| 摘要 |
According to the present invention, an apparatus for forming large corrugation of a membrane sheet for a liquefied natural gas storage tank comprises: a punch holder having a front stripper, an upper mold, and a rear stripper, and which operates up and down; a front lower mold located on a lower part of the front stripper and having a forward curved part; a rear lower mold located on a lower part of the rear stripper and having a backward curved part; a front supporting stand formed by being extended toward the front of the front lower mold, and having a first cylinder installed on an upper part; and a rear supporting stand formed by being extended toward the back of the rear lower mold, and having a first supporting pin installed on an upper part. The cylinder and the supporting pin are moved up and down. A supporting plate of the cylinder is located in a lower part than the height of a basic material steel plate located on an upper part of the front lower mold and the rear lower mold when the punch holder, the front lower mold, and the rear lower mold are operated. |
