Tuthill PD Plus - Water-Injected Blowers; Operation; Shutdown

Manual 2007 Rev B p/n 2007
26
06
Operation
Inject the mixture on the inlet side through a valve
set to feed 1 gal (3.8 L) of mixture in 15 – 20
minutes. On blowers that are regularly fl ushed,
fl ushing once a week is suffi cient. If the blower is
dirty, fl ush it daily until the hard build-up is removed
and then move to a weekly cycle. In very dirty gas
installations, vary the cycle to meet the demand.
FLUSHING
FLUID
CONTROL
VALVE
Figure 1-1 – Flushing
WATER-INJECTED BLOWERS
Water injected into the inlet of a blower operating
on vacuum service will cool the blower. The water
absorbs the heat of compression as it passes
through the blower along with the air/gas being
compressed. A blower cooled in this manner can
operate safely at higher vacuums or higher inlet
temperatures than an uncooled blower.
The amount of water required depends on the
inlet air/gas temperature, inlet vacuum, water
temperature, and maximum discharge temperature
desired. Check with the factory or sales
representative for more guidance.
Operation
1. Check the oil level in the sight glass of the
blower and make sure all fi ttings are tight.
2. Check the water injection system to make sure
water is available.
3. Operate the blower dry for 3 minutes at no
load to check for correct rotation and smooth
operation.
4. Turn the water on and adjust fl ow as
recommended for the individual blower. Make
sure the water discharges freely from the outlet
piping.
5. Apply vacuum and observe operation at the
desired inlet condition.
Shutdown
It is possible to shut down the blower for brief
periods by relieving the inlet vacuum, shutting off
the water, and then stopping the blower.
To avoid rusting during a slightly longer shutdown
period, operate the blower under a partial vacuum
without the water injection, allowing the blower to
heat within safe limits. The heat will tend to drive
off residual moisture.
For extended shutdown, oil may be injected into
the inlet of the heated blower just prior to shutting
down the blower. The oil will provide a protective
coating on the internal components. Make sure the
water is completely shut off after shutdown.
Special coatings or platings are available to
minimize rusting or corrosion in applications where
blowers can remain wet.
Always use vertical-fl ow blowers with two-lobed,
plugged rotors. Always orient system with the
blower intake at the top and discharge at the
bottom.