Hydraulic valve with manual override

A gate valve, comprising:

• a valve body defining a flow path therethrough;
• a gate moveable in said valve body between a valve open position which allows flow through said flow path and a valve closed position which blocks flow through said flow path;
• a manual operator stem, said manual operator stem comprising a first shaft portion and a second shaft portion, said first shaft portion comprising a cross-section with a metallic boundary, said metallic boundary enclosing an unobstructed internal space extending longitudinally therein, said first shaft portion being connected to said second shaft portion, said second shaft portion comprising a solid metallic cross-section, said solid metallic cross-section comprises an outer periphery with flat sides that longitudinally extend along a substantial portion of said outer periphery of said second shaft portion;
• a ball screw operatively connected to said manual operator stem, said first shaft portion terminating with said ball screw at one end and being connectable to a manual operator at an opposite end of said first shaft portion;
• a hydraulic actuator comprising a piston and a piston cylinder, said ball screw being positioned outside of said piston cylinder;
• a first piston shaft, an interconnection of said first piston shaft, said manual operator stem and said ball screw being configured so that translational movement of said piston of said hydraulic actuator is transformed into rotational movement of said manual operator stem and rotational movement of said manual operator stem is transformed into translational movement of said piston;
• and
• a second piston shaft on an opposite side of said piston from said first piston shaft, said second piston shaft being operatively connected to said gate.