Bulletin 71.7:167D
June 2011
167D Series Switching Valves
P1185
TYPE 167D TWO-WAY SWITCHING VALVE
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 specifi c requirement by an adjusting screw atop the spring case.
P1184
TYPE 167DA THREE-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 benefi 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.
D103235X012
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Bulletin 71.7:167D
Specifi cations
Available Confi 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 Coeffi 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.
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Bulletin 71.7:167D
|
ADJUSTING SCREW |
|
ADJUSTING SCREW |
|
CONTROL SPRING |
|
DIAPHRAGM |
|
CONTROL SPRING |
|
O-RING |
SOFT SEAT |
DIAPHRAGM |
|
O-RING
PORT A |
PORT C |
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BODY |
VALVE STEM |
|
|
|
PORT A |
PORT C |
VALVE PLUG |
|
ORIFICE SEAT |
|
|
VALVE STEM |
VALVE SPRING |
|
|
BODY
VALVE PLUG
ORIFICE SEAT
M1152
VALVE SPRING |
M1151 |
|
PORT B |
TYPE 167D TWO-WAY SWITCHING VALVE |
TYPE 167DA THREE-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
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 switching valve.
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 onoff 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.
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