Masoneilan 72000 Series Control Valves Instruction Manual | 13
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Actuation
Type 87/88 Multi-Spring Diaphragm Actuators
Connecting Type 87 (Air to Extend)
No. 6 Actuator (Figure 11)
1. Tightly assemble the hex nuts (1) onto the plug stem.
2. Push down the actuator, and screw on the yoke nut (33) at the
same time. Then assemble the bottom stem connector (2). As
soon as it becomes possible, insert the valve stem into the
actuator stem (10). The stem must be inserted far enough so
that when there is no air in the actuator, the valve plug does
not touch the seat.
3. Tighten the yoke nut (33).
4. Supply air to the actuator at the final pressure.
5. Use the pointer (7) to set the travel scale (9) to the valve open
position.
6. Supply the actuator with air at a sufficiently high pressure to
obtain a travel equal to the nominal travel of the valve.
7. Unscrew the plug stem until the valve plug is in contact with
the seat. Do not turn the valve plug on the seat as this could
damage the sealing surfaces.
8. Screw the hex nuts (1) as far as they will go and check that
operation is correct.
Connecting Type 88 (Air to Retract)
No. 6 Actuator (Figure 11)
1. Tightly assemble the hex nuts (1) onto the plug stem.
2. Push down the actuator, and screw on the yoke nut (33) at the
same time. Then assemble the bottom stem connector (2). As
soon as it becomes possible, insert the valve stem into the
actuator stem (10). The stem must be inserted far enough so
that when there is no air in the actuator, the valve plug does
not touch the seat.
3. Tighten the yoke nut (33).
4. Unscrew the valve plug stem until the valve plug comes into
contact with the seat. Do not turn the valve plug on the seat as
this could damage the sealing surfaces.
5. Supply air to the actuator until the stem has travelled at least
.40 inches (10 mm).
6. Unscrew the plug stem by the number of turns N1 specified in
Table 4.
Note: For model 724XX valves, use the N2 values in Table 4 to
ensure seating tightness of the pilot plug.
7. Screw the hex nuts (1) as far as they will go and check that
operation is correct.
8. Use the pointer (7) to set the travel scale (9) to the valve
closed position.
Connecting Type 87 (Air to Extend) No. 10, 16
and 23 Actuators (Figure 11)
1. Tightly assemble hex nut (1) onto the plug stem.
2. Screw the top stem connector (4) assembly tightly onto the
actuator stem (10).
3. Push down the actuator, and screw on the yoke nut (33) at
the same time. Then assemble the bottom stem connector (2)
assembly by screwing until it comes into contact with the hex
nut (1).
4. Push down the actuator and tighten the yoke nut (33).
5. Supply the actuator with air at the initial pressure indicated on
the spring scale.
6. Position the stem connector assembly at distance “X” indicated
in Table 5.
7. Use the pointer (7) to set the travel scale (9) to the valve open
position.
8. Supply the actuator with air at a high enough pressure
to obtain a travel equal to the nominal travel of the valve.
Note: For model 724XX valves, reduce the travel by Value A
indicated in Table 6.
9. With the plug correctly positioned on the seat, unscrew the
bottom stem connector (2) assembly until it comes into contact
with the top stem connector (4). Tighten the socket head cap
screws (5), hex nut (1) and lock nut (32) and check that the
operation is correct.
Connecting Type 88 (Air to Retract) No. 10, 16
and 23 Actuator (Figure 11)
1. Supply the actuator with air to retract stem.
2. Unscrew the top stem connector (4) in accordance with
dimension “X” in Table 5.
3. Tightly assemble hex nut (1) onto the plug stem.
4. Tightly screw the top stem connector (4) assembly onto the
actuator stem (10).
5. Push down the actuator, and screw on the yoke nut (33) at
the same time. Then assemble the bottom stem connector (2)
assembly by screwing until it comes into contact with the hex
nut (1).
6. Push down the actuator and tighten the yoke nut (33).
7. With the plug correctly positioned on the seat, unscrew the
bottom stem connector (2) assembly to bring it into contact
with the top stem connector (4).
8. Supply air to the actuator until the stem has travelled at least
0.40 inches (10 mm).
9. Unscrew the top stem connector (4) by the number of turns N1
specified in Table 4 then lock manually with hex nut (1).
Note: For model 724XX valves, use N2 values in Table 4 to
ensure seating tightness of the pilot plug.
Plug Stem
Diameter
N1
(turn)
N2
844XX
(turn)
in
mm
1"
1.25
4.75
0.09
2.3
3/4"
1.25
4.25
0.08
2.0
5/8"
1.5
3.5
0.08
2.0
1/2"
1.5
3
0.075
1.9
Table 4 - Type 88, Air to Retract - valve seating
