JPS583159B2 - semi-membrane tank - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a semi-membrane tank that is simple in structure, has excellent strength, and has a stable structure.

With semi-membrane tanks, the rigidity of the tank itself is low, so one problem is how to maintain the tank's shape during construction or after it enters service.

In FIG. 1, 1 is a semi-membrane tank body having a tank hatch 2. In this tank body 1, in order to maintain rigidity, side walls 3 and a bottom plate (not shown) are required.

), the problem can be solved by placing a very small amount of ossicles, but it is not easy to solve the problem with the top plate 4.

This is because bones cannot be placed in the corner radius portion 5 of the tank body 1, so even if bones are placed on the top plate 4, the top plate sinks as shown in the imaginary line when the tank is lightly loaded or unloaded.

The present invention has been made in view of the above, and is characterized by a cylindrical web extending downward from a cutout hole formed in the top plate on the inner surface of the top plate of the semi-membrane tank body; A stiffening girder having a vertical web attached to the outer surface is provided, a diametrical rope fixing beam is fixed inside the lower end of the cylindrical web, and the rope fixed beam is connected to the rope fixing beam. The main body is suspended from a hull structural member, and an elastic plate and a joist are interposed between the main body top plate and the hull structural member.

Examples thereof will be described below based on the drawings.

In FIG. 2, 6 is a semi-membrane tank main body, 7 is a top plate thereof, and 8 is a stiffening girder arranged on the inner surface of the top plate 7 in a grid pattern.

The semi-membrane tank according to the present invention is constructed by connecting one end of a cable to the stiffening girder 8 and suspending the other end of the cable from a hull structural member.

Note that 9 is a tank hatch. As a chorda, the axial direction (
For example, wire ropes, rods, chains, etc. can be used on the tensile side), and a top structure such as an inner deck plate can be used as the hull structural member. .

Note that A-T indicates the hanging position.

The specific hanging structure will be explained below based on FIGS. 3 to 9.

In FIGS. 3 and 4, 10 is a hull structural member consisting of a deck girder structure or ribs 11, and an internal deck 12. Between the inner deck 12 and the top plate 7 of the semi-membrane tank body 6, A heat shielding layer 13 is interposed.

A cutout hole 14 is formed in the top plate 7, and several joists 15 are provided between the inner deck 12 and the top plate 7 around the cutout hole 14, and the lower surface of the joist 15 and the top plate 7 are provided. An elastic plate 16 is disposed between the upper surface of the holder and the upper surface of the holder.

On the other hand, the stiffening girder 8 includes a cylindrical web 17 extending downward from around the cutout hole 14, a web 18 extending vertically and horizontally from the outer surface of the cylindrical web 17, and fixed to the lower ends of the cylindrical web 17 and the web 18. It consists of a grid-like face material 19.

The joint portion of the face material 19 with the lower end of the cylindrical web 17 has an annular shape.

A diametrical rope fixing beam 20 is fixed inside the lower end of the cylindrical web 17. This beam 20 has the inner deck 1
The lower ends of wire ropes 21 extending from 2 are connected.

That is, the upper end of the wire rope 21 is suspended from an eye plate 23 fixed to the back surface of the inner deck 12 via an eye clamp stop 22 shown in FIG. 8, and the lower end is welded to the beam 20 via an eye clamp stop 24 (25). It is connected to a stopper 26 having a shape shown in FIG.

Welding between the beam 20 and the stopper 26 can be carried out through the hollow part in the annular part of the face plate 19. After welding 25 of both, the face plate 27 is applied to the hollow part, and one side welding 28 is performed. The liquid tightness of the tank is ensured.

By suspending the top plate 7 of the tank body 6 by the stiffening girder 8 in this way, it is possible to effectively prevent the top plate 7 from sinking.

However, when the top plate 7 undergoes thermal contraction, the wire rope 2
The lower end of the eye plate 1 is displaced along an arcuate locus centered on the eye plate 23, as shown by the imaginary line in FIG.

Therefore, the lower end of the wire rope 21, that is, the stopper 26 moves upward by υ.

In this case, the displacement υ is absorbed by the elastic plate 16, and the joist 1
5 can be easily prevented from being applied with unreasonable force.

Further, instead of providing the elastic plate 16, a clearance may be provided in advance between the lower surface of the joist 15 and the upper surface of the top plate 7.

Providing the elastic plate 16 or clearance in this way is recommended when the tank length is long or when the wire rope length (
11) is extremely short and the lateral movement h of the stopper 26 is relatively large compared to l, the compressive force acting on the joist 15 and the tensile force acting on the wire rope 21 may be This is extremely advantageous in cases where the above cannot be ignored.
However, when l is sufficiently larger than h and υ is small, no problem arises even if the joists 30 and the top plate 7 are brought into contact with each other, as shown in FIG.

As mentioned above, various types of cords can be used, but in the case of FIG. 5, a chain 31 is used.

In this case, the upper end of the chain 31 may be directly connected to the eye plate 23, or may be connected via a shirtcle (not shown).

Additionally, one or more rondos (not shown).

) may be used. Figure 7 shows an inverted U on the rope fixing beam 32A.
The figure-shaped connector 32 is shown welded and connected to the eye clamp 24, and FIG. 9 is a perspective view of the alloy socket stopper 33'.

The types of connecting fittings and cables shown in FIGS. 6 to 9 should be appropriately selected to have excellent strength.

As is clear from the above explanation, according to the present invention, the length irregularities of the hanging ropes are fixed at the time of construction, that is, in the above embodiment, the welding of the fasteners 26 to the rope fixing beams 20. The suspension position can also be set with high precision because it can be easily corrected (absorbed) at times, and the cutout hole in the part where the rope connected to the stiffening girder penetrates the top plate of the tank body can be enlarged. Therefore, it is possible to provide a semi-membrane tank that is extremely easy to work with, has high strength, is stable, and has a simple structure.

In addition, the strength can be easily and reliably estimated, and the joist structure around the suspension structure does not require a complicated joist structure, which is extremely beneficial.

Furthermore, upward displacement due to thermal contraction occurring in the top plate of the tank body is absorbed by the elastic plate, so that no undue force is applied to the joists.

[Brief explanation of the drawing]

Fig. 1 is a longitudinal sectional side view showing the essential parts of a conventional semi-membrane tank, Figs. 2 to 9 show embodiments of the present invention, Fig. 2 is a plan view, and Fig. 3 is a 4 is a longitudinal sectional side view of the main part, FIG. 4 is a view taken along the line A-A in FIG. 3, FIG. 5 is a longitudinal sectional side view of the main part of a modified example, FIG. FIG. 8 is a side view of a main part showing a modification of the connection structure between the metal fittings 26 and the cable body; FIG. 8 is a perspective view of the eye clamp stopper 22;
FIG. 9 is a perspective view of the alloy socket stopper 33, and FIG. 10 is an explanatory view showing the swing locus of the wire rope 21 due to thermal contraction of the tank main plate. 6...Semi-membrane tank body, 7...
... Top plate, 8 ... Stiffening girder, 10 ... Hull structural member, 14 ... Cutout hole, 15 ...
...joist, 16...elastic board, 17...
・Cylindrical web, 18... Web, 20...
...Rope fixing beam, 21...Wire rope,
23... Eye plate, 26... Fastener, 31... Chain.

Claims (1)

[Claims] 1 A stiffening girder having a cylindrical web extending downward from a cutout hole formed in the top plate and a vertical web attached to the outer surface of the cylindrical web is provided on the inner surface side of the top plate of the semi-membrane tank body, A diametrical rope fixing beam is fixed inside the lower end of the web, and the main body is suspended from the hull structural member by the rope connected to the rope fixing beam, and the main body top plate and the hull structural member are connected to each other. A semi-membrane tank characterized by having an elastic plate and a joist interposed between the tanks.