WCB 11060 (PDF Format)
12
© Copyright Eaton Corp., 1998. All rights reserved
June, 1998
Dynamic Flow Test:
Dynamic flow testing of the tensioner should
be conducted at the required flow rate for
the rated HP dissipation and coolant quality,
as given in Table 7. Inlet pressure is not to
exceed 40 PSIG (2.7 bar).
There should be no restrictions on the outlet
side of the brake to cause any back pressure
to the unit. Coolant inlet and hose size should
be as given in Table 7. Check for leakage at
the O.D. and I.D. seal areas.
2.5.5
The coolant supply temperature at the inlet
should be 100
o
F (38
o
C) or lower. The coolant
outlet temperature should not exceed the
values given in Table 8. However, in no event
should there be more than a 50
o
F (28
o
C)
temperature rise between inlet and outlet.
See Table 8 for maximum allowable outlet
coolant temperature with a water/ethylene
glycol mix.
2.5.6
Open Loop Systems
For efficient operation of the WCB, an
adequate supply of filtered fresh water is
required. (See 2.5.1-2.5.2). Excessive water
hardness promotes the formation of scale
deposits, which, in time, will affect the
service life of the WCB unit. Water of high
acidity may cause electrolytic corrosion
between the dissimilar metals used in the
WCB. Water treatment should be considered
if the properties of the water exceed the
following:
Equivalent calcium carbonate content
hardness): Maximum 100 p.p.m.
pH value: 7.0 to 9.0.
2.5.7
Closed Loop Systems
For efficient operation of the WCB in a closed
loop system, ethylene glycol coolant conform-
ing to SAE Standard J1034 should be used.
For preparation of the proper
concentration of a water/ethylene glycol
mixture, use makeup water which is low in
corrosive ions such as chlorides and sulfates.
pH value of the water/ethylene glycol
mixture: 7.5. to 10.5.
3.0
OPERATION
3.1
Conditions of Operation
The following Hazard Warnings are to be
followed for proper WCB functioning:
The maximum recommended
operating air pressure is 150 PSIG
(10.3 bar). Air pressure in excess of
150 PSIG (10.3 bar) will cause high
stress in various parts of the
tensioner. Do not risk personal
injury or damage to the equipment!
Protective means must be used to
prevent rain, water, oil, grease, dirt
or coolant from coming into contact
with the surfaces of the friction discs
(8) or the wear plates (3). Oil or
grease on these parts will signifi-
cantly reduce the torque capacity of
the unit. Dirt or coolant will produce
erratic torque. Do not risk personal
injury or damage to the equipment!
The friction disc assembly (7)
maximum disc speed must not
exceed the speeds listed in Table 9.
Exposure to speeds in excess
of these values may cause the
friction discs to burst and result in
extensive damage to the tensioner
and/or cause personal injury.
Table 8
Maximum Mixture Outlet Coolant Temperature
Water/Ethylene
Glycol Mixture
% by Volume
Maximum Outlet
Coolant Temperature
o
F (
o
C)
100/0
150 (66)
70/30
165 (74)
60/40
165 (74)
50/50
170 (77)
