Instruction Manual
D500237X012
M Series Actuator
February 2019
6
If the rim force required to rotate the handwheel exceeds the rim force listed in table 2, 3, or 4, check for the following
conditions:
D
Insufficient lubrication
D
Seized actuator parts
D
Excessive pressure drop across the valve
D
Obstruction to the valve disk rotation
If the manual actuator does not seem to control the process fluid, the worm or drive sleeve gear teeth may be broken,
the handwheel pin may be sheared, or the valve parts may be broken. Purchase a replacement manual actuator if
necessary. Refer to the valve instruction manual if valve maintenance is needed.
Lubrication
The interior parts of the M Series actuator should be lubricated on a regular schedule with a quality gear lubricant. The
interior parts should also be lubricated whenever difficulty in handwheel rotation indicates a need for lubrication.
1. Isolate the control valve from the line pressure, release pressure from both sides of the valve body, and drain the
process media from both sides of the valve.
2. Remove the cap screws that secure the gearbox cover plate and remove the gearbox cover plate.
3. Coat the worm, the drive sleeve gear teeth, and the bearing surfaces of the gearbox housing and worm with a
quality gear lubricant.
4. Replace the cover plate and cap screws using the bolt torques listed in table 5.
5. Replace the manual actuator on the valve. Adjust the actuator travel stop to limit the open and closed positions of
the valve disk following the steps in the appropriate valve instruction manual.
Parts Ordering
When corresponding with your
Emerson sales office
indicate the size of the M Series actuator. The size is stamped on
the gearbox. You should also provide the serial number of the valve.
WARNING
Use only genuine Fisher
™
replacement parts. Components that are not supplied by Emerson Automation Solutions should
not, under any circumstances, be used in any Fisher valve, because they will void your warranty, might adversely affect the
performance of the valve, and could give rise to personal injury and property damage.
