15.2.2
Resilient mounting
In order to reduce vibrations and structure borne noise, main engines can be resiliently mounted on rubber
elements. The transmission of forces emitted by the engine is 10-20% when using resilient mounting. For
resiliently mounted engines a speed range of 500-750 rpm is generally available, but cylinder configuration
18V is limited to constant speed operation (750 rpm) and resilient mounting is not available for 7L32.
Two different mounting arrangements are applied. Cylinder configurations 6L, 8L, 12V and 16V are mounted
on conical rubber mounts, which are similar to the mounts used under generating sets. The mounts are
fastened directly to the engine feet with a hydraulically tightened bolt. To enable drilling of holes in the
foundation after final alignment adjustments the mount is fastened to an intermediate steel plate, which is
fixed to the foundation with one bolt. The hole in the foundation for this bolt can be drilled through the engine
foot. A resin chock is cast under the intermediate steel plate.
Cylinder configurations 9L and 18V are mounted on cylindrical rubber elements. These rubber elements
are mounted to steel plates in groups, forming eight units. These units, or resilient elements, each consist
of an upper steel plate that is fastened directly to the engine feet, rubber elements and a lower steel plate
that is fastened to the foundation. The holes in the foundation for the fastening bolts can be drilled through
the holes in the engine feet, when the engine is finally aligned to the reduction gear. The resilient elements
are compressed to the calculated height under load by using M30 bolts through the engine feet and distance
pieces between the two steel plates. Resin chocks are then cast under the resilient elements. Shims are
provided for installation between the engine feet and the resilient elements to facilitate alignment adjustments
in vertical direction. Steel chocks must be used under the side and end buffers located at each corner if
the engine.
Figure 15.5
Principle of resilient mounting, in-line engines (2V69A0247a)
136
Product Guide Wärtsilä 34DF - 3/2012
Product Guide
15. Foundation
