Perkins M190C, Руководство по установке

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Chapter 2 N40475
Page 6
Engine bearers
The materials and methods of construction of engine
bearers which have proved to be satisfactory in service
vary to such an extent that it is difficult to lay down
universal guide lines. However, as a rough guide it
can be said the engine bearers should be capable of
supporting a static load of about eight times the weight
of the engine, to cater for the effects of rough seas.
The bearers should be cross connected to give lateral
rigidity, in order to maintain the shaft alignment and
to prevent twisting and racking forces being applied
to the engine.
To enable minimum shaft centre distances to be
achieved in a twin installation, a common centre bearer
supporting the inner mountings of both engines is
sometimes used as shown in figure 6. By this method
shaft centres down to 783mm (31”) may be adopted,
but wider spacing is desirable.
The shaft centres could be theoretically reduced
further, but this would result in the engine accessibility
becoming very restricted, and it would be impossible
to carry out service operations. It should be noted that
if minimum shaft centres are to be adopted, space
must be left in front of and behind the engine to
provide access. A minimum clearance on all sides will
mean that the engine cannot be serviced!
Figure 6