深水钻井装置浅水区动力定位方式风险研究

当今世界上先进的深水钻完井装置具有锚泊及动力定位2种方式作业能力,业内推荐做法为水深小于1 500 m都可以使用锚泊方式定位,对于动力定位方式在浅水区的适应性和风险则缺少分析。通过对动力定位方式的原理及其漂移限制进行论述,包括了浅水定位的理论限制以及规避风险的措施,提出如何设定观察圈范围及浅水作业使用动力定位方式时应考虑因素、作业风险及应对措施,除了环境及深水钻井装置应急解脱时间影响因素外,还将考虑隔水管系统极限、水下井口和结构套管强度、通讯系统、定位传感器系统等影响因素,应对措施包括井口设备选择、隔水管系统分析、人员交流培训和使用者和承包商协议等,对浅水区使用定位方式作业有一定的指导意义。

Study on dynamic positioning risks of deepwater drilling device in shallow water area

The world’s advanced deepwater drilling and completion devices are divided into mooring and dynamic positioning. The industry recommended practice is mooring locating for water depth less than 1 500 m, while the adaptability and risk of dynamic positioning in shallow waters are little studied. This paper describes the principle and drift limitations of dynamic positioning, including the theoretical limitations and the measures to avoid risks. It also suggests on how to set the observation scope and proposes the factors, operational risks and countermeasures to be considered in using dynamic positioning for operations in shallow waters. In addition to the environmental factors and those that affect the emergence release time of deepwater drilling device, the extreme limits of riser system, strength of subsea well head and structural casing, communication system, and positioning sensor system also need to be considered. The countermeasures include well head device selection, riser system analysis, staff communication and training, user and contractor agreement, etc. The research results can provide some guidance on the use of locating method in shallow waters.