Magnetic seal system with internal cooling

An assembly comprising:

• a shaft;
• a support structure surrounding the shaft;
• and
• a magnetic seal system comprising
• an annular seal assembly including a ring sealingly mounted to a shaft to rotate therewith and slidingly axially displaceable along the shaft, and an annular seal supported by the ring,
• an annular magnet assembly non-rotatingly supported adjacent to and surrounding the shaft, the annular magnet assembly including an annular magnet positioned relative to the ring to exert a sufficient attracting force on the ring to biasingly displace the ring axially along the shaft into sealing contact with the annular magnet,
• a cooling fluid feeding conduit,
• a cooling fluid exhaust conduit distinct from the cooling fluid feeding conduit, and
• an annular cavity defined at least partially by or in a radially outer surface of the annular magnet, the annular cavity defining a hollow flow path entirely circumscribed by the annular magnet and the support structure, the flow path of the annular cavity being in fluid communication with the cooling fluid feeding conduit, and with the cooling fluid exhaust conduit, for circulation of cooling fluid in the annular cavity.

A method for cooling an annular magnet of a magnetic seal assembly sealing a gap between a shaft and a support structure, the method comprising:

• feeding cooling fluid to an annular cavity surrounding the annular magnet via a first conduit;
• circulating the cooling fluid in the annular cavity in a hollow flow path entirely circumscribed by the annular magnet and the support structure such that the cooling fluid flows directly against a radially outer surface of the annular magnet;
• and
• exhausting the cooling fluid via a second conduit distinct from the first conduit.