Doing without rubber gaskets

Air lock doors must be sealed when closed to prevent loss of the air in a lunar colony. An alternative to using polymeric gaskets is using glass rope gaskets. The edge of the round door, the door frame and the glass gasket itself should be heated to the temperature at which the glass is pliable. The gasket is forced into the space to be sealed and allowed to cool. This should provide an adequate seal. To open the door the gasket would either be reheated or broken.

In an example of standard operation there would be two silos each with an air lock door on the top and an opening to a horizontal chamber at the bottom. One silo would be for putting beneficiated ilmenite into an oxygen processing plant. For this silo the ilmenite goes in through the top door. The horizontal chamber at the bottom leads to an air lock door allowing the ilmenite to enter the plant. Ilmenite could be moved by a horizontal auger to empty the silo. For the other silo tailings from the plant would be put in the top door of the silo and the horizontal chamber would lead to an air lock door by which the tailings leave the plant. The doors might go through a cycle once every eight hours while the sun shines. Any process for collecting volatiles would require processing inside a pressure vessel, so there would be considerable need for air lock door gaskets.