Patent attributes
A valve assembly includes a valve body and a valve member extending through at least a portion of the valve body. The valve assembly also includes a seat pocket forming an annular recess in the valve body and a seat arrangement positioned at least partially within the seat pocket. The seat arrangement includes a lower seat extending radially inward from the annular recess toward the valve cavity axis. The seat arrangement also includes an upper seat at least partially overlapping the lower seat, the upper seat extending radially inward toward the valve cavity axis to contact the valve member along a seat face. The seat arrangement further includes an interface seal positioned along an interface between the upper seat and the lower seat, the interface seal receiving a fluid pressure to drive the lower seat radially outward and into the annular recess.
