Model 600-PO - Steam Safety Valve

Product Brand: Target Rock

A solid history of reliability in hundreds of thousands of hours of reactor operation.

Target Rock has been manufacturing ASME Section III pilot-operated safety valves for commercial nuclear power plants since 1967. The heart of our technology is a special bellows machined out of solid bar stock that has nhundreds of thousands of hours of reliable reactor operation. This unique piece of machining is used as a pressure sensor to actuate the valve at the set pressure.

The advantage of piloted valves is they are pressure seated; the higher the pressure the greater the seating force and these valves are known for their tight seating performance.

SizeMain steam safety relief valve:
  • 6 in. (DN150) to 10 in (DN250)
Pressurizer safety valve
  • 6 in. (DN150) to 6 in (DN150)
ApplicationsPressurizer safety valve
Main steam safety/safety-relief valve
Quality ClassASME III Class 1, ASME QME-1

Principles of Operation

Boiling water reactor solution

This technology is currently installed in boiling water reactors worldwide in the main steam safety relief valve and in pressurized water reactors in the pressurizer safety valve application. For applications where both safety and relief functionality are required, Target Rock offers an optional actuator using our solenoid valve technology.

Recommended applications

  • Pressurizer safety valve
  • Main steam safety valve
  • Main steam safety relief valve
Differential Pressure MechanismUnaffected by change to state of process fluids
Chatter FreeNo chatter when valve set on steam passes water
StabilityUnaffected by two-phase flow
Historic SolutionDeveloped in the 1960s
DependableHas never failed in thousands of reactor hours of service
SimpleSimplified valve design