ARI Armaturen DP34 Tridem EN - Manual (Page 13)

0040504001 2010 Page 13
Operating and installation instructions
Pneumatic actuators - DP34T / DP34Tri
5.7 Assembling the valve, operating mode
„actuator stem retracts by spring force“
Straightway valves will be opened by spring force on air failure (Fig. 10).
Flow B - AB of 3-way mixing valves will be opened by spring force on air failure (Fig. 11).
- In case the valve and actuator have been delivered separately, the plug with stem are to
be set into the terminal position by means of pressing „OPEN.“
- In the case of the three-way mixing valves, the terminal position is the horizontal
throughway A-AB.
- Loosen the cylinder-screws.
- Remove the safety flange and threaded bushing from the actuator coupling.
- Screw the locknut onto the valve stem.
- Place the safety flange over the valve stem and screw the threaded bushing onto the
valve stem.
- Check that the actuator has been set into the correct operating mode.
- Actuators with manual emergency adjustment:
Check the position of the manual emergency adjustment, please refer to Fig. 4.
- Connect the control pressure line to the connection of the diaphragm cover (pos. 18), at
design with manuel handwheel at the upper diaphragm base (pos. 7) and pressure
measuring equipment.
- Drive the actuator with control pressure in midtravel (in the middle of the spring range).
- Place onto the valve traverse and fasten by means of hexagon-nuts.
5.8 Setting the starting point, operating mode
„actuator stem retracts by spring force“
- Set the actuator unit to the desired starting point of the spring range.
- Screw back the threaded bushing on the valve stem until the top corner of the coupling
flange appears in the groove and fits tightly.
Simultaneously, the plug must be set in the OPEN position.
(The three-way valves must be adjacent to the plug in the casing seat.)
- Hereby, attention must be given, that the valve stem is in deep enough into the
threadbush.
If need be, screw back the coupling flange.
- Fasten the safety flange by means of cylinder-screws onto the coupling flange.
- Check to see that the starting point of the spring range, the plug lifts out of the terminal
position and after obtaining the control pressure-target value, that the valve motion drives
through and is resting on the valve seat.
- After a test run, adjust the position indicator (adjusting ring with set screw) to the terminal
positions and screw both locking nuts tightly. (at a ca. 50% lifting positioning)
(Do not turn the plug on the valve seat while under contact pressure.)
ATTENION !
- During assembly jobs, the plug on the valve seat is not allowed to be turned
while under contact pressure.