Dodge MRC-TC06NC User manual

1
WARNING: To ensure the drive is not unexpectedly
started, turn off and lock-out or tag power source before
proceeding. Failure to observe these precautions could
result in bodily injury.
WARNING: All products over 25 kg (55 lbs) are noted on the
shipping package. Proper lifting practices are required for
these products.
Instruction Manual for Dodge®Screw Conveyor Drive
MIMA Wrapper SCXT325A Speed Reducer
These instructions must be read thoroughly before installation or operation. This instruction manual was accurate at the time of
printing. Please see dodgeindustrial.com for updated instruction manuals.
WARNING: Because of the possible danger to person(s)
or property from accidents which may result from the
improper use of products, it is important that correct
procedures be followed. Products must be used in
accordance with the engineering information specified
in the catalog. Proper installation, maintenance and
operation procedures must be observed. The instructions
in the instruction manuals must be followed. Inspections
should be made as necessary to assure safe operation
under prevailing conditions. Proper guards and other
suitable safety devices or procedures as may be
desirable or as may be specified in safety codes should
be provided, and are neither provided by Dodge nor are
the responsibility of Dodge. This unit and its associated
equipment must be installed, adjusted and maintained by
qualified personnel who are familiar with the construction
and operation of all equipment in the system and the
potential hazards involved. When risk to persons or
property may be involved, a holding device must be an
integral part of the driven equipment beyond the speed
reducer output shaft.
P
P
P
D
Figure 1 - MIMA Mounting Positions
Lubrication
SCT325A MIMA Reducer is shipped with 3-1/4 quarts of Mobil
SHC 634 ISO 460 VG. This is the recommended oil for use with
the MIMA reducer.
Guidelines for Torque-Arm Reducer
Long Term Storage
During periods of long storage, or when waiting for delivery or
installation of other equipment, special care should be taken
to protect a gear reducer to have it ready to be in the best
condition when placed in service.
By taking special precautions, problems such as seal leakage
and reducer failure due to the lack of lubrication, improper
lubrication quantity, or contamination can be avoided. The
following precautions will protect gear reducers during periods
of extended storage:
Preparation
1. Drain the oil from the unit. Add a vapor phase corrosion
inhibiting oil (VCI-105 oil by Daubert Chemical Co.) in
accordance with Table 4.
2. Seal the unit air tight.
3. Cover the shaft extension with a waxy rust preventative
compound that will keep oxygen away from the bare metal
(Non-Rust X-110 by Daubert Chemical Co.).
4. The instruction manuals and lubrication tags are paper
and must be kept dry. Either remove these documents
and store them inside or cover the unit with a durable
waterproof cover which will keep moisture away.
5. Protect the reducer from dust, moisture, and other
contaminants by storing the unit in a dry area.
6. In damp environments, the reducer should be packed
inside a moisture-proof container or an envelope of
polyethylene containing a desiccant material. If the reducer
is to be stored outdoors, cover the entire exterior with a
rust preventative.
When Placing the Reducer into Service
1. Clean the shaft extensions with petroleum solvents.
2. Fill the unit to the proper oil level using a recommended
lubricant. The VCI oil will not affect the new lubricant.
3. Follow the installation instructions provided in this manual.
Table 4 — Quantities of VCI #105 Oil
Case Size Quarts or Liters
SCXT3A .1
VCI #105 & #10 are interchangeable.
VCI #105 is more readily available.

2
REPLACEMENT PARTS
With access to an arbor press, equipment for heating and
shrinking bearings and gears on shafts, and the tools normally
found in a maintenance department, the MIMA SCXT325A speed
reducer can easily be disassembled and reassembled by careful
attention to the following instructions.
Cleanliness is very important to prevent the introduction of
dirt into the bearings and other parts of the reducer. The oil
seals are of the rubbing type and considerable care should be
exercised during disassembly or reassembly to avoid damage
to the surfaces on which the seals rub. Any sharp edges on the
input shaft or output hub should be covered with adhesive tape
or paper before performing any work on the unit. Nicks and burrs
on surfaces of the input shaft or output hub should be removed.
Ordering Parts
When ordering parts, specify MIMA SCXT325A and part number,
part name, and quantity.
Parts that must be pressed from shafts or output hub should be
removed before ordering parts. This assures that those parts, if
damaged during pressing operation, will be replaced.
It is recommended that when a pinion or gear is replaced, its
mating gear or pinion be replaced also. This ensures that the
gear teeth will mesh properly. If the large gear on the output hub
must be replaced, it is suggested that an output hub assembly,
consisting of a gear assembled on an output hub, be ordered to
secure an output hub with undamaged surfaces on which the oil
seals rub. However, if the old output hub is to be used, carefully
press the gear and bearing cones off. Thoroughly examine the
area under the oil seals for scratches or any other damage
resulting from the pressing operation. To prevent oil leakage at
the oil seals, the rubbing area must be smooth.
Replacements for the old oil seals should be ordered, due to the
probability of these parts being damaged during disassembly.
If replacing a bearing, output hub or a shaft, it is advisable to order
a set of shims for adjustment of bearings on the shaft assembly.
If replacing a housing, a set of shims should be ordered for each
shaft assembly because the adjustment of bearings on each
shaft assembly is affected.
WARNING: Equipment being removed may be too heavy to
control manually. Support it by external means. Failure to
observe these precautions could result in bodily injury.
Disconnect any electrical power to the drive. Drain lubricant
from reducer. Uncouple drive shaft and screw. Remove nuts
from trough end studs. Support drive by means of hoist and
carefully pull unit away from trough end to slide drive shaft out
of screw.
Disassembly
1. Position reducer on its side and remove bolts. Gently
tap the output hub and input shaft with a soft hammer
(rawhide, not a lead hammer) to separate the housing
halves. Open housing evenly to prevent damage to the
parts inside
2. Lift shaft, gear and bearing assemblies from housing.
3. Remove seals, seal carriers and bearing cups from
housing.
4. Clean all parts in solvent, inspect for damage and coat with
oil.
WARNING: Solvents can be toxic and/or flammable. Follow
manufacturer’s safety procedures and directions. Failure
to observe these precautions could result in bodily injury.
Reassembly:
1. Output Hub Assembly: Heat gear to 325° to 350°F for
shrinking onto output hub. Heat bearing cones to 250° to
270°F for shrinking onto output hub.
2. Countershaft Assembly: Heat gear to 325° to 350°F and
bearing cones to 250° to 270°F for shrinking onto shaft.
3. Input Shaft Assembly: Shaft and pinion are integral. Heat
bearing cones to 250° to 270°F for shrinking onto shaft.
4. Drive the dowel pins back into position in the right hand
housing half.
5. Install countershaft cover and input bearing cover in right-
hand housing half. Place housing half on blocks to allow for
protruding end of output hub. Install bearing cups in right-
hand housing half making sure they are properly seated.
6. Mesh output hub gear and small countershaft gear together
and set in place in housing. Set input shaft assembly in
place in the housing. Make sure bearing rollers (cones) are
properly seated in their cups. Set bearing cups for left-
handed housing half in place on their rollers.
7. Clean housing ange surfaces on both halves, making
sure not to nick or scratch ange face. Place a new bead
of gasket eliminator on ange face and spread evenly over
entire ange leaving no bare spots. Place other housing half
into position and tap with a soft hammer (rawhide, not lead
hammer) until housing bolts can be used to draw housing
halves together. Torque housing bolts to 720 lb-ins.
CAUTION: If too much sealant is used, it will run into
the bearing, and too little sealant will result in an
ineffective seal.
8. Apply RTV to all seal O.D.s. Extreme care should be used
in installing seals on input shaft and output hub to avoid
damage to seals due to contact with sharp edges of the
keyseat in the input shaft or the retaining ring groove in
the output hub. This danger of damage and consequent
oil leakage can be decreased by covering the keyseat
and groove with tape or paper which can be removed
subsequently. Chamfer or burr housing bore if end of
bore is sharp or rough. Fill cavity between lips of seal
with grease. Seats should be pressed or tapped with a
soft hammer evenly into place in the housing, applying
force only on outer corner of seals. A slight oil leakage at
the seals may be evident during initial running in, but will
disappear unless the seals have been damaged.
Place output hub seal carrier in position, shim and torque
bolts per special procedures.
9. Fill with approximately 3¼ quarts of Mobil SHC 634 oil, ISO
460 VG.

3
MODIFIED ASSEMBLY PROCEDURE
SCXT325A MIMA/ITW (WRAPPER UNITS)
1. 1. All assembly procedures for standard SCXT325A should
be followed except for the following changes in shimming
of output bearing.
2. 2. New output bearing shimming procedures:
a. Place output bearing cup in left half of housing. Ensure
the bearing cup is correctly seated.
b. Position output hub seal carrier (without shims) and
install two carrier screws diametrically opposed.
c. Torque each screw to 50 lb.-in. Rotate the output hub
to roll in the bearings, then torque each screw to
100 lb.-in. Rotate the output hub again to roll in the
bearings.
d. Seat output bearings by tapping the seal carrier with
a hammer; turning the output hub through 360 degrees
to further roll in the bearings. Torque carrier bolts
again to 100 lb.-in. Repeat this process of hammering,
turning the output hub, and torquing to 100 lb.-in. until
bearings are completely seated (3-4 seatings may be
required).
e. With a feeler or taper gauge, measure the gap between
the housing and the carrier, clockwise from and next to
each screw.
f. To determine the required shim pack thickness,
subtract .005 in. from the average of the two gauge
readings (Pack Thickness = Gauge Average – .005 in.).
g. Remove the output hub seal carrier and install the
required shims (shim pack thickness should be
inspected with a 0-1” micrometer).
Note: Total shim thickness per carrier should not
include more than .009” plastic shims. All other
shims should be metal, and each plastic shim
should be inserted between two metal shims.
h. Continue with normal assembly procedure from this
point. (Carrier bolt torque should be 204 lb.-in.)
3. Place countershaft bearing carrier in position without
shims and install two carrier screws diametrically opposed.
Torque each screw to 25 lb.-ins. Rotate the output hub to
roll in the bearings and then torque each screw once to 50
lb.-ins. Do not retorque screws. Again turn countershaft to
roll in the bearings. With a feeler or taper gauge, measure
the gap between the housing and the carrier, clockwise
from and next to each screw. To determine the required
shim thickness, take the average of the two feeler gauge
readings. Remove carrier and install the required shims.
Note: Total shim thickness per carrier should not include
more than .009” plastic shims, and each plastic shim
should be inserted between two metal shims. Place a
diameter bead of Dow Corning RTV732 sealant on the face
around the I.D. of the end shim (sealant is to be between
reducer housing and shim) and install carrier on reducer
housing. Torque carrier bolts to 204 lb-ins. Countershaft
should have an axial end play of .001” to .003”.
4. Using the same procedure as in step 3 adjust the input shaft
bearings, except the axial end play should be .002” to .003”.
Torque bearing carrier to 204 lb-ins.
Table 5 — Manufacturers’ Part Numbers For Replacement
Output Shaft Bearings
TORQUE-ARM Reducer
Drive Size
Output Hub Bearing
DODGE
Part Number
Manufacturer’s Part
Number
SCXT3A 402272 LM814849
403127 LM814810
Table 6 — Manufacturers’ Part Numbers For Replacement
Countershaft Bearings
TORQUE-ARM Countershaft Bearing Input
Side
Countershaft Bearing Adapter
Side
Size Dodge
Part No.
Manufacturer’s
Part Number
Dodge
Part No.
Manufacturer’s
Part Number
SCXT3A 402273 15102 402273 15012
403094 15245 403094 15245
Table 7 - Manufactures’ Part Numbers For Replacement Input Shaft Bearings
TORQUE-ARM Input Bearing
Input Side
Input Bearing
Adapter Side
Size Dodge
Part No.
Manufacturer’s
Part Number
Dodge
Part No.
Manufacturer’s
Part Number
SCXT3A 402204 LM48548A 402273 15102
403139 LM48510 403094 15245

Parts For SCXT325 MIMA Reducer
44,45
46,47
34
52
48
26
21
56,57
78
50
80,81
77
62
16,19
22,24
82
32,33
80,81
60
64
78
76
32,33
58
54,55
59
42
41
40
32,33
28
30
Parts For SCXT325 MIMA Reducer
Reference Name of Part Number
Required SCXT3A
16
19
HOUSING
Housing Bolt
Washer
1
8
16
961405
411463
419057
22
24
①
①
21
26
Hex Nut
Dowel Pin
Pipe Plug
Magnetic Plug
Countershaft Cover Screws
(Backstop Side)
Countershaft Bearing Cover
(Backstop Side)
8
2
5
1
4
1
407268
420055
430031
430060
416519
243559
28
30 ②
Input Shaft Seal Carrier
Input Shaft Bearing Shim Pack
.002" Thick
.005" Thick
.010" Thick
.025" Thick
1
2③
④
④
④
④
243543
389704
427841
427842
427843
427844
32
33
34
Carrier and Cover Screws
Lockwasher
Backstop Cover
14
14
1
411390
419010
361062
40 ②Input Shaft
with Pinion 25:1 Ratio 1961404
41 Input Shaft Key 1 443032
44 ②
45 ②
46 ②
47 ②
Input Shaft Bearing
(Input Side)
Input Shaft Bearing
(Backstop Side)
Cone
Cup
Cone
Cup
1
1
1
1
402204
403139
402273
403094
COUNTERSHAFT
ASSEMBLY ⑤
25:1 Ratio 1389701
48 ⑥ Countershaft with Pinion 1243555
50 ② ⑥ First Reduction Gear 25:1 Ratio 1243239
52 ②⑥ Key 1243215
54 ②
55
56 ②
57 ②
Countershaft Bearing
(Input Side)
Countershaft Bearing
(Backstop Side)
Cone
Cup
Cone
Cup
1
1
1
1
402273
403094
402273
403094
58 Countershaft Bearing Cover
(Input Side)
1243545
59 ②Countershaft Bearing Shim Pack
.002" Thick
.005" Thick
.010" Thick
.025" Thick
2 ③
④
④
④
④
389705
427845
427846
427847
427848
60 ②
62 ②
64 ②
OUTPUT HUB ASSEMBLY ⑤
⑥ Output Hub
⑥ Output Gear
⑥ Output Gear Key
1
1
1
2
389702
961297
243570
243216
76
77
Output Hub Seal Carrier
(Input Side)
Roll Pin
1
1
C15073
409022
80 ②
81 ②
Output Hub
Bearing
Cone
Cup
2
2
402272
403127
82 ②Output Hub Bearing Shim Pack
.002" Thick
.005" Thick
.010" Thick
.025" Thick
2 ③
④
④
④
④
389706
427849
427850
427851
427852
42 ②
78 ②
SEAL KIT ⑤ ②
⑥ Input Shaft Seal
⑥ Output Shaft Seal
1
1
2
389720
243558
243578
Parts For SCXT325 MIMA Reducer
Reference Name of Part Number
Required SCXT3A
①
①
RTV Sealant, Tube
⑥ Key (Output)
1
1
465044
443089
①Not shown on drawing
②Recommended spare parts
③One set consists of one each of the shims listed immediately below marked
④If replacing a bearing, output hub or a shaft, it is advisable to order a set of shims for
adjustment of bearings on the shaft assembly. If replacing a housing, a set of shims
should be ordered for each shaft assembly because the adjustment of bearings on
each shaft assembly is affected.
⑤Includes parts listed immediately below.
⑥Parts marked make up the assemblies under which they are listed
Dodge Industrial, Inc.
1061 Holland Road
Simpsonville, SC 29681
[phone]
All Rights Reserved. Printed in USA.
MN1669 02/22
*1669-0222*
© DODGE INDUSTRIAL, INC.
AN RBC BEARINGS COMPANY