Double safety valve with 3 way valve for service

Safety valves feature a piston and a calibration spring. When the system pressure reaches the set pressure, the valve opens and relieves the pressure and then closes again. They can be single or double type when we mount two safety valves on one three-way valve. The second type is particularly interesting because it allows one valve to be extracted to be rechecked, while the other remains connected to the system, protecting it.