Rexnord Thomas Tpack 52 Series Installation And Maintenance

ATEX: In order for this coupling to meet
the ATEX requirements, it is mandatory to
precisely follow these installation instructions
along with the included supplement form
0005-08-49-01. This supplement outlines the
ATEX requirements. If the operator does not
adhere to these instructions, conformity is immediately
invalidated.
WARNING: Because of the possible danger to person(s)
or property from accidents which may result from improper
use or installations of products, it is extremely important to
follow the proper selection, installation, maintenance and
operational procedures.
All rotating power transmission products are potentially
dangerous and can cause serious injury. They must be
properly guarded in compliance with OSHA, ANSI, and
any other local standards for the speeds and applications
in which they are used. It is the responsibility of the user to
provide proper guarding.
For ATEX requirements the guard must have a minimum of
½ inch (12.7 mm) radial clearance to the coupling major
diameter "A" (See Figure 1) and allow for good ventilation.
1. Purpose — These instructions are intended to help you
to install, align, and maintain your THOMAS coupling.
2. Scope — Covered here will be general information, hub
mounting, alignment, assembly, locknut torque, disc
pack replacement, and part numbers.
3. General Information — The coupling, as received,
may or may not be assembled. If assembled, the
locknuts are not fully tightened. Examine the parts to
assure there is no visible damage. If the coupling is
assembled, remove the bolts, locknuts, and washers
that attach the hubs to the disc packs. Remove both
hubs. Leave the disc packs attached to the center
member assembly.
LOCKNUT
SINGLE HEADED BUSHING
WASHER
HUB
A
Figure 1
Rexnord Industries, LLC, 5555 S. Moorland Rd., New Berlin, WI 53151-7953
Telephone: 262-796-4060 Fax: 262-796-4064
e-mail: info@rexnord.com web: www.rexnord.com
Rexnord Thomas
®
Series 52 • Sizes 225-750 (Tpack)
N N
C
Disc Couplings • Installation and Maintenance
®
4. Hub Mounting
A. General. Clean the hub bores and shafts. Remove
any nicks or burrs. If the bore is tapered, check
for a good contact pattern. If the bore is straight,
measure the bore and shaft diameters to assure
proper fit. The key(s) should have a snug side-to-
side fit with a small clearance over the top, and the
corners must be chamfered.
B. Straight Bore — Install the key(s) in the shaft. If the
hub is an interference fit, heat the hub in oil bath
or oven until the bore is sufficiently larger than the
shaft. 350ºF is usually sufficient. An open flame is
not recommended. However, if flame heating is
necessary, use a very large rose bud tip to give
even heat distribution. A thermal heat stick will help
determine hub temperature. DO NOT SPOT HEAT
THE HUB OR DISTORTION MAY OCCUR. With the
hub expanded, slide it quickly up the shaft to the
desired axial position. A pre-set axial stop device
can be helpful.
C. Straight Bore Slip Fit — Install the key(s) in the
shaft. Install the set screw(s) in the hub making sure
they do not protrude into the keyway or the bore.
Now slide the hub up the shaft to the desired axial
position. The set screw(s) which hold the hub in
place are tightened, using a torque wrench, to the
values shown in Table 1A.
NOTE: Never use two set screws one on top of the
other.
D. Taper Bore — Put the hub on the shaft without the
key(s) in place. Lightly tap the hub on the shaft with
a soft hammer. This will assure a metal-to-metal fit
between shaft and hub. This is the starting point
for the axial draw. Record the position between
shaft end and hub face with a depth micrometer.
Mount a dial indicator to read axial hub movement.
CENTER MEMBER
TPACK  DISC PACK
BOLT
HUB
(Page 1 of 4)
BOLT HOLE
CLEARANCE HOLE
538-212
November 2008
Supersedes CP-Series 52-T, 8-06