METHOD FOR OPERATING LIQUID PRESSURIZING PUMP AND MECHANICAL SEAL THEREOF

PROBLEM TO BE SOLVED: To provide a method for operation for a liquid pressurizing pump capable of further reducing wear of a seal ring. SOLUTION: A control device 42 determines based on displacement measurement value of displacement detectors 43, 44 whether a gap between a stationary seal ring 16 and a rotary seal ring 17 of a first axial seal part 15 is under an externally expanding condition where cooling water easily enters or an internally expanding condition where cooling water does not easily enter. A control device 42 drops temperature of purge water supplied to a first seal chamber 21 by controlling a cooler 29 when the gap is under the internally expanding condition. The gap of the first axial seal part 15 gets under the externally expanding condition and wear of the seal ring is reduced. After temperature of purge water drops to lower limit temperature, pressure of an annular gap 26 is dropped by controlling a pressure adjusting valve 48. Consequently, wear is further reduced. COPYRIGHT: (C)2009,JPO&INPIT