T208VR Series
2
Specifications
The Specifications section lists the specifications for T208VR Series Tank Blanketing Vacuum Regulator. Factory
specifications, such as maximum temperature, maximum inlet and outlet pressures, spring range, orifice size and
material and seat material are stamped on the nameplate fastened on the regulator at the factory.
Warning
!
Failure to follow these instructions or
to properly install and maintain this
equipment could result in an explosion,
fire and/or chemical contamination
causing property damage and personal
injury or death.
Fisher
®
vacuum regulators must be
installed, operated and maintained
in accordance with federal, state and
local codes, rules and regulations
and Emerson Process Management
regulator Technologies, inc. (regulator
Technologies) instructions.
if the vacuum regulator discharges
process fluid or a leak develops in
the system, service to the unit may be
required. Failure to correct trouble could
result in a hazardous condition.
Call a qualified service person to
service the unit. installation, operation
and maintenance procedures
performed by unqualified person may
result in improper adjustment and
unsafe operation. Either condition
may result in equipment damage
or personal injury. Only a qualified
person shall install or service the
T208Vr Series vacuum regulators.
Available Configurations
Type T208Vr:
Direct-operated vacuum regulator
with internal pressure registration
Type T208VrM:
Direct-operated vacuum regulator
with blocked throat and control line connection for
external pressure registration
Body Sizes and End Connection Styles
(1)
BODY SiZE
EnD COnnECTiOn STYLES
inch
Dn
gray cast iron
316L/316 Stainless steel
3/4 or 1
20 or 25
NPT
NPT or CL150 RF
Maximum (Casing) Pressure
(1)
35 psig / 2.41 bar
Maximum (Casing) Vacuum Pressure
(1)
Full Vacuum
Maximum allowable Vacuum Pressure
(1)
See Table 1
Maximum Downstream Vacuum Pressure
(1)
Full Vacuum
Vacuum Control Pressure ranges
(1)
See Table 1
Pressure registration
Type T208Vr:
Internal
Type T208VrM:
External
Orifice Size
7/16-inch / 11 mm
Control Line Connection
1/2 NPT
Material Temperature Capabilities
(1)
nitrile (nBr):
-20 to 180°F / -29 to 82°C
Fluorocarbon (FKM):
40 to 300°F / 4 to 149°C
Spring Case Connection
1/4 NPT
approximate Weight
19 pounds / 8.6 kg
1. The pressure/temperature limits in this Instructional Manual and any applicable standard or code limitation should not be exceeded.
Principle of Operation
The T208VR Series vacuum regulators (Figure 2)
are used to maintain a constant vacuum at the
regulator inlet. A decrease in this vacuum (increase
in absolute pressure) beyond this value registers on
the diaphragm and opens the disk. This permits a
downstream vacuum of lower absolute pressure than
the upstream vacuum to restore the upstream vacuum
to its original pressure setting. On the Type T208VR,
pressure registers underneath the diaphragm. The
Type T208VRM has a control line connecting the
diaphragm casing to the vacuum line and an O-ring
stem seal blocking the throat causing registration
pressure to flow through the control line.
