The Type 670 is an all-Alloy C-276 rotating bellows seal, providing high strength and excellent corrosion resistance. It is extremely durable in applications where temperature and media (fluid) result in an aggressive environment. The Type 670 has been tested per API-682 Type B seals for low-temperature refinery services. Other common applications include acids, caustics, amines and products with H2S, such as sour water and sour hydrocarbons. The Type 670 can be shaft-mounted or is available in both dual and single cartridge arrangements. In dual seal arrangements a non-pressurized buffer or pressurized barrier fluid can be used. A pumping ring recirculates barrier fluid, assuring cooler operating temperatures and extended reliable performance.