剪切闸板防喷器剪切性能评价

Shear Performance Evaluation of Shear Ram Blow-out Preventer

剪切闸板防喷器是井控设备的重要组成部分之一,其作用是在钻井过程中遇到突发情况时及时剪断钻杆并密封井口,其剪切性能直接关系到钻井作业的安全。以某新型上直下V结构的剪切闸板防喷器为研究对象,通过显示动力学模块对剪切闸板剪切钻杆的过程进行数值仿真模拟,分析研究闸板的剪切性能。并用该剪切闸板分别剪切5 in和5.5 in两种不同规格的S135钻杆,以研究其对不同规格钻杆的适应性,分析经验公式计算值和仿真值存在差异的原因,也探讨了在有井压,有悬重情况下剪切力的变化规律。结果表明:该新型剪切闸板能够顺利剪断5 in和5.5 in两种不同规格的S135钻杆,具有较好的适应性。并且经验公式相对保守,可采用适当系数进行修正。同时在有井压的情况下,剪切力随着井压增大而增大,当井压过大时,建议增加增压缸;在有悬重时,剪切力随悬重的增加逐渐下降,钻杆越长越利于剪切。该研究可以为剪切闸板防喷器的设计和使用提供技术指导。

Shear ram blow-out preventer is one of the important parts of well control equipment.Its function is to cut off the drill pipe and seal the wellhead in case of emergency in drilling process.Its shear performance is directly related to the safety of drilling operation.A new type of up-straight down-V-structure shear ram blow-out preventer was taken as the research object.The numerical simulation of the process of shearing drill pipe with the shear ram was carried out through the display dynamics module to analyze the shear performance of the ram.The shear ram was used to shear S135 drill pipes of 5 in and 5.5 in respectively In order to study the adaptability of S135 drill pipe with different specifications,the reasons for the difference between the calculated values of empirical formula and the simulated values were analyzed.The variation rule of shear force under the condition of well pressure and suspension weight was also discussed.The results show these follows.The new shear gate can cut the S135 drill pipe with different specifications of 5 in and 5.5 in smoothly,and has good adaptability.The empirical formula is relatively conservative and can be modified by appropriate coefficients.At the same time,in the case of well pressure,the shear force increases with the increase of well pressure.When the well pressure is too high,it is suggested to increase the pressure booster cylinder.When there is hanging weight,the shear force decreases gradually with the increase of hanging weight,and the longer the drill pipe is,the more conducive to shearing.The research can provide technical guidance for the design and application of the shear ram blow-out preventer.