Accession Number : AD0738642

Title :   Contamination Danger by Oil-Lubricated Ball Bearings in Spacecraft,

Corporate Author : DEUTSCHE FORSCHUNGS- UND VERSUCHSANSTALT FUER LUFT- UND RAUMFAHRT E V BRUNSWICK (WEST GERMANY)

Personal Author(s) : Wilkens,Walter

Report Date : 19 MAY 1971

Pagination or Media Count : 5

Abstract : The weight loss of special oil reservoirs, the sorption of oil on selected materials, and the surface migration of oil were investigated for an oil which has been successfully used for lubricating ball bearings operating in a vacuum environment and selected as one of the promising lubricants for the antenna despin system of the HELIOS spacecraft. The oil loss rates determined cannot be calculated by the relation of free molecular flow and are assumed to be greatly influenced by surface migration phenomena. The adsorption of oil vapor is considerable on ZnO and TiO2 coated surfaces, but is not detectable on glass. Gross surface migration of oil takes place on ZnO and TiO2-coatings which are in direct contact with oil whereas there is no surface migration detectable on these surfaces when the oil is in a porous reservoir material. (Author)

Descriptors :   (*BALL BEARINGS, LUBRICATION), (*SPACECRAFT, BALL BEARINGS), SOLAR SATELLITES, OILS, FAILURE, HAZARDS, ADSORPTION, WEST GERMANY

Subject Categories : Lubricants and Hydraulic Fluids
      Machinery and Tools
      Unmanned Spacecraft

Distribution Statement : APPROVED FOR PUBLIC RELEASE