Impulse Steam Trap - How It Works
- The main valve has a hole in the center called the “control orifice”;
condensate below saturation when entering into the orifice above the valve
is flashing and reducing the pressure in the chamber, allowing the valve
to open. The pressure drops in the chamber to 86%, or as low as 65%,
depending on the temperature of the water.
- When the condensate is within 30 degrees F of steam temperature, the chamber
pressure reaches or exceeds, 86% or as high as 95% of inlet pressure, and
the valve closes. In other words, high temperature condensate causes
intense flashing which closes the valve, stopping the discharge of hot water
except the amount that can flow through the center orifice.
This trap is suitable for draining saturated steam mains, except that at
all times steam is discharged through the control orifice, causing great losses
and difficulties in operation, deaireating tank and other auxiliary equipment.