Back-Pressure Regulators
General description:
A back-pressure-regulator maintains a system-pressure. Superfluos media overflows within the flow-band belonging to any type of regulator while the regulated pressure is kept constant. Typcial application: filling-systems (carbon dioxide etc.)
One differentiates in:
- spring-loaded, piston- or diaphragm-sensing
- dome-loaded, mostly diaphragm-sensing
or a combination of both: a differential back-pressure-regulator, which is preset by a spring to a constant inlet-pressure while a referential pressure allows the regulator to follow the varying system requirements.
Function:
a sensing area (piston or diaphragm) is loaded with a force either by spring or compressed gas. It thus keeps a mechanically detached poppet on its seat. When system- pressure rises byond set-pressure the piston/diaphragm will rise, moving the poppet via a retainer from the seat: media can flow.
When system-pressure falls the poppet will throttle and finally close the seat again. The differential between opening and leak-tight sealing is 5% of the opening pressure.
With larger seat-diameters and especially with varying downstream pressure (e.g. pressure-banks), it is advisable to apply balanced poppets. Thus fluctuations in the banks pressure will hardly affect regulated-pressure of the system.
Special solutions of our range include regulators multiplying a pilot-pressure. For example: Ratio 1:5 regulates 5 bar inlet with only 1 bar pilot pressure, the ratio being mechanically fixed.
|