Welding Deformation Analysis And Study Of Precision Control During Ship Repair And Conversion

In the context of shipping market continuing receding,plenty of shipping company and offshore company chose the cheap and old vessel to repair and conversion to keep low expending.Nowadays,on the market there are several kinds of ship conversion: single shell tanker to double shell tanker,single shell tanker to VLOC,tanker to FSO/FPSO/FDPSO,special vessel conversion and so on.But in general,anyhow,ship is made up of a lot of steel plate welded.From parts fit up to block assembly even to block erected on slipway,welding is wildly used during every procedure of ship construction.As the repair and conversion developing and shipping market downturn,shipyards that used to pursuing project speed and ignoring production precision,already can not match the nowadays’ market.How to cost decreasing and benefit increasing already become the mainstream among the main shipyards all over the world.At present,fix,fire up,measuring and all the methods of preventing weld deformation already account for 20%-30% period of offshore project conversion and repair,if we can learn from some successful example and experience,summarize several typical kinds of way to prevent and control weld deformation,it will largely increase labor productivity and decrease repair(conversion)period.The article main idea and method is summarizing the typical case of welding deformation occurred during ship damage repair,hatch cover plate and other thin plate weld,tanker converted to FPSO,typical tank internal structure renew,study the reason of weld deformation,instruct how to prevent-control-promote-avoid deformation from technical and productive aspects,forming a set of theories to solve the relevant problem on site,and develop useful,portable fixture which can control weld deformation effectively,so that reach the goal of saving material and manpower.