better sealing performance. The second concept be led to control the pressure in the seal, due to supply the compressed air having a constant flow rate and blow it into the sea water through under the lip of seal ring.
In case that the seal ring has unfortunately some damages and the sea water infiltrated or the oil leaked to the air chamber, it must be exhaustively collected to inboard. The third concept is achieved to collect the drain automatically inboard through the drain piping connected to the drain collection unit.
