Wartsila ?31DF Series, Product Manual

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Required heating power to heat up the engine, see formula below:
where:
Preheater output [kW] P =
Preheating temperature = 60...70 °C T
1 =
Ambient temperature [°C] T
0 =
Engine weight [tonne] m
eng
=
Lubricating oil volume [m
3
] (wet sump engines only) V
LO
=
HT water volume [m
3
] V
FW
=
Preheating time [h] t =
Engine specific coefficient = 1 kW k
eng =
Number of cylinders n
cyl =
9.2.13.2 Circulation pump for HT preheater (4P04)
Design data:
80...100 kPa (0.8...1.0 bar) Delivery pressure
9.2.13.3 Preheating unit (4N01)
A complete preheating unit can be supplied. The unit comprises:
●
Electric or steam heaters
●
Circulating pump
●
Control cabinet for heaters and pump
●
Set of thermometers
●
Non-return valve
●
Safety valve
9.2.14 Throttles
Throttles (orifices) are to be installed in all by-pass lines to ensure balanced operating conditions
for temperature control valves. Throttles must also be installed wherever it is necessary to
balance the waterflow between alternate flow paths.
9.2.15 Thermometers and pressure gauges
Local thermometers should be installed wherever there is a temperature change, i.e. before
and after heat exchangers etc. in external system.
Local pressure gauges should be installed on the suction and discharge side of each pump.
DBAE248994 9-11
9. Cooling Water System Wärtsilä 31DF Product Guide