Abstract: An essentially fully balanced plug valve is presented in which the flow control contour is interior to the moving member. The sealing edge of the moving member is at the exterior surface relative to the interior contour. This sealing edge is formed by use of matching angles on the interior of the moving member and the exterior of the stationary member. As a result, operation of the plug is fully balanced with the internal fluid pressure of the liquid therein. The sealing surface of the stationary member is positively retained therein to prevent blowout of the sealing surface. Should failure of the sealing surface occur, a secondary metal-to-metal seal will provide fluid containment albeit possibly at a reduced containment level.

Abstract: An essentially fully balanced plug valve is presented in which the flow control contour is interior to the moving member. The sealing edge of the moving member is at the exterior surface relative to the interior contour. This sealing edge is formed by use of matching angles on the interior of the moving member and the exterior of the stationary member. As a result, operation of the plug is fully balanced with the internal fluid pressure of the liquid therein. The sealing surface of the stationary member is positively retained therein to prevent blowout of the sealing surface. Should failure of the sealing surface occur, a secondary metal-to-metal seal will provide fluid containment albeit possibly at a reduced containment level.

Abstract: A precision modulating globe valve for controlling the flow of a fluid from zero to a maximum flow rate. The valve plug of the globe valve includes at least one flow modulating channel recessed from the outer surface of the valve plug. The outer surface of the valve plug engages a sealing member positioned along the inner surface of the valve port. The sealing member provides a fluid-tight seal between the outer surface of the valve plug and the valve port. The flow modulating channel is recessed from the outer surface of the valve plug from a minimum flow end to a maximum flow end. The radially recessed area of the flow modulating channel increases from the minimum flow end to the maximum flow end, such that as the valve plug moves past the stationary sealing member, an increased flow rate is created through the valve port.

Abstract: A precision modulating globe valve for controlling the flow of a fluid from zero to a maximum flow rate. The valve plug of the globe valve includes at least one flow modulating channel recessed from the outer surface of the valve plug. The outer surface of the valve plug engages a sealing member positioned along the inner surface of the valve port. The sealing member provides a fluid-tight seal between the outer surface of the valve plug and the valve port. The flow modulating channel is recessed from the outer surface of the valve plug from a minimum flow end to a maximum flow end. The radially recessed area of the flow modulating channel increases from the minimum flow end to the maximum flow end, such that as the valve plug moves past the stationary sealing member, an increased flow rate is created through the valve port.

Abstract: A stem seal having first and second wiping members circumjacent a stem is disposed within a bore. A lubricant-bearing ring is disposed about the stem within the bore between the wiping members, under compression therefrom. Projections from the wiping members intrude into the lubrication ring so as to depress the central surface areas thereof. Similar projections are used to center a coil spring against one of these seal members and against an additional seal member. By forming the lubricant ring of open-cell loam or mesh construction, superior lubricant bearing capacities may be achieved.