Emerson Daniel 762, User Manual

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9.3 Mechanical disassembly
To ensure safe and accurate performance, only informed and trained personnel should
install, operate, repair and maintain this product.
WARNING!
PRESSURE HAZARD
The control valve is subject to pressurized fluids. Isolate the control valve upstream and
downstream.
Always depressurize the control valve before disassembly.
Failure to comply may cause high pressure fluids to leak, resulting in death or serious injury.
9.3.1 Cylinder disassembly (NPS 2-12)
1. Remove the nuts that secure the cylinder head to the valve body.
2. Alternately tighten the jack-out screws until the cylinder assembly is free to be lifted
out of the valve body.
3. 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.
4. 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 step 5.
Failure to comply may cause release of spring pressure, resulting in serious injury or
equipment damage.
5. 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.
6. 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.
7. Turn the cylinder over with the ports on top when removing the high pressure seat
ring. Remove the set screw from the seat ring. Turn the seat ring counterclockwise
to remove the seat ring and then remove the O-ring from the cylinder.
Planned maintenance
88 Daniel Models 762, 763, 765, 766 and 767 Control Valves