著者

高野 敦 松林 三和子 松田 淑男 高野 千尋 小畑 貴稔 森川 洋

出版者

一般社団法人 日本機械学会

雑誌

日本機械学会論文集A編 (ISSN:18848338)

巻号頁・発行日

vol.79, no.801, pp.682-690, 2013 (Released:2013-05-25)

参考文献数

22

被引用文献数

1

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A high strength bolt fastening system for satellite structures has been developed. This fastening system enables high frictional strength by adopting titanium bolts with high strength and low torque-coefficient, as well as shims with high friction coefficient. Low torque-coefficient of the titanium bolts is achieved by PTFE (Polytetrafluoroethylene) solid-film lubricant, which is coated on the bolts. High friction coefficient of the shim is achieved by surface roughening by etching. To verify the design of the fastening system, long-term preload test, torque-coefficient test and vibration loosening test (Junker's test) were conducted and successfully completed. In addition, the fastening system was applied to a development model of satellite structure and was verified by mechanical environmental tests (static load test, system vibration test and thermal vacuum test). The observation showed no evidence of slip or alignment deviation. Thus, a conventional reamer-bolted-fastening system can be replaced with the developed high strength bolt fastening system that saves manufacturing period of satellites and furthermore enables the satellites to be competitive in terms of cost, delivery and performance.

著者

高野 敦 松林 三和子 松田 淑男 小畑 貴稔 森川 洋

出版者

一般社団法人 日本機械学会

雑誌

日本機械学会論文集A編 (ISSN:18848338)

巻号頁・発行日

vol.79, no.804, pp.1201-1209, 2013 (Released:2013-08-25)

参考文献数

13

被引用文献数

1 2

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Long-term measurement and prediction for Ti-6Al-4V and A286 bolts was conducted. It was pointed out that Ti-6Al-4V indicates significant creep behavior and accumulated large creep strain and thus Ti-6Al-4V can not be applied for preloaded bolts. In addition, preload relaxation due to creep of solid-film lubricants for bolts and fastened aluminum parts were also pointed out. Recently, the authors developed a high strength bolted fastening system for satellite structures with PTFE (polytetrafluoroethylene) solid film lubricated Ti-6Al-4V bolts and aluminum threadedand drilled-hole parts. The authors, hence, measured the preload of the fastening system for 253-days, predicted 30-years later preload, and confirmed that the preload reduction was not harmful.