Whereas many shaft seals are designed to be installed onto a running surface, a unitized seal is a shaft seal that incorporates a running surface into the seal design. Also known as cassette seals, unitized seals are commonly used when the actual shaft surface lacks an acceptable finish (due, for example, to prior damage or improper metal finishing).

Some unitized seals include both a metal sleeve that serves as the contact surface for the primary sealing lip and a vertical flange against which an axial dirt lip can seal. Because unitized seals come with their own sealing surface(s), they effectively take the burden of providing these surfaces off of the end-user.

Figure 78 shows a unitized seal with a flange. Figure 79 shows a unitized seal with a ribbed rubber O.D., and Figure 80 shows a unitized seal with a ribbed rubber O.D. and a full rubber interior. All three designs feature a vertical element to facilitate axial sealing.

NON-STANDARD DESIGNS MAIN PAGE