Emerson Process Management 1051 - Manual (Page 14)

Instruction Manual
D100320X012
1051 and 1052 H & J Actuators
October 2012
14
b. For push-down-to-open action–Consult the appropriate instruction manual for determining the closed position
of the valve or other operated equipment. Release all pressure from the diaphragm casing, making sure the
diaphragm is against its up travel stop. Be sure that the optional handwheel is adjusted to its topmost position so
that the closed position of the actuator and valve body or other operated equipment can be reached
simultaneously. Check the position of the valve body or other operated equipment with respect to its properly
closed position. Stroke the actuator so the turnbuckle (key 57) is accessible through the access opening. Adjust
the linkage. Release pressure to the actuator, and check the new adjustment. Continue this procedure until the
operated equipment is in the closed position when the actuator is resting on its up travel stop. Tighten locknut
(key 16). Stroke the actuator, and tighten the left-hand threaded locknut (key 58). Tighten each locknut to the
appropriate torque value listed in table 11.
WARNING
Exceeding any torque requirements could damage the actuator and impair safe operation.
5. Replace the access plate (key 59). Also, replace the machine screws (key 60), if present.
6. Loosen the self-tapping screws (key 38), and adjust the travel indicator (key 37). Retighten the self-tapping screws.
1052 Spring Adjustment
Initial Compression
The 1052 nameplate specifies a spring set, which is the initial compression adjusted into the actuator spring, Initial
compression is the casing pressure at which the diaphragm and diaphragm rod begin to move away from the up travel
stop with the actuator disconnected from the valve body or other operated equipment. (With the actuator connected
and pressure applied to the valve body or other operated equipment, a higher casing pressure will be required to start
actuator travel). The initial compression was selected (based upon the service conditions specified when the actuator
was ordered) so that when the actuator and valve body or other operated equipment are in service, the operated
equipment will close properly and full travel will be obtained within a diaphragm casing pressure range of 0 to 1.2, 0 to
2.3, 0 to 2.8 or 0 to 3.8 bar (0 to 18, 0 to 33, 0 to 40, or 0 to 55 psig) depending on specific actuator size and
construction.
If the actuator has been disassembled or if the spring adjustment was changed, and it is desired to match the initial
compression stated on the nameplate, make sure the rod end bearing (key 17, figure 13) has been disconnected from
the lever (key 27, figure 13). Adjust the spring so that the diaphragm rod just starts to travel at the spring set pressure
specified on the nameplate. Be sure the rod end bearing does not hit the lever as the diaphragm and diaphragm rod
move away from the up travel stop.
To adjust the spring, insert a round rod into one of the slots in the lower bearing seat (key 73, figure 13). Slot diameter
is 9.5 mm (3/8-inch) for size 40 actuators, 15.9 mm (5/8-inch) for size 60 actuators, and 19.1 mm (3/4-inch) for size 70
actuators.
Rotate the bearing seat to move it toward the casings (keys 1 and 2, figure 13) to increase initial compression or away
from the casings to decrease initial compression.