Instruction manual

Instruction Manual
D500240X012
A31A Valve
October 2012
16
Figure 6. Typical Seal Installation
A5251-1*
LARGEST OUTSIDE
DIAMETER (KEY 5)
WARNING
Avoid personal injury or property damage caused by the impact of a falling or tipping valve. Support large valves during
maintenance.
7. To complete this step, stand the v alve up. Support the valve securely using methods appropriate for the valve size.
If a vise or other clamps are being used, make certain the flange gasket sealing area of the valve body is not
damaged.
8. Manually rotate the drive shaft (key 3) to turn the disk clockwise to meet the seal ring.
9. Place a piece of rubber, or other soft material, between the disk and internal travel stop to protect the disk. With a
rubber mallet, tap the disk until it contacts the internal travel stop. When the disk makes contact with the stop,
manually rotate the disk counterclockwise back out of the seal ring to a 90-degree open position.
10. The final seating of the retaining ring screws can now be done. For the screw torque values, refer to table 6.
11. Repeat steps 8 and 9 two more times.
Note
When attaching the actuator to the valve, make sure the valve disk is not in contact with the internal travel stop. The valve disk
should be positioned from 0.001 to 0.030 inch (0.03 to 0.76 mm) away from the internal stop in the valve body.
12. Use an appropriate tool (such as a feeler gauge) and position the disk from 0.001 to 0.030 inch (0.03 to 0.76 mm)
away from the internal stop in the valve body.
This adjustment is necessary to be certain that the actuator output torque is fully absorbed by the actuator travel stop
or by the actuator. The internal travel stop in the valve body should not absorb any of the actuator torque.
Cryogenic Seal Installation
Unless otherwise indicated, key numbers and part names are listed in figure 8.