WÄRTSILÄ PAAE051728, Instruction Manual

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The connecting rod is forged and machined of alloyed steel and
is splitted horizontally in three parts to allow removal of piston
and connecting rod parts. All connecting rod bolts are hydrauli-
cally tightened to minimize the relative movements between
mating surfaces.
The big end bearings are fully interchangeable trimetal or
bimetal half shell bearings.
The pistons are fitted with a Wärtsilä patented skirt lubricating
system. The top ring grooves are hardened. Cooling oil enters the
cooling space through the connecting rod. The cooling spaces are
designed to give an optimal shaker effect.
The piston ring set consists of two chrome-plated compression
rings and one chrome-plated, spring-loaded oil scraper ring.
The cylinder head, made of nodular cast iron, is fixed by four
hydraulically tensioned screws. The head is of the double deck
design and cooling water is forced from the periphery towards the
centre giving efficient cooling in important areas.
The inlet valves are stellited and the stems are chromium-
plated. The valve seat rings are made of a special cast iron alloy
and are changeable.
The exhaust valves , with Nimonic or stellite seats and chro-
mium-plated stems, seal against the directly cooled valve seat
rings.
The seat rings, made of a corrosion and pitting resistant mate-
rial, are changeable.
The camshafts are made up from one-cylinder pieces with
integrated cams.
The engine is available with two different fuel injection systems:
common rail fuel injection and conventional fuel injection .
·
The common rail system consists of one fuel oil high pres-
sure pump and one fuel accumulator per two cylinders.
·
The conventional fuel system consists of injection pumps
that have separated roller followers and can be changed by
adjusting the base measure with the tappet screw.
The pumps and piping are located in a closed space which
is heat insulated for heavy fuel running.
The turbocharger is normally located at the free end of the
engine.
The charge air cooler is of a self-supported type.
The lubricating oil system includes a gear pump, automatic
oil filter, centrifugal filter for cleaning the back-flush oil, cooler
with thermostat valve and an electrically driven prelubricating
pump.
The oil sump is dimensioned for the entire oil volume needed,
and all cylinder numbers can be run in wet sump configuration.
Dry sump running is also possible.
The starting system. The air supply to the cylinders is control-
led by a starting air distributor run by the camshaft.
01 Main Data, Operating Data and General Design 32-200634-01
01 - 4 WÄRTSILÄ 32