JP2012026541A - Safety mechanism of supply and discharge valve - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent a pressure container from exploding even though the inner pressure of the pressure container is abnormally raised.SOLUTION: In the safety structure of the supply and discharge valve in which the locking step part 9 is formed in the inner face of the supply and discharge cylinder fitting part 5 of the container body 1, the flange 13 of the supply and discharge cylinder 12 is locked to the locking step part 9, in an O-ring 20 is fitted between the locking step part 9 and the opening end 5a of the supply and discharge cylinder fitting part 5, the ring-shape channel 18 between the locking step part 9 and the O-ring 20 communicates with the inside of the container via the safety whole 23.

Description

  The present invention relates to a safety mechanism for a supply / discharge valve used in a pressure vessel such as an accumulator.

  Since the accumulator is a pressure vessel including a bladder in which high-pressure gas, for example, nitrogen gas having a set pressure of 20 MPa is enclosed, the structure must be strong and safety must be ensured. Therefore, in order to confirm the safety of the accumulator, a pressure safety test (also referred to as “destructive test”) is performed. This test is performed by applying a pressure exceeding a set pressure to the container. If the structure of the container is strong, the test ends with a result of rupture.

  In the destructive test, the container eventually ruptures, so that a bursting sound, debris scattering, and the like are generated. Therefore, it is dangerous and the working environment is also deteriorated. Therefore, facilities such as dedicated pits and measures for ensuring safety of workers are necessary. In addition, if the pressure exceeding the safety factor is applied not only during the test but also during operation of the accumulator, the container may rupture, which is dangerous.

  In view of the above circumstances, an object of the present invention is to prevent bursting even if the internal pressure of a pressure vessel rises abnormally.

  According to the present invention, a locking step portion is formed on the inner surface of the supply / discharge cylinder fitting portion of the container body, and the hook portion of the supply / discharge cylinder is locked to the locking step portion. In the safety structure of the supply / discharge valve in which the O-ring is fitted between the opening end of the exhaust tube fitting portion, the ring-shaped passage between the locking step portion and the O-ring is formed through the fluid communication hole. It is characterized by communicating with the inside of the container.

  The locking step portion of the present invention is provided with a locking inclined surface, and the engaging inclined surface of the flange portion of the supply / discharge cylinder is in surface contact with the locking inclined surface, and the fluid communication hole includes: It is a safety hole penetrating the wall portion of the supply / discharge cylinder. The locking step portion of the present invention is provided with a locking horizontal plane, and the engaging horizontal plane of the flange portion of the supply / discharge cylinder is in surface contact with the locking horizontal plane, and the O-ring is connected to the supply / discharge cylinder. The groove wall of the O-ring groove opposite to the flange portion is deformed when the O-ring receives a breaking pressure.

  The fluid communication hole according to the present invention is an outer surface groove extending from the outer peripheral surface of the flange portion of the supply / discharge cylinder to the O-ring. The outer surface groove of the present invention is an axial longitudinal groove, a spiral turning groove, or a flat surface extending in the axial direction of the supply / discharge cylinder.

  In this invention, since the ring-shaped passage between the locking step and the O-ring communicates with the inside of the container through the fluid communication hole, the inside of the container exceeds the design pressure and reaches a predetermined dangerous high pressure. Then, the fluid in the container press-fits into the ring-shaped passage between the locking step portion and the O-ring through the fluid communication hole, and strongly presses the O-ring. If it does so, an O-ring will deform | transform and a seal leak will generate | occur | produce, Therefore The pressure in the said container falls. Therefore, since the container can be prevented from rupturing, it is possible to perform a destructive test and operation of the container safely and without deteriorating the working environment.

1 is a longitudinal sectional view showing a first embodiment of the present invention. It is a principal part enlarged view of FIG. It is a longitudinal cross-sectional enlarged view which shows 2nd Embodiment of this invention, and is a figure corresponding to FIG. It is a longitudinal cross-sectional enlarged view which shows 3rd Embodiment of this invention.

A lid 3 is provided at one end of the container body 1 of the pressure vessel, for example, the accumulator Acc, and a supply / discharge valve 7 is provided at the supply / discharge cylinder fitting portion 5 at the other end.
The supply / discharge cylinder fitting portion 5 is formed in a cylindrical shape, and a locking step portion 9 is provided on the upper side of the inner peripheral surface thereof. The locking step portion 9 includes a locking inclined surface 9a that is inclined upward and outward, and the inclination angle is appropriately selected as necessary.

  The supply / discharge valve 7 includes a supply / discharge cylinder 12, a poppet valve 15 inserted into the supply / discharge cylinder 12, and a support mechanism 16 that holds the poppet valve 15 slidably. A flange 13 is provided at the tip of the supply / discharge cylinder 12. The flange portion 13 includes an engagement step portion 14 that engages with the locking step portion 9, and the lower surface of the engagement step portion 14 has an engagement inclined surface 14 a that is in surface contact with the locking inclined surface 9 a. It has become.

  A ring-shaped passage 18 is formed between the locking step portion 9 and the opening end portion 5a of the supply / discharge tube fitting portion 5. The ring-shaped passage 18 is sealed by an O-ring 20. Yes. The O-ring 20 is fitted in an O-ring groove 21 provided on the outer peripheral surface of the supply / discharge cylinder 12.

  The supply / discharge cylinder 12 is provided with a safety hole 23, and this safety hole 23 passes through a wall portion 12 a located between the engagement step portion 14 and the O-ring 20. Therefore, the ring-shaped passage 18 and the inside of the container are always in communication with each other through the safety hole 23. The position, size, shape, and the like of the safety hole 23 are appropriately selected as necessary.

  In the figure, 25 is a tightening nut for fixing the supply / discharge cylinder 12 to the supply / discharge cylinder fitting portion 5, 27 is a bladder (gas chamber) filled with nitrogen gas, 29 is an air supply valve, and 31 is a liquid chamber. , C represents the axis of the container body 1, respectively.

  Next, the operation of this embodiment will be described. During the destructive test of the accumulator or during operation, when the pressure in the container is within the set value, the fluid R in the container, for example, oil, has entered the ring-shaped passage 18 through the safety hole 23. However, since it is sealed by the O-ring 20, it does not leak out of the machine (see the right side of the axis C in FIG. 2). When the pressure in the container exceeds a set value and reaches a predetermined high pressure, that is, a high pressure that may cause destruction of the container, the collar portion 13 of the supply / discharge cylinder 12 is compressed and deformed under a large load. The flange 13 descends while sliding down on the locking inclined surface 9a.

  In this way, the supply / discharge cylinder 12 of the supply / discharge valve 7 is displaced in the direction of the axis C as a whole (see the left side of the axis C in FIG. 2). It exposes from the opening end part 5a of the fitting part 5, and an O ring seal becomes ineffective. Therefore, the high-pressure fluid R in the container is discharged out of the machine through the safety hole 23, the ring-shaped passage 18, and the O-ring 20.

  At this time, the locking inclined surface 9a and the engaging inclined surface 13a may be metal-sealed, but the safety hole 23 always communicates with the ring-shaped passage 18 even if the metal-sealed. Therefore, the high-pressure fluid R is reliably discharged out of the machine. In addition, the leaking pressure can be controlled by adjusting the inclination angle of the inclined surfaces of the locking step portion 9 and the engagement step portion 14.

A second embodiment of the present invention will be described with reference to FIG. 3. The same reference numerals as those in FIGS. 1 and 2 have the same names and functions. Differences between this embodiment and the first embodiment are as follows.
(1) In the first embodiment, the locking step and the engaging step are provided with inclined surfaces. However, in this embodiment, the locking step 39 and the engaging step 34 are used instead of the inclined surface. The horizontal planes 39a and 34a are not displaced in the axial center C direction.
(2) Although the O-ring groove is not deformed in the first embodiment, in this embodiment, the groove wall (outer wall) 21a opposite to the safety hole 23 of the O-ring 20 is formed thin, and the O-ring groove is formed. When the ring 20 receives a breaking pressure, the outer wall 21a is deformed and the O-ring seal is not effective.

  In this embodiment, during the accumulator destructive test or during operation, when the pressure in the container is within the set value, the fluid R in the container, for example, oil, passes through the safety hole 23 and passes through the ring-shaped passage. However, since it is sealed by the O-ring 20, it does not leak out of the machine (see the right side of the axis C in FIG. 3).

  When the pressure in the container exceeds a set value and reaches a predetermined high pressure, that is, a high pressure that may cause destruction of the container, the high-pressure liquid R flowing into the ring-shaped passage 18 causes the O-ring 20 to move with a large force. Press.

  Then, since the groove wall (outer wall) 21 a opposite to the safety hole 23 of the O-ring groove 21 is deformed, a part of the O-ring 20 protrudes from the O-ring groove 21. Therefore, the O-ring seal is not effective, and the high-pressure fluid R in the ring-shaped passage 18 is discharged out of the machine through the screwing portion 25a of the tightening nut 25 and the like. The leaking pressure can be controlled by adjusting the thickness of the outer wall 21a.

A third embodiment of the present invention will be described with reference to FIG. 4. The same reference numerals as those in FIGS. 1 and 2 have the same names and functions. The difference between this embodiment and the first embodiment is as follows.
In the first embodiment, the fluid communication hole is a safety hole, whereas in this embodiment, the outer surface groove extending from the outer peripheral surface of the flange portion 13 of the supply / discharge cylinder 12 to the O-ring groove 21 is used. .

  As the outer surface groove, a spiral turning groove 43 (see FIG. 4A), a longitudinal groove 44 extending in the axial direction (see FIG. 4B), or a flat surface 45 extending in the axial direction (FIG. 4C )) Is adopted, but the form thereof can be changed as needed.

  Although the embodiment of the present invention has been described with respect to an accumulator, the present invention is not limited to this and can be applied to other pressure vessels.

DESCRIPTION OF SYMBOLS 1 Container body 5 Supply / discharge cylinder fitting part 9 Locking step part 12 Supply / discharge cylinder 13 Gutter part 14 Engagement step part 18 Ring-shaped passage 20 O-ring 21 O-ring groove 23 Safety hole C Axis center

Claims (5)

A locking step portion is formed on the inner surface of the supply / discharge tube fitting portion of the container body, and the hook portion of the supply / discharge tube is locked to the locking step portion, and the locking step portion and the supply / discharge tube are fitted. In the safety structure of the supply / discharge valve in which an O-ring is fitted between the opening end of the part,
A safety mechanism for a supply / discharge valve, wherein a ring-shaped passage between the locking step and the O-ring communicates with the inside of the container through a fluid communication hole. The locking step portion is provided with a locking inclined surface,
The engaging inclined surface of the hook portion of the supply / discharge cylinder is in surface contact with the locking inclined surface,
2. The safety mechanism for a supply / discharge valve according to claim 1, wherein the fluid communication hole is a safety hole penetrating a wall portion of the supply / discharge cylinder. The locking step portion is provided with a locking horizontal surface,
The engaging horizontal surface of the hook portion of the supply / discharge cylinder is in surface contact with the locking horizontal surface,
The O-ring is fitted into an O-ring groove formed on the outer peripheral surface of the supply / discharge cylinder, and the groove wall on the opposite side of the flange portion of the O-ring groove is when the O-ring receives a breaking pressure. The safety mechanism for a supply / discharge valve according to claim 1, wherein   The safety mechanism for a supply / discharge valve according to claim 1, wherein the fluid communication hole is an outer surface groove extending from an outer peripheral surface of a flange portion of the supply / discharge cylinder to the O-ring.   5. The safety mechanism for a supply / discharge valve according to claim 4, wherein the outer groove is a longitudinal groove in the axial direction, a spiral turning groove, or a flat surface extending in the axial direction of the supply / discharge cylinder.

Images