167D Series Switching Valves
Bulletin 71.7:167D
June 2011
P1185
Figure 1. 167D Series Switching Valves
Introduction
The 167D Series switching valves are typically used
to deliver constant reduced pressure of gaseous
fl uids to pilot-operated controllers and other
pneumatic instrumentation.
• The Types 167D and 167DS are two-way
switching valves.
• The Types 167DA and 167DAS are three-way
switching valves.
Features
•
Compact—The Types 167D and 167DA
switching valves are engineered for outstanding
performance in a compact, lightweight package.
• Easy, Accurate Adjustment—With a choice of
springs for optimum resolution, the switching point
is set to a speci c requirement by an adjusting
screw atop the spring case.
P1184
TYPE 167DA THREE-WAY SWITCHING VALVETYPE 167D TWO-WAY SWITCHING VALVE
• Sour Gas Service Capability—NACE MR0175
and MR0103 compliant construction available.
• Optional Stainless Steel Construction—
The Types 167DS and 167DAS provide high
resistance to corrosion especially bene cial for
offshore applications.
• Ease of Maintenance—No special tools are
required to perform maintenance, and
all maintenance can be performed with the
valve in the line.
• Rugged Construction—The Types 167D and
167DA switching valves are engineered for longer
service life with minimal maintenance requirements.
• Corrosion Resistant Fasteners—Bolting and
adjusting screw are double zinc-chromated for
enhanced corrosion resistance. Optional stainless
steel bolting and adjusting screw are also available.
www. sherregulators.com
D103235X012
Bulletin 71.7:167D
Speci cations
Available Con gurations
Types 167D and 167DS: Two-way
switching valves
Types 167DA and 167DAS: Three-way
switching valves
Body Size, Inlet, and Outlet Connection Style
Ports A and C: 1/4 or 1/2 NPT
Vent and Control Pressure Connections
(Port D) and Port B: 1/4 NPT
Construction Materials
See Table 4
Maximum Operating Inlet Pressure
(1)
Types 167D and 167DS: 400 psig / 27,6 bar
Types 167DA and 167DAS: 125 psig / 8,6 bar
Types 167DA and 167DAS (NACE): 100 psig / 6,9 bar
Set Pressure Ranges
See Tables 1 and 2
Maximum Diaphragm Pressure
(1)
150 psi / 10,3 bar over outlet pressure setting up
to a maximum of 250 psi / 17,2 bar
Flow and Sizing Coef cients
See Table 3
Spring Case Vent Location
Aligned with inlet standard, other positions optional
Temperature Capabilities
(1)
Nitrile (NBR)
Standard Service (Types 167D and 167DA only):
-20° to 180°F / -29° to 82°C
Low Temperature Service (Types 167D and 167DA
only) and Standard Service (Types 167DS and
167DAS only): -40° to 180°F / -40 ° to 82°C
Fluorocarbon (FKM)
High Temperature Service: 0° to 300°F /
-18° to 149°C
Approximate Weights
Types 167D and 167DA: 1.2 pounds / 0,5 kg
Types 167DS and 167DAS: 2.8 pounds / 1 kg
Options
Types 167D and 167DA
• Handwheel adjusting screw
• Fluorocarbon (FKM) diaphragm, soft seat,
and O-rings
• Stainless steel valve stem and plug. Includes
stainless steel seat.
• 1-hole panel mount with handwheel adjusting
screw and 1/4 NPT tap spring case
• 3-hole panel mount bonnet with handwheel
adjusting screw and 1/4 NPT spring case
• 1/4 NPT tapped vent spring case
• 1/4 NPT tapped vent and closing cap
• Adjusting screw with locknut and a lock wire to
one fl ange bolt (For Type 167D only)
• Panel mounting bracket. Inlcudes 1/4 NPT
spring case, standard adjusting screw, nut,
and bracket.
• Yoke mounting bracket. Includes 1/4 NPT spring
case, standard adjusting screw, nut, fasteners,
and bracket.
• Size 30-70 casing mounting bracket. Includes
1/4 NPT spring case, standard adjusting screw,
nut, fasteners, and bracket
• NACE MR0175 or NACE MR0103 construction
(2)
Types 167DS and 167DAS
• Handwheel adjusting screw
• Fluorocarbon (FKM) diaphragm, soft seat,
and O-rings
• 1-hole panel mount with handwheel adjusting
screw and 1/4 NPT tap spring case
• Panel mounting bracket. Inlcudes 1/4 NPT
spring case, standard adjusting screw, nut,
and bracket.
• Yoke mounting bracket. Includes 1/4 NPT spring
case, standard adjusting screw, nut, fasteners,
and bracket.
• Size 30-70 casing mounting bracket. Includes
nut, fasteners, and bracket.
1. The pressure/temperature limits in this Bulletin and any applicable standard or code limitation should not be exceeded.
2. Product complies with the material requirements of NACE MR0175 or MR0103. Environmental limits may apply.
2
SOFT SEAT
OUTLET PRESSURE (WHEN LOADING PRESSURE IS LESS THAN SETPOINT)
INLET PRESSURE
OUTLET PRESSURE (WHEN LOADING PRESSURE IS EQUAL TO OR GREATER THAN SETPOINT)
ATMOSPHERIC PRESSURE
LOADING PRESSURE
O-RING
ADJUSTING SCREW
CONTROL SPRING
DIAPHRAGM
PORT A
Bulletin 71.7:167D
ADJUSTING SCREW
CONTROL SPRING
DIAPHRAGM
O-RING
PORT C
PORT A PORT C
VALVE STEM
BODY
ORIFICE SEAT
M1152
TYPE 167D TWO-WAY SWITCHING VALVE
INLET PRESSURE
OUTLET PRESSURE (WHEN LOADING PRESSURE IS LESS THAN SETPOINT)
OUTLET PRESSURE (WHEN LOADING PRESSURE IS EQUAL TO OR GREATER THAN SETPOINT)
ATMOSPHERIC PRESSURE
LOADING PRESSURE
VALVE PLUG
VALVE SPRING
BODY
ORIFICE SEAT
Figure 2. 167D Series Operational Schematics (Port D not shown)
Principle of Operation
Refer to Figure 2 and also refer to Figures 3 through
5 for port D location. Control pressure enters the
switching valves through Port D (not shown in Figure 2)
and registers under the diaphragm. Control pressure
overcomes the spring force and the diaphragm, and
raises the valve plug, closing port C and opening port
B of the Type 167DA three-way switching valve. In this
condition, the Type 167D construction is turned off and
the Type 167DA construction provides fl ow from path A
to B. If, either intentionally or through pneumatic failure,
the control pressure drops below the spring force, the
diaphragm and valve plug move downward, opening
port C and closing port B of the Type 167DA three-way
switching valve. In this condition both constructions
provide a fl ow path from port A to port C. The pressure
change necessary to switch the valve depends on the
spring used and the setting of the adjusting screw on the
Installation
The switching valve can be mounted in any position,
providing the vent in the spring case is free from
obstruction. Connect the pneumatic control line to
the port marked “D” on the valve body. Ports A and C
(and B on the Types 167DA and 167DAS valve) are
connected for the desired switching valve response to
loss or decrease in pneumatic pressure.
Figure 5 shows typical application of the Types 167DA
and 167DAS switching valve. If the control valve inlet
pressure falls below a predetermined setting, the on-
off controller turns off control pressure to the switching
valve. This causes the switching valve to bleed the
control valve diaphragm pressure to atmosphere, closing
the control valve. The control valve remains closed until
the inlet pressure is restored to the desired setting.
Dimensions are shown in Figure 7.
switching valve.
VALVE STEM
VALVE PLUG
VALVE SPRING
M1151
PORT B
TYPE 167DA THREE-WAY SWITCHING VALVE
3
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