27
06
Operation
Operator’s Manual 2009 Rev B p/n 2009
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 a normally 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 additional guidance.
Operation
1. Check the oil level in the sight glass of the
blower and make sure all fittings are tight.
2. Check the water injection system to make sure
water is available.
3. Operate the blower dry for a few minutes at no
load to check for correct rotation and smooth
operation.
4. Turn the water on and adjust flow 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-flow blowers with two-lobed,
plugged rotors. Always orient the system with
the blower intake at the top and discharge at the
bottom.
CAUTION
!
Water injection can cause lime build-up on
rotors. Check water supply for hardness. The
use of water softeners, other chemicals, or
distilled water may be necessary to prevent
or remove this build-up. However, due to
the wide variations in mineral content, pH,
and chemical content of water that can be
injected, Tuthill Vacuum & Blower Systems
cannot be responsible for damage which
may result should this build-up occur. Units
should be inspected regularly to determine
any problems.
For liquid injection other than water, consult
the factory.
RECOMMENDED SHUTDOWN
PROCEDURE TO MINIMIZE RISK OF
FREEZING OR CORROSION
When an air piping system has high humidity or
moisture, water condensation can occur after
the blower is shut down and it begins to cool.
Condensation creates an environment favorable
to corrosion of the iron internal surfaces and to
ice formation in cold weather. Both conditions can
close the operating clearances, causing the blower
to fail upon future start-up.
The following shutdown procedure minimizes
the risk of moisture condensation, corrosion, and
freezing.
