172-65378MA-03 (GP10F PowerTrap) 23 Apr 2019
12
Explanation for Overflow Piping for Open Systems
1) If flash steam can be discharged from overflow pipe
Install overflow pipe and vent pipe separately.
2) If flash steam should not be released from overflow pipe (prevent flash steam
release)
Install overflow pipe and vent pipe separately. For overflow pipe, install loop
seal (approx. 300 mm (12 in)). Flash steam release from overflow pipe can be
prevented since water always accumulates at loop seal. Piping size should be
the same or larger than condensate inlet pipe.
NOTE: • There is a possibility of rust becoming clogged and/or corrosion since
water always present in the loop seal. The possibility is greater if the
piping diameter is too small (generally 25 mm (1 in) or smaller).
• If the loop seal becomes clogged, hot overflow water will blow from
vent pipe. Make sure to install vent pipe to lead to a safe place
• Do not install loop seal on the vent pipe
Contact TLV if neither 1) nor 2) above can be installed.
(8) Velocity at Outlet Piping
The PowerTrap uses the motive medium supply pressure to push the pumped
medium out of the trap.
•
The GP10F can discharge approximately 30 liters (7.9 gallons) of pumped
medium for each discharge operation.
•
The amount of time required for each discharge operation will be between 3 and
30 seconds, depending on the back pressure and the motive medium pressure.
This means that the instantaneous flow through the pumped medium outlet pipe
during the discharge operation is between 3.6 and 36 metric tonnes (950 and
9500 gallons) per hour.
•
When a flowmeter is to be installed in the pumped medium outlet piping, it should
be selected to reflect the intermittent operation and should be sized to
accommodate the maximum and minimum instantaneous flow. Contact TLV for
details.
Sizing the Condensate Receiver/Reservoir
When selecting the receiver/reservoir for the PowerTrap, select from among the
following 3 conditions:
(1) When large quantities of flash steam are involved
(For open systems using steam)
a) Determine the amount of flash steam:
Amount of flash steam Fs = Q
×
(hd’
−
hh’)/r
Fs : amount of flash steam (kg/h) (lb/h)
Q : amount of condensate (kg/h) (lb/h)
hd’ : specific enthalpy (kJ/kg) (Btu/lb) of saturated condensate at
condensate inlet set pressure (P
1
)
hh’ : specific enthalpy (kJ/kg) (Btu/lb) of saturated condensate at
Receiver
P
1
P
2
Flash Steam
Condensate
P
1
2
