油气集输管道穿越处套管端封堵方案探讨

道路穿越中常通过钢制套管保证埋地管道安全。套管管端封堵为规范强制要求。高温、高压集输管道形变趋势大,可能影响套管端密封性,应对现有封堵方式进行深入探讨。根据相关规范要求,结合管道轴向应力理论,解释了埋地管道活动规律,推导并验证了套管封堵端的受力计算公式,分析了常用封堵方案(刚性封堵和柔性封堵)用于集输管道系统的可靠性,提出了套管端封堵的完善建议。结果表明,推导的封堵端受力计算方法与软件模拟结果接近;集输管道所需约束力通常较大,刚性封堵无法提供足够锚固力,主管道的应变将破坏其稳定性;柔性封堵能够提供满足管道活动的位移裕量,可作为集输管道穿越中首选套管端封堵方案。本文的研究成果为套管封堵的安全设计提供了参考与借鉴。

Discussion on the Extreme Pressure of LPG Transportation Pipeline

Presently, the production and usage of Liquefied Petroleum Gas (LPG) are growing, and the LPG transportation technology develops greatly. The safety of pipeline system is closely related to the system pressure. There are some special points for extreme pressure in LPG pipeline system comparing with the common crude oil pipeline or product oil pipeline, because of the LPG physical properties. In this paper, taking the extreme pressure in LPG pipeline as a research object, the origin of impact of pressure on LPG pipeline was discussed based on the steel pipeline strength theory, the safety and reliability of LPG pipeline were analyzed under the extreme operation condition of common liquid pipeline. The extreme influence of LPG thermal expansion on pipeline was deeply studied and confirmed, according to the special working condition in LPG pipeline. The results show that that the extreme system pressure of LPG pipeline under pigging and re-start condition is almost same to that under normal operation condition, and the extreme pressure increases under water hammer condition, and then, the system pressure rises greatly when pipeline shutdown and warming up. The study result can provide reference for relative scholars and engineers.