Siemens Aktiengesellschaft

Kraftwerk Union Aktiengesellschaft

Pramod Batheja

Peter Rau

Werner Meier

Werner Leidemann

Hermann Kumpf

Claus Goetzmann

Manfred Hrlein

Otto Gremm

Eduard Weber

Jurgen Wirkner

A secondary-side residual-heat removal system for a pressurized-water reactor removes residual heat through a secondary side of a steam generator in certain modes of operation and malfunction. For this purpose, the respective steam generator has a connection on a live-steam and feed-water side to a secondary side of a safety condenser. The connection on the feed-water side is led to a supply connection of a swirl or vortex chamber valve having a control connection which is connected to a feed-water line part on the pressure side, with a downgradient from a main feed-water pump, and the swirl or vortex chamber valve has an outlet which opens out into a feed-water inflow space of the steam generator. A tertiary side of the safety condenser is fed from a water reservoir disposed at a geodetically higher level. The steam being generated is discharged into the atmosphere through a blowing-off line, with a separating device if appropriate. Due to the geodetically higher configuration of the safety condenser in comparison with the steam generator, the energy transmission on the secondary side takes place by natural circulation.

Secondary-side residual-heat removal system for pressurized-water

A hydraulic control rod drive for a nuclear reactor, with a a reactor plenum enclosing the drive, comprises first and second hollow bodies together forming a cylinder and a hollow piston. Working fluid is supplied through one of the hollow bodies. The first hollow body is stationary and the second hollow body is disposed coaxially around the first hollow body. The two hollow bodies define an annular gap therebetween so as to allow axial reciprocating movement of the second hollow body, which forms a carrier body for control elements of the control rod. The second hollow body can be lifted, lowered or suspended by feeding working fluid. A portion of the fluid is removed from the inner space via a throttle passage. A positional measurement system determines the relative displacement of the second hollow body by measuring an ultrasonic measurement path. The system includes an ultrasound reflector and an ultrasonic transducer rigidly mounted remote from the ultrasound reflector. Provisions are made for venting the inner space through venting channels which open into the reactor plenum at a security distance from the measurement path so as not to adversely affect the ultrasonic measurement.

Hydraulic control rod drive for a nuclear reactor

A hydraulic control rod drive for a water-cooled nuclear reactor includes a control valve assembly outside the reactor pressure vessel for influencing the fluid quantity on the pressure side of a fluid pump assembly for adjusting control rods in raising and lowering directions and to maintain a control rod position. A control valve assembly includes the following control branches for actuating each of the control rods: a holding branch connected between a pressure line and a pressure side of a piston/cylinder system, a first fluid throttle and a bypass fluid throttle upstream thereof relative to a drop of the first fluid throttle for discharging into a drain, the first fluid throttle and the bypass fluid throttle having throttle cross sections allowing a fluid flow therethrough sufficient to hold a given control rod in a given position with the fluid pump assembly running; a raising branch connected to the holding branch upstream and downstream of the first fluid throttle, and a series circuit having a raising valve assembly and a second fluid throttle; and a lowering branch connected to the holding branch downstream of the first fluid throttle relative to the drop of the first fluid throttle and discharging into a cooling water reservoir, and a series circuit of a lowering valve and a third fluid throttle. A device is also provided for automatically opening the lowering valve in the lowering branch if the raising valve in the raising branch sticks in an open position.

Hydraulic control for rod drive for water-cooled nuclear reactors,

Liquid-cooled nuclear reactor having a reactor pressure vessel and a reactor core of fuel assemblies received therein, the fuel assemblies being grouped into core cells each having a control rod containing absorber material and connected to a drive mechanism, including a sheetmetal shaft associated with the core cells, respectively, and extending beyond the length of the reactor core by a length at least equal to that of the respective control rod and having a cross section substantially equal to that of the respective core cell, the sheetmetal shaft being formed with longitudinal channels through which the fuel assemblies are loadable and unloadable.

Liquid-cooled nuclear reactor especially a boiling-water reactor

Growing community of inventors

Erlangen, Germany

Pramod Batheja