The minimum pressure required to produce flow through a valve.
Duty Cycle:
100% duty cycle is defined as continuous operation without any damage occurring. For intermittent duty cycle (<100%), alternate energized and de-energized state at regular intervals to allow the valve to completely cool down to room temperature.
F = active concentration / total concentration
Flow Patterns:
A diagram showing how flow can be directed using a particular valve. (See the "Flow Patterns" box below for further explanation.)
Normally Closed:
Valve stays closed in de-energized state; opens when energized.
Normally Open:
Valve stays open in de-energized state; closes when energized.
Pressure Differential or Pressure Drop:
The difference between the inlet and the outlet pressure through a valve. The outlet pressure is lower than the inlet pressure due to the restriction caused by the valve.
Three-Way Valve:
Has three ports. Depending on the particular valve, all three ports may be open, two ports may be open, or all ports may be closed.
Two-Way Valve:
Has a single inlet port and a single outlet port. Brass Valves Factory Selection Guide