Shuttle valve assembly

Abstract

A shuttle valve assembly formed with a body having a plurality of nesting housings, an outlet end housing with a fluid signal outlet and a closed end housing. These housings have an aligned axial passageway containing a plurality of tubular spool valve members which are adapted to move axially between opened and closed positions therein individually and in a nested arrangement. Each of the housings has an inlet signal port in communication with the passageway. The nested valve members are moved toward the closed end housing by a primary fluid signal applied to the inlet port on the closed end housing with the primary signal passing to the outlet. A superior fluid signal applied to the inlet port of one of the nested housings, causes the valve member closer to the closed end housing to separate from the remaining nested valve members. As a result this superior signal appears at the outlet. Conversely, the nested valve members are moved toward the outlet end housing by superior fluid signal being applied to the inlet signal port in the closed end housing so that the superior fluid signal appears at the outlet. In a preferred embodiment, the nested housing and spool valve members are identical and may be stacked in any number between the end housings so as to provide multiple input control requirements for the shuttle valve in operation of blowout preventer stacks or the like.