172-65464MA-02 (JH8R-B) 18 Nov 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
system is cold and the bimetal plate is
contracted (flexed downward), keeping the air
vent valve (A) open. When steam is first
supplied to the system, air is discharged
through the vent (A) while cold condensate is
discharged through the orifice (B).
2. Condensate Discharge
After the discharge of initial air and cold
condensate, the heat of the inflowing steam and
condensate cause the bimetal plate to flex
upward, closing the air vent valve (A). The
inflowing condensate causes the float to rise
due to buoyancy, opening the orifice (B) and
allowing condensate to be discharged. The air
vent valve will remain closed throughout normal
operation due to the high operating
temperatures.
3. 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.
In this manner, continuous condensate
discharge occurs with the orifice opening size
varying depending on the condensate flow rate.
4. Closed Position
When the condensate flow rate decreases, the
float falls, closing off the orifice opening (B). A
water seal is maintained at all times over the
orifice (B) to prevent steam loss.
Air
Steam
Condensate
