DirectFlo DF1400
Chapter 4: Maintenance
Comco Inc.
4-5
Issue Date: January 2009
Parts Subject to Normal Wear
(cont’d)
Hose Connectors
The connectors that attach the hoses to the DirectFlo
®
DF1400 are also subject to
abrasive wear. These include the PowderGate exit connector (ST4184), the Handpiece
Nose (PF2090) and the Vent Hose Bulkhead Connector (ST4014). Be sure to check
them each time you replace hoses. Refer to Chapter 5 of this manual when replacing
hose or hose connectors.
Nozzles
Although manufactured from a high grade of tungsten carbide, nozzles are usually
subject to the greatest wear. They may start to bell-mouth (widen) within a few hours
and be 50% oversize within a day, depending on the aggressiveness of the abrasive
powder, the pressure, and the duty cycle. Refer to Chapter 3 of this manual when
changing nozzles.
Tank Orifice
The orifice controls the amount of abrasive injected into the mixing chamber. The
abrasive nature of the blasting media will cause the orifice to erode over time, increasing
in diameter. As the size of the orifice changes the abrasive flow increases, potentially
clogging the nozzle or reducing the efficiency of the abrasive.
PowderGate
The PowderGate is a control valve for turning ON and OFF the abrasive flow to the
nozzle. The PowderGate has been designed for minimal maintenance. During normal
operation it is very easy to monitor the functioning of the PowderGate valve. While the
footswitch is not depressed, place a finger over the tip of the nozzle feeling for any
escaping air. Air escaping from the nozzle is an indicator that the blue nosepiece of the
PowderGate needs to be replaced.
Periodically the valve will need to be maintained. Normal maintenance includes
removing the four screws that retain the valve seat assembly and inspecting the blue
nosepiece. In addition the valve seat assembly will need to be inspected for grooves or
channels that may inhibit proper sealing of the nosepiece. These two items are
designed as standard replacement items for the PowderGate valve.
