Search results
Results From The WOW.Com Content Network
The actuation of these valves depressurizes the reactor vessel and allows lower pressure coolant injection systems to function, which have very large capacities in comparison to the high pressure systems. Some depressurization systems are automatic in function, while others may require operators to manually activate them.
Computer generated view of an EPR power station Reactor pressure vessel of the EPR. The EPR is a Generation III+ pressurised water reactor design. It has been designed and developed mainly by Framatome (part of Areva between 2001 and 2017) and Électricité de France (EDF) in France, and by Siemens in Germany. [1]
In the event that pressurizer pressure exceeds a certain maximum, there is a relief valve called the pilot-operated relief valve (PORV) on top of the pressurizer which opens to allow steam from the steam bubble to leave the pressurizer in order to reduce the pressure in the pressurizer. This steam is routed to a large tank (or tanks) in the ...
Passive nuclear safety is a design approach for safety features, implemented in a nuclear reactor, that does not require any active intervention on the part of the operator or electrical/electronic feedback in order to bring the reactor to a safe shutdown state, in the event of a particular type of emergency (usually overheating resulting from a loss of coolant or loss of coolant flow).
Its function is distinct from that of pressure relief valves, which are passive devices opening if pressure reaches a value above the process safety trip, but still below the design pressure of the equipment. Relief valves complement the PSD. A process plant is typically divided into isolatable sections by emergency shutdown valves (ESDVs).
The AP1000 design traces its history to two previous designs, the AP600 and the System 80.. The System 80 design was created by Combustion Engineering and featured a two-loop cooling system with a single steam generator paired with two reactor coolant pumps in each loop that makes it simpler and less expensive than systems which pair a single reactor coolant pump with a steam generator in each ...
The timing of these valves to stroke closed is a component of each plant's safety analysis and failure to close in the analyzed time is a reportable event. Examples of isolation groups include the main steamlines, the reactor water cleanup system, the reactor core isolation cooling (RCIC) system, shutdown cooling, and the residual heat removal ...
A typical RPV. Russian Soviet era RBMK reactors have each fuel assembly enclosed in an individual 8 cm diameter pipe rather than having a pressure vessel. Whilst most power reactors do have a pressure vessel, they are generally classified by the type of coolant rather than by the configuration of the vessel used to contain the coolant.