Eaton Airflex WCB2 Series User manual

WCB11070
WCB2 Tensioner/Brake Installation, Operation and Maintenance Manual
Airex®Product Line 204182

EATON WCB11070 WCB2 Tensioner/Brake Installation, Operation and Maintenance Manual E-CLCL-II016-E December 20162
WCB2 Tensioner/Brake
General Information
Warning
Forward this manual to the person responsible for Installation,
Operation and Maintenance of the product described herein.
Without access to this information, faulty Installation,
Operation or Maintenance may result in personal injury or
equipment damage.
Caution
Use Only Genuine Airex®Replacement Parts
Eaton's Airex division recommends the use of genuine
Airex replacement parts. The use of non-genuine
Airex replacement parts could result in substandard
product performance, and may void your Eaton warranty.
For optimum performance, contact Airex:
In the U.S.A. and Canada: [phone]
Outside the U.S.A. and Canada: [phone]
Internet: www.eaton.com/airex
!!

EATON WCB11070 WCB2 Tensioner/Brake Installation, Operation and Maintenance Manual E-CLCL-II016-E December 2016 3
Table of Contents
Section Description Page No.
CUTAWAY DRAWINGS 5 & 6
1.0 INTRODUCTION 7
1.1 Description 7
1.2 How It Works 7
2.0 INSTALLATION 8
2.1 Preparation and Arrangements 8
2.2 Mounting 9
2.3 Air System 10
2.4 Coolant System 10
3.0 OPERATION 14
3.1 Conditions of Operation 14
3.2 Pressure and Speed Limits 14
3.3 Periodic Maintenance 14
4.0 MAINTENANCE 16
4.1 Wear Limits 16
4.2 Wear Adjustment 16
4.3 Disassembly Procedures 19
4.4 Friction Material Replacment (8WCB2 and 14WCB2) 19
4.5 Friction Material Replacment (18WCB2, thru 48WCB2) 20
4.6 Wear Plate Replacement 21
4.7 Cylinder Seal Replacement 23
4.8 Bushing Replacement 25
4.9 Assembly Procedures 25
4.10 Corrosion Protection 26
5.0 ORDERING INFORMATION/TECHNICAL ASSISTANCE 27
5.1 Equipment Reference 27
6.0 PARTS 28
6.1 Parts (Standard) 28
6.2 Parts (Corrosion Resistant) 31
7.0 KITS 38
7.1 Friction Disc Kits (Standard) 38
7.2 Friction Disc Kits (Corrosion Resistant) 39
7.3 Cylinder Seal Kits 39
7.4 Wear Plate Kits for Mounting Flange and Pressure Plate 40
7.5 Wear Plate Kits for Reaction Plate 40
8.0 REVISION PAGE 41

EATON WCB11070 WCB2 Tensioner/Brake Installation, Operation and Maintenance Manual E-CLCL-II016-E December 20164
Index of Tables
Table No. Table Title Page No.
1 Item Description 5
2 Alignment Requirements 8
3 "A" dimension on Figure 1 & 2 inches (mm) 8
4 Fastener Description and Assembly Torque - ft.-lb. (Nm) 9
5 Air Inlet Size 10
6 Coolant Pressure, psi (bar) 11
7 Coolant Supply Data 11
8 Maximum Outlet Coolant Temperature 13
9 Maximum Friction Disc Assembly Speeds 14
10 Wear Measurements X, Y & Z Gaps – Inches (mm) 18
11 Wear Plate Fastener Torque: ft.lb. (Nm) 22
12 Inlet and Outlet Water Port Sizes 23
13 Wear Limits for WCB2 Components inches (mm) 27

EATON WCB11070 WCB2 Tensioner/Brake Installation, Operation and Maintenance Manual E-CLCL-II016-E December 2016 5
WCB2 Tensioner/Brake
Figure 1
Table 1
Item Description
Item Description
1 Mounting Flange S/A
6 Stud
7 Friction Disc S/A
12 Clamp Tube
13 Pressure Plate S/A
17 Flat Washer
Item Description
18 Self Locking Nut
19 Cylinder
21 Seal (Inner)
23 Seal (Outer)
28 Gear (Not Included in P/L)
29 Wear Spacer
Item Description
30 Reaction Plate S/A
33 Piston
34 Release Spring
105 Pipe Plug
19
16
7
12
13 17
18
28
29 30
34
'A'
21
33
23
57

EATON WCB11070 WCB2 Tensioner/Brake Installation, Operation and Maintenance Manual E-CLCL-II016-E December 20166
WCB2 Tensioner/Brake
Figure 2
21
23
29
1 7 13
17
18
19
30
33
34
28
6
12
105
'A'

EATON WCB11070 WCB2 Tensioner/Brake Installation, Operation and Maintenance Manual E-CLCL-II016-E December 2016 7
WCB2 Tensioner/Brake
1.0 INTRODUCTION
Throughout this manual there are a number of
HAZARD Warnings that must be read and adhered
to in order to prevent possible personal injury and/or
damage to equipment. Three signal words “Danger”,
"Warning", and "Caution" are used to indicate the
severity of a hazard, and are preceded by the safety
alert symbol
Danger
Denotes the most serious hazard, and is used when
serious injury or death WILL result from misuse or
failure to follow specic instructions.
Warning
Used when serious injury or death MAY result from
misuse or failure to follow specic instructions.
Caution
Used when injury or product/ equipment
damage may result from misuse or failure to
follow specic instructions.
It is the responsibility and duty of all personnel
involved in the installation, operation and
maintenance of the equipment on which this device
is used to fully understand the:
Danger Warning Caution
procedures by which hazards can be avoided.
1.1 Description
1.1.1 The Airex®WCB2 water-cooled tensioner/
brake assembly is designed for constant tension
applications. It is exceptionally well suited for high
inertia stopping and rapid heat dissipation. The
design of the WCB2 tensioner/brake assembly
permits mid-shaft or end-shaft mounting. The rugged
construction ensures long, trouble free service.
1.1.2 WCB2 tensioner/brake assemblies are available
in various sizes and quantities of friction disc
assemblies. The model number identies the number
of discs and the nominal friction disc assemblies
diameter. For example, 324WCB2 indicates three
24" diameter discs.
1.1.3 When size, such as 36WCB2, is referred to in this
manual, it means that the information given applies
to all models using the 36" diameter watercooled disc
assembly; i.e., 236WCB2, 336WCB2, etc.
1.1.4 WCB2 tensioner/brake assemblies can be used with
either closed loop or open loop water systems.
1.1.5 This manual includes metric equivalents usually
shown in brackets (#) following the U.S.
measurement system value. Be sure to use the
correct value.
1.2 How It Works
1.2.1 Referring to Figure 1, the gear (28) is mounted on
the shaft which is to be stopped and the WCB2
tensioner/brake assembly is attached to the machine
frame or a reaction bracket.
Air pressure is applied through the ports in the
cylinder (19) causing the piston (33) and pressure
plate assembly (13) to move towards the mounting
ange, compressing the release springs. As the
applied pressure increases, the friction disc(s) are
clamped between the pressure plate and mounting
ange, stopping or controlling the shaft the discs
are mounted on. Modulation of air pressure then
controls applied torque of the WCB2 tensioner/
brake assembly. Multiple disc assemblies utilize
reaction plates (30) between friction disc assemblies.
The release springs (34) assist in disengagement
and retraction of the piston, pressure plate, and
reaction plates, if applicable. High heat dissipation
is accomplished by passing water through a special
cavity behind the copper alloy wear plates.
Torque ows through the WCB2 tensioner/brake
assembly from the shaft to be controlled, through the
friction disc assemblies, through the pressure plate
and reaction plates, through the clamp tubes and
studs, to the mounting ange, which is attached to a
rigid surface.

! ! !

EATON WCB11070 WCB2 Tensioner/Brake Installation, Operation and Maintenance Manual E-CLCL-II016-E December 20168
WCB2 Tensioner/Brake
2.0 INSTALLATION
Warning
Only qualied maintenance personnel should install,
adjust or repair these units. Faulty workmanship
will result in unreasonable exposure to hazardous
conditions or personal injury.
Caution
Read these instructions thoroughly and review until
you fully understand the installation sequence before
proceeding with the work described in this section.
Failure to follow these instructions will result in
unreasonable exposure to hazardous conditions or
personal injury.
Caution
Do not paint the clamp tubes (12), wear spacers
(29), or the release springs (34), as this may hinder
the engagement or disengagement of the WCB2
tensioner/brake assembly.
Note: Some three and four disc units may require support on
the cylinder end of the WCB2 tensioner/brake assembly in
certain high torque applications. Contact the factory for specic
application information.
2.1 Preparation and Arrangements
2.1.1 Refer to the appropriate catalog information
(available upon request) for appropriate envelope
dimensions, mounting register diameters, mounting
bolt circles and positions, and stud support bracket
recommendations for each specic WCB2 tensioner/
brake assembly.
2.1.2 The WCB2 tensioner/brake assembly's reaction
member (such as the machine frame) should have
a machined register to allow for mounting and
alignment control of the WCB2 tensioner/brake
assembly. The mounting surface should be designed
to provide full support of the face of the mounting
ange (1), preventing deection during operation.
2.1.3 For proper operation and service life, the WCB2
tensioner/brake assembly's reaction member
must be aligned to the shaft within the limits
shown in Table 2.
Caution
Proper alignment is necessary to ensure that the
friction disc assemblies track properly. Improper
alignment will result in excessive wear to the friction
material and mating surfaces, plus the gear and
splined bore of the friction disc assemblies.
See Figure 3.
CORRECT INCORRECT
Figure 3
Table 2
Alignment Requirements
Concentricity
(Parallel, TIR) of Perpendicularly
Shaft and (Angular,TIR) of
tensioner/brake Mounting Flange to
Size assembly Inches (mm) Shaft* Inches (mm)
8WCB2 0.005 (0,13) 0.005 (0,13)
14WCB2 0.010 (0,25) 0.007 (0,18)
18WCB2 0.010 (0,25) 0.010 (0,25)
24WCB2 0.010 (0,25) 0.012 (0,30)
36WCB2 0.010 (0,25) 0.019 (0,48)
48WCB2 0.010 (0,25) 0.025 (0,64)
*Perpendicularity measured near the outside diameter of the mounting ange.
Table 3
"A" dimension on Figure 1 & 2 inches (mm)
Size 1xxWCB2 2xxWCB2 2xxWCB2 4xxWCB2
8WCB2 1.00 (25,4) 1.38 (35,0) 0.19 (4,8) N/A
14WCB2 1.06 (26,9) 1.69 (42,9) 1.06 (26,9) N/A
18WCB2 1.25 (31,8) 1.25 (31,8) 1.25 (31,8) 1.25 (31,8)
24WCB2 1.38 (35,1) 1.38 (35,1) 1.38 (35,1) 1.38 (35,1)
36WCB2 2.36 (59,9) 2.36 (59,9) 2.36 (59,9) 2.36 (59,9)
48WCB2 1.96 (50,0) 1.75 (44,0) 1.75 (44,0) 1.75 (44,0)
2.1.4 Refer to Table 3 for the setup dimension between
the WCB2 tensioner/brake assembly's mounting
surface and the end of the gear (dimension "A" on
Figure 1). Gears should be positioned to ensure
that when the WCB2 tensioner/brake assembly is
mounted the disc splines will not overhang the end
of the gear when components are in both new and
worn conditions. The gear is typically bored and
keyed for a resulting Class FN2S interference t
for inch shafting and ISO System S7h6 for metric
shafting. Contact Airex Application Engineering for
specic recommendations.

EATON WCB11070 WCB2 Tensioner/Brake Installation, Operation and Maintenance Manual E-CLCL-II016-E December 2016 9
2.2 Mounting
2.2.1 The WCB2 must be mounted to a clean, rigid surface
with hardened at washers and screws of the grade,
quantity, and size as listed in Table 4. Mounting to a
properly aligned, rigid surface that fully supports the
face of the mounting ange minimizes any deection
during operation and helps to ensure that the friction
disc assemblies will track properly on the copper
wear plates.
Note: To facilitate the mounting process, the friction disc
assemblies should be aligned to the gear and centered in the
WCB2 tensioner/brake assembly. With the WCB2 tensioner/
brake assembly positioned with the mounting ange facing
down, lower the gear (28) slowly and carefully into the splined
bore of the friction disc assemblies (7). Adjust the friction disc
assemblies so that they are centered in the WCB2 tensioner/
brake assembly and t in the gear. Apply and maintain an air
pressure of 25 psig (1.7 bar) to the cylinder. This will engage and
hold the friction disc assemblies in position during installation.
Remove the gear.
Danger
Use only the proper number and grade fasteners
shown in Table 4. Use of commercial grade (Grade
2) fasteners where Grade 8 fasteners are specied
may result in failure of the fasteners and a sudden
and drastic reduction in brake torque.
Caution
Water inlets and outlets must be located as close as
possible to the 6 o'clock and 12 o'clock positions,
respectively. This will help to prevent air pockets
in the water cavities, which would allow the WCB2
tensioner/brake assembly to overheat.
2.2.2 Ensure that the shaft is free of nicks or burrs and the
key ts properly in the shaft and gear.
2.2.3 Apply a light coat of anti-seizing compound to the
shaft and key. Tap the key into the shaft keyway.
Table 4
Fastener Description and AssemblyTorque - ft.-lb. (Nm)
Item Description Specication 8WCB2 14WCB2 18WCB2 24WCB2 36WCB2 48WCB2
4 Wear Plate Size #10-24NC 1/4-NC2 5/16-18 NC Gr. 8 5/16-18NC Gr. 8 3/8-16NC2Gr. 8 3/8-16NC2Gr. 8
Screw Quantity 42 60 80 90 108 120
5 Locknut Torque, Dry 5 (7) 12 (16) 21 (28) 21 (28) 40 (54) 40 (54)
18 Locknut Size 1/2-13NC-3 3/4-10NC-3 3/4-10 NC-3Gr. 8 1 1/8-7 NC Gr. 8 1 3/8-6 NC Gr. 8 1 3/8-6 NC Gr. 8
Quantity 6 6 12 12 16 16
Torque, Lubed 60 (81) 150 (203) 150 (203) 500 (677) 750 (1016) 750 (1016)
Mounting Size 1/2-13 NC-2Gr. 8 5/8-11NC-2Gr. 8 5/8-11NC-2Gr. 8 5/8-11NC-2Gr. 8 1-8NC Gr. 8 1 3/8-6NC Gr. 5
Screw Quantity 4 6 10 10 14 14
Torque, Lubed 70 (95) 150 (203) 150 (203) 150 (203) 660 (895) 1100 (1490)
2.2.4 Heat the gear uniformly to 250oF (121oC) to expand
the bore and ease assembly. Press the gear onto
the shaft, making sure that the dimension between
the gear and the WCB2 tensioner/brake assembly
mounting surface ("A") is maintained. See Figure 1
and Table 3. Allow the gear to cool.
2.2.5 Apply a thin coat of MOLUB-ALLOY 936 SF HEAVY
or equivalent grease to the splines of the gear.
Caution
Excessive lubricant may contaminate friction
material, resulting in erratic response or loss of
torque.
Caution
The use of anti-seize or bearing greases on the
gear splines may result in premature gear and
disc spline wear.
2.2.6 Pre-ll the grease channel in the friction disc splines
(if applicable) with MOLUB-ALLOY 936 SF HEAVY or
equivalent grease, as shown on Figure 4.
2.2.7 Rig the WCB2 tensioner/brake assembly into position
and slide it over the gear.Avoid placing lifting straps
or cables directly on the release springs (34).
CHANNEL IS FILLED WITH
MOLUB-ALLOY 936 SF
HEAVY GREASE
.12" (3.0 mm)
Figure 4
WCB2 Tensioner/Brake

EATON WCB11070 WCB2 Tensioner/Brake Installation, Operation and Maintenance Manual E-CLCL-II016-E December 201610
2.2.8 Attach the mounting ange (1) to the mounting
surface using the appropriate fasteners.
If applied pressure was used to help position the
friction disc assemblies during mounting, exhaust
the air pressure prior to tightening the fasteners.
Tighten the fasteners to the specied torque value.
See Table 4.
Caution
Maximum allowable air pressure in the cylinder (19)
is 150 psig (10.2 bar).
2.2.9 WCB2 tensioner/brake assembly should be covered
to protect the unit from dirt, rain, overspray, and
other sources of external contamination. In extreme
environments the use of a sealed enclosure with
internal strip heater is recommended to prevent
moisture from collecting on the unit.
2.3 Air System
Warning
Maximum allowable air pressure is 150 psig (10.2
bar). Application of pressure exceeding maximum
allowable may result in damage to the WCB2
tensioner/brake assembly.
2.3.1 Maximum allowable pressure is 150 psig (10.2 bar).
2.3.2 Use only clean, ltered air (a 50 micron lter or better
is recommended) which is free of excess moisture.
2.3.3 Air inlet sizes are shown in Table 5. Air inlets are
located on the face of the cylinder (19). For cylinders
with three ports, the lowest port should be located at
or near the 6 o'clock position to facilitate purging of
moisture that may accumulate in the air system
or cylinder.
Table 5
Air Inlet Size
Size Thread Size
8WCB2 3/8"-18 NPT
14WCB2 1/2"-14 NPT
18WCB2 1/2"-14 NPT
24WCB2 1/2"-14 NPT
36WCB2 3/4"-14 NPT
48WCB2 1"-11.5 NPT
2.3.4 All pipes should be free of metal chips, cutting
compound and any other foreign matter. Pipe ends
should be reamed after cutting to eliminate possible
restrictions. For optimum air system response, a
minimum number of bends and elbows should
be used.
2.3.5 The WCB2 tensioner/brake assembly does not
require lubricated air; however associated control
valves may. Consult the valve manufacturer for
appropriate recommendations.
2.4 Coolant System
Caution
Make sure that the water inlets and outlets are
positioned as close as possible to the 6 o'clock and
12 o'clock positions, respectively. This will help to
minimize the formation of air pockets in the water
cavity during operation, which could contribute to
overheating of the WCB2 tensioner/brake assembly.
2.4.1 Maximum allowable coolant pressure within the
water cavity is water cavity is 40 psig (2.7 bar) for
36WCB2 and 48WCB2 tensioner/brake assemblies
and water cavity is 45 psig (3.1 bar) for all other
WCB2 tensioner/brake assemblies. See Table 6
for coolant pressure limitations as measured at the
inlets and outlets of water jackets. Note that inlet
pressures exceeding the maximum allowable static
pressures are only permissible under dynamic ow
conditions, provided that the average pressure
between the inlet and outlet does not exceed the
maximum allowable pressure stated above. The use
of an accumulator or pressure relief valve may be
desirable to reduce the effect of pressure spikes in
the coolant system during operation.
Caution
High outlet pressures or surges exceeding
maximum allowable may result in damage to the
WCB2 tensioner/brake assembly.
Caution
Maximum allowable water pressure is dependent
upon WCB2 tensioner/brake assembly's size and
specic application requirements.
Caution
Inlet pressures exceeding the maximum allowable
average pressure are only permissible when the
outlet pressures are at or below the limits listed in
Table 6.
2.4.2 The coolant supply and discharge hose, pipe and
tting sizes, along with minimum ow rates for the
WCB2 tensioner/brake assembly's rated horsepower,
are listed in Table 7.
WCB2 Tensioner/Brake