日本語フィールド
著者：Toshifumi Mawatari, Nobuyoshi Ohno, Bo Zhang, Akira Nakajima, Hiroshi Shiomi, Shingo Obara題名：Ball Screw Performance and Film Formation Behavior of Four Multiply Alkylated Cyclopentane (Mac) Base Greases for Space Applications発表情報：Proceedings of 6th World Tribology Congress ページ: 1-4キーワード：Ball Screw, Film Formation Behavior, Four Multiply Alkylated Cyclopentane Base Grease, Space Applications概要：抄録：Using the four kinds of multiply alkylated cyclopentane (MAC) 2001A based greases of R2000, ML, MU and 5200, the states of oil film formation in the conventional ball screw were measured at ground level. The experimental results were compared to those obtained by using the three perfluoropolyether (PFPE) 815Z based greases, and the lubricating performances have been examined. As a result, good oil film formations in the tests with the greases of R2000, MU and ML were observed. While, the oil film formation ability of 5200 grease which showed the good lubricating performance in the thrust ball bearing tests was lower compared with the other MAC 2001A based greases. In order to discuss the difference in the lubricating performances of test greases observed in the ball screw tests, the squeeze film formation ability of advanced space lubricant is examined under impact load by falling bearing steel ball against a flat anvil made of mild steel. As the test lubricants, the base oils of 2001A and 815Z and the same greases as the ball screw tests were employed. In the squeeze film formation tests, the EHL dimple depth and the breakdown of lubricant film were measured. Consequently, it was found that the viscosity of the base oil 815Z containing the acetal group is decreased by subjecting to the high shear rate under the EHL squeeze action. Furthermore, when the states of oil film formation were better, the dimple depth tended to become shallower. The states of lubricant film formation in the impact load tests showed the same tendency as those obtained by the tests using the ball screw in which the collisions of internal balls are easy to occur. From the viewpoints, it was suggested that ML and MG greases are optimum as the lubricant for ball screw with impact load.英語フィールド
Author：Toshifumi Mawatari, Nobuyoshi Ohno, Bo Zhang, Akira Nakajima, Hiroshi Shiomi, Shingo ObaraTitle：Ball Screw Performance and Film Formation Behavior of Four Multiply Alkylated Cyclopentane (Mac) Base Greases for Space ApplicationsAnnouncement information:Proceedings of 6th World Tribology Congress Page: 1-4Keyword：Ball Screw, Film Formation Behavior, Four Multiply Alkylated Cyclopentane Base Grease, Space ApplicationsAn abstract：Using the four kinds of multiply alkylated cyclopentane (MAC) 2001A based greases of R2000, ML, MU and 5200, the states of oil film formation in the conventional ball screw were measured at ground level. The experimental results were compared to those obtained by using the three perfluoropolyether (PFPE) 815Z based greases, and the lubricating performances have been examined. As a result, good oil film formations in the tests with the greases of R2000, MU and ML were observed. While, the oil film formation ability of 5200 grease which showed the good lubricating performance in the thrust ball bearing tests was lower compared with the other MAC 2001A based greases. In order to discuss the difference in the lubricating performances of test greases observed in the ball screw tests, the squeeze film formation ability of advanced space lubricant is examined under impact load by falling bearing steel ball against a flat anvil made of mild steel. As the test lubricants, the base oils of 2001A and 815Z and the same greases as the ball screw tests were employed. In the squeeze film formation tests, the EHL dimple depth and the breakdown of lubricant film were measured. Consequently, it was found that the viscosity of the base oil 815Z containing the acetal group is decreased by subjecting to the high shear rate under the EHL squeeze action. Furthermore, when the states of oil film formation were better, the dimple depth tended to become shallower. The states of lubricant film formation in the impact load tests showed the same tendency as those obtained by the tests using the ball screw in which the collisions of internal balls are easy to occur. From the viewpoints, it was suggested that ML and MG greases are optimum as the lubricant for ball screw with impact load.