Type A31A
3
Table 2. Material Temperature Ratings
COMPONENT, ANSI CLASS,
TEMPERATURE RANGE
COMPONENT, ANSI CLASS,
MATERIAL OF CONSTRUCTION
_
F
_
C
Seal Ring
See Figure 2
Backup Ring
Soft Seal
Fluoroelastomer
EPR
Nitrile
PTFE
Neoprene
Phoenix III Seal
Fluoroelastomer
EPR
Nitrile
Neoprene
Cryogenic Seal
Aluminum (Optional)
-20 to 400
-65 to 360
-20 to 200
-100 to 400
-45 to 300
-40 to 500
-80 to 400
-40 to 300
-65 to 300
-425 to 400
-29 to 204
-54 to 182
-29 to 93
-73 to 204
-43 to 149
-40 to 260
-62 to 204
-40 to 149
-59 to 149
-254 to 204
Shaft Packing
(1)
PTFE
Graphite
In Oxidizing Media
In Inert or Reducing Media
-425 to 450
-425 to 1000
-425 to 1500
-254 to 232
-254 to 538
-254 to 816
Shaft
(2)
17-4PH H1025
17-4PH H1150M
K-Monel
Inconel 718
Nitronic 50
-100 to 800
-320 to 800
-425 to 900
-425 to 1300
-320 to 1100
-73 to 427
-195 to 427
-254 to 482
-254 to 704
-196 to 593
Bearings
PEEK
(3)
(standard)
316 SST
PTFE Composition
Bronze
-100 to 500
-425 to 1500
-425 to 325
-425 to 500
-73 to 260
-254 to 816
-254 to 163
-196 to 260
Disk Hardfacing
Electroless Nickel Plating or
hard chrome coating
CoCr-A
(4)
(Alloy 6)
-425 to 1000
-325 to 1500
-254 to 538
-198 to 816
1. These low temperature limits apply to the flowing media. Valve extensions
provided for cryogenic service maintain higher temperatures at the packing box.
2. Shaft material may affect the valve pressure rating. Consult your Fisher Controls
sales office or sales representative.
3. PEEK stands for PolyEtherEtherKetone
4. CoCr-A hardfacing degrades shutoff performance of the seal. Consult your Fisher
Controls sales office or sales representative.
CAUTION
The valve configuration and construc-
tion materials are selected to meet par-
ticular pressure, temperature, pressure
drop, and controlled fluid conditions.
Because pressure drop and temperature
range capabilities limit some combina-
tions of materials, do not apply any oth-
er conditions to the valve without first
contacting your Fisher Controls sales
office or sales representative.
The maximum allowable inlet pressures for Type A31A
valves are consistent with the applicable pressure/
temperature ratings except where limited by material
capabilities shown in figure 2 and table 2.
Adjusting the Actuator Travel Stops
WARNING
The edges of a rotating valve disk have
a shearing effect that may result in per-
sonal injury. To avoid personal injury,
keep clear of the disk edges when rotat-
ing the disk.
CAUTION
When using an actuator, the actuator
travel stops or the actuator travel (for
actuators without adjustable stops)
must be adjusted so that the disk stop
in the valve body does not absorb the
output of the actuator. Failure to limit
actuator travel as described in the next
step can result in damage to the valve
shafts or other valve parts.
1. Locate the actuator travel stop that establishes the
closed position of the valve disk. When adjusting the
travel stop or travel, make sure that the disk is from
0.001 to 0.030 inch (0.03 to 0.76 mm) away from the
internal stop in the valve body. This adjustment is nec-
essary to be certain that the actuator output torque is
fully absorbed by the actuator travel stop or by the ac-
tuator. The internal travel stop in the valve body
should not absorb any of the actuator torque.
2. Before installing the valve/actuator assembly in the
process line, cycle the valve several times to be sure
the valve disk returns to the proper position.
Valve Orientation
Note
The 10- through 12-inch class 150
valves and 8- through 12-inch class 300
valves have a two-piece shaft. The shaft
with the keyed end is called the drive
shaft. The shaft opposite the drive shaft
is called the follower shaft.
The 3- through 8-inch class 150 valves
and 3- through 6-inch class 300 valves
have a one-piece shaft. This one-piece
shaft is keyed and is called the drive
shaft.
Whenever possible, install the valve
with the shaft in the horizontal position
as shown in figure 5.
Horizontal installation can enhance
valve performance because process
