IMPROVED PORTED GATE VALVES, METHOD AND APPARATUS

摘要

An improved gate valve comprising spaced parallel housing walls having axially aligned apertures therethrough and constituting a housing; sleeves removably coupled to the housing walls and defining an annular space therebetween; a gate plate in sliding contact with the sleeves reciprocable between open and closed positions and defining a primary seal to atmosphere between the gate plate and sleeves; packing located adjacent to the upper edges of the housing walls through which the gate plate reciprocates between open and closed positions and defining a secondary seal to atmosphere between the gate plate and the packing; and means associated with the periphery of the housing walls to retain flowing fluid within the housing walls.