Super e-column on semi-submersible vessel

Abstract

This disclosed embodiments of this invention relate to a semi-submersible vessel. The semi-submersible vessel includes a deck, at least four columns supporting the deck, a first pontoon, a second pontoon, a first brace and a second brace. Each column comprises an outer skin, an inner skin, and a number of reinforcing plates spaced apart from each other and connecting the inner skin to the outer skin, forming a double skin arrangement. The first pontoon is connectable to a first pair of columns and the second pontoon is connectable to a second pair of columns. The first brace is connectable to the first of each of the two pairs of columns and the second brace connects the second of each of the two pairs of columns.

1 . A semi-submersible vessel comprising:
 a deck   a first, second, third and fourth column supporting the deck, each of the columns comprises an outer skin, an inner skin, and a plurality of reinforcing plates connecting the inner skin to the outer skin;   a first and a second pontoon, wherein the first pontoon is connectable to the first and second columns and the second pontoon is connectable to the third and fourth columns;   a first brace connecting the first and third columns; and   a second brace connecting the second and fourth columns, and wherein each of the columns further comprises a block structure at a bottom of a lower part of the column, the block structure having an indent at a top surface for supporting respective first and second braces.   
     
     
         2 . The semi-submersible vessel according to  claim 1  wherein a perimeter of the outer skin at an upper part of the column is larger than a perimeter of the outer skin at a lower part of the column. 
     
     
         3 . The semi-submersible vessel according to  claim 2  wherein the perimeter of the outer skin at the lower part of the column conforms to a super ellipse function with the following expressions, 
       
         
           
             
               x 
               = 
               
                 a 
                  
                 
                     
                 
                  
                 
                   cos 
                   
                     2 
                     r 
                   
                 
                  
                 t 
               
             
           
         
         
           
             
               y 
               = 
               
                 b 
                  
                 
                     
                 
                  
                 
                   sin 
                   
                     2 
                     r 
                   
                 
                  
                 t 
               
             
           
         
         where a is not equal to b and r is equal to 4. 
       
     
     
         4 . The semi-submersible vessel according to  claim 1  wherein a perimeter of the inner skin is the same throughout an upper part and a lower part of the column. 
     
     
         5 . The semi-submersible vessel according to  claim 4  wherein the perimeter of the inner skin is octagonal in shape. 
     
     
         6 . (canceled) 
     
     
         7 . The semi-submersible vessel according to  claim 1  wherein the indent conforms to the surface of the first and second braces. 
     
     
         8 . The semi-submersible vessel according to  claim 1  wherein the plurality of reinforcing plates are evenly spaced apart from each other.