Flowserve 10 ACCESS I Worcester Controls - Manual (Page 11)

WCAIM2028 10, 15, 20 ACCESS I and 10-40 Access M 39 Actuators Intrinsically Safe 11
SPRING-RETURN ACTUATOR
1. IMPORTANT: When less than the standard number of springs are
used in each end cap, these springs should be positioned
according to the air supply figures below.
Size 10–40
70 psi - 8 springs - 4 per end cap Remove center spring
60 psi - 8 springs - 4 per end cap Remove center spring
50 psi - 6 springs - 3 per end cap Use 3 on a diagonal
40 psi - 4 springs - 2 per end cap Use 2 in opposite corners
The values listed below are for standard and less than the
standard air pressure as required per the ordering code.
NOTE: Maximum Operating Pressure Does Not Change.
Ordering Code 4 5 6 7 ( )
Supply Pressure (psi) 40 50 60 70 80
Actuator Size End of Spring Torque (in-lb)
10 35 55 75 75 95
15 65 105 145 145 185
20 125 195 265 265 335
25 210 330 450 450 575
30 340 535 730 730 920
33 680 1,070 1,460 1,460 1,850
35 850 1,330 1,815 1,815 2,300
40 1,500 2,240 2,980 2,980 3,740
2. If a spring-return actuator is being repaired due to a failed spring,
REPLACE all the springs in this actuator, as well as any other
parts which may have been damaged.
3. When replacing the springs in a spring-return actuator, place the
springs in the end cap pocket after thoroughly lubricating each
spring. Be generous with lubricant!
4. With the springs pointing up and the end cap on a solid surface,
place the actuator body over the springs and the proper end cap.
(Each end cap can only be mounted to just one end of the
actuator body, as there is a “foolproof” pin in the end cap which
aligns with a hole in the body.)
5. Force the body down and begin by engaging two end cap screws
(5C) by hand through the end cap. Take each end cap screw up in
SMALL and EQUAL turns. Once the end cap is temporarily
secured to the body, turn the actuator over to its normal position
and uniformly take up the four end cap screws. Uniformly load all
the springs to prevent any spring from buckling.
IMPORTANT: Locating nibs are permanently cast into the sizes 25
through 40 actuator piston face. The actuator springs must fit
over these locating nibs on the piston face. Care in following the
above instructions will ensure the proper alignment of the spring
in the actuator body — proper contact with the piston face and
end cap.
6. In a similar manner, as in the previous steps, replace the springs
in the other end of the actuator body.
Flow Control
Worcester Controls