Seal ring and bearing assembly

Claim 2

A SEAL ASSEMBLY COMPRISING TWO RING MEMBERS HAVING RADIALLY EXTENDING SURFACES IN SLIDING CONTACT WITH EACH OTHER, BOTH OF SAID FURFACES HAVING A HARDNESS ON THE MOHS SCALE OF AT LEAST ABOUT 7 AND AT LEAST ONE OF SAID SURFACES BEING OF MAGNESIA-ALUMINA SPINEL.

Claim 3

An assembly as set forth in claim 1, wherein both of said surfaces are of magnesia-alumina spinel.

Claim 4

An assembly as set forth in claim 1, wherein one of said surfaces is of alumina ceramic.

Claim 5

An assembly as set forth in claim 1, wherein each of said two members is a monolithic body of sintered magnesia-alumina spinel.

Claim 6

An assembly as set forth in claim 1, wherein one of said members is a monolithic body of sintered magnesia-alumina spinel and the other of said members is a body of alumina ceramic.

Claim 7

An assembly as set forth in claim 5, wherein said body of alumina ceramic contains at least about 95% by weight aluminum oxide.

Claim 8

An assembly as set forth in claim 1, wherein each of said surfaces has a surface finish not greater than 30 microinches (root mean square).

Claim 9

An assembly comprising a rotating shaft, a housing having an opening therethrough encircling the shaft, and a face type seal for preventing leakage of fluid between said shaft and housing opening, said seal comprising two axially adjacent rings encircling the shaft adjacent said opening, each of said rings having an annular end face, each said face rotatably bearing against the face of the other ring, one of said rings being connected to the shaft for rotation therewith and the other of said rings being held against rotation by the housing, the face of each of said rings having a hardness on the Mohs scale of at least about 7 and the face of at least one of said rings being of magnesia-alumina spinel.

Claim 10

An assembly comprising a rotating shaft, a housing having an opening therethrough encircling the shaft, and a face type seal for preventing leakage of fluid between said shaft and housing opening, said seal comprising two axially adjacent rings encircling the shaft adjacent said opening, each of said rings having an annular end face, each said face rotatably bearing against the face of the other ring, one of said rings being connected to the shaft for rotation therewith and the other of said rings being held against rotation by the housing, the face of each of said rings having a hardness on the Mohs scale of at least about 7 and the face of at least one of said rings being of magnesia-alumina spinel.

Claim 11

An assembly as set forth in claim 8, wherein each of said rings is a monolithic body of sintered magnesia-alumina spinel.

Claim 12

An assembly as set forth in claim 8, wherein one of said rings is a body of alumina ceramic.

Claim 13

A seal ring for use in combination with another ring to effect a face type seal, said seal ring having a radially extending face of magnesia-alumina spinel with a surface finish not greater than about 30 microinches (root mean square) for abutting rotative sliding engagement with said other ring.

Claim 14

A seal ring for use in combination with another ring to effect a face type seal, said seal ring having a radially extending face of magnesia-alumina spinel with a surface finish not greater than about 30 microinches (root mean square) for abutting rotative sliding engagement with said other ring.

Claim 15

A seal ring as set forth in claim 11, wherein said seal ring is a monolithic body of sintered magnesia-alumina spinel.