Tuf-Lite III
®
5000 Series Installation Manual Page 4 of 8
May 2006
Rotate blade in clamp until digital protractor shows specified
pitch angle to /-0.2°. Fan pitch angle is shown on fan
specification sheet for design duty. After desired pitch angle is set,
raise and lower end of fan blade and find midpoint of blade travel.
Hold blade at the midpoint. Pull blade outward so that the blade
neck flange rests against the back of the blade clamps. Push blade
to the right to remove all slack.
Use torque wrench to tighten clamp bolts to 100 ft-lb (lubri-
cated) or 125 ft-lb (dry). Recheck pitch setting. Blade must be
set /-0.2° of desired pitch angle. Tighten clamp bolts
evenly.
DO NOT OVER-TORQUE CLAMP BOLTS.
When bolts are tightened, hold a pencil against top end of blade
and mark the level onto a fixed object, such as a pole or the
fan ring.
Install remaining blades at same place as first blade, following
the instructions above. After tightening bolts, mark top end of
each blade in same place first blade was marked. If marks differ
by 1” or more, adjust blade.
CHECK TRACK
After fan is installed in fan stack cylinder ring, outline top side
of each blade onto fan stack cylinder ring with a marker (See
Figure 5). The difference between levels of highest and lowest
outlines should not be more than 1”. Correct blade track by
loosening clamp bolts and adjusting blade to match track of other
blades. Retighten bolts and recheck track and pitch angle set-
ting. Retighten blade clamp bolts to recommended standard of
100 ft-lb (lubricated) or 125 ft-lb (dry) torque.
SEAL DISC ASSEMBLY & INSTALLATION
Install self adhesive rubber gaskets on both flanges of one seal
disc half. Bolt two halves of seal disc together, using 3/8” NC
bolts, flat washer, lock washer, and nut. Torque to 15 ft-lb
(lubricated) and 20 ft-lb (dry).
Install 3/8” NC bolts at six (6) places on top hub plate (See
Figure 6). Threaded portion of bolts must be pointing up to
mount seal disc. Install lock washer, nut, and flat washer on
each bolt. Tighten 3/8” NC nuts to 15 ft-lb (lubricated) and 20
ft-lb (dry).
NOTE: 22B & 24B fans pitched above 10½ and 26B - 30B fans
pitched above 19½ require a different mounting arrangement.
Refer to instructions included with seal disc for details.
Locate the six (6) mounting holes in seal disc and install over
the six (6) bolts pointing up on upper hub plate. If difficulty is
encountered, loosen bolts on seal flanges until seal disc can be
mounted, then retighten to 15 ft-lb (lubricated) or 20 ft-lb (dry).
NOTE
: The purpose of the seal disc is to prevent hot air from
recirculating back down through the hub, increasing efficiency.
Figure 5
Figure 6
