页岩气压裂高压管汇失效风险分析及防控措施

Failure Risk Analysis and Prevention Measures of High-pressure Tube in Shale Gas Fracturing Construction

针对大排量、高压力页岩气压裂施工作业中存在的高压管汇失效风险,分析了某公司近年来的高压管汇失效事故事件,识别出了常见的失效形式及部位,构建了基于计算流体力学的固液两相流射流模型,模拟计算了失效的破坏力和伤害范围。研究结果表明:刺漏是高压管汇最常见失效形式,弯头、三通等应力集中区是刺漏失效的高危部位;100 MPa工况时刺漏影响范围可达100 m,离刺漏点1 m处,流体流速为260 m/s,打击压力达3.5 GPa,远超防护钢板抗剪切强度。根据风险分析及事故模拟结果,从本质安全、工艺改进、管理、信息化提升4个维度提出了防控措施,为页岩气压裂施工作业安全防控措施的制定提供了参考。

Aiming at the failure risk of high-pressure manifold in large displacement and high-pressure shale gas fracturing construction,the failure accidents of high-pressure manifold in a company during the past years were analyzed,and the common failure forms and areas were identified.A solid-liquid two-phase jet model based on computational fluid dynamics was constructed to calculate failure force and damage range.The results showed that the piercing was the most common failure mode of high-pressure manifold,and the stress concentration areas such as elbow and tee were the high-risk parts of the piercing failure.Under the 100 MPa condition,the influence range of piercing leakage could reach 100 m,1 m away from the piercing point,the fluid flow rate was 260 m/s,and the impact pressure was 3.5 GPa,which was far beyond the shear strength of protective steel plate.According to the results of risk analysis and accident simulation,prevention and control measures were put forward from four dimensions of intrinsic safety,process improvement,management and information promotion,which provided a reference for the formulation of safety prevention and control measures for shale gas fracturing construction.