The invention discloses a retrofit technology for
cutting and lengthening ships via a dry-type trolley method. The technology is carried out by prefabricating newly-added sections by sectioning, arranging docking blocks, drawing lines on a ship body, strengthening the structure of the ship body, and
cutting by sectioning. The technology comprises the following main steps of: controlling the docking precision of the ship; paving a combined-type rail, connecting and putting a combined trolley; precisely
lying the ship on a
keel block after the ship docks; arranging a thrust device; adding supports at the front end of a bow section and the rear end of a
stern section of the ship; displacing the bow section; assembling the newly-added sections and folding the newly-added sections with the
stern section; and precisely aligning, locating and folding the bow section with the newly-added sections. The technology is suitable for
cutting and lengthening ships in any mold lines and tonnages and has the advantages of rapid folding speed, high firmness safety, simple and reliable
process operation, short retrofit period and low cost. The folding and locating precisions are high, so that the precise displacement and aligned location of the bow section are effectively guaranteed and the folding precision reaches the level of a newly-constructed ship. On the other hand, the technology is less affected by the change of exterior environment factors such as weather, which is beneficial to the control of the docking period in enterprises.