JPH06270986A - Tank for cargo ship - Google Patents

Abstract

PURPOSE:To offer a LNG tank which is easy to manufacture, allows restriction of rise in costs and has an excellent carrying efficiency. CONSTITUTION:A tank 1 is to be mounted on a ship and is constituted of membrane materials on which corrugates are arranged longitudinally and laterally at specified intervals. The tank 1 having a rectangular plane view is divided into three sections widthwise, and at a bow side edge 1a of the tank 1, left and right side tanks 12 are tilted outward at a specified angle alpha against a central tank 11. In addition, connecting tanks 13 are arranged in gaps between the central tank 11 and the side tanks 12 and each consist of two right triangle- shaped connecting half tanks 14 and 15 which are symmetrical in shape and their sides 14a and 15b are in contact with each other.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an LNG tank mounted on an LNG transport ship, for example.

[0002]

2. Description of the Related Art Conventionally, LNG mounted on an LNG transport ship
In the membrane tank system for use, as a general rule, it was composed of a stainless steel membrane material in which wrinkles called corrugates that run vertically and horizontally at 340 mm intervals (pitch) were formed. In this way, the corrugated structure is
This is because the LNG has an extremely low temperature and absorbs the expansion and contraction of the tank itself due to temperature changes and ship deformation.

As shown in FIGS. 3 (a) to 3 (c), in this kind of tank 51, corrugates 52a and 53a of adjacent membrane materials 52 and 53 are continuous on the ridgeline thereof, and In order to easily perform the connection process between the corrugations, the crossing angle θ between the adjacent membrane materials 52 and 53 is set to 135 degrees (or 90 degrees), and the cross-sectional shape in the length direction is set to the same shape. It was 3A is a plan view of the tank, FIG. 3B is a front view of the same, and FIG. 3C is a side view of the same.

For this reason, the width of the tank 51 is uniform over the entire length, and as shown in FIG. 4, it is arranged near the bow of the hull 61, for example.
The width of the NO.1 tank 51A is adjusted to the hull width of the bow,
It was narrowed. However, since the width of the NO.1 tank 51A is adjusted to the narrow width of the bow portion and near the bow, a dead space S is created in the hull 61 near the stern side of the NO.1 tank 51A, which is extremely dangerous. However, there is a drawback that the loading efficiency becomes poor.

As a solution to such a drawback, it has been proposed that the tank 71 has a trapezoidal plan view, as shown in FIGS.

[0006]

However, as described above, when the shape of the tank in plan view is simply trapezoidal, the corrugations on the upper and lower wall surfaces of the tank horizontal portion 71a and the corrugations on the inclined wall surface of the tank chamfer portion 71b are formed. At the time of connection processing, in order to connect one corrugate, for example, the corrugated space between the inclined wall surfaces to the corrugated space between the upper and lower wall surfaces, it is necessary to match the distances, or the angle at which both wall surfaces intersect is 135 degrees (or 90 degrees).
Since there is a slight deviation from the degree), the number of manufacturing steps for the tank increases, and the number of types of heat insulating panels to be installed on the outside of the tank also increases, leading to a problem of increased cost.

[0007] Therefore, an object of the present invention is to provide a tank for a transport ship which can solve the above problems.

[0008]

In order to solve the above-mentioned problems, the tank for a transport ship according to the present invention is a tank which is mounted on a hull and is composed of a membrane material in which corrugates are arranged longitudinally and laterally at predetermined intervals. Then, the tank having a rectangular shape in plan view is divided into three in the width direction, and one of the front and rear ends of the tank is
The port side tanks on the left and right with respect to the central tank are opened outward by a predetermined angle, and the connecting tanks are placed in the gaps between the central tanks and the port side tanks.
Further, each of these connecting tank parts is composed of two connecting half tank parts in the shape of a right triangle, which are symmetrical to each other and whose hypotenuse parts are in contact with each other.

[0009]

According to the above construction, the tank is divided into three parts, and the port side tank parts on the left and right sides are opened outward at a predetermined angle with respect to the central tank part, and the tank parts are arranged in this opened gap part. Since the connecting tank part is formed by combining two right-angled triangles that are symmetrical with each other, that is, have the same apex angle, the central tank part and the port side The corrugates of the membrane material that make up the tank parts intersect at the same intervals (pitch) on the hypotenuses, and the corrugation intervals on both sides can also be the same. The angle of intersection can be made to be exactly the same as the conventional one, so it is possible to use the heat insulation panel that can be used in the conventional rectangular tank as it is. That.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to FIGS. In FIGS. 1 and 2, for example, reference numeral 1 denotes a shape change position of a hull of an LNG transport ship, that is, an LNG tank (transport ship tank) arranged at the bow portion, and as a general rule, wrinkles that run vertically and horizontally at 340 mm intervals (pitch). The corrugated gate 2 is formed of a stainless steel membrane material 3.

The front view of the tank 1 is octagonal as shown in FIGS. 1 (a) to 1 (c), and its cross-sectional shape is gradually increased from the bow side to the stern side. The width is wide. 1A is a plan view of the tank, FIG. 1B is a front view thereof, and FIG. 1C is a side view thereof. Hereinafter, the shape of the tank 1 will be described in detail.

The tank 1 has a rectangular shape in plan view divided into three in the width direction, that is, divided into a central tank portion 11 and left and right port side tank portions 12, and an end portion on the bow side. In 1a, the left and right port side tank portions 12 are not opened to the outside at a predetermined angle (α), and the gaps between these port side tank portions 12 (indicated by diagonal lines in FIG. 1 (a)) are substantially triangular. The connection tank portion 13 having a shape (correctly, a quadrangular shape) is arranged. Then, as shown in FIG. 1A, each of the connecting tank portions 13 has two right-angled triangular connecting half tank portions 14, which are symmetrical to each other and whose oblique sides 14a, 15a are in contact with each other. It is composed of fifteen. Therefore, the vertical angle of each of the connecting half tank portions 14 and 15 is (α / 2).

Further, the connecting half tank portion 14,
Among the 15, the stern side edge wall surface 14b corresponding to the bottom of the connecting half tank portion 14 near the center is made to coincide with the edge wall surface 11a of the central tank portion 11, and the connecting half tank portion 15 near the port side Edge wall surface 1 on the stern side corresponding to the bottom part
5b is shaped to match the edge wall surface 12a of the port side tank portion 12.

Therefore, as shown in FIG. 1, the tank 1
The plan view shape is a shape in which three trapezoids are combined so that their hypotenuses are in contact with each other, that is, a fan shape. Although the stern side edge of the tank 1 is bent, this bent portion can be treated with a double-structured horizontal bulkhead arranged inside the hull, so NO.1
It does not affect the layout and shape of the tanks after the tank, that is, the No. 2 tank.

As described above, the tank 1 is divided into three, the left and right port side tank portions 12 are opened outward at a predetermined angle (α) with respect to the central tank portion 11, and the opened gap Connection tank portion 13 arranged in the part,
Since two right-angled triangles symmetrical to each other, that is, having the same apex angle, are combined at their hypotenuses, as shown in FIG. 11 and the corrugates 2 of the membrane material 3 forming the port side tank portion 12 intersect with each other at the same interval (pitch) on the hypotenuse, and the intervals between the corrugates 2 on both sides can also be the same, so that the upper and lower wall surfaces and both side wall surfaces Membrane material 3 on the edge wall surface of
The corrugated gates 2A in the ship width direction (horizontal direction) can have the same mounting interval. Further, as shown in part A of FIG. 2, the corrugate 2B in the bow-stern direction (longitudinal direction) can be connected to a predetermined lateral corrugate 2A. That is, the continuity of the corrugations 2 can be easily maintained in the entire tank, and the corrugated space can be made the same as in the case of the rectangular tank.

Furthermore, since the interval between the corrugates 2 of the central tank portion 11 on the upper wall surface of the tank 1 can be the same as the conventional one, it is possible to provide a liquid dome, a gas dome or the like similar to the conventional one. By using the tank as described above, it is possible to make the corrugated space on both sides of the connecting part at the connecting part of the tank, that is, at the bent part to the bow side in the same plane, and also at the crossing angle between the wall surfaces. Is, for example, 13
Since it can be maintained at 5 degrees or 90 degrees as it is, it becomes possible to use the heat insulating panel that can be used in the conventional rectangular tank as it is, and therefore, the LNG tank can be used for the hull without increasing the cost. Since the shape can be adapted to the bow shape, the dead space of the hull can be effectively used.

[0017]

As described above, according to the structure of the present invention, the conventional rectangular tank is divided into three, and the left and right port side tank portions are opened outward at a predetermined angle with respect to the central tank portion. At the same time, the connection tank portion arranged in this open gap is formed by combining two right-angled triangles that are symmetrical to each other, that is, have the same apex angles. In the hypotenuse, which is the location, the corrugates of the membrane material that make up the central tank part and the port side tank, respectively, intersect at the same interval in the hypotenuse, and the corrugation intervals on both sides can also be the same, and the connections are up and down. Since it is carried out on the wall surface, the angle of intersection between the wall surfaces can be made to be exactly the same as the conventional one. Therefore, the heat insulating panel that can be used in the conventional rectangular tank is installed. It becomes possible to use remain,
Therefore, the LNG tank can be shaped to match the bow shape of the hull without increasing the cost, so that the loading efficiency of the hull can be improved.

[Brief description of drawings]

FIG. 1 is a diagram showing an external configuration of a tank according to an embodiment of the present invention.

FIG. 2 is a plan view showing an arrangement state of corrugates of a tank in the same embodiment.

FIG. 3 is a diagram showing an external configuration of a tank in a conventional example.

FIG. 4 is a plan view of relevant parts showing a state where a tank is mounted on a hull in a conventional example.

FIG. 5 is a plan view showing a modified example of a conventional tank mounted on a hull.

FIG. 6 is a front view of a tank in the modified example.

[Explanation of symbols]

 1 Tank 1a Edge part 2 Corrugated 3 Membrane material 11 Central tank part 12 Port side tank part 13 Connection tank part 14,15 Connection half tank part 14a, 15a Oblique side part

Claims (1)

[Claims] 1. A tank which is mounted on a hull and which is composed of a membrane material in which corrugates are arranged longitudinally and laterally at predetermined intervals, the tank having a rectangular shape in plan view is divided into three in the width direction, and On either side of the front and rear ends of the tank, the left and right port side tanks are opened outward at a specified angle with respect to the central tank, and the gap between the central tank and each port side tank is set. The connecting tank portion is arranged in a portion, and each connecting tank portion is composed of two right-half triangular connecting half tank portions which are symmetrical to each other and whose hypotenuse portions are in contact with each other. A tank for transport vessels.