Improved internal seals for pipeline centrifugal compressors

Technical Report · Tue May 31 04:00:00 EDT 1988

OSTI ID:5483813

Shapiro, W; Lee, C

Internal labyrinth seals are used extensively in pipeline compressors as impeller inlet seals, interstage seals, and balance piston seals (for beam-type machines). The purposes of this program were to determine the effects on compressor performance of internal seal leakage, consider variations in labyrinth configurations to improve performance, and determine the feasibility of other types of seals that might provide improved performance. In addition, rotordynamic studies of an overhung machine were conducted to establish whether unbalance response was sufficient to cause seal contact and consequent wear. The program involved consultation with both users and manufacturers of pipeline compressors to obtain information regarding the nature of problems, description of the machinery and seal configurations, operating conditions, contemporary design procedures, and advanced seal developments. The results indicated that internal leakage can significantly reduce compressor efficiency; in some machines as much as 3 to 6%, depending on seal clearance. Optimized step seal geometries will provide improved performance, especially for seals that have worn from rubbing contact. A principal problem is seal wear that results from compressor surge. During normal operation, impeller motions are constrained within seal clearances, but when surge occurs severe rubbing can take place. Abradable seals do not address the surge wear problem, except that wear may take longer since abradable seals start out with tighter clearances. A variety of advanced concepts were considered. The most promising are resilient labyrinths that can elastically respond to impeller movements created by compressor surge without excessive damage or wear. 10 refs., 74 figs., 24 tabs.

• Research Organization: American Gas Association, Inc., Arlington, VA (United States). Pipeline Research Committee; Mechanical Technology, Inc., Latham, NY (United States)
• Sponsoring Organization: AGA; American Gas Association, Inc., Arlington, VA (United States)
• OSTI ID: 5483813
• Report Number(s): AGA-91014478; PR--195-721; CNN: PR-195-721
• Country of Publication: United States
• Language: English

Related Subjects

03 NATURAL GAS
032000 -- Natural Gas-- Transport
Handling
& Storage
42 ENGINEERING
420205* -- Engineering-- Transport & Storage Facilities-- (1980-)
ALLOYS
ALUMINIUM ALLOYS
CENTRIFUGAL PUMPS
COMPRESSORS
DOCUMENT TYPES
ENERGY SOURCES
FLUIDS
FOSSIL FUELS
FUEL GAS
FUELS
GAS FUELS
GASES
LEAKS
NATURAL GAS
PIPELINES
PRESSURE DROP
PROGRESS REPORT
PUMPS
SEALS
WEAR