Anchor structure and LNG storage tank including the same
The present invention relates to an anchor structure able to actively cope with hull deformation, and to a liquid natural gas storage tank and a production method for a liquid natural gas storage tank comprising the anchor structure. According to one embodiment of the present invention, an anchor structure is provided wherein an anchor structure, for linking a sealing wall and an inner wall of a liquid natural gas storage tank, comprises: an anchor member adapted such that a joining part, which is joined to the sealing wall, can slide horizontally; and a thermally insulating material formed around the anchor member.
1. An anchor structure for connecting a sealing wall to an inner wall of an LNG storage tank, comprising:
an anchor member having a joint joined to the sealing wall and horizontally slidable; and
an insulator formed around the anchor member,
wherein the sealing wall comprises a primary sealing wall directly contacting liquefied natural gas (LNG) and a secondary sealing wall disposed under the primary sealing wall, the primary sealing wall and the secondary sealing wall being joined to the joint of the anchor member,
wherein the joint comprises a first joint joined to the secondary sealing wall and a second joint joined to the primary sealing wall.
2. The anchor structure according to claim 1 , wherein a support board is interposed between the primary sealing wall and the secondary sealing wall to maintain a constant distance therebetween.
3. The anchor structure according to claim 1 , wherein the anchor member comprises an anchor support rod passing through the anchor structure and an anchor support plate perpendicularly connected to the anchor support rod and placed on the insulator.
4. The anchor structure according to claim 3 , wherein the first joint comprises a first cap portion joined to the secondary sealing wall and a first flange radially extending from a lower end of the first cap portion, and the first flange adjoins the anchor support plate without being secured to the anchor support plate.
5. The anchor structure according to claim 4 , wherein the anchor member further comprises an anchor support cap composed of a second cap portion and a second flange radially extending from a lower end of the second cap portion, the second flange covers the first flange, and an edge of the second flange is secured to the anchor support plate by welding.
6. The anchor structure according to claim 1 , wherein the anchor member comprises an anchor support rod passing through the anchor structure,
wherein the anchor structure further comprises an anchor support bolt cap disposed under the insulator, and
wherein the anchor support rod can pass through the anchor support bolt cap.
7. The anchor structure according to claim 6 , wherein the anchor support rod has a threaded groove formed at a lower end thereof such that the lower end of the anchor support rod having passed through the anchor support bolt cap is coupled to an anchor member securing nut.
8. The anchor structure according to claim 6 ,
wherein the insulator has a first through-hole through which the anchor support rod can pass,
wherein the anchor support bolt cap composes of a cap portion having a second through-hole through which the anchor support rod can pass and a flange radially extending from a lower end of the cap portion,
wherein the anchor support rod has a threaded groove formed at a lower end thereof such that the lower end of the anchor support rod having passed through the first through-hole and the second through-hole is coupled to an anchor member securing nut to be secured to the anchor support bolt cap, and
wherein the anchor support rod is movable up and down.
9. The anchor structure according to claim 8 , further comprising:
a first anchor lower plate attached to a lower end of the insulator; and
a second anchor lower plate disposed under the first anchor lower plate,
wherein the anchor support bolt cap is inserted between the first anchor lower plate and the second anchor lower plate.
10. The anchor structure according to claim 9 , wherein the first anchor lower plate has a third through-hole through which the anchor support rod can pass, and the second anchor lower plate has a fourth through-hole through which the anchor support rod can pass, the third through hole being sized to allow the anchor support rod and the first anchor lower plate to be spaced apart from one another, and the fourth through hole being sized to allow the anchor support rod and the second anchor lower plate to be spaced apart from one another.
11. The anchor structure according to claim 1 , further comprising:
a first anchor lower plate attached to a lower end of the insulator;
a second anchor lower plate disposed under the first anchor lower plate; and
a reinforcing plate interposed between the first anchor lower plate and the second anchor lower plate.
12. An LNG storage tank comprising the anchor structure according to claim 1 , comprising:
a heat insulating wall disposed on an inner wall of the storage tank to form a heat insulating layer;
a sealing wall disposed on a surface of the heat insulating wall to seal the LNG storage tank in a liquid-tight manner; and
the anchor structure connecting the sealing wall to the inner wall of the storage tank,
wherein the anchor structure comprises an anchor member having a joint joined to the sealing wall and horizontally slidable.
13. A ship comprising the LNG storage tank according to claim 12 .