Wärtsilä Medium-Speed Marine Diesel Engines

Lubricating
oil
cooler
Charge
air cooler
LT
Heat recovery
Charge
air cooler
HT
Cyl.
Central
cooler
LT
stand­by
pump
LT
pump
HT
pump
HT
stand­by
pump
Preheater
PRINCIPLE LAYOUT OF THE COOLING SYSTEM.
Automatic filter
Oil cooler
Oil pump
Electric
stand­by
oil pump
Centrifugal filter
Electric
pre­lube
oil pump
Dry oil sump
Suction
strainer
System oil tank
PRINCIPLE LAYOUT OF THE LUBRICATING SYSTEM.
COOLING SYSTEM
The cooling system on the engine is split
into two separate circuits: high-temperature
(HT) and low-temperature (LT). The cylinder
liner, the cylinder head, and the first stage
in the charge air cooler are all connected to
the HT circuit. The lubricating oil cooler and
the second stage in the charge air cooler are
connected to the LT circuit.
The amount of water passing through the
LT stage in the charge air cooler is controlled
by a thermostatic valve. This maintains the
desired intake air temperature, regardless of
load level or variations in the cooling water
temperature. Engine-driven pumps and builton
thermostatic valves are standard. As an
option, the engine is also available without
built-on pumps and thermostatic valves.
LUBRICATING OIL SYSTEM
The engine is available with a complete builton
lube oil system that offers the following
features:
•An engine-driven main lube oil pump (screw
type) with built-in safety valve
•A pressure regulating valve that keeps the
pressure before the main bearings at a
constant level
•A lubricating oil module, including lube oil
cooler, filter and thermostatic valves
•The lube oil filtration is based on a full flow
automatic back-flushing filter. This requires
a minimum of maintenance and needs no
disposable filter cartridges
•A centrifugal filter connected to the backflushing
line of the automatic filter. This
enables wear particles from the system to
be extracted
•An electric motor driven pre-lubricating
pump, depending on engine configuration
•The oil sump is either a wet or dry type,
depending on engine configuration. A
separate system oil tank is needed for the
dry sump
•Connections for stand-by auxiliaries.
AUTOMATION SYSTEM
Wärtsilä engines can be equipped with a
modular embedded automation system, the
Wärtsilä Unified Controls – UNIC, which is
available in three different versions. The basic
functionality is the same in all versions, but
the functionality can be easily expanded to
cover different applications. UNIC C1 and
UNIC C2 are versions applicable for engines
with conventional fuel injection, whereas UNIC
C3 additionally includes fuel injection control
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