Abstract: A two stage exhaust gas recirculation (EGR) valve delivers a wide range of EGR flow while operating with reduced valve actuating forces allowing use of a reduced cost actuator such as a solenoid with smaller sized coil and armature. An attached valve body mounts concentric dual pintle valves including a larger first valve, which engages a valve seat in the valve body to control exhaust gas flow between inlet and outlet openings and a smaller second valve positioned inside the first valve and engaging a second valve seat in the head of the first valve. The second valve controls a low flow passage inside the first valve. The solenoid armature engages only the smaller second valve during a first stage of its stroke so that the smaller valve is opened first and flow control is maintained in a low flow range. Exhaust and intake differential pressures acting on the second valve are overcome by a smaller armature force because of the smaller area of the second valve.

Abstract: Relatively simple partially or completely pressure balanced valves are disclosed having relatively low friction and gas forces to be overcome by a solenoid actuator. Various devices are provided for sealing of the valve members to maintain low leakage of gases through the valve or into the actuator. Movable members of the valve and actuator are engaged but physically separate so they may be separately replaced. Various actuators may by applied with various valve assemblies for flexibility in meeting the requirements of alternative applications.