Sealing e.g. composite material wall of a propellant tank of a launch vehicle, comprises introducing a heavy gas at a high pressure against an inner face of the wall prior to the introduction of light gas

摘要

The method comprises introducing a heavy gas (5) having a molecular size strictly greater than a molecular size of a light gas at a high pressure against an inner face (2) of a wall (1) prior to the introduction of the light gas. The wall contains, on the inner face, the light gas at a pressure higher than a pressure (PO) prevailing on an outer face (3) of the wall. The wall is a peripheral wall delimiting a closed enclosure. The wall is a composite material wall with an organic matrix. The wall is a porous wall having pores with a dimension greater than a molecular size of the light gas. The method comprises introducing a heavy gas (5) having a molecular size strictly greater than a molecular size of a light gas at a high pressure against an inner face (2) of a wall (1) prior to the introduction of the light gas. The wall is intended to contain, on the inner face, the light gas at a pressure higher than a pressure (PO) prevailing on an outer face (3) of the wall. The wall is a peripheral wall delimiting a closed enclosure. The wall is a composite material wall with an organic matrix. The wall is a porous wall having pores with a dimension greater than a molecular size of the light gas. The molecular size of the heavy gas is lower than a mean size of the pores of the wall. The pressure and a period of validity of the heavy gas on the inner face depend on a thickness of the wall and the mean size of the pores of the wall. The high pressure of the heavy gas is decreased before the introduction of the light gas. The heavy gas is diazotized. The heavy gas is applied at a high pressure against the inner face of the wall until the heavy gas begins to flee from the outer face of the wall.