自升式钻井平台安全作业载荷动态效应的准静态分析

Quasi-static analysis of the dynamic effect of a jack-up rig's work load during safe drilling operation

国内外都在加速对海洋油气资源的开发利用,而恶劣的环境则是影响近海自升式平台作业安全的主要因素之一,国外近年来有20多条平台因飓风(台风)沉没或严重受损;国内目前对自升式平台在极限环境条件下的安全性研究较少,在作业中采取了比较保守的策略,加之向海外市场扩张,使我国有限的钻井平台资源供需矛盾日渐凸显。为此,通过运用动态效应的准静态分析法,对钻井平台承受的风、波、流等环境载荷、惯性力和自身载荷等参数进行了计算,同时对其桩腿、升降/锁紧系统、船体等主要结构和预压载性能、桩靴承载性能、抗倾覆性能、最大弹性变形量等主要参数进行了校核,并以现今主流的JU2000E船型自升式钻井平台为例,进行了相关的环境参数的校核演算。该项技术已在中国沿海及海外自升式钻井平台作业市场进行了100余次应用检验。结果表明,准静态分析法的分析过程简捷,评估的准确性高,平台作业的安全性取得了满意效果。

Severe sea environment is a major disadvantage affecting the safety of jack-up rig operation in offshore drilling. In recent years, more than 20 rigs sank or were severely damaged due to hurricanes （typhoons） in foreign countries. Since few researches have been conducted in China on the jack-up rig safety under extreme environmental conditions, domestic operation adopts relatively conservative practices. With limited rig resources at home, the imbalance continuously grows between the supply and demand. In view of this, a quasi-static analysis of dynamic effect was conducted through calculating parameters born by the jack-up rig including inertia force, self-load, and such environmental loads as wind, wave and current. In addition, other main structures and parameters were calibrated, including legs, lifting/locking systems and hulls, as well as pre loading performance, spudcan loading capacity, overturning resistance, and maximum elastic deformation. Moreover, JU2000E jack-up rig, the current mainstream rig, was taken as an example for calibrating and calculating relevant environmental parameters. This technology has been tested in over 100 applications in the jack up rig operation market in the coastal area at home and abroad. According to the results, the quasi-static analysis is simple in process and accurate in evaluation, and the rig operation safety is improved with a satisfactory effect. Therefore, this technology can benefit and promote the rig operation safety and acceleration of developing and utilizing suhsea oil and gas resources.