Eaton 146246A, Installation, Operation And Maintenance Manual

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TABLE 8
Maximum Disc Speeds
Size
Max. Slip Speed
RPM
Max. Disc Speed
RPM
8WCB 2150 3580
14WCB 1260 2045
18WCB 955 1600
24WCB 715 1200
36WCB 475 700
pH value of the w ater/ethylene glycol mixture:
7.5. to 10.5.
3.0 OPERATION
3.1 Conditions of Operation
The follow ing Hazard Warnings are to be fol-
low ed 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 per-
sonal 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 significantly reduce the
torque capacity of the unit. Dirt or cool-
ant 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 8. 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.
For proper cooling of the WCB tensioner,
it is required that the coolant inlet be
located at the 6 o’clock position and the
outlet be located at the 12 o’clock
position. This will assure that all coolant
cavities are filled and will prevent
overheating. Refer to Figure 2 & 8.
For operation in subfreezing tempera-
tures, ethylene glycol antifreeze must be
added to the water. The antifreeze
content of the mixture is critical and
should not exceed 50% by volume since
excessive amounts will reduce cooling
capacity and can cause coolant leakage
due to overheating. Refer to Section 2.5
and Table 6.
3.2 Pressure and Speed Limits
3.2.1
Maximum applied air pressure is 150 PSIG
(10.3 bar). Maximum w ater pressure measured
at the inlet of the tensioner is 45 PSIG (3.1 bar).
3.2.2
Maximum slip speeds and (free w heeling) disc
speeds are show n in Table 8.
Excessive slip speeds will result in rapid
friction material wear. For good life, the
values in Table 8 should not be exceeded.
A minimum wear in period of four hours
at 50% of the rated horsepower is
recommended for the friction couple to
achieve rated torque.
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