IMO 11/19
4
IMO-553 EN
“2”
“4”
“2”
“4”
Double-Acting (Top View)
Air supplied to Port 2 forces pistons apart and toward end
positions with exhaust air exiting at Port 4 (a counterclockwise
rotation is obtained).
Air supplied to Port 4 forces pistons toward center with exhaust
air exiting at Port 2 (a clockwise rotation is obtained).
Figure 1
Spring-Return (Top View) Spring-to-Close
“2”
“4”
“2”
“4”
Air supplied to Port 2 forces pistons apart and toward end
position, compressing springs. Exhaust air exits at Port 4 (a
counterclockwise rotation is obtained).
Loss of air pressure allows springs to force pistons toward center
position with exhaust air exiting at Port 2 (a clockwise rotation is
obtained).
Figure 2
3.
INSTALLATION
3.1
General
1. Check to see that the desired failure mode is correct
(Figures 1 & 2). In the spring-to-close mode, the actuator
will cycle clockwise to close upon loss of pressure. If the
spring-return actuator is not set up in the configuration
desired, follow the disassembly procedure section 4.2.
Reverse the orientation of the pistons, then reassemble
following the assembly procedure, section 4.3.
2. Mount the actuator to the valve, following the direction
in the linkage AMI or valve IMO.
3. Connect a regulated air supply to the NPT fitting
in the actuator housing. CAUTION: The maximum
operating pressure is 116 psi (8 bar).
4. Adjust the stop screws following ASSEMBLY Section 4.3.5.
3.2
Operation
1. The actuator series, size, operating pressure, operating
temperature, output torque, spring directions, and
drive type is determined by the actuator designation.
2. The label lists the actuator series, size, operating
pressure, maximum pressure, and serial number.
3. Actuator designation example, VPVL300SR6BD is
a spring-return series, VPVL300 double-opposed piston
actuator that has 80-psi (5.5-bar) springs, a Teflon®-
coated anodized housing (protection B), an end-of-
spring-stroke output torque of 44.9 FT•LBS (60.8 N•m).
4.
MAINTENANCE
4.1
General
Although Metso’s
Jamesbury
actuators are designed to work
under severe conditions, proper preventative maintenance
can significantly help to prevent unplanned downtime and
in real terms reduce the total cost of ownership. Metso
recommends inspecting actuators at least every five (5)
years. The inspection and maintenance frequency depends
on the actual application and process condition.
NOTE: All VPVL actuator fasteners are metric. Under normal
operating conditions the actuator requires only periodic
observation to ensure proper adjustment. Repair kits are
available to replace seals and bearings (soft parts). These
parts are identified in (Figure 23) and listed in (Table 3).
(Table 1) below lists kit part numbers.
4.2
Disassembly
When disassembly of the actuator is required for maintenance,
remove the actuator from the valve. Ensure proper lifting
procedures are followed when moving or carrying actuators.
CAUTION: Do not use the M5 VDI / VDE mounting holes or
the M6 hole in the pinion for lifting the actuator.
