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2.3 Air Piping
¡
Plan B (using auto valve)
[2] Plan B (Automatic air elimination with auto valve
installed)
1 Regardless of the occurrence of air locking, con-
tinuous automatic air elimination is executed in
the entire system. For example, the air elimina-
tion process is activated every 2 minutes after the
start-up of the pump by opening the auto valve
for 10 seconds.
Note 1: Some filters have diameters too small for air
elimination. Take the diameter into consid-
eration when selecting a filter.
Note 2: Determine the open period of the auto valve
on the basis of the system performance.
2 If the conditions under which bubbles are min-
gled remain the same, an air elimination tech-
nique which fits well with such conditions may
be applicable. For example, if bubbles are gener-
ated only when feeding H
2
O
2
, open the auto valve
to carry out air elimination only when H
2
O
2
is fed.
3 Another technique is to install an air detection
sensor in the suction port area, so that the auto
valve is automatically opened by a signal sent out
from the sensor and the air elimination operation
is executed.
•
Installing another air detection sensor on the
discharge side is effective in preventing air
from entering in the event of bellows damage.
H
2
O
2
,O
3
,H
2
O
Air elimination line
Auto valve
Filter
Pump
Overflow tank
Heater
Reaction
tank
P
CAUTION
™
Any supplied air must be instrumentation air which is clean and free from moisture and dust. Water, oil,
or dust in the supplied air may lower the performance of the pump.
™
The following troubles may occur with FS type pumps if the air supply piping is long and narrow.
a. The bellows may be deformed inwardly due to remaining compressed air that is not efficiently
released out of the pump air chamber.
b. Discharge may be reduced due to pump stroke speed slowdown.
Complete air piping in accordance with the sample arrangement
shown on the next page.
