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.
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