Drive adjustment, Bearing lubrication, Warning – Twin City Tubeaxial, Vaneaxial, & Duct Fans ES-191 User Manual
Page 2: Figure 2. ball bearing relubrication schedule
2
Twin City Engineering Supplement ES-191
that dust does not enter the bearings. Check sheaves
for wear. Excessive slippage of belts on sheaves can
cause wear and vibration. Replace worn sheaves with
new ones. Carefully align sheaves to avoid premature
sheave failure.
Inspect the belts for wear. If fraying or other wear
is observed to be mostly on one side of the belts, the
drives may be misaligned. Reinstall the drives according
to the following instructions:
1. Slip (do not pound) the proper sheave onto its cor-
responding shaft.
Caution: Reversing the sheaves (plac-
ing the fan sheave on the motor shaft) can overspeed the
wheel and cause structural failure.
2. Align sheaves with a
straightedge
extended
along the sheaves, just
making contact on the
outside perimeters of both
sheaves. (See Figure 1.)
3. Tighten sheave bolts.
4. Adjust the motor posi-
tion to obtain slack. Install
and tighten belts. Use a
matched set of belts. Using
a pry will damage belts.
Never use belt dressing on
any belts.
5. Tighten belts to proper belt tension. Ideal tension is
just enough so that the belts do not slip under peak
load. Recheck sheave alignment.
6. New belts require a break-in period of operation so
recheck the belt tension after a few days of operation.
7. When replacing belts replace the entire set and follow
the procedure above.
Drive Adjustment
On small fans, the belt tension is adjusted by loosen-
ing the four nuts on top of the motor plate and turning
the four nuts underneath the motor plate to achieve the
proper belt tension. Tighten the top four nuts to hold the
motor plate in place. Care should be taken to maintain
drive alignment as described above. Large fans use a
pivoting motor mounting plate. Adjust the belt tension by
loosening the two nuts and bolts on the pivoting side of
the motor plate, and the nuts that hold the eyebolts to
the motor plate on the other side. Turn the nuts on the
eyebolts that are underneath the motor plate to achieve
the proper belt tension and then tighten the top nuts
and the pivot side nuts and bolts. When tightening the
nuts that are on the eyebolts, take care to maintain
proper drive alignment.
Positioning the motor plate at too high of an angle
may result in the belts rubbing against the belt tube
inside the fan. The motor plate pivot bolt must be
moved up or down to the next hole to keep the drives
centered in the belt tube. The ideal motor plate position
is perpendicular to the belt tube centerline.
Bearing Lubrication
Proper lubrication of belt drive bearings helps assure
maximum bearing life. All fans are equipped with decals
indicating relubrication intervals for normal operating
conditions. However, conditions at every installation are
different and the frequency of relubrication should be
established accordingly. Figure 2 shows the relubrication
schedule for ball bearings. Figure 3 shows the relubri-
cation schedule for solid pillow block spherical roller
bearings.
Figure 1.
Sheave Alignment
Lubrication intervals should be doubled on fans with
vertical shafts.
On high moisture applications, the relubrication fre-
quency may need to be doubled or tripled to adequately
protect the bearings. Carefully replace the joint sealant
under the bearing access cover whenever the bearings
on high moisture fans are serviced.
Straightedge
WARNING
1. This equipment must not be operated without proper guarding of
all moving parts. While performing maintenance be sure remote
power switches are locked off. See AMCA Publication 410 for
recommended safety practices.
2. Before starting: Check all setscrews for tightness, and rotate wheel
by hand to make sure it has not moved in transit.
*Suggested initial greasing interval: Rotate bearings during relubrica-
tion where good safety practice permits until some purging occurs at
seals. Adjust lubrication frequency depending on condition of purged
grease. Hours of operation, temperature, and surrounding conditions
will affect the relubrication frequency required.
1. Lubricate with a high quality NLGI No. 2 or No. 3 multipurpose
ball bearing grease having rust inhibitors and antioxidant additives.
Some greases having these properties are:
Shell - Gadus S2 V100 2 Mobil - Mobilith AW2/Mobilith SHC100
Gulf - Gulfcrown No. 2
American - Rykon Premium 2
2. Lubricate bearings prior to extended shutdown or storage and
rotate shaft monthly to aid corrosion protection.
Figure 2. Ball Bearing Relubrication Schedule
Relubrication Schedule (Months)*
Ball Bearing Pillow Blocks
Speed (RPM)
500 1000 1500 2000 2500 3000 3500 4000 4500
Shaft DIA
1
⁄
2
" thru 1
11
⁄
16
"
6
6
5
3
3
2
2
2
1
1
15
⁄
16
" thru 2
7
⁄
16
"
6
5
4
2
2
1
1
1
1
2
11
⁄
16
" thru 2
15
⁄
16
"
5
4
3
2
1
1
1
3
7
⁄
16
" thru 3
15
⁄
16
"
4
3
2
1
1
1
WARNING
1. This equipment must not be operated without proper guarding of
all moving parts. While performing maintenance be sure remote
power switches are locked off. See AMCA Publication 410 for
recommended safety practices.
2. Before starting: Check all setscrews for tightness, and rotate wheel
by hand to make sure it has not moved in transit.
*Suggested initial greasing interval: Rotate bearings during relubrica-
tion where good safety practice permits until some purging occurs at
seals. Adjust lubrication frequency depending on condition of purged
grease. Hours of operation, temperature, and surrounding conditions
will
affect
the
relubrication
frequency
required.
1. Lubricate with a multipurpose roller bearing NLGI No. 2 having rust
inhibitors and antioxidant additives, and a minimum oil viscosity of
500 SSU at 100ºF. Some greases having these properties are:
Shell - Gadus S2 V100 2 Mobil - Mobilith AW2/Mobilith SHC100
Texaco - Premium RB2
American - Rykon Premium 2
2. Lubricate bearings prior to extended shutdown or storage and
rotate shaft monthly to aid corrosion protection.
Relubrication Schedule (Months)*
Spherical Roller Bearing - Solid Pillow Blocks
Speed (RPM)
500 1000 1500 2000 2500 3000 3500 4000 4500
Shaft DIA
1
3
⁄
16
" thru 1
7
⁄
16
"
6
4
4
2
1
1
1
1
1
⁄
2
1
11
⁄
16
" thru 2
3
⁄
16
"
4
2
1
1
⁄
2
1
1
⁄
2
1
⁄
2
1
⁄
2
1
⁄
2
1
⁄
2
2
7
⁄
16
" thru 3
7
⁄
16
"
3
1
1
⁄
2
1
1
⁄
2
1
⁄
2
1
⁄
4
1
⁄
4
3
15
⁄
16
" thru 4
15
⁄
16
" 2
1
⁄
2
1
1
⁄
2
1
⁄
4
Figure 3. Solid Pillow Block Spherical Roller Bearing
Relubrication Schedule