Data Sheet

Bulletin 71.7:167D
5
Overpressure Protection
The 167D Series switching valves 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. Overpressuring any
portion of a switching valve or associated equipment
may cause leakage, parts damage, or personal injury
due to bursting of pressure-containing parts or explosion
of accumulated gas. Switching valve operation within
ratings does not preclude the possibility of damage
from external sources or from debris in the pipeline.
A switching valve should be inspected for damage
periodically and after any overpressure condition.
Figure 5. Typical Switching Valve Application Figure 6. 167D Series Vent Positions
POSITION 1 (ALIGNED WITH INLET) (STANDARD)
POSITION 3
POSITION 4 POSITION 2
GE31784
GE37992
TYPE 657
TYPE DVC6010/
67CFR
CHECK VALVE
1/4 NPT
3/4 NPT
VOLUME TANK
SHIPPED WITH
ACTUATOR
FACTORY (1/4 O.D.) OR
CUSTOMER SUPPLIED TUBING
(PIPED BY CUSTOMER)
ASCO SOLENOID
DE-ENERGIZED
TYPE 167DA
OR 167DS
A
B
C
D
1
2
3
S
SUPPLY
VENT
Universal NACE Compliance
Optional materials are available for applications
handling sour gases. These constructions comply with
the recommendations of all NACE International sour
service standards.
The manufacturing processes and materials used by
Emerson™ assure that all products speci ed for sour
gas service comply with the chemical, physical, and
metallurgical requirements of NACE MR0175 and/or
NACE MR0103. Customers have the responsibility to
specify correct materials. Environmental limitations
may apply and shall be determined by the user.
Figure 3. Typical 167DA or 167DAS Installation
(Lockup system using Type 167DA or 167DAS
to close air circuit to diaphragm of main valve in
case of plant air failure. Main valve will remain in
position it occupied at time of supply pressure failure.)
Figure 4. Typical 167D or 167DS Installation
(Warning system using Type 167D or 167DS two-way
valve to activate a whistle when pump discharge
pressure falls.)
AF8400
COOLING TOWER
PUMP
PUMP DISCHARGE
PRESSURE GAUGE
TYPE 167D OR 167DS SWITCHING
VALVE SET TO OPEN AT
5 PSI / 0,34 bar
WHISTLE
TO INSTRUMENT AIR SUPPLY
55 PSI / 3,8 bar
A
C
TYPE
67CFR
10C0622
1/4 NPT
SUPPLY
TYPE
DVC6010
TYPE 657
TYPE
167DA OR
167DAS
A
B
A
B
C
D
D