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IMO-218 EN - Issue 8/2020
1. GENERAL
1.1 SCOPE OF THE MANUAL
This instruction manual contains important information regarding
the installation, operation and maintenance of Neles RNP series
actuators. Please read these instructions carefully and save them
for future reference.
The manual can be changed or revised without any prior notice. Any
changes in product’s specification, structure, and/or any components
may not result immediate revised version of the manual.
1.2 STRUCTURE AND
OPERATION
The RNP series actuators are pneumatic quarter turn cylinder
actuators designed for control and shut-off service.
A rack and pinion actuator is a type of actuator that comprises a
pair of gears which converts piston linear motion into drive shaft
rotational motion.
Pinion engages teeth on a rack; linear motion applied to the rack
causes the pinion to move relative to the rack, thereby translating
the linear motion of the rack into rotational motion.
“A”
“B”
“A”
“B”
Double-Acting (Top View)
Air supplied to
Port A
forces pistons apart and toward end
positions with exhaust air exiting at
Port B
(a counterclockwise
rotation is obtained).
Air supplied to
Port B
forces pistons toward center with exhaust
air exiting at
Port A
(a clockwise rotation is obtained).
Figure 1.
Operating principle of the double acting version
Spring-Return (Top View) Spring-to-Close
“A”
“B”
“A”
“B”
Air supplied to
Port A
forces pistons apart and toward end
position, compressing springs. Exhaust air exits at
Port B
(a counterclockwise rotation is obtained).
Loss of air pressure allows springs to force pistons toward center
position with exhaust air exiting at
Port A
(a clockwise rotation is
obtained).
Figure 2.
Operating principle of the spring to close version
1.3 ACTUATOR MARKINGS
The actuator is provided with an identification plate, see Fig. 3.
Figure 3.
ID plate
Identification plate markings are:
1.
Type
2.
Manufacturing site, date, successive no.
3.
SO number or ID number
4.
Max. operating pressure
5.
ATEX category and protection level
Summary of Contents for Easyflow RNP Series
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