6 N1 70 en
3
1
GENERAL
1.1
Scope of the manual
This instruction manual contains important information
regarding the installation, operation and maintenance of
Metso N1 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 N1 series actuators are pneumatic quarter turn cylinder
actuators designed for control and shut-off service. Design
is modular and enables an ideal configuration of pneu-
matic, central block and spring modules. Ductile cast iron
center body, fabricated carbon steel pneumatic module
and spring module provides rugged actuator construction.
The spring provides the required safety function; the valve
either opens or closes if the air supply is interrupted.
The mounting face dimensions of the N1 actuator comply
with the ISO 5211 standard.
The N1_E_C is spring to close type actuator. The yoke of the
actuator, when operated by the spring, rotates clockwise as
seen from the pointer cover side. The piston then moves
towards the frame side of the cylinder. The two keyways in
the yoke are positioned at an angle of 90° to each other,
making it possible to change the position of the actuator in
relation to the valve, see Fig. 1.
Fig. 1
Operating principle of the N1_E_C actuator
The N1_E_A is spring to open type actuator. The yoke of the
actuator, operated by the spring, rotates counter clockwise
as seen from the pointer cover side. The piston then moves
towards the frame side of the cylinder. The two keyways in
the secondary shaft (yoke) are positioned at an angle of 90°
to each other, making it possible to change the position of
the actuator in relation to the valve, see Fig. 2.
Fig. 2
Operating principle of the N1_E_A actuator.
The N1_D is a double acting actuator. The linkage mecha-
nism converts linear motion (provided by an air supply and
piston) to rotary motion. The yoke of the actuator rotates
clockwise (close) when cylinder supply is in rear port and
counter clockwise (open) when cylinder supply is in front
port, see Fig. 3.
Fig. 3
Operating principle of the N1_D actuator.
1.3
Actuator markings
The actuator is provided with an identification plate, see
Fig. 4.
Fig. 4
ID plate
Identification plate markings are:
1. Type
2. Manufacturing site, date, successive no. (bar code)
3. SO number or ID number (bar code)
4. Max. operating pressure
5. ATEX category and protection level
(1)
(2)
(3)
(4)
(5)
Summary of Contents for Neles N1 Series
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