WÄRTSILÄ PAAE051728, Инструкция по эксплуатации

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19.4.3 HT thermostatic valve
The HT thermostatic valve is integrated in the pump cover at the
free end of the engine. It is equipped with positive three-way valve
action in which the water is positively made to flow in the direction
required. When the engine is started up and is cold, the HT
thermostatic valve causes all of the water to be positively by-
passed back into the pump, thus providing the quickest warm-up
period possible. After warm up, the correct amount of water is
by-passed and automatically mixed with the cold water returning
from the heat exchanger or other cooling device to produce the
desired HT water outlet temperature. If ever required, the HT
thermostatic valve will shut off positively on the by-pass line for
maximum cooling. The three-way action of the valve allows a
constant water flow through the pump and engine at all times
with no pump restriction when the engine is cold.
No adjustments are ever required on the HT thermostatic valve.
The temperature is permanently set at the factory. The tempera-
ture can be changed only by changing temperature element
assemblies which is easily accomplished by unscrewing the cover.
The HT valve is entirely self-contained, and there are no external
bulbs or lines to become damaged or broken. There are no packing
glands to tighten and no parts to oil.
The power creating medium utilizes the expansion of the ele-
ment contents (2), Fig 19-7, which remains in a semi-solid form
and is highly sensitive to temperature changes. Most of the
expansion takes place during the melting period of approximately
two minutes over a temperature change of approximately 8.5°C.
HT thermostatic valve
1. Screw
2. Screw
5
6
4
3 1 2
3. Cover
4. O-ring
5. Element holder
6. Thermostat element
Fig 19-7
4019049601
32-200050 Cooling Water System 19
WÄRTSILÄ 32 19 - 11