Rexnord Falk NRT E 70 User manual

Falk®Horizontal Shaft Backstops •Oil Seal Replacement
Type NRT • Sizes 70-180, 1070-1185, Model E (Page 1 of 3)
Rexnord, 3001 W. Canal St., Milwaukee, WI 53208-4200, USA 568-131
Telephone: [phone] Fax: [phone] October 2014
www.rexnord.com NEW
How to Use this Manual
This manual applies to standard Falk Type NRT backstops.
This manual provides detailed instructions on oil seal
replacement. Use the following Table of Contents to locate
required information.
Table of Contents
Oil Seal Replacement...................................................... 1-2
Backstop Removal...............................................................1
Seal Replacement ...............................................................2
Backstop Installation ....................................................... 2-3
CAREFULLY FOLLOW THE INSTRUCTIONS IN THIS
MANUAL FOR OPTIMUM PERFORMANCE AND
TROUBLE FREE SERVICE.
Introduction
This manual covers oil seal replacement for both new model
cast iron and fabricated steel end covers. See Page 2.
CAUTION: Remove all external loads from drive before
servicing drive or accessories. Do not damage inner cam hub
face: new seals will leak if seal contacting surface is marred. Do
not use abrasive material on seal contacting surface.
Required Equipment
In addition to standard mechanic’s tools, the following
equipment is required: hoist, sling, torque wrench, dial
indicator with stand or depth micrometer and puller.
CAUTION: Do not attempt to service or remove backstop
before removing load. When removing backstop from shaft,
do not apply heat to the backstop. Apply axial force to the
inner cam hub face of the backstop only.
Backstop Removal
1. Drain and discard lubricant in an environmentally safe
method.
2. Remove oil sight gauge and breather assembly and
insert pipe plugs in cover holes.
3. Remove torque arm. Refer to Figure 1 for proper
method of supporting and lifting.
4. Reassemble torque arm pins in backstop and lock in
place with cotter pins for lifting.
5. If the backstop is furnished with an axial retaining collar(s),
loosen set screws and mounting bolts and remove collar.
Remove burrs on shaft caused by set screws.
6. Remove backstop from shaft. Apply force to the inner
cam hub face of the backstop only. (Figure 1)
7. Thoroughly clean exterior of backstop with clean
solvent to prevent dirt from falling into the backstop
when disassembling.
8. Position backstop on clean work surface with bore
vertical.
COTTER PIN
TORQUE ARM PIN
END COVER
INNER CAM HUB FACE-
PUSH ON THIS FACE
WHEN INSTALLING
BACKSTOP ON SHAFT
BALANCE
POINT
NYLON
SLING
TORQUE ARM
CLAMPS TO PREVENT
SLING FROM SLIPPING
OFF "I" BEAM
NYLON SLING
Figure 1

Oil Seal Replacement •Falk Horizontal Shaft Backstops
(Page 2 of 3) Type NRT • Sizes 70-180, 1070-1185, Model E
568-131 Rexnord, 3001 W. Canal St., Milwaukee, WI 53208-4200, USA
October 2014 Telephone: [phone] Fax: [phone]
NEW www.rexnord.com
BACKSTOP SEAL REPLACEMENT
Removal
CAUTION: Remove all external loads from drive before
servicing drive or accessories. Do not damage cam hub
face: new seals will leak if seal contacting surface is
marred. Do not use abrasive material on seal contacting
surface.
1. To prevent dirt from falling into the backstop,
thoroughly clean the exterior of backstop with clean
non-flammable solvent.
2. Remove labyrinth cover (See Figure 4) from backstop.
Clean cam and hub face with solvent and remove all
sharp edges.
3. Outer Seal —With a hook shaped tool reach over
the outer seal and pull outward moving around the
opening, (see Figure 2).
4. Inner Seal — Use a sharp center punch to lightly
punch the seal case as a guide for the drill.
5. Wrap several turns of tape around the drill
approximately .250” (6mm) from the drill point to
prevent the drill from entering too deeply into the
housing and damaging the bearing (inner seal only).
Grease or magnetize the drill to help retain the chips.
Drill two .125” (3mm) diameter holes in the seal case
180° apart. Control the angle of the drill as illustrated
in Figure 6 to prevent damage to the cam.
6. Insert two #10 sheet metal screws of sufficient length
into the seal. DO NOT drive the screw more than .250”
(6mm) beyond seal face or bearing damage may
occur. Use a claw type pry bar under the screw head
as shown in Figure 6, and pry the seal out. Remove
all chips. Use a magnet to remove the chips that fall
into the bore. Remove Permatex sealant from housing
bore. Inspect the seal cavity and remove any debris
or metal chips. Thoroughly clean the seal cavity with
clean non-flammable solvent.
Installation
1. Check seal surface for any damage prior to installing
new seals. Install one seal at a time. Coat the outside
diameter of the inner seal housing bore with Permatex
#3 or equivalent sealant.
5. Outer Seal — Apply a thin layer of NLGI#2 grease to
the outward face of the inner seal. Position the new
outer seal on the inner cam with the lip facing inward
(See Figure 4). Stretch the seal around the inner cam
moving around the diameter evenly until the outer seal
is installed to the depth as found in Table 1.
6. Check seal runout with a depth micrometer, dial
indicator or bar micrometer as shown in Figure 3.
Runout must not exceed .010” (0.25mm) TIR.
7. Replace the labyrinth cover and screws. Ensure the
gap between the inner cam and labyrinth cover is
even all the way around. (See Figure 7.) Torque the
bolts to 14-17 lb-ft (18-23 Nm).
INNER SEAL RUNOUT
REFERENCE SURFACES
MEASURE PROPER
DEPTH USING DESIRED
MEASURING METHOD AS NOTED
Figure 3
Figure 4
OUTER SEAL
INSTALLATION DEPTH
LABYRINTH
COVER
2. Inner Seal — Position the inner seal squarely in the end
cover with the garter spring positioned per Figure 7.
3. Place a square ended cylindrical tool against the seal
and press or lightly tap the tool (not the seal) until the
seal is seated against the shoulder. (Figure 3)
4. Check inner seal backface runout with a depth
micrometer, dial indicator, or bar micrometer as
shown in Figure 3, must be performed prior to outer
seal installation. Runout must not exceed
.010” (0.25mm) TIR.
Figure 2

Falk Horizontal Shaft Backstops •Oil Seal Replacement
Type NRT • Sizes70-180, 1070-1185, Model E (Page 3 of 3)
Rexnord, 3001 W. Canal St., Milwaukee, WI 53208-4200, USA 568-131
Telephone: [phone] Fax: [phone] October 2014
www.rexnord.com NEW
Backstop Installation
Refer to Manual 568-111 for backstop installation, oil sight
gauge assembly, and lubrication recommendations.
CAUTION: An important part of the Falk NRT backstop
manufacturing process is the full load and overrunning
testing with specially instrumented equipment.
Consequently, return NRT backstops to Rexnord for repair
and full load testing.
Except for replacement of shaft seals, NRT backstops
should not be dismantled or repaired in the field. If seals
are to be replaced, it is important that the cam and roller
assemblies not be removed from the outer race. Removal
will void applicable warranties.
When contacting Rexnord concerning required service,
state the nature of problem and give complete data from
backstop nameplate; order number, size, date, etc.
LABYRINTH
COVER
INNER SEAL
SHOULDER
GARTER
SPRINGS
ENSURE EVEN
GAP WHEN
INSTALLING
COVER
TABLE 1 — Outer Seal Installation Depth
NRT Size Outer Seal
Inch mm
1075 0.614 ±0.009 15.60 ±0.23
1085 0.672 ±0.020 17.07 ±0.51
1095 0.768 ±0.020 19.51 ±0.51
1105 0.511 ±0.107 12.98 ±2.72
1115 0.669 ±0.051 16.99 ±1.30
1125 0.629 ±0.044 15.98 ± 1.10
1135 0.444 ±0.022 11.28 ±0.55
1145 0.571 ±0.044 14.50 ± 1.10
1155 0484 ±0.044 12.29 ±1.10
1165 0.784 ±0.044 19.91 ±1.10
1175 0.884 ±0.044 22.45 ±1.10
1185 0.914 ±0.044 23.22 ±1.10
Figure 5 Figure 6
Figure 7