Tribological Property of Alternative Refrigerant R134a in Practical condition

Research Project

Project/Area Number	08650171
Research Category	Grant-in-Aid for Scientific Research (C)
Allocation Type	Single-year Grants
Section	一般
Research Field	設計工学・機械要素・トライボロジー
Research Institution	Nagoya Institute of Technology
Principal Investigator	NAKAMURA Takashi Nagoya Institute of Technology, Faculty of Engineering, Associate Professor, 工学部, 助教授 (40135314)
Co-Investigator(Kenkyū-buntansha)	ITOIGAWA Fumihiro Nagoya Institute of Technology, Faculty of Engineering, Assistant, 工学部, 助手 (20252306) MATSUBARA Tomio Nagoya Institute of Technology, Faculty of Engineering, Professor, 工学部, 教授 (20026032)
Project Period (FY)	1996 – 1997
Project Status	Completed (Fiscal Year 1997)
Budget Amount *help	¥2,000,000 (Direct Cost: ¥2,000,000) Fiscal Year 1997: ¥300,000 (Direct Cost: ¥300,000) Fiscal Year 1996: ¥1,700,000 (Direct Cost: ¥1,700,000)
Keywords	Tribology / Alternative refrigerant / Friction test / Reacted products / Lubricant / Additive / Surface treatment / 新冷媒 / 潤滑剤 / 表面コーティング
Research Abstract	Alternative refrigerant R134a has been used for refrigerator, because CFC-12 destroys ozonosphere. Many tribological trouble came into existence when CFC-12 was exchanged for the alternative refrigerant. Countermeasures, for example, surface treatment, lubricant additives, were taken for trouble, and some problems are still unsolved. It is necessary to measure tibological properties of the alternative refrigerant in a practical condition. In the research for fiscal 1996, a pin-on-ring tribo-tester, which can reproduce a practical condition, was constructed, and preliminary tests were carried out for CFC-12 and HFC-134a. The disk surface is severely worn in the HFC-134a envioronment, especially starved lubricant condition. Surface analyzes show that chlorine in CFC-12 acts as a extreme pressure additive when a contacting point is left in a severe friction condition. In the research for fiscal 1997, effects of refrigerant oils, additives and surface treatment on the tribological property were studied in the starved libricant condition. Mineral oil and synthetic oil (PAG) were tested as the refrigeration oil. Experimental results showed that low affinity of the synthetic oil with a metal surface led the starved lubricant condition. tricresylphosphate (TCP) acted as an extreme pressure additive on behalf of the chlorine of CHC-12. Sn coating was effctive as the surface treatment, and it protect seizure for a long term in the starved lubricant condition. But this effect fell in a condition where the environment included oxygen.