DirectFlo DF1400
Chapter 5: Trouble-Shooting and Repair
Comco Inc.
5-14
Issue Date: January 2009
Inspecting and Repairing the PowderGate
(cont’d)
Removing and Disassembling the PowderGate. (Ref Appendix B, Figure 10)
1.
Remove the valve seat assembly as described above.
2.
Disconnect the 3 air lines connected to the PowderGate. It is suggested
that these lines be labeled for easy identification during re-installation.
3.
Remove the 4 socket head screws located on the top of the PowderGate
and lift the assembly up and out of the machine.
4.
To disassemble the PowderGate. Remove the 4 socket head cap screws
located at the rear of the cylinder. The PowderGate should now be able
to be pulled apart.
5.
Inspect all of the internal parts for excessive wear and look for any
noticeable amounts of abrasive leaking past the felt wipers and collecting
around cylinder shaft where it enters the cylinder. The felt wipers are a
normal wear item. It is a good practice to replace them whenever the unit
is disassembled for normal inspection and maintenance.
6.
Test the cylinder for free and smooth piston movement. The piston on the
air cylinder assembly can become eroded from the abrasive flow and
should be paid special attention when inspecting internal parts. The
piston is part of the cylinder assembly and is replaced as a complete unit.
7.
Reassemble and install the PowderGate by reversing the above steps.
8.
Be sure the O-ring is in the PowderGate base prior to installing the
assembly into the machine.
PowderGate Delay Adjustment
The PowderGate’s control valve air source is
equipped with a delay valve (flow control), at the
regulator to prevent it from opening for 45 - 60
seconds after internal pressure is released. This
allows the tank pressure to escape through the
vent hose, rather than the nozzle. This flow
control is set at the factory and should not
require and further adjust
ment. However, if the PowderGate opens too quickly when depressurizing, or fails to
open, the flow control adjustment can be checked. The delay valve has a locking ring
and an adjustment knob. Loosen the locking ring by turning counterclockwise then
adjust the delay valve with the knob by turning it fully clockwise until it stops. Turn knob
back out counterclockwise 1/4 to 1/2 turn. Tighten the locking ring in place. If the delay
cannot be properly set, it will be necessary to replace the flow control valve.
Delay Adjustment
