Page 233 - Subyek Teknik Mesin - Forsthoffers Best Practice Handbook for Rotating Machinery by William E Forsthoffer

Compressor Best Practices Best Practice 3 .23

Fig 3.23.13 Typical tandem seal system for saturated process gas

Double seal system for dry gas or saturated gas must be used. The seal systems previously shown will be used
application for the supply of conditioned gas to the seals as required by the
condition of the seal gas (dry or saturated).
Figure 3.23.16 depicts a double seal, which is used in either dry
gas or saturated gas applications where the process gas is not
permitted to exit the compressor case. For this application Summary
process gas can be used, after it is conditioned, or an external
source can be used if it is compatible with the process gas. If the Since there are significant advantages to the use of dry gas seals,
gas used between the seals is toxic or flammable, a suitable many units are being retrofitted in the field to incorporate this
barrier seal, provided with nitrogen, as shown in Figure 3.23.10, system. In many cases, significant payoffs can be realized.

Fig 3.23.14 Tandem seal with interstage labyrinth (Courtesy of Flowserve Corp.)

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