Extrusion resistance and high-pressure sealing performance of hydrogenated nitrile-butadiene rubber (HNBR)

摘要

The correlation between critical tear pressure and extrusion gap is of great importance for mechanical design of elastomer seals for oil and gas tools for high pressure high temperature (HPHT) applications. In this study, we first investigated the relationship between extrusion gap and extrusion resistance of two grades of HNBR elastomers utilizing a modified extrusion resistance test fixture with different extrusion gaps. Other basic properties such as hardness, modulus and creep resistance of the above two elastomers were also studied for better understanding the effect of these basic properties on extrusion resistance. With the combination of the relationship between extrusion resistance and extrusion gap, and the critical tear pressure measured based on API high pressure testing, the correlation between critical tear pressure and extrusion gap was then obtained. The test method is simple, and the archived correlation result is reasonable when compared with the literature.