| abstract |
Valve having improved resistance to wear and damage of black powder comprising a valve body defining a flow passage therein, an upper cover assembly defining a stem opening, and a rod passing through the stem opening . The valve also includes an elongate door having a proximal end operably attached to the shaft, a distal end, a dimensioned port, and adapted to allow substantially unopposed passage of material through the gate when the port is aligned with the passageway of the valve body, the orifice being located proximate the proximal end of the door, and a solid portion sized and adapted to substantially completely block the flow of material through the door when the solid portion is aligned with the flow passage of the valve body, the solid portion being located distal to the orifice so that the orifice is located between the proximal end and the solid portion. |