Strength Analysis Of Derrick Onoffshore Drilling Platform

Derrick of offshore drilling platform is currently the field where our domestic major offshore equipment supplier is just stepping into. Derrick is the structural basis of the whole drilling package, which serves to hoist items and mount other lifting equipment to play the role of drilling operations. For the offshore drilling platform derrick, domestic research information is very scarce, so the stress characteristic of such a derrick structure is almost unknown. It is difficult to fully grasp its structural characteristics, identify potential hazardous areas. Derrick makes these difficult to guarantee the safety, but also hindered the design and development of China’s offshore equipment.In this thesis, the structural strength of offshore drilling derrick platform is investigated, this study provides relevant technical and reference materials for the design of our own offshore drilling platform derrick, contribute to the development of China’s offshore equipment. The research results can be applied to the structure analysis of variety types of derricks.In this thesis, the basic structure strength analysis method is firstly determined, followed by the analysis procedure, analysis contents and strength criteria. Secondly, applied loads are determined such as wind load, hook load, torque, unit motion acceleration etc., followed by the modeling of derrick and some critical analysis skill in FEM analysis. At the last FEM analysis is carried out and the stress level and distribution is studied. The main outcome of this thesis is listed as below:(1) Lower part of the supporting legs have high stress level, it should be reinforced if the operation capacity need to be upgraded.(2) The maximum UC of water table is 0.91, the design of the I-beam is just economic and reasonable for a hook load of 1000 t.(3) Summarized the key party of joint calculation as well as the calculation procedure.