PUMP FOR TRANSFERRING LIQUID IN HIGH-PRESSURE CIRCUIT Russian patent published in 2002 - IPC

FIELD: nuclear power plants. SUBSTANCE: invention relates to design of bearing units of pumps, mainly main circulating pumps of first circuit of cooler. Proposed pump has shaft with flange, lower radial bearing and radial-axial bearing which accommodates in its housing upper radial bearing and double-side axial (thrust) bearing. Thrust disks on the latter are secured on flange. Thrust blocks are furnished with lever equalizing systems. Pump has cooling and radial-axial bearing lubricating circuit with vertical expansion chamber. Plate spring is installed under lower holder of axial bearing. Spring force, with axial bearing operating on upper blocks is equal to 3-6-fold values of weight of holder with lever equalizing system and thrust blocks. Lower part of housing of radial-axial bearing is made in form of cylindrical support with apertures. Expansion chamber in its upper parties communicated with pressure- head tank through monotonically rising pipeline. Pressure-head tank communicates with atmosphere. Multiple-start threads of opposite hand of helix are made on cylindrical surface of lower part of flange and on surface of bushing enclosing cylindrical surface. Said threads form labyrinth-screw pump. EFFECT: reduced vibration of thrust bearing, prevention of action of handled medium onto housing and elements of cooling and lubricating circuit. 2 dwg