Doosan G20E-5, Operation & Maintenance Manual, Page: 188 / 210

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Maintenance Section Maintenance Section
Transmission Oil, Oil Filter & Transmission Oil, Oil Filter &
Strainer - Check, Clean, Change
Strainer - Check, Clean, Change
See topic, “Transmission Oil, Oil Filter & Strainer- See topic, “Transmission Oil, Oil Filter & Strainer-
Check, Clean, Change” in “First 50 - 100 Service
Check, Clean, Change” in “First 50 - 100 Service
Hours”
Hours”
Lift Chains - Test, Check, Adjust Lift Chains - Test, Check, Adjust
Lift Chain Wear Test Lift Chain Wear Test
Inspect the part of the chain that is normally Inspect the part of the chain that is normally
operated over the cross head roller. When the
operated over the cross head roller. When the
chain bends over the roller, the movement of the
chain bends over the roller, the movement of the
parts against each other caus
parts against each other causes wears. es wears.
Inspect to be sure Inspect to be sure that chain link pins do not extend that chain link pins do not extend
outside of the link hole. If any single link pin is outside of the link hole. If any single link pin is
extended beyond its connecting corresponding link,
extended beyond its connecting corresponding link,
it should be suspected of being broken inside of its
it should be suspected of being broken inside of its
link hole. Lift chains are required to check for wear
link hole. Lift chains are required to check for wear
about every 1,000 service hours or 6 months.
about every 1,000 service hours or 6 months.
Chain wear test is a measurement of wear of the Chain wear test is a measurement of wear of the
chain links and pins. Take the following steps to chain links and pins. Take the following steps to
check chain wear. check chain wear.
1. 1. Lift the mast and carriage enough for getting Lift the mast and carriage enough for getting
tension on lift chains.
tension on lift chains.
Typical example Typical example
2. 2. Measure precisely ten links of chain distance at Measure precisely ten links of chain distance at
the center of pins in
the center of pins in millimeter. millimeter.
3. 3. Calculate chain wear rate*. Calculate chain wear rate*.
4. 4. If the chain wears rate is 2% or more, replace If the chain wears rate is 2% or more, replace
the lift chain.
the lift chain.
*Chain wear rate (%) *Chain wear rate (%)
= = Actual Actual measurement measurement - - Pitch** Pitch** X X 10 10
Pitch** X 10 Pitch** X 10
**Chain Pitch = 19.05mm (0.75in) **Chain Pitch = 19.05mm (0.75in)
Check for Equal Tension Check for Equal Tension
Typical example Typical example
Lift the carriage and the mast high enough for Lift the carriage and the mast high enough for
getting tension on lift chains. Check the
getting tension on lift chains. Check the chains, and chains, and
make sure the tension is the same. Lift chains are make sure the tension is the same. Lift chains are
required to check for equal tension about every
required to check for equal tension about every
1,000 service hours or 6 months.
1,000 service hours or 6 months.
WARNING WARNING
Personal injury can be caused by sudden Personal injury can be caused by sudden
movement of the mast and carriage. Keep
movement of the mast and carriage. Keep
hands and feet clear of
hands and feet clear of any parts that can move. any parts that can move.
Lift Chain Adjustment Lift Chain Adjustment
Typical example for carriage eq Typical example for carriage equal tension ual tension
If the tension is not the same on both chains, take If the tension is not the same on both chains, take
the procedure as
the procedure as follows. follows.
NOTE: NOTE: If carriage height is not correct, make If carriage height is not correct, make
adjustments by following procedures. adjustments by following procedures.
X 100 X 100