 of the inner container 12, the upper surface 20 of the outward flange 20 of the inner container 12
The airtightness is ensured even if there are irregularities in the inner container 12 when molding the inner container 12. The flat packing 31 is in contact with the outer peripheral end 28a of the covering layer 28 and the lower surface 14a of the lid 14 on which the covering layer 28 is not formed, so that the air tightness between the flat packing 31 and the covering layer 28 is achieved. At the same time, the airtightness between the flat packing 31 and the lower surface 14a of the lid 14 is achieved, and vapor or liquid may enter between the coating layer 28 and the lid 14 from the vicinity of the end 28a of the coating layer 28. It is prevented. Further, since the liquid or the vapor thereof is prevented from entering the space 29 as described above, the vapor penetrates between the coating layer 30 and the inner peripheral surface of the outer container 13 through the coating layer 30. This prevents the coating layer 30 from peeling off and prevents the blister phenomenon from occurring.

Further, by providing the second O-ring 16, even if the airtightness of the flat packing 31 is lowered, the airtightness of the storage space 27 of the inner container 12 is not lowered.

As described above, the coating layer 30 is formed on the inner peripheral surface of the outer container 13, and if the bottom of the outer container 13 becomes deeper, pinholes tend to occur in the coating layer 30. In the present invention, since the outer container 13 is provided with the inner container 12 having excellent corrosion resistance, and the first O-ring 15 and the flat packing 31 are further provided,
Even if there are pinholes in the coating layer 30, it is possible to prevent liquid or vapor from entering between the coating layer 30 and the inner peripheral surface of the outer container 13 through the pinholes. There is no risk that the 30 will peel off from the outer container 13. The lid 14 is provided with a pressure gauge 34 and a safety valve 35.

According to an experiment conducted by the inventor of the present invention, a tube 3 that stores lithium chloride LiCl in the inner container 12 and is provided on the lid 14
4 and the open / close valve 35 to change the negative pressure from −760 mmHg to high pressure 3 kg / cm ² G, and use the electric heater 17 to bring the temperature to room temperature to 185 ° C. It was confirmed that when the corrosion resistance test of (1) was conducted for half a year, the pressure vessel 11 according to the present invention maintained the airtightness and no peeling of the coating layers 28, 30 was observed.

[0024]

As described above, according to the present invention, the metal lid is provided with the synthetic resin coating layer on the surface facing the accommodation space of the inner container and the outward flange of the inner container. ,
Therefore, the lid is prevented from being corroded by, for example, a corrosive liquid stored in the synthetic resin inner container, and the first flange is provided between the outward flange of the inner container and the metal outer container. Since the O-ring is interposed, liquid vapor or the like is prevented from entering between the outer peripheral surface of the inner container and the inner peripheral surface of the outer container, and thus the outer container is corroded. It is prevented. A second O-ring is interposed radially outward of the first O-ring between the lid and the outer container, so that airtightness is achieved even more reliably.
Thus, the pressure vessel of the present invention has improved corrosion resistance and can be used for a long period of time.

[Brief description of drawings]

FIG. 1 is a sectional view of a pressure vessel 11 according to an embodiment of the present invention.

FIG. 2 is a cross-sectional view showing a state in which an electric heater 17 and a heat insulating material 18 are provided in relation to the pressure vessel 11.

FIG. 3 is an enlarged cross-sectional view near a first O-ring 15.

FIG. 4 is a partial cross-sectional view of the prior art.

FIG. 5 is a cross-sectional view of another prior art.

FIG. 6 is a cross-sectional view showing another prior art O-ring 9.

FIG. 7 is a cross-sectional view showing still another prior art flat packing 10.

[Explanation of symbols]

 11 Pressure Vessel 12 Inner Vessel 13 Outer Vessel 14 Lid 15 First O-ring 16 Second O-ring 20 Outward Flange 26 Step 28, 30 Coating Layer 31 Flat Packing

Claims (2)

[Claims] 1. A synthetic resin inner container having an outward flange, a metal outer container that accommodates the inner container and has a step near the open end, and an outer container that is opened and closed to form an inner container storage space. A metal lid having a synthetic resin coating layer formed on the surface facing the outward flange; a first O-ring interposed between the outward flange of the inner container and the step of the outer container; Pressure vessel including a second O-ring interposed between the lid and the outer vessel radially outward of the O-ring. 2. The pressure vessel according to claim 1, wherein packing is interposed between the outward flange of the inner vessel and the cover layer of the lid.