Installation Manual
N40475 Chapter 4
Page 11
Dry systems
Dry exhaust systems for marine installations need
careful design to minimize the disadvantages of
enclosing components that are at a high temperature
in conned spaces.
The rst part of a dry system should include a exible
connection so that excessive weight is not carried
by the connection to the engine. Connections of the
stainless steel bellows type are suitable, but care
must be taken to ensure that they are only required to
accommodate movements that do not involve twisting
the ends of the bellows relative to each other.
The remainder of the exhaust system should be well
insulated to avoid re risk.
If there is a long exhaust run which gains height as it
leaves the engine, it may be necessary to incorporate
a trap to collect condensate and allow it to be drained.
Figures 4 shows a typical system. The minimum bore
of the exhaust pipe should be 85mm (3.34 inches).
(1) Bracket with link to allow for movement due to
expansion in the exhaust system (horizontal exhaust
systems should be suspended from the deck head
using similar brackets - rigid brackets should not be
used).
(2) Insulating lagging.
(3) Rigid bracket to support the weight of the vertical
exhaust system.
(4) Heat blanket.
(5) Twin stainless steel bellows tted to avoid torsional
load on bellows unit.
(6) Heat blanket.
(7) Turbocharger adaptor.
(8) Heat blanket.
(9) 90
O
Elbow.
Note: When tted, the bellows units should be in
an unstrained condition so that the full bellows
movement is available to absorb expansion and
engine movement.
Figure 4