Komatsu D155AX-8E0, Руководство по эксплуатации и техническому обслуживанию

Страница: 185 / 420

Komatsu Closed Crankcase Ventilation (KCCV)
KCCV (Komatsu Closed Crankcase Ventilation) is a device to
clean the gas discharged from the engine crankcase with the
filter element and return it to the engine air intake system.
NOTICE
• The KCCV filter element needs to be replaced every
2000 hours. For details of the replacement procedure,
see “METHOD FOR REPLACING KCCV FILTER ELE-
MENT (4-73)”.
• If the engine is operated without KCCV filter element
or if a filter element other than the Komatsu genuine
one is used, the engine sucks oil and foreign material
which can cause a failure. Always install Komatsu
genuine KCCV filter element.
• The filter element cannot be flushed. Never reuse the
filter element since it can cause a performance decre-
ment of engine, and it result in a failure even if it is
cleaned.
HANDLE UREA SCR SYSTEM WARNING
Urea SCR system is a device which converts toxic nitrogen oxides (NOx) in the exhaust gas into harmless nitro-
gen and water. By spraying DEF into the exhaust gas, it decomposes and hydrolyzes to form ammonia (NH3)
and the ammonia selectively reacts with nitrogen oxides for the conversion to nitrogen and water.
The Komatsu Urea SCR System continuously monitors its operation conditions and stores information on inap-
propriate operations including malfunctions. The information is used for system diagnostics and also for Induce-
ment required by the authorities on engine systems that use Urea SCR systems. Inducement is intended for the
operator to take prompt actions to maintain and correct inappropriate behaviors of Urea SCR systems by utiliz-
ing visible and audible alerts, and engine power derate in addition. Alerts in Inducement of the Komatsu Urea
SCR System progresses step by step starting from visual indications on the machine monitor and audible
sounds to engine power derate to avoid getting into unsafe conditions.
The Komatsu Urea System also monitors recurrences of abnormalities of the system. Inducement in the recur-
rences is activated when another abnormality occurs within 40 hours after the first abnormality is fixed.
The Komatsu’s Urea is composed of two major systems, which are the DEF system and the SCR catalyst Ass’y.
OPERATION EXPLANATION OF COMPONENTS
3-123