ES344319A1 - Construction of ships' hulls - Google Patents

Abstract

A method of constructing a ship's hull includes the steps of launching two prefabricated portions H1, H2, Fig. 3, of the hull and effecting permanent connection thereof to each other by, e.g., welding, while they are afloat and temporarily held together by, e.g., external connecting-means (not shown) or bolting internal ribs R1, R2 in one portion to corresponding ribs in the other portion, external connecting- operations on the plates below the waterline L being performed within a caisson 10 that is temporarily placed adjacent said portions in the region of the joint therebetween. The portion H1 may be constructed so that it initially includes the adjacent end section of the portion H2, which section is delimitated by a plane C, this section being severed by, e.g., flame cutting, from the portion H1 before this portion is launched, whereafter the remainder of the portion H2 is constructed such that it is incorporated with said section. This procedure ensures that a satisfactory joint is obtained when the two portions are united in the manner aforesaid. The ribs R1, R2 in said section and the corresponding ones in the portion H1 may be either rendered integral with each other and severed by flame cutting before this portion is launched or provisionally attached to each other by bolts E, Fig. 4, engaging with flanges F on the ribs, which are spaced apart by a packing strip D to provide compensation for loss of material when the plates are cut during severance of the end section, the packing strip being omitted when the two portions are united. Alternatively, the ribs R1, R2 are rendered such that a gap exists between the plates on the adjacent ends of the two portions of the hull when they are brought together, this gap being subsequently bridged by lodging additional plates between said ends and attaching these plates by welding. The hull may comprise more than two prefabricated portions and the method may be employed in effecting enlargement of a hull by insertion of at least one prefabricated portion between the existing portions of the hull. The caisson 10 has the configuration of an open channel and is furnished with upwardlyextending sections at its ends, flanged plates A being provisionally fixed to the sides of each portion of the hull to facilitate sealing of the lateral edges of said sections. Sealing strips 22 are lodged in the edges of the caisson and buoyancy chambers (see Division E1) are formed in the caisson so that it can be conveniently manoeuvred and held against the portions of the hull while water in a working space or gallery 14 is discharged.