Abstract: A centerbody assembly for a valve includes: a centerbody having a process surface, at least one inlet orifice disposed in the centerbody and adapted to be disposed in fluid communication with a fluid at a process pressure, and at least one outlet orifice disposed in the centerbody separate from the at least one inlet orifice; an inlet port disposed in fluid communication with the at least one inlet orifice; an outlet port disposed in fluid communication with the at least one outlet orifice; and a flexible control diaphragm facing the process surface, wherein a perimeter of the control diaphragm is bonded to the centerbody so as to define a seal that blocks the passage of fluid.

Abstract: A method of operating a thermal system including at least a compressor, a condenser, a flow control valve, and at least one heat exchanger connected in a closed fluid loop charged with refrigerant. The method includes: regulating refrigerant pressure at a selected point within the fluid loop using a pressure regulating apparatus including: a main pressure regulator including a dome in fluid communication with a diaphragm that seals directly against at least one process void and at least one vent void; and a pilot pressure regulator in fluid communication with the dome so as to provide fluid thereto at a setpoint pressure. The setpoint pressure is maintained by the pilot pressure regulator utilizing refrigerant tapped from the fluid loop The refrigerant is tapped from a point upstream of the main pressure regulator and tapped refrigerant is returned to the fluid loop downstream of the main pressure regulator.

Abstract: A sealing apparatus for a back pressure regulator includes: a body defining a process surface, and including: at least one process void communicating with the process surface; a recess disposed in the process surface; a floating support hub disposed in the recess, carrying an O-ring; a vent void communicating with the recess; an inlet port disposed in fluid communication with the at least one process void and adapted to be coupled in fluid communication with a fluid at a process pressure; and an outlet port disposed in fluid communication with the vent void; and a diaphragm having opposed reference and process sides, the diaphragm disposed against the body such that the process side is substantially coplanar with the process surface.