Nexen MWCB 830812 - Manual (Page 10)

10
FORM NO. L-20016-X-1209
TROUBLESHOOTING
PROBLEM PROBABLE CAUSE SOLUTION
Failure to engage.
Air not getting to clutch-brake due to a control
valve malfunction. Check for control valve malfunction and replace
valve if necessary.
Air leaks. Replace air lines.
Lack of lubrication on the hub spline or in the
air chamber. Lubricate hub spline and/or air chamber.
Rigid piping instead of flexible air lines. Replace rigid piping with flexible air lines.
Failure to disengage.
Unexhausted air due to a control valve mal-
function. Check for control valve malfunction and replace
if necessary.
Friction lock due to a lack of lubrication on the
hub spline or in the air chamber. Lubricate hub spline and/or air chamber.
Rigid piping instead of flexible air lines. Replace air lines with flexible air line tubing.
Weak or broken compression springs. Replace compression springs.
Loss of torque.
Air leaks. Replace air lines.
Overheating (fading). Check manufacturing specifications to be certain
clutch-brake is suitable for application.
Overlap or simultaneous engagement of clutch
and brake when switching. Overlap can be
verified by motor amperage readings when
cycling with the clutch-brake versus clutch
(brake disconnected). Higher draw with the
clutch-brake indicates overlap. Inadequate controls. Install controls meeting the specification of
clutch-brake.
Air line too long between valve and clutch-
brake. Shorten air line between valve and clutch-brake.
Air pressure too high. Reduce the air pressure.
Lack of quick exhaust valves. Install quick exhaust valves.
FIGURE 4
TyPICAL CLUTCH-BRAKE
Sheave
Ball
Bearing
Hub
Compression
Spring
Friction
Disc
Friction
Facing
Ball
Bearing
Air
Chamber
O-Ring
Seals
Friction
Disc
Ball
Bearing
Piston Air
Chamber
Friction
Facing
Piston
Compression
Spring
Shoulder
Bolt