Fisher 655 User Manual

Page of 16
655 and 655R Actuators
Instruction Manual
Form 1292
July 2007
2
Table 1. Specifications
Actuator Sizes and Maximum Casing Pressures
ACTUATOR
MAXIMUM CASING PRESSURE
ACTUATOR
SIZE
Bar
Psig
3A, 4A
17.2
250
3B, 4B
12.1
175
32, 42
6.9
100
33, 43
4.5
65
34, 44
3.1
45
35, 45
2.1
30
36, 46
1.0
15
Actuator Pressure Setting Ranges
See table 2
Actuator Yoke Boss and Valve Stem Connection
Diameters
Sizes 3A through 36: 54 mm (2-1/8 inch) yoke
boss with 9.5 mm (3/8 inch) stem connection
Sizes 4A through 46: 71 mm (2-13/16 inch) yoke
boss with 12.7 mm (1/2 inch) stem connection
Maximum Travel
Sizes 3A and 4A: 11 mm (0.4375 inch) plus 
3 mm (0.125 inch) for seating
All Other Sizes: 19 mm (0.75 inch) plus 3 mm
(0.125 inch) for seating
Effective Diaphragm Area
See table 3
Spring Rate
See key 6 in the parts list section
Temperature Capabilities
–29 to 82
_C (–20 to 180_F) with standard
diaphragm material. For the fluid and temperature
capabilities of nonstandard diaphragm materials,
consult your Emerson Process Management
sales office
Casing Pressure Connections
1/2 NPT internal
Approximate Weights
ACTUATOR
APPROXIMATE WEIGHT
ACTUATOR
SIZE
Kg
Lb
3A, 3B, 32, 33
20
45
34, 35, 36
23
50
4A, 4B, 42, 43
29
65
44, 45, 46
34
75
Specifications
Specifications for the Type 655 and 655R actuators
are shown in table 1. Information for a specific
actuator is also found on the nameplate of that
actuator.
Installation
WARNING
To avoid personal injury or property
damage caused by bursting of
pressure-retaining parts, be certain the
service conditions do not exceed the
casing pressure limits listed in table 1.
Use pressure-limiting or
pressure-relieving devices to prevent
service conditions from exceeding
these limits.
Always wear protective gloves,
clothing, and eyewear when
performing any installation operations
to avoid personal injury.
Check with your process or safety
engineer for any additional measures
that must be taken to protect against
process media.
If installing into an existing
application, also refer to the WARNING
at the beginning of the Maintenance
section in this instruction manual.
Type 655 and 655R actuators are normally shipped
mounted on a valve. Refer to the appropriate valve
instruction manual when installing the valve in the
pipeline. If the actuator is shipped separately or if it
is necessary to mount the actuator on the valve,
perform the procedures described in the Actuator
Mounting portion of this section.