Corrosion Property Testing of AFLAS Rubber under The Simulation modes of High Acid Gas Wells.

Abstract: Rubber sleeve is sealing component of underground packers, the rubber will occur corrosion or failure under the acid medium environment, which causes gas leak and leads to the security problems of wellbore. In the paper, corrosion testing was carried out to AFLAS rubber using HTHP autoclave in the harsh environment with the pressure 60MPa, temperature 175°C, test period 7 days and the compositions of the gas phase are 20vol% H2S, 5vol% CO2, 75vol% CH4. Comparing and analyzing the changes of properties in gas and liquid phase before and after testing, such as quality, volume, tensile properties, hardness, permanent deformation, etc. The experimental results show that AFLAS rubber in gas and liquid phase has no dissolution phenomenon; moreover, tensile properties were weakened, hardness decreased and permanent deformation increased. While bubbling of AFLAS rubber in gas phase was more serious than in liquid phase, the swelling was on the contrary. Although AFLAS rubber is a good kind of anti-acid medium rubber, its mechanical properties is weakened in harsh environment. Therefore, in order to improve the effective seal life of packers in corroded environment, the corrosion influence on packer rubber should be considered when it is designed and used in high sour gas fields. [Copyright &y& Elsevier]