Fisher 67DFR Instrument Supply Filter Regulator
Fisher 67DFR Filter Regulator has a filter and internal relief valve with a soft seat for
reliable shutoff with no discernible leakage.
Fisher 67DFR model of regulators are typically used to deliver constant reduced pressure
of gaseous fluids to pilot-operated
controllers and other pneumatic instrumentation. As shown in the
Available Configurations table, an assortment of regulators
is available to meet diverse flow requirements.
Available Configurations
| Connection Size | 1/2" NPT |
| Maximum Inlet Pressure | 250 psig / 17.2 bar |
| Spring Range | 0-125 psi/ 0-8.6bar |
| Pressure Registration | Internal |
| Smart Bleed Check Valve Set point | 6 psi / 0.41 bar differential |
Temperature Capabilities
With Nitrile (NBR):
Standard Bolting: -20 to 180°F / -29 to 82°C
With Gauges: -40 to 180°F / -40 to 82°C
Fisher 67CFR Internal Relief Performance
Low capacity for minor seat leakage only; other overpressure
protection must be provided if inlet pressure can exceed the
maximum pressure rating of downstream equipment or exceeds maximum
outlet pressure rating of the regulator.
Smart Bleed Check Valve Set point
6 psi / 0.41 bar differential
Fisher 67CFR Filter Regulator : Filter Capabilities
Free Area: 12 times pipe area
Micron Rating: Polyethylene Filter (Standard): 5 microns Glass Fiber Filter (Optional): 5 microns PVDF or Stainless Steel Filter (Optional): 40 microns
Drain Valve and Spring Case Vent Location
Aligned with inlet standard, other positions optional
Principle of Operation
67CFR Filter Regulator Downstream pressure is registered internally on the lower side of
the diaphragm. When the downstream pressure of Filter Regulator is
at or above the set pressure, the valve plug is held against the
orifi ce and there is no fl ow through the regulator. When demand
increases, downstream pressure drops slightly allowing the spring
to extend, moving the stem down and the valve plug away from the
orifi ce. This allows fl ow through the regulator.
Internal Relief (Types 67CR, 67CSR, 67CFR, and 67CFSR)
If for some reason, outside of normal operating conditions, the
downstream pressure exceeds the setpoint of the regulator, the
force created by the downstream pressure will lift the diaphragm
until the diaphragm is lifted off the relief seat. This allows flow
through the token relief. The relief valve on the Type 67CR, 67CSR,
67CFR, or 67CFSR is an elastomer plug that prevents leakage of air
from the downstream to atmosphere during normal operation, thereby
conserving plant air.
Smart Bleed Airset
In some cases, it is desired to exhaust downstream pressure if
inlet pressure is lost or drops below the setpoint of the
regulator. For example, if the regulator is installed on equipment
that at times has no flow demand but is expected to backflow on
loss of inlet pressure. The Types 67CFR and 67CFSR can be ordered
with the Smart Bleed option which includes an internal check valve
for this application. During operation, if inlet pressure is lost,
or decreases below the setpoint of the regulator, the downstream
pressure will back flow upstream through the regulator and check
valve. This option eliminates the need for a fixed bleed downstream
of the regulator, thereby conserving plant air.
Overpressure Protection
The 67C Series filter regulators have maximum outlet pressure
ratings that are lower than their maximum inlet pressure ratings. A
pressure relieving or pressure limiting device is needed if inlet
pressure can exceed the maximum outlet pressure rating.
Types 67CR, 67CSR, 67CFR, and 67CFSR have a low capacity internal
relief valve for minor seat leakage only. Other overpressure
protection must be provided if the maximum inlet pressure can
exceed the maximum pressure rating of the downstream equipment or
exceeds the maximum outlet pressure rating of the regulator.
