Instruction and maintenance manual – Marwin Valve UT Series Pneumatic Actuators User Manual
Page 2
INSTRUCTION AND MAINTENANCE MANUAL
MARWIN UT DESIGN 2011 PNEUMATIC ACTUATORS
Page 2 of 10
Bulletin IM-UT Dsgn2011_1114
Bulletin IM-UT 2011 Dsgn - 1112
3170 Wasson Road * Cincinnati, OH 45209 USA
Phone 513-533-5600 * Fax 513-871-0105
e-mail:
–ww
3
Function
The air pressure acts on the surface of the pistons (12) causing their alternate movement, which is converted into rotation (standard 90°) of the pinion
(2). As a result the pneumatic actuators can be used for remote operation of valves.
3.1 Double acting
(Standard execution shown – top view)
CLOSED
OPEN
P1 (IN AIR)
P2 (IN AIR)
Supplying air through port P1, the external chambers fill up and the
action of the pressure on the surface of the pistons (12) creates a force
(F) pushing them toward each other, generating a torque with
CLOCKWISE rotation.
3.2 Spring return
When the pistons (12) are close to the pinion, supplying air through
port P2 the internal chamber fills up and the pressure on the surface of
the pistons creates a force (F1) pushing them away from each other,
generating a torque with COUNTERCLOCKWISE rotation.
OPEN
CLOSED
P2 (IN AIR)
Supplying air through port P2, the internal chamber fills up and the action
of the pressure on the surface of the pistons (12) creates a force (F1)
pushing them away from each other, generating a torque with
COUNTERCLOCKWISE rotation.
4
Storage
The springs (M) are now compressed. Venting the air out of the internal
chamber through port P2 allows the springs (M) t o start extending
and apply a force (Fm) on the pistons (12) pushing them toward each
other, generating a torque with CLOCKWISE rotation.
It is recommended that the actuator be kept in clean and dry place. The state of preservation during the storage time is improved if the actuator is
preserved in the original packing box.
For a long storage period we recommend to periodically stroke the actuator one complete cycle by pressurizing the chambers.
The actuators have two air ports which should be plugged during storage to avoid intrusion of contaminants.
5
Maintenance
Maintenance should be performed by Marwin or other properly trained personnel. Marwin supplies spare parts (gaskets, guide elements) in appropriate
kits (except for lubricating grease). Maintenance may become necessary between 500,000 and 1,000,000 cycles, depending upon local service
conditions.
P2 (OUT AIR)
(Standard execution shown – top view)
2
F1
F1
12
F1
2
12
F1
12
2
m
(Springs)
Fm
Fm
12
F1
2
F1