Pressure maintaining device and method for pressurized water reactors

Claim 2

Method of automatically maintaining pressure in a pressuremaintaining device of a pressurized water reactor which comprises spraying into a steam chamber of the pressure maintaining device, in response to a respective stimulus denoting a pressure increase in the pressure-maintaining device, at least a partial flow of hot water flowing in a pressurized water line from the reactor to a steam generator, and additionally spraying into the steam chamber continuously and constantly a lesser flow of cold water flowing in a line from the steam generator back to the reactor.

Claim 3

Method according to claim 1 wherein the stimulus is the change in pressure per se.

Claim 4

Method according to claim 1 wherein the stimulus is a change in power output of the reactor.

Claim 5

System for carrying out the method of automatically maintaining pressure in a pressure-maintaining device according to claim 1 comprising an equalizing line branching from the hot side of a primary circulatory loop of a pressurized water reactor and connected to the pressure-maintaining device, throttling means and at least one check valve connected in parallel in said equalizing line upstream of the pressure-maintaining device, a first spray line branching from said equalizing line upstream of said throttling means, said line having a check-valve connected therein and terminating in a steam chamber forming part of the pressure-maintaining device, and a second spray line directly leading from the cold side of the primary circulatory loop to the steam chamber.

Claim 6

System according to claim 4 including at least two check valves connected in parallel in said equalizing line, said throttling means comprising a throttle opening formed within said check valves.

Claim 7

System for carrying out the method of automatically maintaining pressure in a pressure-maintaining device according to claim 1 comprising an equalizing line branching from the hot side of a primary circulatory loop of a pressurized water reactor, said equalizing line extending into and along substantially the entire axial length of the pressure-maintaining device, first spray means provided for said equalizing line, in the vicinity of an upper steam chamber of the pressure-maintaining device, said first spray means being operatively connected to the hot side of the primary circulatory loop, and second spray means located within said pressure-maintaining device and connected to the cold side of the primary circulatory loop, said equalizing line being formed, in the vicinity of a lower water chamber of the pressure-maintaining device, with a water outlet opening automatically closeable in response to pressure increase.

Claim 8

System according to claim 6 wherein said spray means comprises spray openings formed in said equalizing line.

Claim 9

System according to claim 6 wherein said spray means are in the form of spray nozzles mounted on said equalizing line.

Claim 10

System according to claim 6 wherein the pressure-maintaining device in the vicinity of the water chamber thereof and of a lower region of the steam chamber thereof has a smaller diameter than the diameter of the upper region of the steam chamber thereof.

Claim 11

System according to claim 6 including a continuous spray line terminating in the water chamber of the pressure-maintaining device.