Jacket Cooling Water System - Man B&W S80ME-C7 Project Manual

MAN B&W

Jacket Cooling Water System

Fig. 12.05.01: Jacket cooling water system
The jacket cooling water system is used for cool-
ing the cylinder liners, cylinder covers and ex-
haust valves of the main engine and heating of the
fuel oil drain pipes, see Fig. 2.05.0.
The jacket water pump) draws water from the
jacket water cooler outlet and delivers it to the
engine.
At the inlet to the jacket water cooler there is a
thermostatically controlled regulating valve, with
a sensor at the engine cooling water outlet, which
keeps the main engine cooling water outlet at a
temperature of 80 °C.
The engine jacket water must be carefully treated,
maintained and monitored so as to avoid corro-
sion, corrosion fatigue, cavitation and scale for-
mation. It is recommended to install a preheater
if preheating is not available from the auxiliary
engines jacket cooling water system.
MAN B&W MC/MCC, ME/ME-B/MEC/MEGI engines
The venting pipe in the expansion tank should end
just below the lowest water level, and the expan-
sion tank must be located at least 5 m above the
engine cooling water outlet pipe.
The freshwater generator, if installed, may be con-
nected to the seawater system if the generator
does not have a separate cooling water pump.
The generator must be coupled in and out slowly
over a period of at least 3 minutes.
For external pipe connections, we prescribe the
following maximum water velocities:
Jacket water ................................................ 3.0 m/s
Seawater ..................................................... 3.0 m/s
MAN Diesel
12.05
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