ExxonMobil, a global producer of finished lubricants launched its new synthetic oil for CO2-cooled industrial refrigeration applications at today’s (19 April) ATMOsphere Europe conference on natural refrigerants in Barcelona, Spain.
Mobil SHC Gargoyle 80 POE is designed specifically to lubricate compressors and is particularly suitable for reciprocating compressors using carbon dioxide as a refrigerant. As a refrigerant, CO2 is used in applications ranging from food preparation and freezing operations to cold storage and marine refrigeration.
Natural refrigerants 'growing in popularity'
“Natural refrigerants are growing in popularity in the refrigeration industry in Europe, and increasingly across the world,” said Andrea Jacobsen, ExxonMobil’s industrial marketing manager for Europe, Africa and the Middle East.
“Our new synthetic lubricant for refrigeration compressors will meet this growing need while also adding a range of equipment-protecting qualities and, according to trials, potentially contributing toward enhanced energy efficiency,” Jacobsen added.
The oil was formulated using polyol esters (POE), a type of synthetic oil, with a view to enhancing lubricity, wear protection capabilities and chemical and thermal stability. It supplements ExxonMobil’s existing range of synthetic lubricants for refrigeration compressors and systems, the Mobil Gargoyle Arctic SHC 200 Series and Mobil EAL Arctic Series.
The three key three qualities of the new lubricant are excellent low-temperature fluidity, in-service viscosity control, and its potential contribution towards system efficiency improvements.
The development of Mobil SHC Gargoyle 80 POE was driven by the projected rapid growth of carbon dioxide as an industrial refrigerant over the next four years.
“ExxonMobil predicts that R744 will be one of the main industrial refrigerants by 2020 and will also feature regularly in light commercial refrigeration operations,” said Jacobsen.
The new lubricant has been carefully formulated to exhibit a range of beneficial properties:
Its high film thickness in the presence of refrigerants is intended to improve compressor protection and shaft sealing compared to mineral oil, potentially extending compressor life, reducing unscheduled downtime and lowering maintenance costs;
Its high viscosity index translates into excellent low temperature fluidity and potential for improved evaporator efficiency;
Its low traction coefficient should potentially contribute towards system efficiency improvements and reduced power consumption compared to mineral oils.
Mobil SHC Gargoyle 80 POE in action
As part of its development, Mobil SHC Gargoyle 80 POE was trialled on four reciprocating compressors over 18 months in a major slaughterhouse in northwestern France.
The abattoir switched to Mobil SHC Gargoyle 80 POE from a conventional polyol ester-based oil and found the new Mobil synthetic lubricant delivered lower oil carter and piston temperatures and lower energy consumption. The customer experienced a reduction in power consumption by up to 2% compared against similar compressor load.
Lower operating oil carter temperatures translate into higher in-service viscosity and oil film thickness, which enhances lubricity and results in improved overall equipment protection and lower wear tendency.