I
MO-D52/R52
18
9/21 Rev. 0
Assembly
Assembling the actuator
When assembling the actuator, reverse the disassembling procedure found in “Disassembling the actuator”
section. Replace the worn or damaged parts, if found, with new ones. Supply the lubricant, shown in the
“Periodic Inspection” section, to the sliding surfaces of actuator rod, torque lever, roller unit and manual
operation unit.
When assembling the diaphragm, be sure that the rubber side (KOSO mark side) is the side, to which air
pressure is applied.
Be sure to use new parts for the o-ring 130.
Replace the diaphragm 108 and the packing 117 about every 5 years.
Assembling the actuator and the valve
Assemble the actuator and the valve unit as follows.
•
Set the yoke in the same position as before disassembling it and fix it with the hex socket set screw
132. Then completely tighten the yoke nut to reverse direction as shown in Fig. 13. Use the same tools
and procedure, which were used for separating them.
•
Lower the stem 5 and check that the plug contacts the valve seat surface.
• When installed on a Hammel Dahl control valve, the stem 5 will require a stem adapter as shown
in Fig. 12A. Prior to installing the stem connector, install the stem adapter and locking nut.
• Thread the locking jam nut to the bottom of the valve stem thread, allowing the nut to remain
loosely fitted.
• Thread the stem adapter onto the valve stem completely. No additional torque is required.
• Thread the locking jam nut toward the stem adapter, contacting the stem adapter and with
sufficient force to lock the adapter in place.
•
Follow the instructions given in the “Operation” section-(2) “Adjustment of actuator off-balance”.
Adjustment after Assembly
On completion of the assembly, check the following. If there are any trouble, disassemble the unit, find and
remove the cause, and then reassemble it again.
•
Apply the specified air-pressure to the actuator and check that it operates smoothly.
•
Check that the leakage quantity of the valve seat is within the specified value.
•
Check the hysteresis and linearity are within the specified values.
Follow the instructions in “Installation” for mounting the assembly on the piping after adjustment of it.
