Engineers say seals made with Parker Hannifin's carboxylated HNBR sealing material operate better in extremely high temperatures and with highly abrasive fluids than other nitriles. A Canadian oil-well tooling company is using the material as the packing element around casing and piping in oil wells. The well fluids are corrosive and eat the casings, experts say. Plus, the farther into the well hole the tools go, the higher the temperatures they meet. The holes can go down to 10,000 ft. The XHBNR works in temperatures up to 300F and has a tensile strength of 5000 psi. It also resists hydrogen sulfide.