WÄRTSILÄ Vasa R22, Instruction Manual

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components being in contact with combustion gases. Efficient
cooling and a rigid design is best achieved with the “double deck”
design in which the flame plate is relatively thin and the mechani-
cal load is transferred to the strong intermediate deck. The most
sensitive areas of the cylinder head are cooled by drilled cooling
channels optimized to distribute the water flow evenly around
valves and the centrally located fuel injector.
The injection valve is described in chapter 16.
12.1.1 Functions
The flame plate of the cylinder head is a part of the combustion
chamber. During the combustion, the flame plate is exposed to
high pressures and high temperatures. The air flow is governed
by two inlet valves in the flame plate. In a similar way, the
exhaust gas is led from the cylinder through the cylinder head
exhaust channel and to the exhaust manifold. The gas flow is
governed by two exhaust valves.
The multi-orifice injection valve (4), as well as injection valve
sleeve, is centrally mounted in the cylinder head. The injection
valve sleeve holds the injection valve in position and separates
the injection valve from the cooling water.
Each cylinder head is individually cooled by a water flow enter-
ing the cylinder head from the cylinder jacket through one single
bore. There are drilled cooling passages to the exhaust valve seats.
The cooling water is collected to a single flow after passing the
flame plate and the seat rings.
The valve mechanism is lubricated from the lubricating oil
system. The oil is led through a pipe from the valve tappet guide
block to the rocker arm bracket (1). All other flows in the cylinder
head are through drillings.
The controlled leaks of the injection valve is returned through
the protection pipe.
The fuel pipe is also provided with protection against hazardous
leaks from the high pressure connection stud.
12.2 Removing and mounting of the cylinder
head
12.2.1 Removing of the cylinder head
1 Drain cooling water. Remove the cooling water outlet
pipe.
2 Remove the cylinder head cover, the panel covering
the injection pumps and exhaust insulation panel over the
exhaust gas connection to the cylinder head.
3 Remove the exhaust pipe fastening screws.
12 Cylinder Head with Valves 22-9601
12 - 2 VASA 22