Today, with the dearth of easy-to-reach reservoirs, formation evaluation is being conducted in difficult-to-reach and harsh environments. Key challenges in the formation evaluation of these new reservoirs include extremely high pressure and high temperature(HPHT)and associated sealing issues.
Two major material properties are required for sealing. One is mechanical strength at high temperature, which determines maximum sealing pressure, and the other is chemical resistance, which determines the sealing lifetime.
We are using multiwalletd carbon nanotube(MWNT)-polymer nanocomposites in the development of an HPHT sealing system. We confirmed mechanical strength and chemical resistance of the new sealing system in the laboratory and in oilfields around the world. The sealing system has been successfully commercialized in the oilfield industry.
This paper investigates chemical resistance of the sealing system. Resistance to mud, water, and oil at high temperature determines the sealing lifetime, the operation rating, and the cost of exploration and exploitation activity and improves safety.