Dry Gas Seal Retrofit.

Abstract

Conventionally lubricated shaft sealing systems have long been known to be unreliable, high in maintenance and in some cases hazardous in centrifugal compressors. Labyrinth sealing systems, while generally low in maintenance, are extremely high in operating costs (product loss and steam costs). Dry gas lubricated sealing systems retrofitted into centrifugal compressors are now recognized as a cost effective means of improving equipment performance. Step by step requirements for a successful retrofit of a centrifugal compressor with dry running gas lubricated seals is presented based upon experience and the review of numerous retrofit projects in which dry gas seals are now operating. A description and the advantages of dry gas seals are provided, along with a feasibility study to determine whether or not a retrofit is technically, environmentally, and economically desirable. A detailed proposal request narrative and steps suggested in awarding the contract are shown. This is followed by installation procedures for the dry gas seals along with the commissioning of the newly retrofitted machine. The significant issues presented are based on actual case histories.