Calculation features of lubrication-free labyrinth seals for a reciprocating compressor of boil-off gas

The objective of this article is to review and select suitable calculation methods for labyrinth seals in piston compressors used for compression of low-temperature liquefied natural gas vapors (boil-off gas) generated during liquefied natural gas transportation and storage. This article examines existing labyrinth seal designs for various power and compressor equipment. Various design and calculation methods for labyrinth seals in industry are considered. The article analyzes known calculation methods for labyrinth compressor seals and various designs of labyrinth compressor seals for use in piston compressors for unlubricated gas compression. The factors determining the widespread use of labyrinth piston compressors are considered. The article considers a piston compressor, which is part of a complex of compressor equipment for the production and storage of liquefied natural gas, and in particular the seals used in them. The main result obtained is the development of a methodology for estimating leakage through a labyrinth seal with grooves of varying pitch and profile. Recommendations for the design of sealing elements for piston labyrinth compressors are developed. Optimal parameters for labyrinth seals in piston compressors for efficient compression of boil-off gas in compressor equipment for the production and storage of liquefied natural gas have been determined. In piston boil-off gas compressor designs, labyrinth grooves can be implemented on both the piston and the cylinder, so it is advisable to conduct further research to obtain blowdown data for such seals.
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