Patent ID: 8327783

Claim:
A moonpool formed in a drillship, comprising: a first space formed by being penetrated from a bottom surface through an upper deck of the drillship so as to carry out a drilling operation; and a second space formed on a side of the first space in a lengthwise direction of the drillship, a bottom of the second space being open toward a lower side of the drillship, wherein a transverse section of the first space and the second space respectively has the shape of a quadrangle that is extended in a lengthwise direction of the drillship, wherein an opening opened toward a lower side of the first space maintains a constant transverse width and then becomes narrower in a stern-side direction of the drillship, wherein a baseplate that is placed on a same plane as a bottom surface of the drillship is installed on both corners of an end of the opening opened toward the lower side of the first space, the both corner of the end located in a stern-side direction of the drillship, the baseplate having the shape of a triangle.