Fitting for through-wall penetration of a composite vessel

A composite vessel comprising:

• a composite wall forming an internal chamber for containing a fluid, the composite wall having a first through-wall penetration and an exposed end grain at the first through-wall penetration;
• and
• a composite vessel fitting secured to the composite wall at the first through-wall penetration, the fitting comprising a sealing surface arrangement that seals against the composite vessel and protects the end grain from exposure to internal fluid and external environment while preventing leakage of the contents fluid;
• wherein the fitting is non-destructively removable from the composite vessel,
• wherein the composite wall is a fiber-reinforced polymer-matrix composite,
• wherein the fitting includes a fastener-receiver assembly that forms a clamp that exerts forces on opposite inner and outer surfaces of the composite vessel, and
• wherein the fastener-receiver assembly includes a receiver on an inner side of the composite vessel, the receiver formed on an inner part of the fitting, and a fastener that extends through a second through-wall penetration from an outer side of the composite vessel to engage the receiver on the inner side of the composite vessel,
• wherein the sealing surface arrangement includes:
• an outer seal arrangement including at least one outer seal having a first sealing surface that interfaces with the outer surface of the composite vessel and cooperates with an outer part of the fitting to fluidly seal against the outer surface for restricting migration of environmental contaminants to the end grain of the composite vessel;
• an inner seal arrangement including at least one inner seal including:
• a first seal having a second sealing surface, wherein the first seal is disposed in a seal groove of the inner part of the fitting such that the first seal seals an interface between the inner part and the inner surface of the vessel;
• and
• a discrete second seal having a third sealing surface that interfaces between the inner part of the fitting and a through-wall part of the fitting wherein the second seal is disposed in a seal groove of the through-wall part, such that the second seal seals an interface between the inner part and the through-wall part, which the through-wall part extends through the first through-wall penetration of the composite vessel.