172-65460MA-04 (JH7.5R-X) 20 Oct 2020
5
Operation
Principles of air and condensate discharge:
1. Start-up Air and Cold Condensate Discharge
At start-up, before steam is supplied, the trap is
cold so the X-element is contracted and the air vent
valve (A) is open. This allows for the rapid
discharge of air through the air vent valve (A) and
cold condensate through the orifice (B), when
steam is first supplied to the system.
2. Condensate Discharge
After the discharge of initial air and cold condensate,
the heat of the inflowing steam and condensate
causes the X-element to expand, closing the air vent
valve (A). The rising condensate level causes the
float to rise due to buoyancy, opening the orifice (B)
and allowing condensate to be discharged.
3. Hot Air Discharge
Should hot air flow into the trap with the steam
during normal operation, the temperature of the X-
element drops, causing it to momentarily contract
and open the air vent valve (A), which allows for the
rapid discharge of the air. After the air is discharged
and steam contacts the X-element, the temperature
will increase causeing the air vent valve (A) to close
4. Discharge of Large Quantities of Condensate
Increases in the condensate inflow rate cause the
condensate level in the trap to rise. The float
consequently rises and enlarges the opening of the
orifice (B), allowing more condensate to be
discharged. If condensate flows in at a faster rate
than it discharges through the orifice (B), the
temperature of the X-element drops, causing it to
momentarily contract and open the air vent valve (A),
which allows for the rapid discharge of the
condensate through both (A) and (B). In this manner,
continuous condensate discharge occurs while the
opening size of the orifice varies depending on the
condensate flow rate.
5. Closed Position
When the condensate flow rate decreases, the X-
element expands due to the heat of the steam,
closing the air vent valve (A). In addition, the float
falls as condensate is discharged, closing off the
orifice (B). A water seal is maintained at all times
over the orifice (B) to prevent steam loss.
Air
Steam
Condensate
