Abstract: Apparatus, systems, and methods related to a constant-flow control valve and BTU meter assembly that has a pressure independent, constant-flow control valve assembly connectable to the fluid-based heating or cooling system. A valve stem is connected to a valve member and is rotatable as a unit relative to a valve body to change the position of valve member to change a fluid flow rate through the valve. The valve member's position relative to the fluid path is directly related to the fluid flow rate. Pressure sensors measure the pressure of fluid entering and exiting the valve body. A BTU meter assembly is connected to the valve stem, which is rotatable relative to the BTU meter assembly. A position sensor of the BTU meter assembly detects a rotational position of the valve stem relative to the BTU body.

Abstract: Apparatus, systems, and methods related to a constant-flow control valve and BTU meter assembly that has a pressure independent, constant-flow control valve assembly connectable to the fluid-based heating or cooling system. A valve stem is connected to a valve member and is rotatable as a unit relative to a valve body to change the position of valve member to change a fluid flow rate through the valve. The valve member's position relative to the fluid path is directly related to the fluid flow rate. Pressure sensors measure the pressure of fluid entering and exiting the valve body. A BTU meter assembly is connected to the valve stem, which is rotatable relative to the BTU meter assembly. A position sensor of the BTU meter assembly detects a rotational position of the valve stem relative to the BTU body.

Abstract: A constant-flow control valve and BTU meter assembly that has a pressure independent, constant-flow control valve assembly connectable to the fluid-based heating or cooling system. A valve stem is connected to a valve member and is rotatable as a unit relative to a valve body to change the position of valve member to change a fluid flow rate through the valve. The valve member's position relative to the fluid path is directly related to the fluid flow rate. A BTU meter assembly is connected to the valve stem, which is rotatable relative to the BTU meter assembly. A position sensor of the BTU meter assembly detects a rotational position of the valve stem relative to the BTU body. A controller of the BTU meter assembly determines the fluid flow rate based upon the pressure drop across the valve assembly and the rotational position of the valve stem.

Abstract: A constant-flow control valve and BTU meter assembly that has a pressure independent, constant-flow control valve assembly connectable to the fluid-based heating or cooling system. A valve stem is connected to a valve member and is rotatable as a unit relative to a valve body to change the position of valve member to change a fluid flow rate through the valve. The valve member's position relative to the fluid path is directly related to the fluid flow rate. A BTU meter assembly is connected to the valve stem, which is rotatable relative to the BTU meter assembly. A position sensor of the BTU meter assembly detects a rotational position of the valve stem relative to the BTU body. A controller of the BTU meter assembly determines the fluid flow rate based upon the pressure drop across the valve assembly and the rotational position of the valve stem.

Abstract: In one embodiment, a flow control valve includes a valve body having an inlet, an outlet, a flow passageway coupling the inlet to the outlet, and a cavity with first and second chambers. The valve further includes a hollow piston disposed in the first chamber and a seal separating the first and second chambers. The seal has a section within the piston that is exposed to the fluid in the first chamber. The section of the seal defines a first effective area. The valve also includes a biasing member configured to urge the piston, and a reference pressure passageway in fluid communication with the inlet and the second chamber. The valve can further include a piston seat that has a second inner effective area at least approximately equal to the first inner effective area.

Abstract: In one embodiment, a flow control valve includes a valve body having an inlet, an outlet, a flow passageway coupling the inlet to the outlet, and a cavity with first and second chambers. The valve further includes a hollow piston disposed in the first chamber and a seal separating the first and second chambers. The seal has a section within the piston that is exposed to the fluid in the first chamber. The section of the seal defines a first effective area. The valve also includes a biasing member configured to urge the piston, and a reference pressure passageway in fluid communication with the inlet and the second chamber. The valve can further include a piston seat that has a second inner effective area at least approximately equal to the first inner effective area.

Abstract: In one embodiment, a flow control valve includes a valve body having an inlet, an outlet, a flow passageway coupling the inlet to the outlet, and a cavity with first and second chambers. The valve further includes a hollow piston disposed in the first chamber and a seal separating the first and second chambers. The seal has a section within the piston that is exposed to the fluid in the first chamber. The section of the seal defines a first effective area. The valve also includes a biasing member configured to urge the piston, and a reference pressure passageway in fluid communication with the inlet and the second chamber. The valve can further include a piston seat that has a second inner effective area at least approximately equal to the first inner effective area.

Abstract: A valve comprises a valve body having an inlet and an outlet defining a flow passage through the valve body. A piston is mounted in a bore intersecting the flow passage and the piston divides the bore into first and second chambers. The piston remains substantially motionless during upstream pressure fluctuations after the desired fluid flow rate through the valve has been established. A reference pressure passage communicates with the inlet and the first chamber of the bore. Springs in the second chamber bias the piston against the fluid pressure from the first chamber. A sleeve on the piston is configured to variably sheath a cover over the outlet such that reciprocation of the piston during initiation of fluid flow through the valve varies the effective area of openings in the cover to achieve the desired differential pressure across the flow control throttle, thus setting the flow rate constant unless the throttle position is changed.

Abstract: A fluid flow control valve and actuator therefor for changing fluid flow rate. A fluid flow control valve comprises a housing having a bore and an inlet and an outlet which form a flow passage through the housing. The valve also comprises a piston mounted in the bore, a fluid flow orifice communicating with the inlet and the outlet, springs which bias the piston toward the inlet, and a valve seat which is matable with the piston and is slidable within the housing to vary fluid flow rate. An actuator for changing fluid flow rate of the valve is comprised of a housing having a bore, a piston dividing the bore into a first chamber and a second chamber, springs in the second chamber for biasing the piston toward the first chamber, an actuator fluid inlet communicating with the first chamber, and an actuator fluid outlet communicating with the first chamber.

Abstract: A valve comprises a valve body having an inlet and an outlet defining a flow passage through the valve body. A piston is mounted in a bore intersecting the flow passage and the piston divides the bore into first and second chambers. The piston remains substantially motionless during upstream pressure fluctuations after the desired fluid flow rate through the valve has been established. Springs in the second chamber bias the piston against the fluid pressure from the first chamber. A sleeve on the piston is configured to variably sheath a cover over the outlet such that reciprocation of the piston during initiation of fluid flow through the valve varies the effective area of openings in the cover to achieve the desired differential pressure across the flow control throttle, thus setting the flow rate constant unless the throttle position is changed.

Abstract: A constant flow rate controller valve includes a piston spring biased towards the top of the valve. Fluid or gas flowing into the valve increases the forces in the chamber above the piston, forcing the piston toward a valve seat. The piston is thus seated in the valve seat, blocking gas or fluid flow to the outlet port. The forces on the piston in the chamber below the piston builds as flow goes through the piston until the forces in this chamber including the piston spring force is greater than the forces in the chamber above the piston. The piston then is lifted from the valve seat, and the pathway to the outlet orifice is opened. At equilibrium, fluid or gas flows through or around the piston via the variable orifice.

Abstract: A constant flow rate controller valve includes a piston spring biased towards the top of the valve. Fluid or gas flowing into the valve increases the forces in the chamber above the piston, forcing the piston toward a valve seat. The piston is thus seated in the valve seat, blocking gas or fluid flow to the outlet port. The forces on the piston in the chamber below the piston builds as flow goes through the piston until the forces in this chamber including the piston spring force is greater than the forces in the chamber above the piston. The piston then is lifted from the valve seat, and the pathway to the outlet orifice is opened. At equilibrium, fluid or gas flows through or around the piston via the variable orifice.

Abstract: A constant flow rate controller valve includes a piston spring biased towards the top of the valve. Fluid flowing into the valve increases the forces in the chamber above the piston, forcing the piston toward a valve seat. The piston is thus seated in the valve seat, blocking fluid flow to the outlet port. The forces on the piston in the chamber below the piston builds as flow goes through the piston until the forces in this chamber including the piston spring force is greater than the forces in the chamber above the piston. The piston then is lifted from the valve seat, and the pathway to the outlet orifice is opened. Fluid flows through the piston via the calibrated orifice. An equilibrium flow rate is reached by variation in the piston position based on the location of the movable seat which sets and maintains a constant differential pressure.

Abstract: A constant flow rare controller valve includes a piston spring biased towards the top of the valve. Fluid or gas flowing into the valve increases the forces in the chamber above the piston, forcing the piston toward a valve seat. The piston is thus seated in the valve seat, blocking gas or fluid flow to the outlet port. The forces on the piston in the chamber below the piston builds as flow goes through the piston until the forces in this chamber including the piston spring force is greater than the forces in the chamber above the piston. The piston then is lifted from the valve seat, and the pathway to the outlet orifice is opened. Fluid or gas flows through the piston via the calibrated orifice. An equilibrium flow rate is reached by variation in the piston position based on the location of the movable seat which sets and maintains a constant differential pressure across the piston thus maintaining constant flow.

Abstract: A substantially constant flow regulating valve includes a piston dividing a bore into two chambers. The piston is spring biased toward the top chamber of the bore. Fluid from the inlet enters the top chamber through a reference pressure passage and exerts a downward force on the piston. Fluid from the inlet also passes through an inlet flow throttle and into the bottom chamber of the bore where it exerts an upward force on the piston in concert with the spring force. The piston includes an end which variably interacts with an orifice in the lower chamber to maintain a constant pressure differential between the top and bottom chambers.

Abstract: A substantially constant flow regulating valve includes a piston dividing a bore into two chambers. The piston is spring biased toward the top chamber of the bore. Fluid from the inlet enters the top chamber through a reference pressure passage and exerts a downward force on the piston. Fluid from the inlet also passes through a low torque inlet flow throttle and into the bottom chamber of the bore where it exerts an upward force on the piston in concert with the spring force. The piston includes an end which variably interacts with an orifice in the lower chamber to maintain a constant pressure differential between the top and bottom chambers. A coil-type piping system, a diversifying campus-type piping system and a pressure source piping system all include the above described flow regulating valve. None of these systems require balancing valves or differential pressure valves when the flow regulating valve is employed.

Abstract: A constant flow rate controller valve includes a piston spring biased towards the top of the valve. Fluid or gas flowing into the valve increases the pressure in the chamber above the piston, forcing the piston toward a valve seat. A pin type valve stem is thus seated in the valve seat, blocking gas or fluid flow to the outlet port. The pressure in the chamber below the piston builds until the pressure in this chamber plus the piston spring force is greater than the pressure in the chamber above the piston. The piston then lifts the valve stem from the valve seat, and the pathway to the outlet orifice is opened. Fluid or gas flows through the piston via the caibrated orifice. An equilibrium flow rate is reached by variation in the piston position based on the interaction of the above gas or fluid pressures and spring force.