Page 42 - Compression Machinery for Oil and Gas

34 SECTION II Types of Equipment

FIG. 3.2 Photo of a barrel-style casing with bundle removed. (Courtesy of Solar Turbines, Inc.)

FIG. 3.3 Horizontally split casing.

One advantage of the horizontal split casing design is the easy access to the
compressor internals from overhead after the lid is removed. This feature is
especially useful when the compressor is used as a drive-thru unit having
one or more compressors attached at the nondrive end.

Hermetically Sealed
A hermetically sealed inline compressor as shown in Fig. 3.4 is unique in that
the driver is located inside of the pressure containing casing. The driver in a
hermetically sealed compressor is a high-speed motor since there are no gears.
Although the motor cavity may be at a reduced pressure or purged with helium