JPH0741671Y2 - Explosive hatch structure - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial application] The present invention relates to an explosion hatch structure.

[Conventional technology]

In order to prevent the tank from exploding due to an abnormal rise in tank internal pressure, the explosive hatch automatically ruptures when the internal pressure rises above a set value and explosive gas in the tank is released all at once into the atmosphere. It is used as a safety valve to release, and a large-capacity tank has an explosive hatch that is as large as a small cargo hatch.

For example, as an explosive hatch structure to be installed in an offshore crude oil storage tank, a conventional hatch hatch structure having substantially the same structure as a cargo hatch cover of a cargo ship has been used. A structure for tightening is adopted, and FIG. 2 is a perspective view and FIG.
As shown in the partial cross-sectional view of the drawing, a hatched cover 01 is provided around a lower groove 02 on the lower surface of the hatch cover 01, and a sponge gasket 03 having a cross-sectional dimension of a thickness of about 30 mm and a width of about 70 mm is fitted to the hatched cover 01. It is known that an upward seal bar 05, which is circumferentially projected and abuts, comes into contact. Here 05a is hatching combing.

In such a structure, the contact pressure with the upward seal bar 05 of the gasket 03 is adjusted by selecting the thickness of the liner 06 and tightening the breaking bolt 07.

However, such a structure has the following drawbacks.

(1) To ensure the airtightness of the detonation hatch cover 01,
The gasket 03 and the seal bar 05 need to come into contact with each other at a predetermined pressure, but since the explosion hatch cover 01 and the combing top plate 04 are deformed at the time of production, the explosion hatch cover 01
It is difficult to obtain uniform contact pressure over the whole, that is, uniform airtightness.

(2) As a measure against the above (1), there is also a means for adjusting the depth of the skirt 08 of the explosion hatch cover 01 to the site, but this is not preferable because it requires a lot of man-hours.

(3) Since the contact pressure of the gasket 03 decreases with the lapse of time, the airtightness also decreases, and therefore the safety cannot be said to be sufficient.

(4) Since the explosion hatch cover 01 moves slightly in the vertical direction due to the change in the tank internal pressure, the contact pressure of the gasket 03 changes, and therefore the airtightness changes, and the safety cannot be said to be sufficient.

(5) When a gas leak locally occurs from the gasket 03, the gasket 03 cannot be repaired from the outside in the same state, which is insufficient for safety.

[Problems to be solved by the device]

The present invention has been proposed in view of such circumstances,
An explosive hatch structure with excellent economic efficiency and safety that can be repaired from the outside without being affected by deformation during manufacturing, aging, tank pressure changes, and local gas leaks. The purpose is to provide.

[Means for Solving the Problems]

Therefore, the present invention is an explosive hatch structure in which the explosive hatch is hermetically closed by an explosive hatch cover through a plurality of breaking bolts, and a groove structure projectingly provided around the top plate of the hatch coaming is provided. And a deformable seal material that is fluidly applied in the groove structure and exhibits adhesive force after curing, an upper end protruding along the outer peripheral lower surface of the hatch cover, and a lower end portion embedded in the seal material. It is equipped with a downward facing seal bar.

[Action]

Since the groove structure is formed facing upward, the sealing material to be applied in a fluid state can be filled by the downward work, thus facilitating the work. Further, since the sealing material has adhesiveness and deformability, the groove structure and the contactability with the downward seal bar are improved. Furthermore, since the adhesive strength of the seal material is large, the gap between the groove structure and the seal bar can be determined with a margin. Since the airtightness is maintained by the adhesiveness of the sealing material and the like, airtightness management by adjusting the tightening pressure of the breaking bolt is not necessary. Further, when the uncured material is applied on the cured material on the cured material, the both are fused and integrated, so that the material can be repaired from the outside as it is.

〔Example〕

An embodiment in which the present invention is applied to an offshore crude oil storage tank will be described with reference to the drawings.
~ The same reference numerals as in Fig. 3 denote the same members as in Fig. 3, respectively, and 1 denotes a groove formed around the outer circumference of the combing top plate 04,
2 is a sealer filled in the groove 1 to a depth d, which has fluidity during application, has a tensile strength and adhesive strength after curing of 5 to 10 kg / cm ² and has an elongation of 100% or more.

3 is a downward seal bar whose upper end is welded along the outer circumference of the lower surface of the explosive hatch cover 01 and whose lower end is embedded in the sealer 2. The spacing a, b between the combing top plate 04 and the groove member 4 is about 10 mm, respectively. is there. Reference numeral 5 is a liner having a constant thickness that supports the weight of the explosion hatch cover 01 through the skirt 08, and 6 is a plurality of break bolts for fastening the explosion hatch cover 01 to the hatch combing 05a side.

In such a structure, in order to mount the explosive hatch cover 01 on the combing top plate 04, first, the sealer 2 is placed in the groove 1.
To the depth d, before the sealer 2 hardens, the downward facing seal bar 3 of the explosive hatch cover 01 is fitted into the groove 1, and then the explosive hatch cover 01 is hatched with the breaking bolt 6 05a. Tighten to.

Further, explosion tank pressure generally release the so 0.3~0.4kg / cm ^2, tensile strength and adhesive strength of 5 to 10 kg / cm ² Sealer 2
In this embodiment, the filling depth d of the sealer 2 is 30
In addition, the plane dimensions of the explosive hatch cover 01 is a square with a maximum side of about 4.5 m, and the machining error is ± 3 mm.
Since it is about the same, the dimension of the interval a is about 10 mm. In addition, the vertical movement of the explosion hatch cover 01 due to changes in internal pressure is maximum.
Since it is about 2 mm, the distance b should be about 10 mm.

Further, as the sealer 2, a sealer having a characteristic that when the uncured state is applied on the cured state, the both are fused and integrated is used.

With such a structure, the following effects can be obtained.

(1) Since the groove is formed upward, it is easy to fill the sealer, which is constructed in a fluid state, so that the number of steps is reduced.

(2) Since the sealer has adhesiveness and deformability,
Good contact with the groove and the downward seal bar, thus improving air tightness.

(3) Since the adhesive strength of the sealer is large, the gap between the groove and the seal bar can be determined with a margin, and therefore adjustment of manufacturing error of the hatch cover or the like becomes unnecessary.

(4) Since the airtightness is maintained by the adhesiveness of the sealer and the like, the airtightness management by adjusting the tightening force of the breaking bolt becomes unnecessary, and therefore the number of steps is reduced.

(5) If a sealer is applied on top of a hardened one and an uncured one is fused and integrated, so if a local gas leak occurs from the sealer, it should be repaired from the outside as it is. And thus improve safety.

(6) The structure of the present invention can also be used as a safety device for a coal storage.

[Effect of device]

In short, according to the present invention, in the explosive hatch structure in which the explosive hatch is hermetically closed by the explosive hatch cover via the complicated breaking bolt, the groove formed in a protruding manner on the top plate of the hatch coaming. A structure, a deformable seal material that is fluidly applied in the groove structure and exerts adhesive force after curing, an upper end protruding along the outer peripheral lower surface of the hatch cover, and a lower end portion embedded in the seal material. By installing the downward facing seal bar, it is possible to repair local gas leakage from the outside without being affected by deformation during manufacturing, aging, tank internal pressure, etc. The present invention is extremely useful industrially because it provides an explosive hatch structure excellent in safety and safety.

[Brief description of drawings]

FIG. 1 is a partial cross-sectional view showing an embodiment in which the present invention is applied to an offshore crude oil storage tank. FIG. 2 is a perspective view showing a known explosive hatch structure of an offshore crude oil storage tank, and FIG. 3 is a transverse sectional view taken along line III-III of FIG. 1 ... Groove, 2 ... Sealer, 3 ... Downward seal bar,
4 ... Groove member, 5 ... Liner, 6 ... Break bolt, 01
…… Explosion hatch cover, 04 …… Coming top plate, 05a…
... hatch combing, 08 ... skirt,

Claims (1)

[Scope of utility model registration request] 1. An explosive hatch structure in which the explosive hatch is hermetically closed by an explosive hatch cover via a plurality of breaking bolts, and a groove structure projectingly provided around a top plate of the hatch coaming. , A deformable sealing material that is fluidly applied in the groove structure and exhibits adhesive force after curing, and a downwardly facing upper end protruding along the outer peripheral lower surface of the hatch cover and a lower end portion embedded in the sealing material Explosive hatch structure characterized by having a seal bar.