The control valve must be cleaned completely inside the housing components and stored/
shipped as it was received. Refer to Storage Preparations for cleaning instructions.
After the meter is shut down, refer to
Cylinder disassembly (NPS 2-8)
for the detailed
disassembly procedure.
After the previous steps have taken place, assemble the control valve per the instructions
in
9.3.1
Cylinder disassembly (NPS 2-8)
Procedure
1. Remove the compression fitting and tubing from the port Y connection on the
cylinder head.
2. Remove the nuts that secure the cylinder head to the valve body.
3. Alternately tighten the jack-out screws until the cylinder assembly is free to be lifted
out of the valve body.
4. Lift the cylinder assembly by the cylinder head. Remove it from the valve body and
set it in a vertical position with the cylinder head on top.
5. Before removing the screws, place the cylinder assembly in an arbor press to
immobilize the cylinder head. This is to prevent sudden spring pressure from being
released and causing injury or damage.
CAUTION
SPRING PRESSURE HAZARD
Follow the instructions in
Failure to comply may cause release of spring pressure, resulting in serious injury
or equipment damage.
6. Use an Allen wrench to remove the screws that secure the cylinder head to the
cylinder, and then gradually release the arbor press to remove the cylinder head
from the cylinder. Remove the indicator guard and the upper bearing first, if your
valve has a position indicator.
7. Remove the valve spring, indicator stem, retaining ring, washer, and piston from
the cylinder. Remove only the valve spring and the piston if your valve does not
have a position indicator.
8. With the cylinder in a vertical position (ports located on the top part of the
cylinder), place the piston, nose end up, into the recess between the cylinder and
the seat ring. Use an arbor press to push the piston into the cylinder, thus freeing
the seat ring from the cylinder.
Planned maintenance
User manual
October 2019
P/N 3-9008-556
74
Model 788DVC Digital Control Valve
Summary of Contents for Daniel 788DVC
Page 2: ...2 ...
Page 48: ...Introduction User manual October 2019 P N 3 9008 556 48 Model 788DVC Digital Control Valve ...
Page 88: ...Spare parts User manual October 2019 P N 3 9008 556 88 Model 788DVC Digital Control Valve ...
Page 90: ...Decommission User manual October 2019 P N 3 9008 556 90 Model 788DVC Digital Control Valve ...
