Marine Installation Manual
2022-03
4-45
4 Ancillary Systems
4.5 Fuel gas system
X62DF-S2.0
Free-standing –
Type C tank
Type C tanks are designed using conventional pressure vessel codes for pressure
ranges above 2 bar(g). The most common shapes for this type of tank are cylin
-
drical and bi-lobe, which can be either vertically or horizontally mounted de
-
pending on the available space (
). While the cylindrical shape does
not utilise the available space in an optimal way, the bi-lobe shape utilises the
available space more effectively. The intersecting design of two cylinders makes
use of the space between the two single cylinders, which otherwise would be not
be utilised. No secondary barrier is required for Type C tanks, but instead, gas
leakage detectors are placed in the hold space.
Figure 4
-
28 Section view of different free-standing Type C tanks installed below the
deck
Depending on the arrangement of the vessel, the Type C tank can also be ar
-
ranged top-side (on the deck) if this is preferred (see
). For example,
this could be particularly useful if the hold space is used for other bulk materials.
An advantage to this arrangement is that in the event of any leakage, the gas will
not collect in an enclosed space, and will therefore reduce the risk of hazard.
Figure 4
-
29 Type C tank on the deck of a vessel
Cylinders
Hold space
Hold space
Single cylindrical tanks
Bulkhead
SM-0743
Bi-lobe tanks
LNG
SM-0744