Operation - Graco DC12 Operation & Setup

Operation

General Information all
configurations
1. Before operating DC12 perform all setup,
priming, and ratio check procedures.
CAUTION
Do not dispense through mixer until machine has
been primed through Ratio Check Valves. If
system is not full of material prior to dispensing
out of mixer the machine could be damaged. See
Priming Section of this manual.
2. Refer to Table 1 for recommended running
pressures.
3. Ratio Check Samples are recommended
during start up, drum change, flow rate
change, or any maintenance. In addition
Ratio Samples should be taken on a regular
schedule as a means of quality control to
insure machine is pumping properly. (See
Ratio Check section in this manual)
4. Flow Rate is determined by Ram Supply
pump air pressure. The DC12 is driven with
the A side supply ram (BE). Refer to Fig. 24
The A Side Supply Pressure will be higher
than the B Side. Table 1 lists tested
pressure combinations. Different flow rates
are achievable by reducing A and B air
motor pressures. When making flow rate
changes the following should be observed
and changed if necessary:
a) A Inlet and Outlet Pressures are
balanced during dispense cycle. The
inlet and outlet sides of the metering
pump should be within 300 psi (2.1Mpa,
20.1Bar)
b) B Inlet and Outlet Pressures are
balanced during dispense cycle. The B
inlet pressure should be less than
double the B outlet pressure.
47
CAUTION
To prevent damage to the Mixer Assembly
perform the Mixer Flush Procedure located in this
manual. Remove the Lower Dispense Block and
Mixer for additional cleaning during regular
maintenance.
312767B