Doosan 10/215HA, Руководство по эксплуатации и техническому обслуживанию

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62 OPTIONS
9/235HA, 10/215HA
DESCRIPTION
Chalwyn valves provide emergency overspeed shutdown protection
for diesel engines and are the most effective way of preventing a
runaway situation. The valves completely block the engine air intake
system, cutting off an uncontrolled external fuel source and the air
required to keep the engine running.
Once the Chalwyn valve is installed, adjustment of the overspeed trip
setting is carried out using the adjuster and locknut (refer to diagram).
Basically rotating the adjuster clockwise will increase the engine speed
at which automatic shut down occurs.
1. Start engine. Slowly accelerate. Note speed at which shut down
occurs.
2. Remove hose at air inlet to Chalwyn valve to expose the adjuster
and locknut (see diagram).
3. Release locknut. Turn adjuster clockwise one turn. Tighten locknut.
4. Refit inlet hose to Chalwyn valve.
5. Start engine. Slowly accelerate. Note speed at which shut down
occurs.
6. Repeat the above steps ’2’ to ’5’ until the first setting at which the
engine does not shut down at high idle speed (i.e. maximum
throttle, no load).
Then either:
a) Use the results of shut down speed versus adjuster setting as a
calibration check to make a final adjustment to give the required setting
(typically 10% to 15% over high idle).
or
b) If a very precise setting is not required, turn the adjuster a further one
turn clockwise to take the shutdown above high idle speed by a
suitable margin. When using this setting procedure it may be found that
the engine occasionally shuts down during the normal operation. If so,
turn the adjuster clockwise by a further one half turn.
7. Ensure the adjuster locknut is fully tightened.
(Use a thread lock adhesive on the locknut threads).
MAINTENANCE
Three monthly
1. Disconnect intake pipework and release the valve from any support
brackets etc. to allow it to be removed.
2. Inspect the valve internally for cleanliness. If necessary, clean in
paraffin or white spirit taking normal precautions. Dry the valve
thoroughly.
3. Check there is no excessive wear and that the valve moves
smoothly over its complete operating stroke. DO NOT LUBRICATE.
4. Refit valve. Check valve setting based on the ’Adjustment’
instructions given herein.
OPTION - OVERSPEED (CHALWYN) VALVE
A Adjuster
B Locknut
C Hold with spanner when adjusting
D Air flow
NOTES:
Turbocharged Engines -
When setting up a valve on a
turbocharged engine using the preceding method, it may be found
that at high power outputs, the engine will shut down at a lower speed
than required. If this occurs, further small adjustments in steps of one
half turn clockwise should be made until the problem is eliminated.
Jammed Valve - If in the course of adjusting the valve it jams on its
seat, release by turning CLOCKWISE viewed from adjuster end of
valve.
NOTE: The three monthly routine maintenance period requirement is
dependent on the operating conditions to which the equipment is
exposed and, by experience, may need to be varied.