Research On The Lifting And Mounting Technology Of Superstructure

Superstructure lifting is a comprehensive technology involves many aspects whichassociate and work closely together with each other. Considering various aspects, a study ofsuperstructure mechanical problems and a systematical design of lifting technology are veryimportant to ensure the safety of lifting process.Taking every aspect which affects superstructure lifting technology into consideration,an advisable set of lifting scheme is addressed. With the help of FE software ABAQUS,contact strength and ultimate strength of lifting lug used for superstructure lifting is carriedout by which safety margin of lifting lug is obtained. MSC FE software is used to evaluatesuperstructure strength during the whole lifting process and reliability of currently adoptedsafety factor is confirmed. According to the different characteristics of superstructure andtaking the design of lifting scheme of105000DWT oil tanker as an example, design andimplementation of lifting scheme is elaborated, which provides a certain reference andguidance for the design of lifting scheme for other superstructures. The main conclusionsare as follows:(1) Radius of shackle structure which matches the lug structure in this paper is95%ofthe lug radius.(2) Based on the contact strength results of different lugs, three methods are addressedto simplify the contact force, which compared with original contact algorithm, are lesser incomputation time and higher in accuracy, and provide a reference for practice.(3) The ultimate load of lifting lug is4times of its designed load. In real lifting process,using the lug structure under its working load is safe and reliable.(4) Stress and mass ratio of A type lifting lug is the highest under both designed andultimate condition, which indicates a higher availability and a greater bearing capacity.(5) Safety factor is1.1or1.2for superstructure lifting, which has a certain accuracy incondition of a long lifting acceleration time and a small lifting speed, while in the contrarycondition, this safety factor is a little low. If lifting capacity is allowable, using portal jibcrane to lift the superstructure has more security.(6) A complete and detailed design and implementation of superstructure lifting schemeis obtained and combined with a given example, a certain reference and guidance for thedesign of lifting scheme for other superstructures is provided.