TLP Conductor Installation Design And Wellhead Stability Analysis

Tension Leg Platform,TLP,is an important kind of platforms in deepwater production of oil & gas.TLP conductor serves as the holding structure for BOP.Unlike the conductor of deepwater exploratory wel,TLP conductor has the characteristics of pile groups,long working period and complex environmental loading.A Block project team in South China Sea decided to use TLP for developing.To ensure the safety and efficiency,researches on the TLP conductor installation design and welhead stability analysis would be necessary and significant.Researches on TLP were focused on platform design and stability,and were insufficient in theory and experiment for TLP well interference,conductor bearing capacity and wellhead stability analysis in long working period.Based on literature review on overseas TLP,the study optimized jetting as the method to run TLP conductor by analyzing targeted area's seabed soil characteristics,subsea welhead spacing,operation time and expenses.Combining research techniques of theoretical analysis,numerical modeling and field experiment,the study carried out researches on affected seabed soil range during running conductors,TLP conductor installation parameters and welhead stability analysis in multi engineering conditions.The research findings achieved includes elastic and plastic zone's stress and displaceme nt calculation model,TLP conductor bearing capacity calculation model and conductor bearing capacity reduction coefficient function relationship.Research results were applied in South China Sea A block.The designed running depth was 70 m and the safe waiting time was 2.5 h.The finite element analysis indicated that TLP conductor would meet the requirments except in a thousand year frequency operation environment and 2% wellhead deviation condition.