@techreport{oai:jaxa.repo.nii.ac.jp:00044909,
 author = {野坂, 正隆 and 鈴木, 峰男 and 宮川, 行雄 and 上絛, 謙二郎 and 菊池, 正孝 and 森, 雅裕 and NOSAKA, Masataka and SUZUKI, Mineo and MIYAKAWA, Yukio and KAMIJO, Kenjiro and KIKUCHI, Masataka and MORI, Masahiro},
 month = {Feb},
 note = {The development of a 10-ton thrust liquid oxygen and liquid hydrogen (LOX and LH2) rocket engine is under way at the National Space Development Agency. In advance of the development of a liquid hydrogen turbopump, the National Aerospace Laboratory carried out study and development of a face-contact, bellows mechanical seal for a liquid hydrogen turbopump in co-operation with the National Space Development Agency. The present report describes the fundamental experiments of the mechanical seal (seal diameter:58.5mm) for liquid nitrogen and liquid hydrogen and the development of the mechanical seal for a liquid hydrogen turbopump (seal diameter:43.2mm). The developed mechanical seal has two features. One is a new type of seal nosepiece, which reduces the sealing face distortion at low temperature and high pressure. It results in a small amount of seal leakage and wear, and a low starting torque. The other feature is a new type vibration damper made of Teflon sheets. Th sheets are fixed in a nosepiece in order to prevent fluttering of the seal nosepiece during the rapid start or stop of a turbopump. Numerous tests were performed to clarify the seal performance. It was confirmed that the developed turbopump mechanical seal satisfied almost all requirements for application to a turbopump: seal leakage, wear life, reliability, starting torqe ,etc.. A long time test of 66 minutes in the condition (fluid pressure: 15 ata, rotating speed: 50,000 rpm, liquid hydrogen coolant flow: 0.4l/sec) was successful. The seal performances of the developed turbopump mechanical seal were as follows: liquid hydrogen leakage in steady state condition was 7.7～19.2cc/min. Wear of seal components after a long time run were 0～8μm in carbon face piece and 0.1μm (maximum) in chromium plate on rotating ring., 資料番号: NALTR0653000, レポート番号: NAL TR-653},
 title = {Study and Development of Face-Contact, Bellows Mechanical Seal for Liquid Hydrogen Turbopump},
 year = {1981}
}