Abstract
Long-term experiments of a brush-type seal were carried out in vacuum as a candidate for a regolith seal. The brush made of fluorine resin was rubbed against a seal ring made of anodized aluminum alloy. A labyrinth seal was placed in front of the brush-type seal. The seal ring was rotated 1500 cycles, where 1 cycle consisted of each CW and CCW 40 rotations. Regolith simulant was poured on the seal by means of a rotating drum containing the regolith simulant. Two tests about 1 week duration were conducted. The tests proved that the seal system, the brush-type seal plus the labyrinth seal, showed excellent sealing capability against the regolith simulant and low friction torque. The experiments clearly demonstrated the feasibility of the brush-type seal as a regolith seal
