(46d) Dry Gas Seal and Control System Approach to Meet Today's Turbomachinery Reliability Expectation

Introduction of Dry Gas Seals nearly 30 years ago revolutionized the concept of compressor sealing technology. As the oil and gas marketplace continues to respond to the demand of increased production, there is little argument that compressor reliability and uninterrupted operation are crucial to plant operation. The call for more production requires an increase in speed, pressure and compressor size. These requirements are taxing on existing designs as they are pushing compressors to operate beyond their designed application envelope.

Manufacturers are responding by developing new Dry Gas Seals and system designs to meet these performance requirements. Demands and regulations to reduce emissions and improve compressor reliability have encouraged users to convert their wet compressor sealing devices to a Dry Gas Seal design. As a result, API is considering updating current compressor sealing standards and through a task force is developing new API 692 DGS standards. 

This paper describes the evolution of Dry Gas Seals (DGS) and related compressor systems. It also addresses topics under consideration from   API 692 compressor sealing standards, such as seal type selection, material of construction, components terminology, control system philosophy, seal buffer gas filtration, regulation and monitoring. In addition, the paper features the innovative DGS Condition Monitoring that alerts operators to changes that might adversely affect the performance of their overall system, allowing for the implementation of corrective actions in advance of a potential seal failure.