13
05
Installation
Operator’s Manual 2009 Rev B p/n 2009
Soft Foot
Soft foot is a condition in which one of the blower
feet does not sit flat on the base. Soft foot is usually
due to irregularities in the surface to which the
blower is mounted. When the bolt on the foot is
tightened, a slight distortion occurs that can affect
bearing and seal life as well as cause premature
internal contact between the rotors and the housing.
ANGULAR
SOFT FOOT
PARALLEL
SOFT FOOT
Figure 5-2 – Illustrations of Soft Foot
1. Place the blower on the base.
2. Check each foot for gaps between the foot and
base (soft foot). Shim as necessary to fill gap
within 0.002 in. (0.05 mm).
Figure 5-2
shows the two most common types
of soft foot conditions. If either type is present
at a measurement of more than 0.003 in.
(0.076 mm), the blower may fail prematurely.
3. Tighten all bolts.
4. Mount a dial indicator on the base contacting
one foot at 12 o’clock position.
5. Loosen the bolt on that foot. Observe indicator
travel and add shims as needed to reduce
“spring” to less than 0.002 in. (0.05 mm).
Repeat steps 4 and 5 on the remaining feet.
SAFETY
Tuthill Vacuum & Blower Systems recommends
the use of relief valves to protect against excessive
pressure or vacuum conditions. Test these valves
at initial start-up to be sure they are properly
adjusted to relieve at or below the maximum
pressure differential rating of the blower.
DANGER
!
It is the responsibility of the
installer to assure that proper
guarding is in place and
compliant with all applicable
regulatory requirements.
DANGER
!
Internal and external rotating
parts of the blower and driving
equipment can produce
serious physical injuries. The
blower should never be run
with the inlet or discharge
piping removed. If it becomes
necessary to inspect the
rotating parts of the blower or
to change V-belts, be absolutely
sure that all power to the motor
controls has been shut off, the
motor controls are locked out,
and properly tagged before
proceeding.
