Abstract: A sealing system for high pressure fluid couplings wherein male and female valved coupling parts are interconnected while under fluid pressure, the sealing system including a pair of diverse characteristic seal rings axially spaced in the direction of relative coupling part movement. The seal ring closest to the pressurized medium is semi-rigid to prevent blow-out from its recess during coupling disconnection and interconnection while the second seal ring is of greater elasticity and sealability to prevent leakage. The axial spacing between the seal rings permits adequate internal support for the second seal prior to the opening of the coupling parts' valves.

Abstract: A coupling for use with pressurized systems permitting coupling of valved coupling parts even though one of the parts may be under high pressure. An axially reciprocal valve which automatically opens upon the coupling halves being connected is guided within a shell within the pressurized coupling half and a sealed relationship between the valve and shell minimizes the area of valve surfaces exposed to the pressurized medium reducing the axial forces imposed upon the valve toward the closed position. A bleed valve communicating with the valve interior permits valve operation with hydraulic systems in the event of seal leakage.