JP2013124100A - Independent type tank support structure system of lng ship - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an independent type tank support structure system of an LNG ship capable of preventing deformation by a load caused by weight of LNG, tank dead weight and hull motion in a joining part of an LNG tank and a hull of the LNG ship.SOLUTION: This independent type tank support structure system includes a tube 33 inserted into a space part between the LNG tank 10 and the hull 20 and supporting the LNG tank by equal distribution support force, both compressors 30 inserted inside both bottom parts of the hull and supplying air to the inside of the tube, both pipes 31 connected to both compressors and the tube and making the air flow in the tube, both adjusting valves 32 respectively arranged in optional places of both pipes and adjusting an inflow quantity of the air to the inside of the tube, a pressure gauge 35 for measuring and displaying an excess inflow quantity of the air when the inflow quantity of the air to the inside of the tube exceeds a predetermined value, a sensing part 36 for sensing the excess inflow quantity of the air from the pressure gauge, and a pressure reducing valve 37 for making the excess inflow quantity of the air flow out to the outside of the tube by receiving a signal of the sensing part.

Description

  The present invention relates to a stand-alone tank support structure system for an LNG ship, and more specifically, when a tank storing LNG in a cryogenic state for transporting LNG at sea is installed in the LNG ship, The present invention relates to an independent tank support structure system for an LNG ship for minimizing deformation of the tank and the LNG ship hull due to the weight of the tank and the load caused by the hull motion.

  In general, the independent LNG tank provided in the LNG ship can be roughly classified into a MOSS type LNG tank 100 shown in FIG. 1 and an SPB type LNG tank 200 shown in FIG.

  In order to store the cryogenic LNG, the LNG tank is mainly made of aluminum, and a heat insulating material (insulation) is provided on the outer wall to prevent heat loss.

  The MOSS type LNG tank 100 is provided on the hull 400 of the LNG ship by supporting a skirt 450.

  For this reason, when the tank is filled with LNG, the tank's own weight and the weight of the LNG are all transmitted to the hull 400 via the skirt 450. At this time, the tank equator 300 and the arrangement of the skirt 450 of the hull 400, etc. A large load is locally applied to the structural discontinuity, and the possibility that the structure is damaged is greatly increased.

  In other words, since all the load is transmitted through the skirt 450, the tank equatorial section 300 extends in the height direction due to the load, contracts in the width direction, buckles, and increases in stress. It will be done.

  In addition, in order to withstand an excessive load, not only the skirt 450 but also the hull 400 must be structurally strengthened, and a tank capable of further increasing the LNG load due to the excessive load is manufactured. Difficult to do.

  The above-mentioned problems are observed not only in the MOSS type LNG tank 100 but also in the SPB type LNG tank 200.

  In order to solve the above-described problems, the present invention provides a load caused by the weight of the LNG, the tank's own weight, and the hull movement at the joint portion between the tank storing the LNG and the hull of the LNG ship provided with the tank. An object of the present invention is to provide a stand-alone tank support structure system for an LNG ship that can prevent deformation due to the above.

  Another object of the present invention is to provide an independent tank support structure system for an LNG ship that can safely transport LNG to a destination by preventing deformation of the joint portion between the tank and the hull of the LNG ship. There is a place to do.

  Furthermore, still another object of the present invention is to prevent the deformation of the joint portion between the tank and the hull of the LNG ship, thereby making it possible to manufacture a tank having a larger LNG load than the conventional LNG load. An independent tank support structure system for an LNG ship is provided.

  In order to achieve the above-described objects, the independent tank support structure system for an LNG ship according to the present invention is a system for connecting a MOSS-type and SPB-type LNG tank for loading LNG of an LNG ship and a hull of the LNG ship. In order to prevent deformation, a tube inserted in the space between the LNG tank and the hull and supporting the LNG tank with equally distributed support force, and inserted in both bottoms of the hull respectively into the inside of the tube Both compressors for supplying air, both pipes connected to the compressors and tubes, respectively, for allowing air to flow into the tubes, and the inflow of air to the inside of the tubes respectively provided at arbitrary locations of the pipes Both control valves for adjusting the amount, a pressure gauge for measuring and displaying the excess air inflow when the inflow of air into the tube exceeds a predetermined value, and an empty air from the pressure gauge. A sense unit for sensing the excess inflow, receives a signal of the sense portion and characterized in that it comprises a pressure reducing valve for discharging the excess inflow amount of air to the outside of the tube, the.

  Preferably, the tube is configured such that a double tube composed of an outer tube and an inner tube and a single tube are selected.

  Preferably, when the double tube is used, a joint pipe for joining pipes respectively connected to the two compressors is further provided. In the middle of the joint pipe, two joints are connected by the two compressors. A control valve is further provided to equalize the air pressure in the heavy tube.

  According to the independent tank support structure system for an LNG ship according to the present invention, when a tank storing LNG is installed in the LNG ship, the LNG load and the tank load prevent deformation of the joint portion between the tank and the hull. There is an effect that can be.

  Further, deformation of the joint portion between the tank and the hull is prevented, and LNG can be stably transported to the destination.

  In addition, since the tank is supported with an evenly distributed support force and air is used, the connecting portion between the tank and the hull can be reduced in weight, and the construction cost and material cost can be reduced. It is structurally safe because it does not occur.

  In addition, a LNG tank larger than the conventional LNG tank can be manufactured, and the LNG load can be increased.

It is sectional drawing which shows arrangement | positioning and the tank support structure of the conventional MOSS type | mold LNG tank. It is sectional drawing which shows arrangement | positioning and the tank support structure of the conventional SPB type LNG tank. FIG. 3 is a cross-sectional view showing a MOSS type LNG tank arrangement structure in which the equator portion according to the present invention is extended and the tank capacity is increased by providing a single tube (when LNG is not loaded on the tank). In FIG. 3, it is sectional drawing which shows the state which loaded LNG on the tank. FIG. 3 is a cross-sectional view showing a MOSS type LNG tank arrangement structure according to the present invention with a double tube comprising an outer tube and an inner tube for safety. It is sectional drawing which provides a single tube in the arrangement structure of the SPB type LNG tank concerning the present invention, and shows (when LNG is not loaded in the tank). In FIG. 6, it is sectional drawing which shows the state which loaded LNG on the tank.

  In the case of an LNG (liquefied natural gas) ship, the volume ratio is reduced to 1/600 by lowering the natural gas in the gaseous state to -163 ° C and liquefying, and a large amount of LNG is transported at one time. In order to transport natural gas using LNG, a large-scale low-temperature liquefaction facility is required at the port entrance or gas field, and a ship thermal insulation device is also required to maintain the temperature of the LNG ship's ship at -163 ° C. Moreover, a cooling device is also required to maintain a predetermined temperature.

  When liquefied LNG is loaded on an LNG ship, a tank capable of storing LNG is provided on the hull. At this time, the tank is provided in a state supported by the hull by the support of the skirt. It is done.

  The tank can be roughly classified into a MOSS type tank (see FIG. 1) and an SPB type tank (see FIG. 2).

  Therefore, the independent tank support structure system for an LNG ship according to the present invention is a technique applied when the MOSS tank and the SPB tank are provided in a state supported by the hull.

  Hereinafter, an independent tank support structure system for an LNG ship according to the present invention will be described with reference to the accompanying drawings.

  FIG. 3 shows a state in which LNG is not loaded on the MOSS type LNG tank 10. The present invention employs a structure in which the LNG tank 10 is supported by the hull 20. The LNG tank cover 5 is provided outside the LNG tank 10, and both sides of the LNG tank 10 engage with the skirt 25. The skirt 25 is engaged with the hull 20 and the tube T (in the space between the LNG tank 10 and the hull 20 is supplemented to compensate for the load of the LNG tank 10 being concentrated on the skirt 25. A single tube 33) is provided, and compressors 30 for supplying air to the inside of the tube 33 are inserted one by one inside the bottoms of the hull 20, and the air discharged from both the compressors 30 is supplied. One side part of the pipe 31 which becomes a conveyance path for flowing into the inside of the tube 33 is connected to each compressor 30, and the other side part is connected to the tube 33. 1 is connected to a regulating valve 32 for allowing the air discharged from the compressor 30 to flow into the tube 33 by adjusting it to a predetermined amount, and the amount of air flowing into the tube 33 is predetermined. When the value is exceeded, a pressure gauge 35 is provided so that the numerical value of the excess air amount can be seen at a glance, a sensing unit 36 for sensing the excess air inflow amount from the pressure gauge 35 is provided, and the signal of the sensing unit 36 And a discharge pipe 38 for discharging the excess air amount that flows out through the pressure reduction valve 37 to the outside is provided on each side of the hull 20. It is characterized by being able to.

  For this reason, when LNG is loaded in a liquefied state in the LNG tank 10, as shown in FIG. 4, air flows into the tube 33 between the LNG tank 10 and the hull 20, and the LNG tank 10. The tube 33 supports the lower portion of the LNG tank 10 to reduce the transmission of the load of the LNG tank 10 to the skirt 25, and a compressed air layer is formed in the tube 33 surrounded by the LNG tank 10, the skirt 25, and the hull 20 to form the LNG tank 10. The weight of the LNG tank 10 is flexibly transmitted to the hull 20 by supporting the weight of the LNG tank 10 with an evenly distributed supporting force.

  That is, when the LNG tank 10 is not filled with LNG, the LNG tank 10 is supported only by the skirt 25, and if LNG is loaded on the LNG tank 10, the air generated in the compressor 30 is passed through the pipe 31. It injects into the internal space of the tube 33 between the hull 20 and the LNG tank 10.

  Of course, the space of the tube 33 into which air is injected is a sealed space, and the hull 20 is configured so as to sufficiently withstand the load of the LNG tank 10.

  The adjustment valve 32 that adjusts the amount of compressed air adjusts the amount of air supplied from the compressor 30 to flow into the tube 33, and the pressure gauge 35 has an excess inflow amount of air into the tube 33. If there is, it is displayed numerically so that it can be seen at a glance. When the sensing unit 36 senses the excess inflow of air from the pressure gauge 35, it uses the pressure reducing valve 37 to indicate the excess inflow of air. The pressure reducing valve 37 receives the signal from the sensing unit 36 and discharges the excess air inflow to the outside of the tube 33. At this time, the excess inflow of the discharged air is And flows out through the discharge pipe 38.

  The sensing unit 36 operates and adjusts the pressure reducing valve by sensing a pressure difference of 0.5 bar or more.

  According to the independent tank support structure system for an LNG ship of the present invention having such a configuration, damage that may occur locally in the LNG tank 10 and the hull 20 is prevented, and ultimately a larger capacity is achieved. By providing the LNG tank 10 in the hull 20, it is possible to provide the hull 20 capable of transporting a large amount of natural gas.

  In the independent tank support structure system for an LNG ship according to the present invention, as shown in FIG. 5, a double tube 34 comprising an outer tube 34a and an inner tube 34b is selectively provided between the LNG tank 10 and the hull 20. Provided.

  The double tube 34 may be engaged with the inner tube 34b wrapped around the outer tube 34a, and the outer tube 34a and the inner tube 34b are engaged by a binding means. May be.

  When the double tube 34 is provided, a joint pipe 39 for joining the pipes 31 connected to the compressors 30 is further provided, and a control valve 40 is provided in the middle of the joint pipe 39. Is additionally provided.

  Therefore, the air supplied from one of the compressors 30 flows into the outer tube 34 a along the pipe 31, and the air supplied from the other compressor 30 flows along the pipe 31 to the inner side. At this time, a part of the air supplied from both compressors 30 flows into both pipes 31 and flows into the joint pipes 39 connected to both pipes 31. Further air flow is blocked by a control valve 40 connected in the middle.

  Ultimately, the pressures acting on the outer tube 34a and the inner tube 34b are equal, which means that there is no pressure difference between the outer tube 34a and the inner tube 34b. That is, the pressure is zero.

  For this reason, the operation is interlocked so that the air pressure supplied from both compressors 30 becomes equal, and a control valve is provided. Therefore, if necessary, the control valve is opened and the outer tube 34a and the inner tube 34b By reducing the pressure difference between the two, the air pressure becomes equal.

  In order to support the LNG tank 10, the air pressure required for delivery from the compressor 10 may be 5 to 10 bar at maximum.

  As shown in FIGS. 6 and 7, the LNG carrier independent tank support structure system of the present invention having the above-described configuration is similarly applied to the space between the SPB type LNB tank 10 and the hull 20. Needless to say, it is applicable.

5 LNG tank cover 10 LNG tank 15 Equatorial section 20 Hull 25 Skirt 30 Compressor 31 Pipe 32 Control valve 33 Tube 34 Heavy tube 34a Outer tube 34b Inner tube 35 Pressure gauge 36 Sense section 37 Pressure reducing valve 38 Discharge pipe 39 Joint pipe 40 Control Valve T Tube 100 MOSS type LNG tank 200 SPB type LNG tank 300 Equatorial section 400 Hull 450 Skirt

Claims (3)

In order to prevent deformation of the joint portion between the LNG tank for loading the LNG of the LNG ship (MOSS type and SPB type) and the hull of the LNG ship, it is inserted into the space between the LNG tank and the hull). A tube (T) for supporting the tank with an evenly distributed supporting force;
Both compressors that are respectively inserted in the bottoms of the hull and supply air to the inside of the tube (T);
Both pipes connected to the compressor and the tube (T), respectively, for allowing air to flow into the tube (T);
Both control valves respectively provided at arbitrary locations of the pipes for adjusting the amount of air flowing into the tube (T);
A pressure gauge that measures and displays the excess inflow of air when the inflow of air into the tube (T) exceeds a predetermined value;
A sensing unit that senses an excess inflow of air from the pressure gauge;
A pressure reducing valve that receives the signal of the sense unit and flows out the excess inflow of air to the outside of the tube (T);
An independent tank support structure system for an LNG ship characterized by comprising:   2. The independent tank support structure for an LNG ship according to claim 1, wherein the tube (T) is configured such that a double tube comprising an outer tube and an inner tube and a single tube are selected from the two. system.   When the double tube is used, a joint pipe for connecting pipes respectively connected to the two compressors is further provided, and in the middle of the joint pipe, the air pressure in the double tube is obtained by interlocking the two compressors. The LNG ship independent tank support structure system according to claim 2, wherein a control valve is further provided so as to be equal to each other.