高含硫气田快开盲板密封材料耐硫性能评价与失效分析

Evaluation of Sulfur Resistance and Failure Analysis of Fast-opening Blind Sealing Material of High-sulfur Gasfields

以普光油气田现场所用快开盲板密封橡胶为研究对象,进行了室内模拟H2S/CO2环境的腐蚀实验,分析了其腐蚀前后的外观、力学性能、微观结构及红外光谱的变化,推断了快开盲板橡胶密封材料的腐蚀机理。结果表明,腐蚀后密封橡胶材料的力学性能损失严重,主要是由三种原因造成的,一是加压时溶解在密封材料基体内部的气体在减压的过程中膨胀而形成裂纹;二是在腐蚀过程中基体内部的填料与氟橡胶基体之间脱粘;三是在腐蚀过程中硫化氢与主链共轭双键反应,使密封材料的交联点被破坏。

This work was discussed on the sealing rubber used in opening blind plate at Pu Guang oil and gas field.We analyzed the changes of the appearance,mechanical properties,microstructure,and infrared spectra before and after the laboratory corrosion experiments with H2S/CO2 environment,and the corrosion mechanism on H2S/CO2 environment of the fast-opening blind plate sealing rubber was interpreted.The results show that three reasons mainly caused the severe loss of the mechanical properties of sealing rubber after corrosion： first,the cracks formed when the gas dissolved in the matrix during presurization expanded in the decompression process;second,during the corrosion progress,the fillers in the material separate with the rubber matrix;the third,the reaction of conjugated double bonds with H2S destroy the cross-linking point of the sealing rubber during the corrosion process.