OFFSHORE OIL ENGINEERING CO.,LTD Engineering Company
渤海某区块油田开发项目拟采用一种新型的稠油热采模式，即建造一可移动注热平台，通过栈桥与热采平台连接，交替为多个的热采平台提供合格的蒸汽。热采平台平台受风、浪、流等因素的影响会产生相对运动，使生根在栈桥上的蒸汽管线发生拉伸、压缩或扭曲。因此与常规的蒸汽管线或栈桥管线设计相比，移动注热平台的栈桥蒸汽管线设计难点为：高温高压蒸汽不能采用软管连接，只能采用硬管连接；平台运动引起的栈桥位移产生的位移应力及大位移引起的支架脱空导致持续应力超标的问题；注热启停温度变化、波浪随机运动造成的位移变化使管线产生交变应力，逐步积累使管道发生疲劳破坏。结合ASME B31.3和DNV规范，基于CAESAR II 应力分析软件对蒸汽管线进行详细的静态分析及疲劳分析，解决了上述难点，论证了可移动注热平台通过栈桥为热采平台输送蒸汽的可行性。
A new heavy oil thermal recovery mode is proposed for an oilfield development project in Bohai Sea, to build a moveabel steam injection platform, which is connected with thermal recovery platform through bridge, and alternately provide qualified steam for multiple thermal recovery platforms. The steam piping will be stretched, compressed, or twisted duo to relative movement of platforms caused by wind, wave, current and other factors.Therefore, compared with the conventional design of steam pipeline or bridge pipeline, the design difficulties of bridge steam pipeline of moveable steam injection platform are: high temperature and high pressure steam can not be connected by flexible hose, but only by steel pipe; Large bridge displacement will cause large diplacement stress and large sustained stress; Alternating stress, which is prodcued by temeratrue change and displacment change duo to wave random wave movement, gradually accumulates, resulting esulting in fatigue failure of the pipeline. Combined with ASME B31 3 and DNV specifications, and based on CAESAR II stress analysis software, detailed static analysis and fatigue analysis of steam pipeline are carried out. The above difficulties are solved, and the feasibility of transporting steam for thermal recovery platform through movable platform and bridged is demonstrated.