B K Jagan and Co Stainless Steel Thermodynamic Steam Trap (3/4 Inch) Globe Valves

The steam trap works on the pressure difference above and below the disc. The incoming pressure causes the disc to be lifted from its seat. The high velocity of the flashing condensate creates low pressure beneath the disc, at the same time pressure builds up in the chamber which forces the disc onto the seat. Now the condensate in the chamber reduces the pressure and when it is less than the inlet pressure, the disc lifts. This cycle repeats again and again.