RADU MIREA, MIHAIELLA CRETU EXPERIMENTAL ASSESSMENT OF PAO AND PAG BASED OIL PERFORMANCES IN A SCREW COMPRESSOR
The paper presents comparative results of an experimental assessment for behaviour and performances evolution of poly-alpha-olefin (PAO) and poly-alkyl-glycol (PAG) based oil, used in a natural gas screw compressor. Within such compressor type the oil is directly injected and has simultaneous multiple roles: lubrication, coolant, compressing and sealant. Taking into account the gas composition, the oil type used within the screw compressor directly influences its performances and life span. For a known composition of processed the gas, the PAO and PAG oil was used in the same compressor. Each type of oil has been monitored and specifically analyzed: flash point determination, cinematic viscosity measurement, FTIR analysis for contamination and usage determination. The literature highlights that a thorough monitoring and analyze of the oil is, in fact, one of the most important ways to assess the performances and usage of a screw compressor. Thus, many of the compressor maintenance problems can be identified and solved resulting the increase of its lifespan and decrease of the maintenance expenditures. The data have been centralized and a comparative analysis of PAO and PAG has been made, thus resulting the best solution for the specific problem encountered at the natural gas shaft.
Keywords: Poly-alkyl-glycol (PAG), poly-alpha-olefin (PAO), mass spectroscopy, FTIR analysis, flash point, kinematic viscosity