The Structure Design Of The T-type Dual Derrick 7^th Generation Ultra Deep Water Semi-submersible Drilling Platform

In recent years,with the rapid economic development,China has become the world's crude oil imports superpower.At the same time,with the depletion of onshore oil and gas resources,the development of marine oil and gas resources,especially deep-sea oil and gas resources,will be an important growth point for China's future oil and gas resources,and an important way to ensure the country's energy supply and sustainable economic development.As a deep-sea oil and gas development equipment that has emerged in recent years,the double derrick has become one of the key core indicators of the seventh-generation drilling platform because it can significantly improve drilling efficiency and reduce the overall operating cost of the platform.Based on the engineering practice of Yantai CIMC Raffles Offshore Co.,Ltd.and the requirements of the seventh generation drilling ship operation,this paper proposes a T-type double derrick design concept,and aims at the efficiency of single and double derrick,the overall layout of T-type double derrick,T-type double Research on derrick structure design and structural strength analysis.The main work of this paper is as follows:By comparing the drilling times of the same water depth or the same well depth of the single and double derrick platforms,the drilling time difference is used to compare the drilling efficiency of the single and double rigs,and the high efficiency and time advantage of the double rigs in the drilling operation are obtained.According to the drilling performance requirements of the seventh generation drilling rig,the overall layout analysis of the derrick installation equipment for the T-type double derrick scheme is analyzed and the layout scheme is given.At the same time,according to the drilling rig layout and drilling performance requirements,the derrick equipment layout research on the T-type double derrick is carried out.The overall equipment layout of the T-type double derrick is given.According to the T-type double derrick structure type and equipment layout scheme,the force situation under different working conditions of the derrick is calculated,and the load combination mode is obtained.The SACS software was used to test the overall utilization rate of the derrick structure.Based on this,Abaqus software was used to analyze the static structure of the derrick structure.The analysis results show that the T-type double derrick meets the strength requirements under static analysis conditions,and the T-type double derrick The structure design is reasonable.And get the most dangerous position of the derrick,the most dangerous position appears at the upper cross section of the derrick and the bottom joint.The modal analysis model of T-type double derrick is established.The first 20 modes of T-type double derrick are analyzed and calculated,and the modal natural frequency of the first 20 orders is obtained.This result can be used to guide the selection of subsequent derrick moving equipment.