Advances in technology of deepwater drilling riser and wellhead

Key words:  deepwater  drilling riser  wellhead  pre-drilling design and operation  integrity  safety  risk

Abstract:

Drilling riser and wellhead system is an important and vulnerable component of the whole deepwater drilling system. Appropriate design and utilization of drilling riser and wellhead system are important for the success and safety of deepwater drilling and completion. Therefore, the research on deepwater drilling riser and wellhead system in the South China Sea was done early. Mechanical analysis model of deepwater drilling riser and wellhead system was built and the riser and wellhead system pre-drilling design and operation technique were developed. The analysis methods for wave induced fatigue, vortex induced fatigue, wear and riser connector integrity of riser and wellhead system were developed. Furthermore, the integrity management strategy for deepwater drilling riser and wellhead system was improved. The risk assessment frameworks for key equipments and operations of deepwater drilling riser were developed and the security measures for riser system under typhoon environment were studied. On the basis of these results, deepwater drilling riser operation management software (DDROM) was developed. The deepwater drilling riser and wellhead system pre-drilling design and operation assessment for 6wells in the South China Sea were carried out. The research results have been put into application in deepwater drilling operation in the South China Sea and good application result was achieved. The research developments of deepwater drilling riser and wellhead system are reviewed and the future research directions are also recommended.