| 摘要 |
<p>1. A device for observing and/or illuminating the interior of a cryogenic tank in service which contains a liquefied combustible gas at low temparature, characterized in that it comprises a hermically closed tube (1) provided with at least one transparent part (7) forming a porthole, and with means (4, 5) for securing it in an orifice or a section of pipe (2) provided in the wall (3, 8) of the tank to be observed, and in that the tube (1) comprises, on the one hand, observation, (20, 21) and/or illuminating (30) means disposed in the of the gaseous phase of the product present in tube (1) in the vicinity of the transparent part (7), on the other hand, means (11, 12) for introducing a dry, inert gas at a temperature higher than that the tank, and means (13) for evacuating the inert gas.</p> |
