CAMCORP Blower Package with Roots Blower - Manual (Page 34)

11 ©2002 Dresser, Inc. all rights reserved.
ROOTS, RAM, URAI and WHISPAIR are trademarks of Dresser, Inc.
Dresser Design and Universal RAI are registered trademarks of Dresser, Inc.
It is recommended that major repairs be performed
at an authorized ROOTS facility. However, it is
recognized that this may not always be practical. If a
blower is out of warranty, mechanical adjustments and
parts replacement may be undertaken locally at the
owner’s option and risk. It is recommended that
ROOTS
™ parts be used to insure fit and suitability. The
maintenance of a small stock of on-hand spare parts
can eliminate possible delays. When ordering parts
give item numbers and their word descriptions from the
appropriate sectional drawings. Also specify quantities
required and the blower model and serial number from
the nameplate.
Repairs or adjustments are best performed by person-
nel with good mechanical experience and the ability to
follow the instructions in this manual. Some operations
involve extra care, patience, and a degree of precision
work. This is especially true in timing impellers and in
handling bearings. Experience indicates that high
percentages of bearing failures are caused by dirt
contamination before or during assembly. Therefore,
the work area should be cleaned before starting
disassembly, and new or re-usable parts protected
during progress of the work.
In the following repair procedures, numbers shown in
brackets ( ) correspond to the item numbers used
in sectional drawings. It is recommended that the
procedures be studied carefully and completely, with
frequent reference to the drawings, before starting
work. This will produce better efficiency through an
understanding of what work is to be done, and the
order of doing it. Before disassembly, mark all parts
so that they may be returned to original locations or
relative positions.
Requirements for special tools will depend on the work
to be done. If impeller clearances and float are to be
checked or re-set, a dial indicator and a set of long
feeler gauges will be needed. Work involving removal
of the timing gears cannot be accomplished without a
suitable puller.
Design of ROOTS ™ blower is simple, and most repair
operations are straightforward. For this reason, the
following procedures are intended mainly to indicate
a preferred work order and to call out points to be
observed. Where special operations are required,
detailed coverage is given.
A – Replacing Timing Gears
1. Drain all oil from the gearhouse by removing drain
plug (21) in the bottom. Remove gearhouse by
taking out all cap screws (23) in its flange. It may
be necessary to bump the sides with a wood block
or mallet to break the flange joint.
2. Reach through one of the blower pipe connections
and place a chalk mark on the strip of one impeller
and the mating waist of the other, so that they
may easily be returned to their original relative
positions.
3. GEAR REMOVAL: CAUTION: Do not remove gear
nuts (17) completely before the gears are unseated
from the taper fits or damage/injury may result.
For this operation, the impellers should be wedged,
as shown in Table 5. Back off gear clamping nuts
(17) about 1/4”. Use a suitable puller or wedge. As
the puller set screw is torqued, the puller will have
a tendency to turn and contact teeth of the other
gear. To prevent this contact, hold the puller corner
nut with a wrench while torquing the set screw.
Once the gear is unseated, remove the puller.
Remove gear nuts (17) and the gear.
4. GEAR INSTALLATION: Place impellers in correct
position as previously marked. Be sure shafts and
gear bores are clean, oil free and free of scratches.
Clean the shaft tapered fits. Place hardwood
wedges as shown in Table 5. Install drive gear
(4) and gear nut (17). Tighten the drive gear nut
to the torque given below. Blower assembly
must be fastened down for torquing operation.
5. Installing driven gear (4) – Insert a long, metal
feeler gauge between the impellers’ lobes at the
fronts or backs as shown below. Feeler
gauge thickness to be a middle value from Table 5
for fronts and backs. Install nut (17). Tighten lightly
with a small wrench, then check front and back
clearances against Table 5 for each 45° position.
Both fronts and backs should be about the same
and within the specified range in Table 5. Adjust
gear position, if necessary, then insert the
corrected feeler gauge and wedges and use a
torque wrench to tighten the gear nut to the torque
specified in below. Remove wedges and rotate
the drive shaft by hand to make sure there are no
gear tight spots or impeller contacts. CAUTION!
Keep fingers away from impellers and gears.
U
NIVERAL
RAI ®
SERIES BLOWER G EAR N UT T ORQUE
Frame Size Torque
lb.-ft. (kg-m)
22, 24, 60 (8.3)
32, 33, 36 110 (15.2)
42, 45, 47 190 (26.3)
53, 56, 59 250 (34.6)
65, 68, 615 400 (55.3)
76, 711, 718 550 (76.1)