JPS5985076A - Assembling of double shelled spherical tank - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for assembling a double-shelled low temperature liquefied gas storage m-spherical tank.

A general method of assembling a conventional double-shelled spherical tank will be explained with reference to the completed diagram in FIG.

That is, using the conventional assembly method, the outer tank support (1) is erected on the foundation (6), the equatorial part of the outer tank (2) and the lower temperate zone of the outer tank are constructed on top of it, and then The inner tank (3) 2 is assembled at the bottom of the outer surface of the inner tank via a plurality of hanging rods (5) or wire lobes engaged with brackets (4) protruding from the inner wall of the outer tank. ) was suspended.

In this conventional structure, the inner tank (3) is the outer tank (2).
Because of the structure of suspending and holding the tank, it was necessary to assemble the outer tank (2), which serves as the frame for the inner tank (3), in advance before assembling the inner tank (3).

In that case, when assembling the inner tank (3), the gap between the outer tank (2) and the outer tank (2) is very narrow at 600 meters or 700 meters, so when workers are working in that gap, there are many It was difficult. In particularly high-risk pressure vessels such as spherical tanks, it is a major requirement to thoroughly inspect both the inside and outside of the parts after welding to increase joint efficiency and ensure the safety of the vessel. Therefore, the narrow working space for welding, inspection, etc. was an assembly problem.In addition, in the conventional method, the outer tank (2) needed to function as a frame to hold the inner tank (3). Therefore, the outer tank (2) had to have a strong structure to maintain its rigidity, which required a large plate thickness, and required sufficient welding and inspection.

In addition, in order to secure the above-mentioned work space, it is necessary to construct the outer tank at a distance of about 600 to 700 mm from the inner tank (3). This has the drawback of requiring a huge amount of parts vehicles.

Furthermore, this conventional method requires a complicated support structure to accommodate the thermal expansion and contraction of internal components such as the inner tank (3) and the suspension rod (5), as well as the vibrational movements caused by earthquakes. However, the number of suspension rods (5) becomes large.

In addition, a reinforcing ring (7) is also required for the outer tank (2) that receives the cart of the inner tank (3), and a support ring (1) is also required from the outer tank (2).
), it was also necessary to provide a large number of reinforcing ribs to transmit the load, making the support structure complicated.

In addition, the inner tank (3) has a rod (5) extending from the outer tank wall.
Because it has a structure that allows it to be suspended vertically by means such as the above, and does not have a horizontal restraint function, there is a high risk that the inner tank (3) will shake significantly in the event of an earthquake, making the entire tank unstable. There were also serious flaws.

The present invention was developed in view of these circumstances, and it eliminates the drawbacks of conventional construction methods, has high assembly accuracy, is excellent in assembly workability, and eliminates the instability of the behavior of the inner tank during earthquakes. This provides a method for constructing a stable spherical tank with a double shell structure.

The gist is that the outer tank support is fixed to the same base plate concentrically outside the inner tank support,
Furthermore, a cylindrical upper column that supports the outer tank equatorial plate is fitted into the support column in advance so that it can move up and down, and is erected on the foundation of the composite support 2, and all the inner tanks are assembled. After welding and subsequently completing all inspections such as welding inspection and pressure resistance test, the upper column that had been lowered to the base of the column is lifted and fixed at a predetermined position 1, and then the penetration part of the inner tank column is The outer tank support walkway board, which is divided into upper and lower parts with the pillar as the boundary, is sandwiched and joined to the top of the column, and the outer tank support walkway board is assembled in the same manner. This is a method for assembling a spherical tank with a double shell structure, in which an outer tank equatorial plate is assembled between the columns to form an integral outer tank equatorial section, and then upper and lower temperate zone plates and polar plates are assembled.

Next, details of embodiments of the present invention will be described with reference to the drawings.

FIG. 2 is a partially broken, completed view of a double-shelled spherical tank assembled by the construction method of the present invention.

The assembly procedure according to the construction method of the present invention will be explained with reference to the drawings from FIG. 2 and FIG. 3 onwards.

Fig. 3 is a diagram showing the situation when assembling the outer tank support, in which the outer tank support (to) is concentrically fixed to the common base plate (to) on the outside of the inner tank support, and The cylindrical upper column (2) that supports the outer tank equatorial plate (Thailand) on the outside is fitted into the column in advance so that it can move up and down, and the three cylindrical bodies are assembled. Composite strut (
Place the tank (to) on the foundation (b) and assemble all the inner tanks (to).

It should be noted that if the above-mentioned composite strut (to) is manufactured at a factory equipped with processing equipment, it is possible to manufacture the composite strut with higher precision. An upper gusset plate (c) and a lower gusset plate are fixed in advance to the upper and lower parts of the support column to which the reinforcement rod Q is attached.

The assembly procedure for the inner tank (to) is the same as the assembly method for conventional single-shell spherical tanks. First, temporarily assemble the equatorial plate, upper and lower temperate plates, and upper and lower polar plates, and check the dimensions of each part, the alignment of the joints, etc. measure,
After confirming that it is within the allowable value, weld the inside and outside surfaces, and then complete various welding inspections and pressure resistance tests.

At this stage of assembling the inner tank, the outer tank plate is not attached at all, and then preparations for assembling the outer tank begin.

FIG. 4 is a diagram illustrating a state in which the upper column (end) that receives the footpath board 04)Cf3 of the outer tank support is lifted and fixed at a predetermined height l.

That is, in FIG. 3, the upper column (to) which has been lowered to the lower part of the outer tank support (2) is lifted up at a predetermined height 1, and the lower end of the column is suspended through a cone shell 61 formed into a conical shape. FIG. 4 shows the state in which it is joined to the upper end of the outer tank support column (2). Cone shell lI3 is
Split it into two pieces in advance and tie them together around the support.

In addition, a guide groove @4 is provided in the axial direction on the side of the upper column.

The upper gusset plate 6D is fitted here.
It has a mechanism 2 for accurately guiding the column to a predetermined position.

Assemble all the pillars in the same manner.

Next, assemble the equatorial plate for the outer tank support.

Outer tank support section sidewalk board 0! ! Figures 5 and 6 show the working conditions for installing (b). .

The outer tank support footpath board is cut out at the penetrating part of the inner tank support OD, and is divided into upper and lower parts around the support. It consists of an equatorial plate (material) that is lifted from below and connected to the upper edge opening of the upper column (to). Next, as shown in the sixth factor,
Upper equatorial plate 0! Hang J from the outside of the column (to), insert it so as to sandwich the top of the upper column (to), join both equatorial plate materials (b) and (f), and form a single outer tank lower pole plate. To construct. In the same way, after forming the lower electrode plates of each outer tank, the equatorial plates (c) between each column are successively suspended, inspected for dimensions around the entire circumference, and then welded to form a single external equatorial section. Build. Equatorial plate between the supports U! If l is constructed from two or more materials, several materials may be joined in advance on the ground.

Next, assemble the outer tank upper ■ζ wet strip plate ring and the outer tank lower electrode plate θη, and then assemble the outer tank upper electrode plate (!1) and the outer tank lower electrode plate i19 to complete the entire inner and outer tank. It is a construction method. (Fig. 2) According to the heather construction method, the outer tank [noto inner tank]
(to) are supported separately by the outer tank strut (to) and the inner tank strut H, and the structure is such that they are not in direct contact with each other, so the stress due to thermal expansion and contraction of the inner tank is rarely transmitted directly to outside M (goods). In other words, the inner and outer tank supports (2
) has a free-end structure, and even if a bending moment is applied to the support when the inner tank (to) thermally expands or contracts, the inner tank support oD will only be displaced independently and the outer tank support (To)
is not displaced.

In other words, the deformation resistance of the struts is small and driving is safe.

Moreover, since the outer tank part is not connected immediately to the inner tank support part, there is an advantage that the amount of cold heat transferred from the inner tank to the outer tank is small.

Furthermore, according to this structure, since the inner tank Cal+ is directly supported by a strong support, the swinging of the inner tank (to) during an earthquake can be reliably restrained, thereby improving safety.

In addition, the outer tank il+1 does not need to have the function of rigidly suspending the inner tank (to), but simply serves as an exterior material that supports the heat insulation layer (to), so the strength requirements are considerably reduced. Therefore, the exterior material is made of a relatively thin steel plate made of ordinary steel, and the ffi unevenness of the parts can be reduced.

Furthermore, this method allows the composite struts to be pre-assembled in a factory in one piece, which has the advantage of increasing machining accuracy and reducing the cost of transporting materials from the factory to the construction site.

As is clear from the above description, according to the present invention, the assembly work of the double-shell spherical tank is simplified, and the stress acting on the support material is the most severe during filling with low-temperature liquefied gas and during release. Or, even during an earthquake, the acting stress can be alleviated, and it is possible to reduce the number of parts used in the outer tank, reducing construction GL.
Operation σ] This can greatly contribute to safety.

[Brief explanation of the drawing]

FIG. 1 is a partially cutaway view of a completed double-shelled spherical tank constructed using the conventional assembly method. FIG. 2 is a partially cut away completed view of a double shell spherical tank constructed by the assembly method of the present invention. Figures 3 to 6 are diagrams showing an embodiment of the construction method of the present invention. Fig. 3 is a perspective view showing the situation when the struts are assembled;
The figure is a perspective view showing a state in which the upper column (to) that receives the outer tank lower pole plates (b) (to) is lifted to a predetermined height and fixed, and FIG. )
Fig. 6 is a perspective view showing how the upper equatorial plate (to) of the outer tank support section is lifted up and suspended from the top of the upper column (to), as in Figure 6 (Fig. 6). It is a perspective view showing the situation in which the tank is inserted. 4+...e...Bracket (5)...
...... Hanging rod (6) ---116, exposure, foundation (7) ...... Reinforcement ring <111 ......... Inside Tank…support (to)…
...... Outer tank rain support (to) a - - - Monk ...
Base plate (7) Ant 11 @ Musical accompaniment $ Ceremonial accompaniment achha column (9) ...... Foundation (2) ...... Inner tank (to)・・・・・・・・・Composite strut frame・L・-eArt・@-・Bracing rod@◇・Rei・
Reference...ee-e Upper gusset plate (6)...
−・・Lower gusset plate C1・−・・−IIa
e＠Kashi cone shell＠4・・・・・・・・・Guiding groove (c)・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・
......Outer tank top plate θη......Outer tank bottom plate (to)...Outer tank decoy... ...Outer tank lower electrode plate (to) ...Heat insulation layer (51) ......Outer tank upper electrode plate Patent applicant Ishii Iron Works Co., Ltd.

Claims (1)

[Claims] An outer tank support is fixed to the same base plate concentrically outside the inner tank m support, and a cylindrical upper column that supports an external equatorial plate concentrically outside of the support is installed in advance. The composite strut is inserted into the base so that it can move up and down, and the composite strut is erected on the foundation, and all the inner tanks are assembled and welded.After welding inspection and pressure resistance test are performed, the composite strut is lowered to the base of the strut. After lifting and fixing the upper column at foot position 1, cut out the penetrating part of the inner tank support and divide it into upper and lower parts using the support as the boundary. Connect and fix the boards by inserting them into the top of the upper column, assemble the walkway boards for each outer tank support column in the same manner as His Highness, and then incorporate the outer tank equatorial board between the columns to form an integrated outer tank equatorial part. 1. A method for assembling a double-shell spherical tank, which comprises forming upper and lower outer tank temperate plates and then assembling outer tank pole plates.