Abstract: A valve assembly having an inner and outer concentric valve seat. The inner valve seat is arranged radially inward of the outer valve seat to provide an annular opening therebetween. A movable plunger moves between a closed position and an open position to vary a flow restriction at the inner and outer valve seats and simultaneously seal the inner and outer valve seats in the closed position. An inner and outer valve member comprise the inner and outer valve seats and are separate components mounted in fixed relation to one another. The inner and outer valves seats are radially aligned to maintain concentricity of the inner valve seat relative to the outer valve seat and axially aligned to maintain axial alignment of the inner valve seat relative to the outer valve along an axis, wherein the axis is substantially orthogonal to a plane of the inner and outer valve seats.

Abstract: There is provided a valve assembly (100). The valve assembly comprises a valve seat comprising an inner concentric valve seat (104) and an outer concentric valve seat (105), the inner concentric valve seat being arranged radially inward of the outer concentric valve seat to provide an annular opening therebetween. The valve assembly also comprises a movable plunger (107), being movable between a closed position and an open position to vary a flow restriction at the inner and outer concentric valve seats, and arranged to simultaneously seal the inner concentric valve seat and the outer concentric valve seat when in the closed position. The valve assembly also comprises an inner valve member (124) comprising the inner concentric valve seat and an outer valve member (125) comprising the outer concentric valve seat. The inner valve member is a separate component from the outer valve member and is mounted in fixed relation to the outer valve member via mounting means.