Page 100 - Compression Machinery for Oil and Gas

Centrifugal Compressors Chapter 3 89

FIG. 3.56 Baseplate with compressors, and baseplate with gear and motor. (Courtesy of Elliott
Group.)

FIG. 3.57 AVM fixed and sliding directions to isolate base package deflection from FPSO deck
twist and bending [20].

may allow bolting directly to a steel substructure. In many cases, the baseplate
can be made continuous supporting all bodies in the string.
Baseplates that are used for offshore floating platform applications are
unique. They must be of the continuous design and made especially rigid to
allow for three point mounting. Either antivibration mounts (AVMs) or Gimbal
mounts are used at each of the three locations. AVMs are the most common due
to their high damping and successful application. The top pad of each AVM is
bolted to the base and the bottom pad is bolted to the ship deck. The AVMs
isolate the base package from the vessel hull and deck in two ways
(Fig. 3.57). First, the AVMs are heavily damped, decreasing the amplitude
of base package displacement. Second, the AVMs accommodate sliding and
twisting, which prevent deck and twisting and motion from being transmitted
into the base package [20].